Serb. Astron. J. } 197 (2018), 13 - 33 UDC 524.333.7 : 524.6DOI: https://doi.org/10.2298/SAJ180316002J Original scientific paper
ANOMALOUS CEPHEIDS DISCOVERED IN A SAMPLEOF GALACTIC SHORT PERIOD TYPE II CEPHEIDS
M. I. Jurkovic1,2
1Astronomical Observatory, Volgina 7, 11060 Belgrade, Serbia2Konkoly Thege Miklos Astronomical Institute, Research Centre forAstronomy and Earth Sciences, Hungarian Academy of Sciences
H-1121 Budapest, Konkoly Thege Miklos ut 15-17, HungaryE–mail: [email protected]
(Received: March 16, 2018; Accepted: June 28, 2018)
SUMMARY: We revisited the short period Type II Cepheids (T2Cs), called theBL Herculis (BLHs), in the Galactic Field to derive a homogeneous analysis of theirFourier parameters.
Only V-band data were compiled to make sure that it was directly compara-ble between the known variables of the OGLE-III catalogue and the 59 individualobjects classified as short period Type II Cepheids in the General Catalogue ofVariable Stars (GCVS) we had in our sample. The derived Fourier parameters wereused to make distinction between different classes of variables.
From the 59 stars we found 19 BLHs, 19 fundamental mode Anomalous Cepheids(ACs) (8 of them were already known from the Catalina Sky Survey (CSS)), 1 firstovertone AC, 2 were found to be possible peculiar W Virginis (pWVir), 11 classicalCepheids (DCEPs), and 7 stars were not pulsating variables at all. As a result wecreated a list of bright BLH stars in the Galactic Field, and separated the ACs, aswell as other objects that were misclassified. The number of true BLHs decreasedin our sample by more than 50%. We gathered the metallicity from spectroscopicmeasurements published in literature. While the number of actual measurementsis low, it is highly suggestive that ACs are metal poor. The mean metallicity from8 measurements in 4 stars (UY Eri having 5 different [Fe/H] data points) is -1.12dex, but if the higher value metallicity outliers of UY Eri are left out the meanmetallicity becomes -1.88 dex, regardless if the AC is in the Milky Way itself or in acluster. On the other hand, BLHs seem to have a Solar-like metallicity of 0.00 dexaveraged from 21 measurements of 10 stars.
Key words. Stars: variables: Cepheids – Stars: Population II
1. INTRODUCTION
The short period Type II Cepheids (T2Cs),called BL Herculis (BLHs) subtype, are low mass(≈ 0.5 − 0.6 M¯) pulsating stars with periods be-tween 1 − 4 days. BLHs pulsate only in the funda-
mental mode (F). A summary of these objects wasgiven in Wallerstein (2002) and Catelan and Smith(2015). In the past the General Catalogue of VariableStars (GCVS1, Samus et al. 2009a, 2017) was thebiggest source of the classification of variable stars,but with the emergence of the big sky observing pro-grams their lists became somewhat outdated, so we
c© 2018 The Author(s). Published by Astronomical Observatory of Belgrade and Faculty of Mathematics, University ofBelgrade. This open access article is distributed under CC BY-NC-ND 4.0 International licence.
1http://www.sai.msu.su/gcvs/gcvs/
13
M. I. JURKOVIC
decided to revisit the BLHs subtype to see how theycompare with the other datasets. In the GCVS theBLHs are marked with ”CWB” and candidates with”CWB:”. The boarder between the short period andlonger period W Virginis (CWA) stars was put at 8days, which got outdated by the results of the T2Csfrom the Optical Gravitational Lensing ExperimentIII (OGLE-III) catalogue (Soszynski et al. 2008,2010b, 2011b). In the latest OGLE-IV cataloguecomposed of stars in the Galactic bulge (Soszynski etal. 2017) the border between BLHs and WVir starswas moved from 4 to 5 days for the Bulge.
Anomalous Cepheids (ACs) are stars whichhave similar period range (0.24 − 4 days), but theirmasses are higher 1.2 − 1.8 M¯. In the instabil-ity strip (IS) of the Herztsprung-Russell diagram(HRD) they are just above the T2Cs, see Bono etal. (1997b), Fiorentino et al. (2006), Groenewegenand Jurkovic (2017b). ACs pulsate in the funda-mental mode (F) and in the first overtone (1O). Inthe OGLE-III catalogue we have seen (Soszynski etal. 2008, 2010a,b) that T2Cs and ACs form a dif-ferent Period-Luminosity (PL) relations in the LMCand SMC. Groenewegen and Jurkovic (2017a,b) con-firmed this in their papers calculating the luminosi-ties (L), effective temperatures (Teff), masses (M),radii (R) and the bolometric PL relation for theT2Cs and ACs in the LMC and SMC. The numberACs identified in the LMC and SMC in the OGLE-IVcatalogue is 174 F and 76 1O pulsators. In Soszynskiet al. (2017) the number of identified ACs in theGalactic bulge has risen to 20 (19 F and 1 1O).
In Catelan and Smith (2015) it is stated thatmost of ACs have been discovered in dwarf spheroidalgalaxies, in the Magellanic Clouds (MCs), and a fewin globular clusters, but only a handful in the MilkyWay (MW). The whole subgroup of ACs is also knowas BLBOO in the GCVS, and it was named afterthe variable BL Bootis, which was considered to bethe only ACs in the MW, and it turned out to be amember of the galactic globular cluster NGC 5466.The discovery was made by Zinn and Dahn (1976),and studied in detail e.g. by McCarthy and Nemec(1997), Nemec and McCarthy (1998). Szabados etal. (2007) published a detailed study of XZ Ceti,confirming it to be a 1O AC, making it the secondAC discovered in the MW.
Articles in the literature about T2Cs mightfurther complicate the understanding of the classi-fication, since the derived properties of these vari-ables were interpreted differently. We give a shortoverview of these papers, but a longer summary isgiven in Catelan and Smith (2015). Diethelm (1983)has published a classification of pulsating stars basedon the shape of their light curves. V716 Oph, BF Ser,CE Her, VX Cap, XX Vir, EK Del, UY Eri and UXNor were labelled RR Lyrae Type d (RRd). Petersenand Diethelm (1986) concluded that the properties ofthe T2Cs known at that time is not uniform, and the
stars known as RRds are singled out as forming a dif-ferent group. To make things more complicated thenomenclature of the RR Lyrae (RRL) variables hasadded a subclass also called RRd, which describesan RRL simultaneously pulsating in the F and 1O,with a period ratio of 0.745, and the upper limit ofthe RRL variables is established to be at 1 day (e.g.see Catelan and Smith 2015).
The Catalina Sky Survey (CSS), see Drakeet al. (2014a), published their catalogue and theyhave detected 64 ACs in total (Drake et al. 2014b).The following six stars overlap with our BLH sam-ple: FY Vir, BF Ser, VX Cap, XX Vir, V1149 Her,and V716 Oph. Then in 2017 they published a newCatalina Southern Survey (Drake et al. 2017) withadditional 153 ACs, and two more stars overlappedwith our sample: V563 Cen and BI Tel. Most re-cently Soszynski et al. (2017) added 20 new ACs de-tected in toward the Galactic center by the OGLE-IVprogram.
Wallerstein (2002) dealt with the question ofmetallicities of T2Cs. Most of the data available atthat point were estimated from different photometricsystems (Diethelm 1990, Harris 1981). Nevertheless,there was a separation between a group of stars thatwere very metal-poor, and the ones that had metal-licities larger than −0.3.
We have looked into 128 stars in the GCVS,but found the V-band data for only 59 stars that werepreviously classified in the GCVS as CWB stars. Ap-plying the Fourier analysis, and comparing our re-sults to the V-band dataset of ACs and T2Cs inthe LMC from OGLE-III we reclassified the abovementioned 59 stars comparing their Fourier param-eters to the OGLE-III sample. We have made clearwhich of these objects are known cluster members(open and globular), since their evolution can belinked to the history of evolution of the clusters thatis separate from the individual stars in the Galaxy.The spectroscopically measured metallicites, as wellas, other derived physical parameters were gatheredfrom the literature. It is important to separate thesetwo varaible star types, since they do have signifi-cantly different ages, as a result of having differentinitial masses, and the clearance on their true num-bers in the MW should be useful to future research invariety of fields, for example in the evolutionary mod-elling of stars or understanding the star formationhistory of our Galaxy. T2Cs are old objects makingit possible to constrain some early star forming re-gions to a specific metallicity content helping futuregalactic evolution modelling. Because the origin ofACs is still not clear − they could be either a resultof interacting binaries or they could have come fromsingle star evolution - their contribution to galacticarchaeology is not that straightforward, but becausethey are found in dwarf spheroidal, irregular, spiralgalaxies (such as the MW or the LMC), even some-times in globular cluster, and they are metal-poor,they could give an insight to the intermediate-age (1-6 Gyrs) star formation mechanism in these systems.
14
ACs DISCOVERED IN A SAMPLE OF GALACTIC SHORT PERIOD TIICs
2. THE DATA
The comparison sample was taken from theOGLE-III catalog for the LMC BLHs and ACs. TheFourier parameters published in the online catalogueare derived from the I-band data, so we have col-lected the OGLE-III Soszynski et al. (2008, 2010b)V-band data and did the Fourier analysis ourselves.
In the Milky Way we have started with the128 stars classified in the GCVS as short periodT2Cs or possible short period T2Cs. We were ableto find datasets for 59 stars in that list. We havecollected the available data from the All Sky Auto-mated Survey (ASAS-32), see Pojmanski (1997), inV-band for 34 stars. This search did not includeall the objects in the GCVS list, so additional lightcurve data were collected from various publicly avail-able databases: CSS3 (Drake et al. 2009, 2014),INTEGRAL4 and individual published papers, suchas Berdnikov (2008), Henden (1980), Kwee and Di-ethelm (1984), Schmidt and Reiswig (1993), Schmidtet al. (2005), Soszynski et al. (2011b), and in onecase data from the American Association of VariableStar Observers (AAVSO5). We have added the sourceof the data for each star in the Appendix Table A.1.
While there are other sources (for example theSuperWASP6) with very good data, we could not useit for our comparative Fourier analysis, because theywere collected in a broad band or no filter.
3. THE FOURIER ANALYSIS ANDCLASSIFICATION PROCEDURE
We have used the Period04 program (Lenz andBreger 2004), which uses this equation:
A = Z +∑
Ai sin(2Π(ωit + φi)). (1)
We have proceeded to get the Fourier param-eters, defined by these equations:
Ri1 =Ai
A1, (2)
and:φi1 = φi − iφ1, (3)
where i = 2, 3, for the light curve analysis.This kind of Fourier decomposition was pre-
sented by Petersen and Diethelm (1986) based onthe amplitude ratio (Ri1) and phase differences (φi1)defined in Simon and Lee (1981). It is a useful toolfor the automation of the classification.
With the publication of the OGLE-III data,a long spanning precise photometric information be-came available, making it possible to compare other
stars to the known variables of the OGLE sam-ple. We have concentrated our attention on theLMC dataset, because the Wessenheit index vs. logP for T2Cs and the F and 1O ACs separate veryclearly (this is true for the SMC too, but we omittedthat sample, because the number of ACs was muchsmaller than in the LMC). When we go back to theFourier parameters, we can be assured that this is agood indication of the type, and this is the samplewe have compared our 59 Field stars against. Allthe Fourier parameters were converted to match theones from the OGLE-III catalogue.
The calculated values of the Fourier param-eters are given in the Appendix, see Tables A.1,A.2 and A.3. The Fourier parameters are plottedin Figs. 1a, 1b, 1c, 1d. The ACs from the OGLE-III LMC sample and from the MW are plotted withpurple, while the BLH from both datasets are green,to help the reader distinguish between the types ofthe Fourier parameter plots. The DCEPs are darkgrey, and the possible pWVirs stars are orange.
In addition to the Fourier parameters we havelooked into the amplitudes of the detected harmon-ics (A2 and A3). Figs. 2 and 3 show how the T2Csand ACs separate for the LMC and Galactic stars(the color coding is the same as in Figs. 1a, 1b,1c and 1d). ACs have higher harmonic frequencyamplitudes than T2Cs. There are a few stars thatare overlapping. In the case of BQ CrA and V745Oph this can be a consequence of the noisy data setthat was used for the Fourier analysis. In the caseof UY Eri the discrepancy in the Figs. 2 and 3 isattributable to the behaviour of the star.
The classification is based on an iterative pro-cess. Since the the OGLE BLHs and ACs are sep-arated on their period-luminosity relation, we tooktheir Fourier parameters as a comparison sample. Tomake sure that all the Fourier parameters are ho-mogeneous we have used only the V-band data foreach examined star. The first step was to see wherethe OGLE LMC and MW stars overlap on all thesix Fourier parameter plots. The φ21 parameter wasthe least helpful in distinguishing these types. Thismethod, however, does not give a clear classificationfor each object, since the Fourier parameters over-lap in some cases. For this reason we did not applyany statistical criteria for the classification. Instead,when the classification of an object was not clear welooked at the light curve shape visually to confirmthe result, and furthermore reviewed the previouslypublished literature for individual stars to verify theresult. The BLHs and ACs separated most clearlyin Figs. 2 and 3. In the cases where we felt that astar showed some peculiarities we have expanded ourfinding in individual paragraph.
2http://www.astrouw.edu.pl/asas/
3http://nesssi.cacr.caltech.edu/DataRelease/
4https://sdc.cab.inta-csic.es/omc/
5https://www.aavso.org/
6http://www.superwasp.org/
15
M. I. JURKOVIC
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
-0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1
R21
log P [days]
OGLE LMC BLHOGLE LMC AC F
OGLE LMC AC 1OMW BLH
MW AC FMW AC 1OMW DCEP
MW pWVir?
(a)
0
0.1
0.2
0.3
0.4
0.5
0.6
-0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1
R31
log P [days]
OGLE LMC BLHOGLE LMC AC F
OGLE LMC AC 1OMW BLH
MW AC FMW AC 1OMW DCEP
MW pWVir?
(b)
0
1
2
3
4
5
6
7
-0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1
φ 21
log P [days]
OGLE LMC BLHOGLE LMC AC F
OGLE LMC AC 1OMW BLH
MW AC FMW AC 1OMW DCEP
MW pWVir?
(c)
0
1
2
3
4
5
6
7
-0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1
φ 31
log P [days]
OGLE LMC BLHOGLE LMC AC F
OGLE LMC AC 1OMW BLH
MW AC FMW AC 1OMW DCEP
MW pWVir?
(d)
Fig. 1. The logarithm of periods is plotted against the Fourier parameters R21, R31, φ21 and φ31 with theirerrors. The same color indicates the same classes for variables from the OGLE LMC and from the MW.The OGLE LMC BLHs are plotted in green crosses, the MW BLHs are green squares. The purple crossesrepresent the OGLE LMC AC F stars, the OGLE LMC AC 1O purple stars, the MW AC F are plotted aspurple filled squares and MW AC 1O star is plotted as a purple circle. The MW DCEP are plotted as darkgrey circles. Orange dotted triangles stand for possible pWVir stars.
0
0.05
0.1
0.15
0.2
0.25
0.3
-0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1
A2
[mag
]
log P [days]
OGLE LMC BLHOGLE LMC AC F
OGLE LMC AC 1OMW BLH
MW AC FMW AC 1OMW DCEP
MW pWVir?
Fig. 2. Log P vs. A2 for stars in the LMC. Thedescription is the same as in Fig. 1.
0
0.05
0.1
0.15
0.2
-0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1
A3
[mag
]
log P [days]
OGLE LMC BLHOGLE LMC AC F
OGLE LMC AC 1OMW BLH
MW AC FMW AC 1OMW DCEP
MW pWVir?
Fig. 3. Log P vs. A3 for stars in the field. Thedescription is the same as in Fig. 1.
16
ACs DISCOVERED IN A SAMPLE OF GALACTIC SHORT PERIOD TIICs
11.4
11.6
11.8
12
12.2
12.4
12.6
12.8
13 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=1.023 days
(a) FY Aqr
14
14.2
14.4
14.6
14.8
15
15.2
15.4 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=1.077 days
(b) V563 Cen
15.6
15.8
16
16.2
16.4
16.6
16.8
17 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=1.082 days
(c) FY Vir 12.4
12.6
12.8
13
13.2
13.4
13.6
13.8
14
14.2
14.4
14.6 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=1.091 days
(d) PP Tel
11.2
11.4
11.6
11.8
12
12.2
12.4
12.6
12.8 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=1.116 days
(e) V716 Oph
13
13.5
14
14.5
15
15.5
16 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=1.123 days
(f) DF Hyi 14.6
14.8
15
15.2
15.4
15.6
15.8
16
16.2
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=1.138 days
(g) BH Cet
11
11.2
11.4
11.6
11.8
12
12.2
12.4
12.6
12.8
13 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=1.165 days
(h) BF Ser
11.5
12
12.5
13
13.5
14 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=1.166 days
(i) BI Tel 13
13.5
14
14.5
15
15.5
16 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=1.172 days
(j) V2733 Oph
11.2
11.4
11.6
11.8
12
12.2
12.4
12.6
12.8
13 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=1.209 days
(k) CE Her
14
14.2
14.4
14.6
14.8
15
15.2
15.4
15.6 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=1.327 days
(l) VX Cap 11.4
11.6
11.8
12
12.2
12.4
12.6
12.8
13
13.2 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=1.348 days
(m) XX Vir
13.2
13.4
13.6
13.8
14
14.2
14.4
14.6 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=1.409 days
(n) V1149 Her
12.8
13
13.2
13.4
13.6
13.8
14
14.2
14.4
14.6 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=1.481 days
(o) MQ Aql 10.8
10.9
11
11.1
11.2
11.3
11.4
11.5
11.6
11.7 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=2.213 days
(p) UY Eri
12.5
13
13.5
14
14.5
15 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=2.386 days
(q) UX Nor
Fig. 4. The phased light curves of ACs in the MW with photometric errors.
17
M. I. JURKOVIC
4. RESULTS
Here we give the results of our analysis, sepa-rating each star into their variable class, and givingadditional details about them when necessary. It isimportant to treat variable stars which are membersof a globular or an open cluster separately from theindividual stars in the MW, because we need to dif-ferentiate initial conditions at the birth of these stars,and the evolutionary processes that take place inthese objects from those in the Galaxy. Contaminat-ing the Galactic sample with these variables is goingto influence our understanding of the MW evolutionitself, and lessen our knowledge about the clusters.
4.1. The anomalous Cepheids
Soszynski et al. (2011a) and Soszynski et al.(2011b) show in their variable star distribution thatthe 1 day limit they have adopted for making adifferentiation between the RRLs and T2Cs is wellfounded in observations. The ACs bridge the spanof both these variable types, as well as the DCEPs.The problem in the MW sample is that it is muchmore difficult to disentangle each of these variableson a PL relation, since the reddening is changingsignificantly in different directions. This is why ex-amination of properties of light curves is the bestway to proceed.
The CSS (Drake et al. 2014a) used the Stet-son variability index (JWS) to identify variabilityof the observed objects, and then applied a Lomb-Scargle periodogram analysis. The total number ofACs they have found is 64, and most of them arenewly discovered variables, but six overlap with oursample: FY Vir, V716 Oph, BF Ser, VX Cap, XXVir, V1149 Her. We confirmed these stars. In Drakeet al. (2017) CSS published a list of 156 ACs inwhich two more stars were overlapping: V563 Cenand BI Tel. From our Fourier parameter plots wehave found additional fundamental mode ACs: FYAqr, PP Tel, DF Hyi, BQ CrA, BH Cet, V2733 Oph,CE Her, MQ Aql, V745 Oph, UY Eri, UX Nor, andone possible first overtone AC: V742 Cyg, see Figs.4 and 5.
We present the list of ACs with their positions(RA (h:m:s), DEC (d:m:s), eq=J2000) taken fromSimbad7, the derived median V magnitude with ad-ditional data from the literature Teff , log g, [Fe/H],and the classification from the CSS in Table 1.
The detailed Fourier parameters can be foundin Appendix Table A.1.
The phased light curves of AC stars are pre-sented in Fig. 4.
There are individual objects that we neededto expand on, because their interpretation needs fur-ther explaining.
FY VirThe phased light curve of FY Vir (P=1.082
days) seen in Fig. 4c shows a well defined modula-tion.
V742 CygZejda et al. (2012) states that V742 Cyg
(P=0.936 days) is a member of the open clusterDolidze 37. The data for our analysis was publishedby Schmidt and Reiswig (1993). In the VizieR cata-log the data for V742 Cyg was wrongly published un-der the name ”V741 Cyg”, which is a known eclips-ing binary of Algol type with a period of P=4.649850days. The correctly phased light curve can be seenin Fig. 5. Vasil’Yanovskaya (1978), Schmidt (1990),and Schmidt (1991) all discussed that V742 Cygshows a significant period variation (with a periodaround P=0.93979 days) that is different from theBlazhko effect in RRL stars. Based on the Fourierparameters it is an AC, possibly a 1O AC, makingthis star the first possible AC to be discovered in anopen cluster.
15.4
15.5
15.6
15.7
15.8
15.9
16
16.1
16.2
16.3
16.4 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=0.936 days
Fig. 5. V742 Cyg phased light curve with aP=0.936 days.
V716 OphV716 Oph (P=1.116 days) is a member of the
globular cluster ω Centauri (NGC 5139), Dinescu(2002). The estimated age of ω Cen is 11.52×109
yrs. Resulting from our Fourier parameters V716Oph is an AC, confirming the results of Drake et al.(2014a).BI Tel
The classification of this object has been shift-ing during the years. Layden (1994) lists BI Tel(P=1.166 days) as an ”RRab” type RRL, and gets[Fe/H]=−1.96 dex for the metallicity. Than withthe ASAS-3 observations, the classification changedto ”DCEP-FU” (Pojmanski et al. 2005), to be re-classified, again, to an ”RR Lyrae FM” by Richardset al. (2012). Our Fourier parameters show it to bean AC.BQ CrA and V745 Oph
BQ CrA (P=1.128 days) and V745 Oph(P=1.596 days) have light curves that show a lot ofscatter (see Fig. 6), so their new classification maybe wrong, and needs further confirmation.
7http://simbad.u-strasbg.fr
18
ACs DISCOVERED IN A SAMPLE OF GALACTIC SHORT PERIOD TIICs
12
12.2
12.4
12.6
12.8
13
13.2
13.4
13.6
13.8
14 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=1.128 days
(a) BQ CrA
12.2
12.4
12.6
12.8
13
13.2
13.4
13.6 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=1.596 days
(b) V745 Oph
Fig. 6. The phased light curves of BQ CrA (left) and V745 Oph (right) showing significant scatter fromASAS-3 data.
Table 1. The identified ACs among the BLHs in the MW.
Name RA (h:m:s) DEC (d:m:s) < V >[mag]
P[days]
Teff
[K]log g[cgs]
[Fe/H][dex]
References CSS
V742 Cyg 20:02:32.77 +37:46:34.8 15.886 0.936FY Aqr 22:16:34.99 −03:48:55.41 12.359 1.023V563 Cen 14:49:50.89 −38:53:08.4 14.798 1.077 ACFY Vir 12:14:13.52 +06:01:17.1 16.419 1.082 ACPP Tel 20:16:56.51 −51:15:11.4 13.622 1.091V716 Oph 16:30:49.47 −05:30:19.5 12.169 1.116 6550 2.500 −1.870 Soubiran et al.
(2016)AC
DF Hyi 01:40:49.20 −67:29:41.9 14.336 1.123BQ CrA 18:37:01.38 −38:04:34.5 13.132 1.128BH Cet 00:50:02.80 −17:36:26.9 15.490 1.138BF Ser 15:16:28.50 +16:26:39.69 12.093 1.165 ACBI Tel 18:18:17.56 −53:22:19.8 12.814 1.166 − − −1.96 Layden (1994) ACV2733 Oph 17:31:21.880 −17:43:39.51 14.469 1.172CE Her 17:41:56.55 +15:04:30.2 12.170 1.209VX Cap 21:06:22.51 −18:49:39.8 14.859 1.327 ACXX Vir 14:16:48.59 −06:17:15.06 12.326 1.348 ACV1149 Her 16:03:43.36 +50:13:33.43 13.995 1.409 − − −2.32 Allende Prieto
et al. (2000)AC
MQ Aql 19:40:55.69 +12:37:10.1 13.812 1.481V745 Oph 17:20:02.93 +03:48:56.0 13.942 1.596UY Eri 03:13:39.13 −10:26:32.40 11.294 2.213 6800 1.800 −1.430 Soubiran et al.
(2016)638962809978
3.252.584.15
0.010.100.30
Schmidt et al.(2011)
6000 1.5 −1.8 Maas et al.(2007)
UX Nor 16:27:44.70 −56:47:08.1 13.644 2.386
19
M. I. JURKOVIC
XX Vir
Casetti (2016) confirmed that XX Vir(P=1.348 days) is not a member of the ω Centaurglobular cluster. We agree that XX Vir is an AC, asidentified in Drake et al. (2014a).
UY Eri
The results of the three different articles(Maas et al. 2007, Schmidt et al. 2011, Soubiranet al. 2016) that measured metallicity for UY Eri(P=2.213 days) are summarized in Table 1. Thebig differences in the [Fe/H] values make conclusionsabout this star open for further discussion. While onmost of the Fourier parameter plots UY Eri is amongAC, in amplitude figures (see Figs. 2 and 3) it seemsto be among the BLHs. Further measurements areneeded to resolve the question about the nature ofthis star.
4.2. The short period Type II Cepheids -BL Herculis subtype
Summarizing the results from the Fourier pa-rameter plots we list the BLHs with additional in-formation: positions (RA (h:m:s), DEC (d:m:s),eq=J2000 from Simbad8, the derived median V mag-nitude, and Teff , log g, [Fe/H] from the literature) inTable 2. All, but two, stars had their [Fe/H] de-termined from direct spectroscopic measurements.The exceptions are V527 Sgr (M = 1.025 M¯,R = 1.366 R¯) and V1287 Sco (M = 0.963 M¯,R = 2.933 R¯), for which the parameters were de-rived with a combination of photometric observa-tions and a MW stellar population synthesis program(Sharma et al. 2011) for the EPIC K2 stars (Huberet al. 2016).
There are some BLH stars in our sample thatneed more detailed discussion, which we give in thefollowing paragraphs.
Table 2. The list of BLHs.Name RA (h:m:s) DEC (d:m:s) < V > [mag] P [days] Teff [K] log g
[cgs][Fe/H][dex]
References Notes
BX Del 20:21:18.97 +18:26:16.28 12.412 1.092 6250 1.0 −0.2 Maas et al. (2007)BV Cha 13:02:21.18 −79:45:26.4 12.284 1.238VY Pyx 08:54:29.63 −23:31:18.57 7.245 1.240 5750 1.5 −0.4 Maas et al. (2007)V527 Sgr 19:16:10.99 −20:55:55.8 14.918 1.255 5816 4.159 −0.042 Huber et al. (2016) using Sharma et al. (2011)BL Her 18:01:09.22 +19:14:56.70 10.219 1.307 6121 − − Munoz Bermejo et al. (2013)
6256 − − McDonald et al. (2012)6500 2.0 −0.1 Maas et al. (2007)64976464
− −0.17 Ammons et al. (2006)
6350 2.5 0.0 Caldwell and Butler (1978)V5614 Sgr 17:55:43.81 −29:44:50.2 16.656 1.354HQ CrA 18:11:53.74 −37:39:15.0 14.741 1.415 Madore and Fernie
(1980): blue compan-ion?
KZ Cen 12:01:55.19 −46:16:41.48 12.293 1.520 62616021
− 0.67 Ammons et al. (2006)
V2022 Sgr 18:40:39.0 −25:22:50 13.516 1.529SW Tau 04:24:32.97 +04:07:24.08 9.721 1.584 7036
74826322
3.103.541.92
0.200.220.12
Schmidt et al. (2011)
6250 2.0 0.2 Maas et al. (2007)NW Lyr 19:15:56.34 +34:27:08.08 12.520 1.601VZ Aql 19:05:02.96 −06:50:58.7 14.002 1.685V1437 Sgr 18 03 33.63 −30 01 14.9 15.603 1.748V714 Cyg 19:41:48.62 +37:59:33.8 14.148 1.888RT TrA 16:34:30.89 −63:08:00.81 9.841 1.946 5996
5868− 0.48 Ammons et al. (2006) C-rich
620060406360
2.0 2.52.3
0.340.540.43
Wallerstein et al. (2000)
V439 Oph 17:43:33.27 +03:35:36.08 12.172 1.893 5547.61 −0.493 Luo et al. (2016)GK Cen 13:46:20.94 −49:35:50.1 12.929 1.950V477 Oph 17:59:08.16 +05:38:26.2 13.946 2.016V1287 Sco 16:36:52.85 −28:05:34.2 13.480 2.036 5428 3.542 −0.343 Huber et al. (2016) using Sharma et al. (2011) period increaseAT Tel 18:50:02.64 −51:38:04.6 14.216 1.970V553 Cen 14:46:33.64 −32:10:15.25 8.458 2.061 5600 3.100 −0.500 Soubiran et al. (2016) C-rich
56355654
− 0.16 Ammons et al. (2006)
− − 0.04 Wallerstein and Gonzalez (1996)5600 3.1 −0.5 Wallerstein et al. (1979)
V5608 Sgr 17:54:09.11 −29:39:59.0 16.374 2.212V617 Ara 17:10:08.31 −60:39:43.4 11.792 2.522 DCEP in SimbadV465 Oph 17:52:07.5 −01:05:07 13.312 2.844BE CrA 18:54:54.03 −40:23:15.3 13.957 3.337V5609 Sgr 17:54:55.57 −29:57:31.0 16.919 3.542
8http://simbad.u-strasbg.fr
20
ACs DISCOVERED IN A SAMPLE OF GALACTIC SHORT PERIOD TIICs
BL Her
The literature dealt with BL Her (P=1.307days) in quite some detail. The behaviour of theHα line was analysed by Gillet et al. (1994), whileFokin and Gillet (1994) compared the measurementswith a non-linear model, to find a good agreementand confirmation of the presence of the 2:1 reso-nance predicted by the pulsation model of T2Cs. Theemission in the Hα line was reported in Schmidt etal. (2003) confirming previous findings of Gillet etal. (1994) and Vinko et al. (1998) (and referenceswithin). The numerous measurements of the Teff , logg and [Fe/H] from spectra are listed in Table 2. Fur-thermore, a Baade-Wesselink analysis carried out byBalog et al. (1997) on BL Her gave the following re-sults: R = 9.4 ± 2 R¯. Using the surface-brightnessmethod for deriving radii of stars Arellano Ferro andRosenzweig (2000) derived R = 15.4± 1.5 R¯, whileGroenewegen and Jurkovic (2017b) used the period-radius relation to get R = 8.066 R¯, putting it out-side the region of the BLHs. In the Fourier parame-ters figures the position of BL Her is not unambigu-ous, either. The true nature of BL Her is still openfor discussion, despite the fact that this star namedthe whole subgroup.
KZ Cen
The Fourier parameters and light curve shapeputs KZ Cen (P=1.520 days) among BLHs, but themetallicity given in Table 2 is 0.67, which is too highfor this subtype, so this makes KZ Cen a great can-didate for further spectroscopic measurements.
V2022 Sgr
V2022 Sgr (P=1.529 days) was observed byDiethelm (1983), who found a period of P=1.533days, while Kwee and Diethelm (1984) observed it inUBV-bands determining P=1.533171 days. Proven-cal (1986) has observed that the period has increasedup to P=1.5530160 days.
In Jurkovic (2015) V2022 Sgr was misclassi-fied. The confusion came from the reference on the”The ASAS Catalogue of Variable Stars” which di-rects to this object: 184041-2523.7. This object isindeed a variable star with a period of P=290.71001± 0.52327 days. The right ASAS ID for V2022 Sgr is184039-2523.0, and it appears correctly in the ”ASASAll Star Catalogue”.
We can confirm that V2022 Sgr is a BLH,with a variable period, using data from Kwee andDiethelm (1984).
V1437 Sgr
V1437 Sgr (P=1.748 days) is a probable mem-ber of NGC 6522 (V8) globular cluster accord-ing to the newest catalogue of variables in clustersby Clement (2017) (for details see Clement et al.(2001)). This is also confirmed by Samus et al.(2009b). Udalski et al. (1994) in the VizieR cata-logue (Udalski 1996) provides the OGLE star identi-fier for this object as BWC V1, and gives a type forthe variability: ”ACEP”. It is also remarked thatthis star was identified by Blanco (1984) as a ”CW”and marked V58. The light curve (and I, V mea-surements) can be found in Soszynski et al. (2011b),where it is, once again, classified as a T2C-BLH. Weconfirm this latest result with the Fourier parame-ters.RT TrA
RT TrA (P=1.946 days) is a carbon rich star(Lloyd Evans 1983, Wallerstein et al. 2000, Waller-stein 2002), as is V553 Cen, with a light curve (Di-ethelm 1983) that puts it among BLHs (see Fig. 7a),with a bump on the ascending branch. It looks sim-ilar to a BLH star with a similar period, but thisfeature makes it different. The Fourier parametersR21, R31 are close to 0 (as with the V553 Cen). Theevolutionary models do not give an answer for theexistence of such C-rich stars, as detailed in Waller-stein (2002).
9.2
9.4
9.6
9.8
10
10.2
10.4 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=1.946 days
(a) Phased RT TrA light curve fromASAS-3 data (P=1.946 days).
8.1
8.2
8.3
8.4
8.5
8.6
8.7
8.8
8.9 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=2.061 days
(b) Phased light curve of V553 Cen fromASAS-3 data (P=2.061 days).
Fig. 7. The phased light curves of the C-rich BLH stars.
21
M. I. JURKOVIC
V477 Oph
V477 Oph (P=2.016 days) is a member of theopen cluster Collinder 359 according to (Zejda et al.2012). If it is truly a cluster member this star cannot be a BLH star, because the age of the clusteris much younger (≈ 30-60 × 106 years, see Bobylev(2008)) than any BLH star should be.
V553 CenWallerstein and Gonzales (1996) has con-
firmed from a detailed spectroscopic study that V553Cen (P=2.061 days) is indeed a C- and N- richshort period T2C, and in Wallerstein (1979) pre-sented the measured Teff=5600 K, log g=3.1, and[Fe/H]=−0.50 (see Table 2). It is at the same timean O-poor star, and has a moderate Na content. Theidea of this BLHs star being in a binary system wastested by Wallerstein and Gonzales (1996), but noevidence has been found that would support that.The only strange thing that is different from theother BLHs is that the R21 and R31 parameters arealmost zero, a feature seen in the other C-rich star inthe sample, RT TrA. Fig. 7 shows both RT TrA andV553 Cen showing very similar light curve shapes.
4.3. The (p) W Virginis subtypeType II Cepheids
The peculiar W Virginis (pWVir) stars are aspecial class among the W Virginis (WVir) with pe-riods between 4 and 20 days. Many of the pWVirin the OGLE-III LMC sample are binary systems.They might overlap with the DCEPs on the PL rela-tions, because they are usually brighter than regularWVir stars. The phased light curves of UY CrA andIT Cep are shown in Fig. 8.
UY CrAThe INTEGRAL data of UY CrA (P=6.995
days) is quite noisy, but we could derive theFourier parameters, which puts this star amongDCEP/pWVir stars, although the shape of the lightcurve would support the suggestion that it is morelikely a DCEP.IT Cep
From the Fourier parameters IT Cep(P=7.349 days) can be classified as pWVir. Am-mons et al. (2006) lists Teff=6622 and 6497 K, and[Fe/H]=0.16 [dex].
4.4. Classical Cepheids
Classical Cepheids (DCEPs) are intermediatemass (4-20 M¯) stars pulsating in F, 1O and sec-ond overtone (2O) modes with periods from 1 to 100days (Catelan and Smith 2015). The DCEPs thatwere found during our investigation (combining theFourier parameters, and the light curve shapes) weresummarized in Table 3 (RA (h:m:s), DEC (d:m:s),eq=J2000 from Simbad9, and derived media V mag-nitude). Where available we give the known Teff ,log g and [Fe/H] from spectroscopic measurements,as well as other physical parameters found in litera-ture when describing individual stars.
In the cases of V5626 Sgr (OGLE BUL-SC30604452, OGLE BLG-CEP-25, P=1.33916 days) andV1529 Sco (OGLE BUL-SC4 404186, OGLE BLG-CEP-14, OGLE DIA BUL-SC4 170, P=1.53185days) we relay on the classification given in Soszynskiet al. (2011b) stating that these stars are DCEPs.In the following we provide some details about someof the stars.
13.5
14
14.5
15
15.5
16
16.5
17 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=6.995 days
(a) UY CrA phased with P=6.995 days.
13.3
13.4
13.5
13.6
13.7
13.8
13.9 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=7.349 days
(b) IT Cep phased with P=7.349 days.
Fig. 8. The phased light curves of the suspected pWVir/DCEP stars – UY CrA on the left and IT Cep onthe right.
9http://simbad.u-strasbg.fr
22
ACs DISCOVERED IN A SAMPLE OF GALACTIC SHORT PERIOD TIICs
Table 3. The identified DCEPs among short period BLHs in the GCVS.Name RA (h:m:s) DEC (d:m:s) <V> [mag] P [days] Teff
[K]log g[cgs]
[Fe/H][dex]
References Notes
V351 Cep 22:33:41.35 +57:19:05.89 9.430 2.807DQ And 00:59:34.47 +45:24:24.20 11.715 3.201 6596.19 − 0.418 Luo et al. (2016)
636656656068
2.821.931.79
−0.08−0.40−0.02
Schmidt et al. (2011)
5500 1.5 −0.5 Maas et al. (2007)FM Del 20:33:44.26 +16:16:17.5 13.957 3.337 Le Borgne and
Klotz (2014):DCEP
BD Cas 00:09:51.39 +61:30:50.55 11.110 3.651 62006075
2.50 −0.07 Andrievsky et al.(2013)
− − −0.07 Acharova et al. (2012)606966016278
2.404.701.72
−0.030.02
−0.09
Schmidt et al. (2011)
− − −0.07 Luck et al. (2011)V572 Aql 20:02:32.69 +00:42:50.05 11.207 3.756 6250 1.0 −0.2 Maas et al. (2007)QY Cyg 19:58:51.54 +37:38:50.1 14.645 3.893 Schmidt et al.
(2005): DCEPV383 Cyg 20:28:58.16 +34:08:06.36 10.909 4.612V675 Cen 14:24:50.90 −34:39:45 12.411 4.629 Berdnikov et al.
(2014):DCEPV394 Cep 22:02:40.90 +59:27:09.04 14.008 5.688AB Ara 16:42:08.99 −57:18:44.8 13.355 5.96 ASAS, VSX, Fernie
(1968) and Berd-nikov et al. (2015):DCEP
TX Del 20:50:12.69 +03:39:08.36 9.158 6.166 6217 1.8 0.24 Andrievsky et al.(2013)
− − 0.24 Acharova et al. (2012)57385485
1.321.06
0.230.11
Schmidt et al. (2011)
− − 0.24 Luck et al. (201)5500 0.5 0.1 Maas et al. (2007)55535593
− 0.29 Ammons et al. (2006)
5900 1.6 −0.18 Galazutdinov andKlochkova (1995)
V351 Cep
V351 Cep (P=2.807 days, unclear) is a mem-ber of the galactic open cluster [KPR2005] (Zejda etal. 2012), whose age was approximated to be 0.012× 109 years. Galazutdinov and Klochkova (1995)conclude from their spectroscopic analysis, and tak-ing into account previous photometric analyses, es-pecially from Arellano Ferro (1984), that V351 Cepis not a DCEP, nor is it a T2C, but that it is mostprobably an AC. However, Acharova et al. (2012)calculated the mass and age (as well as [Fe/H]=0.02)of V351 Cep to be 5.1 M¯ and 82 Myr old. Makingthis star too massive to be an AC. Balog et al. (1997)has suspected that V351 Cep is an s-Cepheid whichpulsates in first overtone based on ”small-amplitudesinusoidal light curve, radius as large as about 50-60 R¯, low galactic latitude”.
The V-band data for the Fourier analysis wascollected from Henden (1980) (19 data points) andSzabados (1977) (32 data points). The classificationis not clear. It can be either a BLH or a DCEP, butif it is a BLH then all the other measurements (see
above the mass and radius) are incorrect. In conclu-sion, the true nature of V351 Cep is still open fordiscussion.DQ And
Szabados (1977) analysing the light curve ofDQ And (P=3.201 days) in V says that the presenceof the bump in the descending branch and its highgalactic latitude excludes the possibility that this isa DCEP. In the Schmidt et al. (2005) paper the V-band photometric observations do not show a bumpon the descending branch, so the Szabados (1977)argument does not stand. However, Jurkovic et al.(2016) showed that this star in the span of 12 Gyrshas had a ellipsoidal orbit going from to bellow theGalactic plane. At this present moment it can beseen as a Halo object, but in the case of DQ Andthis does not mean that it is an old low-mass ob-ject. The position of DQ And on the PR relation inGroenewegen and Jurkovic (2017b), using the radiusfrom Balog et al. (1997): R = 35± 6 R¯, as well asthe derived Fourier parameters in this paper, fromthe Schmidt et al. (2005) data, put it among theDCEPs.
23
M. I. JURKOVIC
BD CasAndrievsky et al. (2013) have estimated the
Teff of BD Cas (P=3.651 days) to be 6200 and6075 K. Acharova et al. (2012) derived the follow-ing element abundances from spectroscopic measure-ments: [O/H]=−0.09 and [Fe/H]=−0.07 [dex], fromthe modelling calculated age of BD Cas is 4.9 Myr,and the mass 4.9 M¯. In addition Schmidt et al.(2005) concluded, after much consideration, that BDCas is an overtone pulsator. In our Fourier analysisof the INTEGRAL data we see that the parametersalign with the DCEPs.
TX Del, T2C or DCEP
Here we give an overview of information avail-able about TX Del (P=6.166 days), and while wewould put it among DCEPs, we can not exclude thepossibility that it might be a T2C showing interest-ing features due to it being in a binary. Laney andStobie (1995), Balog and Vinko (1995) and Balog etal. (1997) conclude from the Baade-Wesselink analy-sis that the radius of the star is too big for a T2C, onehas to be careful with this assessment, again, becauseof the presence of a secondary component. Galazut-dinov and Klochkova (1995) presented an extensivespectroscopic analysis and concluded that it showsall the hallmark of a classical Cepheid, but becauseof the binary nature and a possible interaction be-tween the components. The automated classificationof the Hipparcos variables (Dubath et al. 2011) hasit as ”DCEP”. Acharova et al. (2012) has the massestimate at M = 6.4 M¯, and age 60 Myr, makingit impossible to be a T2C. Maas et al. (2007) pointsto Andrievsky et al. (2002) to say that this is afirst-overtone Type I Cepheid, and it is clear from itschemical element abundance that it has gone througha mass transfer, nevertheless the authors stay with aconclusion that TX Del is a T2C.
5. STARS IN THE SAMPLE THAT ARENOT PULSATING VARIABLES
NY HerNY Her (P=0.076 days) is a SU UMa type
dwarf nova as it was described in Kato et al. (2013).We confirm their findings on the AAVSO dataset ofNY Her as shown in Fig. 9a.V4110 Sgr
Fig. 9b shows our analysis of the OGLE I-band data of V4110 Sgr (P=1.125 days). The periodthat we found was P=1.1254 days. It has a strangejump in amplitude, which comes back to the previouslevel. It would be highly unlikely for a pulsating starto show such a behaviour, if it was real. This feature,on the other hand, could be a result of a measure-ment error, so we can not give a definite conclusion.Another thing to notice is that V4110 Sgr is flaggedto be in a crowded field, and a neighbouring star
OGLEII DIA BUL-SC01 V3246 (RA: 270.757455,DEC: - 29.766070, and the median I-band magnitudeis 15.899 ± 0.047 mag) is a BY Draconis variablestype of variable star (rotating stars with star spots,and other chromospheric activity). Blanco (1984)has V4110 Sgr observed from 1977 to 1981 (it wasoriginally classified as a CW star by Gaposchkin),and it showed a variable period (in 1977 P=1.1247,in 1979 P=1.1345, and in 1980 P=1.108 days).
CT Sge
CT Sge (PGCVS=1.7179 days) has the V-banddata in the ASAS catalogue, but the period givenby the GCVS team, P=1.7179 days, and the periodfrom the Fourier analysis does not phase the lightcurve. We were not able to phase the light curve us-ing the above periods, nor could we establish a newone from the Fourier analysis.
DI AndDI And (PGCV S=3.385584882 days) was orig-
inally classified in the GCVS as an ”IS” star, whichchanged to ”CWB:” after Khruslov (2005) publishedits results, noting that ”the shape of the descendingbranch is not quite typical”. WASP has a long dataset, which we looked at (see Fig. 9c). We are notaware of any known T2C nor DCEP of this periodto have an even remotely similar light curve shape.Morrison et al. (2001) gives us the information thatit is not a binary. The possible types of variabilitythat could result in a similar light curve shape couldbe a star with spots, a chromospherically active staror a rotating star.UW For
UW For (PASAS=4.277943728 days) is aneclipsing binary system, as it was described by theASAS with the period of P=4.27774 days.
The phased light curve (see Fig. 9d) showstwo minima in the eclipse. We do not exclude thepossibility that after removing the eclipse from thelight curve there could be other variability left in thesystem.KT Com
KT Com (PASAS=8.140512308 days) is listedas a semi-detached (ESD) or detached (ED) bi-nary system. Using this classification Szczygiel etal. (2008) have calculated the bolometric luminosityL=33.418 erg/s, X-ray luminosity LX=29.765 erg/s,and distance d=39.1256 pc. Independently Soubiranet al. (2016) give an effective temperature Teff=5924K for this star. In the ”The International VariableStar Index” (VSX) of the The American Associationof Variable Star Observers (AAVSO)10 KT Com isa variable star of the RS Canum Venaticorum-typebinary system, with the period of P=4.07 days, butthe given reference Kiraga (2012) lists this star asa rotation variable. We conclude that KT Com isnot a BLH, but instead it is most probably a binarysystem.
10http://www.aavso.org/vsx/
24
ACs DISCOVERED IN A SAMPLE OF GALACTIC SHORT PERIOD TIICs
15.2
15.4
15.6
15.8
16
16.2
16.4
16.6 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=0.076 days
(a) NY Her phased with P=0.076 daysfrom the AAVSO data.
16
16.5
17
17.5
18
18.5 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
I (m
ag)
Phase
P=1.125 days
(b) V4110 Sgr OGLE II I-band phasedlight curve with P=1.125 days.
12
12.1
12.2
12.3
12.4
12.5
12.6
12.7
12.8 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
mag
Phase
P=3.386 days
(c) DI And phased light curve fromSuperWASP data with P=3.386 days.
11
11.2
11.4
11.6
11.8
12
12.2
12.4 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=4.278 days
(d) UW For phased light curve withP=4.278 days using ASAS-3 data.
8.1
8.2
8.3
8.4
8.5
8.6
8.7
8.8
8.9 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
V (
mag
)
Phase
P=8.141 days
(e) KT Com phased light curve withperiod P=8.141 days using ASAS-3 data.
Fig. 9. Stars that are not pulsating variables.
25
M. I. JURKOVIC
V403 Cyg
Koch (1974) listed V403 Cyg (no period) as astrong interacting binary, but there is no light curvethat would support this claim. The GCVS listedSuzuki and Huruhata (1938) for the identification,and it is listed as a binary in Coughlin et al. (2014),yet again there were no data to support it. Super-WASP has a lot of data points, but it does not showany sign of binarity and it can not be phased withthe given period of PGCVS=0.80477 days. This is tooshort for a BLH, but it is in the range of ACs. Takeninto account that Hanson et al. (2004) have classi-fied it as an RRL, it is very possible that, indeed, itis an AC, but further observations would be neededto confirm this claim. We could not determine whatkind of variable this star is.
6. THE DISCUSSION OF METALLICITY
The collected spectroscopic data of the pub-lished Teff , log g, and [Fe/H] confirms the re-sult from Diethelm (1990) described in Wallerstein(2002), about the metallicities. Diethelm (1990)has estimated the photometric metallicities of thethan known short period T2Cs, and it became ob-vious that from the 45 stars in his list, 30 had[Fe/H]VBLU > −0.3, and 8 had [Fe/H]VBLU < −1.0.Comparing our list of AC with these results we sawthat 7 out of 8 were indeed AC. The metallicitiesthat are in Tables 1 and 2 are directly measuredfrom spectra, and they also show the same distri-bution of [Fe/H]. In the case of the ACs we haveonly data for 4 stars, and they are very metal poor.The average of all the eight measurements of 4 starsis <[Fe/H]>=−1.12 dex, but if we leave out the out-lier of UY Eri by Schmidt et al. (2011) then theit becomes <[Fe/H]>=−1.88 dex. While the num-ber of measured metallicities is small, we do suggestthat it is correct to conclude that this low metallic-ity is fundamental to the evolution of these objects.This was already known from observations in dwarfspherical and dwarf irregular galaxies (for example
Sculptor, Sextans, LeoII, Ursa Minor, Draco, For-nax, LeoI) and in smaller numbers in globular clus-ters, such as BL Boo in NGC 5466, and in the MilkyWay summarized in Fiorentino and Monelli (2012).Bono (1997b) and Fiorentino and Monelli (2012), aswell as others, have used these observational bound-aries to constrain their theoretical calculations con-firming that ACs are metal-poor stars with an meanmass of 1.2 − 1.5 M¯.
The BLH stars, on the other hand, turnedout to have Solar metallicities on average,<[Fe/H]>=0.00 dex. We got this by combiningall 21 measurements of 10 stars. BLHs are not metalpoor, despite being old objects.
In order to see how these results reflect onthe Herztsprung-Russell diagram (HRD) of the BLHstars in the MW we have calculated the luminosities(L) from the Groenewegen and Jurkovic (2017b). Weused the Mbol=0.12−1.78 log P formula to calculatethe bolometric magnitudes, and than we convertedthat to luminosities. The Teff values are given inTable 2, which were measured from spectroscopy. Inthe cases where there were multiple measurementsfor Teff we have used the mean value of all the values.In the same table we give the values of pulsational pe-riods in days, derived from our Fourier analysis. Thenumber of BLH stars was limited to 10 stars, sinceonly for these the spectroscopy was available, and wegive all the relevant data in Table 4. In Fig. 10 wehave compared our computed L and Teff with modelsof the horizontal branch (HB) stars from the BaSTI11evolutionary model database. The models were cal-culated for the Solar metallicity of [M/H]=0.058 tomatch our findings, and previously assumed metal-licity value for metal-poor stars of [M/H]=−1.488.Masses of the modelled stars were M = 0.500 M¯,M = 0.520 M¯, M = 0.530 M¯ and M = 0.550 M¯.These mass ranges are in agreement with estimatesfrom Bono (1997a) of approx. 0.52 − 0.53 M¯ andGroenewegen and Jurkovic (2017a) of 0.49 M¯. Allof our stars fall in the region of Solar metallicitymodels, with the majority being on the track for theM = 0.500 M¯ model, and going towards the track
Table 4. The mean effective temperature (< Teff >) from spectroscopic measurements shown in Table 2,the pulsational period (P ), the bolometric magnitude form Mbol = 0.12 − 1.78 log P (Groenewegen andJurkovic 2017b), and the calculated luminosities (L) for the Galactic BLH stars.
Name < Teff > (K) log < Teff > (K) P (days) log P (days) Mbol (mag) L (L¯) log L (L¯)BX Del 6250 3.796 1.092 0.038 0.052 75.03 1.87VY Pyx 5750 3.760 1.240 0.093 −0.046 82.13 1.91V527 Sgr 5816 3.765 1.255 0.099 −0.056 82.84 1.92KZ Cen 6141 3.788 1.520 0.182 −0.204 94.94 1.98SW Tau 6772.5 3.831 1.584 0.200 −0.236 97.77 1.99V439 Oph 5547 3.744 1.893 0.277 −0.373 111.00 2.05V1287 Sco 5428 3.735 2.036 0.309 −0.430 116.91 2.08V553 Cen 5629.7 3.750 2.061 0.314 −0.440 117.93 2.07RT TrA 6092.8 3.785 1.946 0.289 −0.395 113.21 2.05BL Her 6364.7 3.804 1.307 0.116 −0.087 85.27 1.931
11http://basti.oa-teramo.inaf.it/
26
ACs DISCOVERED IN A SAMPLE OF GALACTIC SHORT PERIOD TIICs
1
1.5
2
2.5
3
3.5
4
4.5
3.43.63.844.24.44.6
Log
(LL
SU
N)
Log Teff (K)
[M/H]=-1.488, M=0.500 MSUN[M/H]=-1.488, M=0.520 MSUN[M/H]=-1.488, M=0.530 MSUN[M/H]=-1.488, M=0.550 MSUN[M/H]=0.058, M=0.500 MSUN[M/H]=0.058, M=0.520 MSUN[M/H]=0.058, M=0.530 MSUN[M/H]=0.058, M=0.550 MSUN
BLH stars in the MW
Fig. 10. The BLH stars from MW plotted with metal-poor and Solar metallicity models. The modelsare from the BaSTI database (Pietrinferni et al. 2004). The black circles represent data for the BLHstars shown in Table 4. In the case of the metal-poor models ([M/H] = −1.488) the masses are shown withthe following colors and symbols: red plus signs M = 0.500 M�, green crosses M = 0.520 M�, blue starM = 0.530 M�, and pink doted square M = 0.550 M�. For the Solar metallicity models ([M/H] = 0.058) themasses are shown as: cyan square M = 0.500 M�, yellow dotted circle M = 0.520 M�, grey filled triangleM = 0.530 M�, orange dotted triangle M = 0.550 M�.
of the M = 0.520 M� model. The metal-poor modelof M = 0.550 M� is very close to the Solar metallic-ity model of M = 0.500 M�, but the independentlymeasured spectroscopic metallicities as well as thenewest mass estimates seem to strengthen our find-ing that the BLH stars have Solar-like metallicities.
7. CONCLUSIONS
Fourier parameters of 59 stars from the GCVSshort period T2Cs list, known as BLHs, as well as33 BLHs and 29 ACs from the LMC OGLE-III cat-alogue for comparison, using the V-band datasets,were derived. Among the 59 stars we have found19 F ACs, 1 1O AC, 26 BLHs, 2 pWVir/DCEP, 11DCEPs, and 7 other types of variables.
The BLHs and ACs can be distinguished usingthe R21, R31 and φ31 Fourier parameters. The φ21parameter is not useful for this purpose, because al-most all the points clumped together. Figs. 2 and 3show log P vs. 2×Af0 and 3×Af0, respectively, andon them ACs are more clearly separated from BLHsthan on the other Fourier parameter plots. TheseFourier parameters can be used as new comparisonsample for stars measured by the Kepler space tele-scope, since its broad band filter corresponds broadlywith the V-band.
In total 19 F ACs and one 1O AC were dis-covered in the examined sample. FY Vir, V563 Cen,V716 Oph, BF Ser, BI Tel, VX Cap, XX Vir, andV1149 Her were detected as ACs in the CSS (Drakeet al. 2014a, 2017) using a different method of de-tection, and we confirmed their classification throughthe Fourier parameters. We add further 12 F ACs(FY Aqr, PP Tel, DF Hyi, BQ CrA, BH Cet, V2733Oph, CE Her, MQ Aql, V745 Oph, UY Eri, UX Nor),and one 1O AC (V742 Cyg) to the previously knownones. We list some of our findings:(i) V742 Cyg is a 1O AC, and a supposed member
of the Dolidze 37 open cluster, making it the firstobjects of this type to be discovered in an opencluster, but further observations would be neededto confirm this result;
(ii) FY Vir shows signs of Blazhko effect-like modu-lation.
BLHs stars are shown to have Solar-like metal-licities if the AC are properly separated from thesample. The AC, despite being more massive, seemto have low-metallicities.
These results can also be useful for other re-search fields, such as Galactic archaeology and evolu-tion modelling, as well for individual measurementsof these objects, and for the improvement of the pre-cision of the PL relation, as it will become even moreimportant with the new Gaia data (Gaia Collabora-tion 2016).
27
M. I. JURKOVIC
Acknowledgements – I would like to express my deep-est gratitude to G. B., Martin Groenewegen, RobertSzabo, Emese Plachy, Branislav Vukotic, LaszloMolnar, and all the colleagues with whom I have con-sulted for all their help and patience. This researchis financially supported by the Ministry of Educa-tion, Science and Technological Development of theRepublic of Serbia through the project 176004. Thisproject has been supported by the NKFIH K-115709grant of the Hungarian National Research, Develop-ment and Innovation Office. This research has madeuse of NASA’s Astrophysics Data System. Thisresearch has made use of the SIMBAD database,operated at CDS, Strasbourg, France (Wenger et al.2000). Based on data from the OMC Archive at CAB(INTA-CSIC), pre-processed by ISDC. The CSS sur-vey is funded by the National Aeronautics and SpaceAdministration under Grant No. NNG05GF22G is-sued through the Science Mission Directorate Near-Earth Objects Observations Program. The CRTSsurvey is supported by the U.S. National ScienceFoundation under grants AST-0909182. This re-search has made use of the NASA/ IPAC InfraredScience Archive, which is operated by the Jet Propul-sion Laboratory, California Institute of Technology,under contract with the National Aeronautics andSpace Administration. This work has made useof data from the European Space Agency (ESA)mission Gaia (https://www.cosmos.esa.int/gaia),processed by the Gaia Data Processingand Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium).Funding for the DPAC has been provided by na-tional institutions, in particular the institutions par-ticipating in the Gaia Multilateral Agreement.
REFERENCES
Acharova, I. A., Mishurov, Y. N. and Kovtyukh, V.V.: 2012, Mon. Not. R. Astron. Soc., 420,1590.
Allende Prieto, C., Rebolo, R., Garcıa Lopez, R. J.et al.: 2000, Astron. J., 120, 1516.
Ammons, S. M., Robinson, S. E., Strader, J. et al.:2006, Astrophys. J., 638, 1004.
Andrievsky, S. M., Kovtyukh, V. V., Luck, R. E. etal.: 2002, Astron. Astrophys, 381, 32.
Andrievsky, S. M., Lepine, J. R. D., Korotin, S. A.et al.: 2013, Mon. Not. R. Astron. Soc., 428,3252.
Arellano Ferro, A.: 1984, Mon. Not. R. Astron.Soc., 209, 481.
Arellano Ferro, A. and Rosenzweig, P.: 2000, Mon.Not. R. Astron. Soc., 315, 296.
Balog, Z. and Vinko, J.: 1995, Inf. Bull. Var. Stars,4150.
Balog, Z., Vinko, J. and Kaszas, G.: 1997, Astron.J., 113, 1833.
Berdnikov, L. N.: 2008, VizieR Online Data Catalog,2285: Photoelectric observations of Cepheidsin UBV(RI)c.
Berdnikov, L. N., Kniazev, A. Y., Sefako, R.,Kravtsov, V. V. and Zhujko, S. V.: 2014, As-tron. Lett., 40, 125.
Berdnikov, L. N., Kniazev, A. Y., Sefako, R. et al.:2015, Astron. Lett., 41, 23.
Blanco, B. M.: 1984, Astron. J., 89, 1836.Bobylev, V. V.: 2008, Astron. Lett., 34, 686.Bono, G., Caputo, F. and Santolamazza, P.: 1997a,
Astron. Astrophys, 317, 171.Bono, G., Caputo, F., Santolamazza, P., Cassisi, S.
and Piersimoni, A.: 1997b, Astron. J., 113,2209.
Caldwell, C. N. and Butler, D.: 1978, Astron. J.,83, 1190.
Casetti, D.: 2016, private communication.Catelan, M. and Smith, H. A.: 2015, Pulsating Stars,
Wiley-VCH Verlag GmbH and Co., Weinheim.Clement, C. M., Muzzin, A., Dufton, Q. et al.: 2001,
Astron. J., 122, 2587.Clement, C. M.: 2017, VizieR Online Data Cata-
log, 5150: Updated catalog of variable stars inglobular clusters.
Coughlin, J. L., Thompson, S. E., Bryson, S. T. etal.: 2014, Astron. J., 147, 119.
Diethelm, R.: 1983, Astron. Astrophys, 124, 108.Diethelm, R.: 1990, Astron. Astrophys, 239, 186.Dinescu, D. I.: 2002, ASP Conf. Ser., 265, 365.Drake, A. J., Djorgovski, S. G., Mahabal, A. et al.:
2009, Astrophys. J., 696, 870.Drake, A. J., Graham, M. J., Djorgovski, S. G. et
al.: 2014a, Astrophys. J. Suppl. Ser., 213, 9.Drake, A. J., Graham, M. J., Djorgovski, S. G.
et al.: 2014b, VizieR Online Data Cata-log, J/ApJS/213/9: Catalina Surveys periodicvariable stars.
Drake, A. J., Djorgovski, S. G., Catelan, M. et al.:2017, Mon. Not. R. Astron. Soc., 469, 3688.
Dubath, P., Rimoldini, L., Sveges, M. et al.: 2011,Mon. Not. R. Astron. Soc., 414, 2602.
Fernie, J. D.: 1968, Astron. J., 73, 995.Fiorentino, G., Limongi, M., Caputo, F. and Mar-
coni, M.: 2006, Astron. Astrophys, 460, 155.Fiorentino, G. and Monelli, M.: 2012, Astron. As-
trophys, 540, A102.Fokin, A. B. and Gillet, D.: 1994, Astron. Astrophys,
290, 875.Gaia Collaboration, Prusti, T., de Bruijne, J. H. J.
et al.: 2016, Astron. Astrophys, 595, A1.Galazutdinov, G. A. and Klochkova, V. G.: 1995,
Astron. Astrophys. Trans., 8, 227.Gillet, D., Burki, G., Chatel, A., Duquennoy, A. and
Lebre, A.: 1994, Astron. Astrophys, 286, 508.Groenewegen, M. A. T. and Jurkovic, M. I.: 2017a,
Astron. Astrophys, 603, A70.Groenewegen, M. A. T. and Jurkovic, M. I.: 2017b,
Astron. Astrophys, 604, A29.Hanson, R. B., Klemola, A. R., Jones, B. F. and
Monet, D. G.: 2004, Astron. J., 128, 1430.Harris, H. C.: 1981, Astron. J., 86, 719.Henden, A. A.: 1980, Mon. Not. R. Astron. Soc.,
192, 621.Huber, D., Bryson, S. T., Haas, M. R. et al.: 2016,
Astrophys. J. Suppl. Ser., 224, 2.Jurkovic, M. and Szabados, L.: 2014, IAU Symp.,
301, 431.Jurkovic, M. I.: 2015, European Physical Journal
Web of Conferences, 101, 06035.Jurkovic, M. I., Stojanovic, M. and Ninkovic, S.:
2016, Commmunications of the Konkoly Ob-servatory Hungary, 105, 175.
Kato, T., Hambsch, F.-J., Maehara, H. et al.: 2013,Publ. Astron. Soc. Jpn., 65, 23.
28
ACs DISCOVERED IN A SAMPLE OF GALACTIC SHORT PERIOD TIICs
Khruslov, A. V.: 2005, Peremennye Zvezdy Prilozhe-nie, 5.
Kiraga, M.: 2012, Acta Astron., 62, 67.Koch, R. H.: 1974, Astron. J., 79, 34.Kwee, K. K. and Diethelm, R.: 1984, Astron. Astro-
phys, 55, 77.Laney, C. D. and Stobie, R. S.: 1995, Mon. Not. R.
Astron. Soc., 274, 337.Layden, A. C.: 1994, Astron. J., 108, 1016.Le Borgne, J. F. and Klotz, A.: 2014,
arXiv:1407.4961.Lenz, P. and Breger, M.: 2004, IAU Symp., 224,
786790.Lloyd Evans, T.: 1983, Observatory, 103, 276.Luck, R. E., Andrievsky, S. M., Kovtyukh, V. V.,
Gieren, W. and Graczyk, D.: 2011, Astron.J., 142, 51.
Luo, A.-L., Zhao, Y.-H., Zhao, G. et al.: 2016,VizieR Online Data Catalog, 5149: LAMOSTDR2 catalogs.
Maas, T., Giridhar, S. and Lambert, D. L.: 2007,Astrophys. J., 666, 378.
Madore, B. F. and Fernie, J. D.: 1980, Publ. Astron.Soc. Pac., 92, 315.
McCarthy, J. K. and Nemec, J. M.: 1997, Astrophys.J., 482, 203.
McDonald, I., Zijlstra, A. A. and Boyer, M. L.: 2012,Mon. Not. R. Astron. Soc., 427, 343.
Morrison, J. E., Roser, S., McLean, B., Bucciarelli,B. and Lasker, B.: 2001, Astron. J., 121,1752.
Munoz Bermejo, J., Asensio Ramos, A. and AllendePrieto, C.: 2013, Astron. Astrophys, 553,A95.
Nemec, J. and McCarthy, J. K.: 1998, ASP Conf.Ser., 135, 57.
Petersen, J. O. and Diethelm, R.: 1986, Astron. As-trophys, 156, 337.
Pojmanski, G.: 1997, Acta Astron., 47, 467.Pojmanski, G., Pilecki, B. and Szczygiel, D.: 2005,
Acta Astron., 55, 275.Provencal, J.: 1986, Journal of the American Asso-
ciation of Variable Star Observers, 15, 36.Richards, J. W., Starr, D. L., Miller, A. A. et al.:
2012, Astrophys. J. Suppl. Ser., 203, 32.Samus, N. N., Durlevich, O. V. et al.: 2009a, VizieR
Online Data Catalog, J/PASP/121/1378: Po-sitions of variable stars in globular clusters.
Samus, N. N., Kazarovets, E. V., Pastukhova, E.N., Tsvetkova, T. M. and Durlevich, O. V.:2009b, Publ. Astron. Soc. Pac., 121, 1378.
Samus, N. N., Kazarovets, E. V., Durlevich, O. V.,Kireeva, N. N. and Pastukhova, E. N.: 2017,Astron. Rep., 61, 80.
Schmidt, E. G., Loomis, C. G., Groebner, A. T. andPotter, C. T.: 1990, Astrophys. J., 360, 604.
Schmidt, E. G.: 1991, Astron. J., 102, 1766.Schmidt, E. G. and Reiswig, D. E.: 1993, Astron. J.,
106, 2429.Schmidt, E. G., Lee, K. M., Johnston, D., Newman,
P. R. and Snedden, S. A.: 2003, Astron. J.,126, 906.
Schmidt, E. G., Johnston, D., Langan, S. and Lee,K. M.: 2005, Astron. J., 130, 832.
Schmidt, E. G., Rogalla, D. and Thacker-Lynn, L.:2011, Astron. J., 141, 53.
Sharma, S., Bland-Hawthorn, J., Johnston, K. V.and Binney, J.: 2011, Astrophys. J., 730, 3.
Simon, N. R. and Lee, A. S.: 1981, Astrophys. J.,248, 291.
Soszynski, I., Udalski, A., Szymanski, M. K. et al.:2008, Acta Astron., 58, 293.
Soszynski, I., Poleski, R., Udalski, A. et al.: 2010a,Acta Astron., 60, 17.
Soszynski, I., Udalski, A., Szymanski, M. K. et al.:2010b, Acta Astron., 60, 91.
Soszynski, I., Dziembowski, W. A., Udalski, A. etal.: 2011a, Acta Astron., 61, 1.
Soszynski, I., Udalski, A., Pietrukowicz, P. et al.:2011b, Acta Astron., 61, 285.
Soszynski, I., Udalski, A., Szymanski, M. K. et al.:2017, arXiv:1712.01307.
Soubiran, C., Le Campion, J.-F., Brouillet, N. andChemin, L.: 2016, Astron. Astrophys, 591,A118.
Suzuki, K. and Huruhata, M.: 1938, Astron. Nachr.,267, 101.
Szabados, L.: 1977, Commmunications of theKonkoly Observatory Hungary, 70, 1.
Szabados, L., Kiss, L. L. and Derekas, A.: 2007, As-tron. Astrophys, 461, 613.
SzczygieÃl, D. M., Socrates, A., Paczynski, B., Po-jmanski, G. and Pilecki, B.: 2008, Acta As-tron., 58, 405.
Udalski, A., Kubiak, M., Szymanski, M. et al.: 1994,Acta Astron., 44, 317.
Udalski, A.: 1996, VizieR Online Data Catalog,II/213/pvar: OGLE Galactic Bulge periodicvariables.
Vasil’Yanovskaya, O. P.: 1978, Peremennye Zvezdy,21, 111.
Vinko, J., Remage Evans, N., Kiss, L. L. and Szaba-dos, L.: 1998, Mon. Not. R. Astron. Soc.,296, 824.
Wallerstein, G., Brown, J. A. and Bates, B. A.: 1979,Publ. Astron. Soc. Pac., 91, 47.
Wallerstein, G. and Gonzalez, G.: 1996, Mon. Not.R. Astron. Soc., 282, 1236.
Wallerstein, G., Matt, S. and Gonzalez, G.: 2000,Mon. Not. R. Astron. Soc., 311, 414.
Wallerstein, G.: 2002, Publ. Astron. Soc. Pac., 114,689.
Wenger, M., Ochsenbein, F., Egret, D. et al.: 2000,Astron. Astrophys Suppl. Ser., 143, 9.
Zejda, M., Paunzen, E., Baumann, B., Mikulasek, Z.and Liska, J.: 2012, Astron. Astrophys, 548,A97.
Zinn, R. and Dahn, C. C.: 1976, Astron. J., 81, 527.
APPENDIX
In Tables A1, A2 and A3 we give the Fourierparameters of the investigated stars in the MilkyWay, the Fourier parameters of the ACs in the LMCusing the V-band data from the OGLE-III surveyand the Fourier parameters of the BLHs in the LMCusing the V-band data from the OGLE-III survey,respectively.
29
M. I. JURKOVICTab
leA
.1.
The
Four
ier
para
met
ers
ofth
ein
vest
igat
edst
ars
inth
eM
ilky
Way
.N
ame
f 0lo
gP
[day
s]A
1A
1err
A2
A2err
A3
A3err
R21
R21err
R31
R31err
φ1
φ1err
φ2
φ2err
φ3
φ3err
φ21
φ21err
φ31
φ31err
Sour
ceV
742
Cyg
1.06
7850
11−0
.028
5102
967
0.33
0.01
0.12
0.01
0.04
0.01
0.36
0.04
0.12
0.04
0.61
30.
005
0.77
0.02
0.78
0.16
4.97
0.02
2.74
0.16
Schm
idt
and
Rei
swig
(199
3)FY
Aqr
0.97
7620
241
0.00
9829
8152
0.28
70.
005
0.11
80.
005
0.09
10.
005
0.41
0.02
0.32
0.02
0.75
10.
003
0.87
30.
007
0.00
90.
009
3.89
60.
007
1.60
50.
009
Poj
man
ski(1
997)
V56
3C
en0.
9285
7709
80.
0321
8203
180.
437
0.00
70.
206
0.00
80.
153
0.00
70.
470.
020.
350.
020.
621
0.00
30.
635
0.00
60.
666
0.00
94.
043
0.00
71.
914
0.00
9D
rake
etal
.(2
014a
)FY
Vir
0.92
4247
177
0.03
4211
8673
0.40
40.
006
0.17
40.
007
0.15
40.
007
0.43
0.02
0.38
0.02
0.37
80.
003
0.15
50.
006
0.90
90.
007
4.07
60.
007
1.72
80.
008
Dra
keet
al.
(201
4a)
PP
Tel
0.91
6880
399
0.03
7687
3115
0.36
0.02
0.20
0.02
0.14
0.02
0.55
0.07
0.40
0.06
0.84
10.
009
0.10
0.02
0.30
0.02
4.19
0.02
1.74
0.03
Poj
man
ski(1
997)
BX
Del
0.91
5927
138
0.03
8139
0731
0.35
90.
007
0.12
0.02
0.06
40.
006
0.35
0.06
0.18
0.02
0.72
70.
003
0.96
0.07
0.98
0.03
4.77
0.07
1.87
0.03
Poj
man
ski(1
997)
V71
6O
ph0.
8961
2474
90.
0476
3152
820.
491
0.00
80.
231
0.00
50.
161
0.00
40.
470.
010.
329
0.00
90.
579
0.00
20.
541
0.00
20.
529
0.00
43.
984
0.00
31.
841
0.00
5Poj
man
ski(1
997)
DF
Hyi
0.89
0678
094
0.05
0279
2289
0.51
0.03
0.28
0.03
0.17
0.05
0.55
0.07
0.33
0.09
0.85
20.
009
0.01
0.02
0.27
0.17
3.52
0.02
1.38
0.17
Poj
man
ski(1
997)
BQ
CrA
0.89
8867
5175
90.
0521
9794
140.
270.
040.
210.
040.
160.
040.
770.
190.
590.
160.
410.
030.
190.
060.
810.
083.
910.
070.
460.
08Poj
man
ski(1
997)
BH
Cet
0.87
8962
235
0.05
6029
7842
0.42
00.
004
0.19
80.
004
0.13
60.
004
0.47
0.01
0.32
30.
009
0.14
50.
001
0.67
90.
003
0.22
90.
005
4.01
90.
003
1.85
40.
005
Dra
keet
al.
(201
4a)
BF
Ser
0.85
8045
833
0.06
6489
5134
0.48
20.
006
0.24
50.
006
0.16
20.
006
0.51
0.01
0.34
0.01
0.31
20.
002
0.03
90.
004
0.79
00.
006
4.18
60.
004
2.23
30.
006
Poj
man
ski(1
997)
BI
Tel
0.85
7323
302
0.06
6860
4377
0.47
20.
007
0.23
80.
007
0.14
80.
007
0.50
0.02
0.31
0.02
0.77
60.
002
0.95
00.
005
0.13
90.
008
4.06
60.
005
1.94
70.
008
Poj
man
ski(1
997)
V27
33O
ph0.
8535
5494
30.
0687
6851
830.
600.
040.
250.
050.
090.
030.
420.
090.
150.
050.
780.
010.
990.
060.
150.
244.
280.
061.
980.
24Poj
man
ski(1
997)
CE
Her
0.82
6825
468
0.08
2586
1546
0.37
0.01
0.18
0.01
0.14
0.01
0.48
0.04
0.38
0.04
0.87
50.
006
0.49
0.01
0.48
0.01
6.22
0.01
2.26
0.01
Poj
man
ski(1
997)
BV
Cha
0.80
7728
303
0.09
2734
6991
0.38
00.
002
0.13
90.
003
0.10
60.
002
0.36
50.
008
0.27
90.
007
0.85
10.
001
0.20
50.
003
0.46
80.
005
4.73
10.
003
2.60
80.
005
Poj
man
ski(1
997)
VY
Pyx
0.80
6485
292
0.09
3403
5485
0.11
80.
001
0.01
90.
001
0.00
50.
001
0.16
0.01
0.04
0.01
0.65
50.
002
0.85
0.01
0.45
0.22
4.97
0.01
6.16
0.22
Poj
man
ski(1
997)
V52
7Sg
r0.
7970
3542
20.
0985
2237
720.
360.
010.
120.
020.
030.
010.
320.
050.
080.
040.
949
0.00
60.
320.
020.
420.
044.
250.
020.
460.
04K
wee
and
Die
thel
m(1
984)
BL
Her
0.76
4852
872
0.11
6422
0982
0.34
20.
002
0.12
10.
002
0.08
20.
002
0.35
30.
006
0.24
10.
007
0.79
80.
001
0.10
10.
003
0.40
80.
004
4.74
00.
003
3.22
30.
004
Poj
man
ski(1
997)
VX
Cap
0.75
0502
164
0.12
4648
0512
0.47
90.
005
0.22
70.
005
0.13
00.
005
0.47
0.01
0.27
0.01
0.22
20.
002
0.89
10.
003
0.53
10.
006
4.44
60.
004
2.39
30.
007
Dra
keet
al.
(201
4a)
V56
14Sg
r0.
7384
9021
30.
1316
5525
590.
310.
010.
120.
010.
070.
010.
370.
040.
220.
040.
898
0.00
50.
340.
010.
790.
024.
960.
023.
740.
02So
szyn
skiet
al.
(201
1b)
XX
Vir
0.74
1726
923
0.12
9755
9568
0.39
20.
006
0.19
30.
006
0.13
20.
006
0.49
0.02
0.34
0.02
0.46
50.
002
0.34
30.
005
0.24
80.
007
4.16
30.
005
2.21
50.
007
Poj
man
ski(1
997)
V11
49H
er0.
7094
2442
70.
1409
3861
90.
336
0.00
40.
173
0.00
40.
123
0.00
40.
514
0.01
260.
370.
010.
481
0.00
20.
392
0.00
30.
317
0.00
54.
274
0.00
42.
356
0.00
5D
rake
etal
.(2
014a
)H
QC
rA0.
7064
8572
20.
1508
9661
080.
390.
020.
120.
010.
010.
010.
310.
040.
030.
030.
040
0.00
60.
430.
020.
690.
193.
790.
020.
430.
19K
wee
and
Die
thel
m(1
984)
MQ
Aql
0.67
5328
868
0.17
0484
6853
0.29
0.02
0.18
0.02
0.17
0.02
0.64
0.10
0.59
0.09
0.21
0.01
0.75
0.02
0.46
0.02
3.58
0.03
2.01
0.03
Poj
man
ski(1
997)
KZ
Cen
0.65
7879
317
0.18
1853
7671
0.38
40.
004
0.14
40.
005
0.05
30.
004
0.38
0.01
0.14
0.01
0.31
10.
002
0.99
10.
005
0.46
0.01
3.88
10.
000.
150.
01Poj
man
ski(1
997)
V20
22Sg
r0.
6538
2010
80.
1845
4172
70.
380.
010.
140.
080.
050.
080.
370.
210.
130.
200.
952
0.00
60.
540.
010.
600.
145.
590.
021.
560.
14K
wee
and
Die
thel
m(1
984)
SWTau
0.63
1499
487
0.19
9626
9979
0.35
30.
004
0.11
50.
004
0.03
050.
004
0.33
0.01
0.09
0.01
0.02
60.
002
0.51
50.
005
0.15
0.02
4.47
40.
005
3.58
40.
020
Poj
man
ski(1
997)
V74
5O
ph0.
6264
9732
30.
2030
8078
040.
250.
020.
090.
030.
050.
020.
370.
120.
180.
070.
420.
010.
270.
250.
340.
074.
180.
253.
580.
07Poj
man
ski(1
997)
NW
Lyr
0.62
4493
109
0.20
4472
3495
0.40
0.03
0.16
0.03
0.08
0.03
0.40
0.07
0.20
0.07
0.89
00.
010
0.29
0.02
0.42
0.06
4.75
0.03
1.54
0.06
Schm
idt
etal
.(2
005)
V97
1A
ql0.
6155
5747
30.
2107
3139
190.
363
0.00
50.
091
0.00
50.
070.
005
0.25
0.01
0.19
0.01
0.65
70.
002
0.82
70.
009
0.71
0.01
4.79
10.
009
1.52
0.01
Poj
man
ski(1
997)
VZ
Aql
0.59
3633
762
0.22
6481
4072
0.6
0.09
0.42
0.05
0.20
0.06
0.65
0.12
0.30
0.09
0.09
0.04
0.91
0.07
0.31
0.16
6.15
0.07
3.40
0.16
INT
EG
RA
LV
1437
Sgr
0.57
2075
542
0.24
2546
6193
0.41
0.01
0.16
0.01
0.09
0.01
0.38
0.03
0.21
0.03
0.98
30.
005
0.41
0.01
0.69
0.02
4.33
0.02
1.51
0.03
Sosz
ynsk
iet
al.
(201
1b)
V71
4C
yg0.
5297
8296
40.
2759
0201
120.
420.
010.
150.
010.
110.
010.
360.
030.
270.
030.
383
0.00
40.
180.
010.
940.
024.
190.
011.
830.
02Sc
hmid
tet
al.
(200
5)V
439
Oph
0.52
8262
860.
2771
4992
170.
300.
020.
050.
020.
040.
020.
160.
070.
150.
080.
470.
060.
380.
150.
840.
344.
340.
165.
780.
35Sc
hmid
tet
al.
(200
5)RT
TrA
0.51
3842
147
0.28
9170
2764
0.32
30.
001
0.03
40.
001
0.03
10.
001
0.10
50.
004
0.09
50.
004
0.99
260.
0006
0.50
30.
006
0.69
30.
006
4.82
10.
005
1.35
00.
007
Poj
man
ski(1
997)
GK
Cen
0.51
2882
982
0.28
9981
711
0.26
70.
007
0.04
90.
006
0.03
10.
007
0.18
0.02
0.12
0.02
0.79
60.
004
0.09
0.02
0.23
0.03
4.72
0.02
2.18
90.
04Poj
man
ski(1
997)
AT
Tel
0.50
7627
684
0.29
4454
7012
0.28
50.
030.
120.
020.
060.
020.
430.
090.
190.
070.
340.
010.
940.
030.
500.
243.
190.
046.
130.
24Poj
man
ski(1
997)
V47
7O
ph0.
4960
8627
40.
3044
4278
910.
340.
020.
120.
040.
060.
020.
370.
130.
190.
060.
930.
010.
330.
200.
230.
104.
500.
205.
840.
10Poj
man
ski(1
997)
V12
87Sc
o0.
4912
6587
10.
3086
8340
590.
220.
060.
140.
050.
080.
030.
630.
270.
390.
160.
510.
130.
970.
120.
040.
071.
210.
180.
010.
15Poj
man
ski(1
997)
V55
3C
en0.
4853
0573
90.
3139
8457
290.
230
0.00
20.
012
0.00
30.
020
0.00
30.
050.
010.
090.
010.
284
0.00
20.
005
0.17
70.
570.
064.
310.
171.
370.
06Poj
man
ski(1
997)
V56
08Sg
r0.
4519
3215
0.34
4926
7623
0.38
0.01
0.06
60.
009
0.03
760.
009
0.17
0.03
0.10
0.03
0.84
20.
004
0.22
0.03
0.20
0.05
4.93
0.03
4.23
0.05
Sosz
ynsk
iet
al.
(201
1b)
UY
Eri
0.45
1814
735
0.34
5039
6096
0.26
90.
002
0.11
10.
002
0.03
80.
002
0.41
50.
009
0.14
30.
007
0.95
20.
001
0.36
90.
003
0.78
90.
009
4.49
40.
004
2.72
30.
009
Poj
man
ski(1
997)
UX
Nor
0.41
9109
544
0.37
7672
4493
0.38
0.02
0.21
0.02
0.13
0.02
0.56
0.07
0.35
0.06
0.62
0.01
0.69
0.02
0.86
0.03
4.45
0.02
3.25
0.03
Poj
man
ski(1
997)
V61
7A
ra0.
3965
1221
40.
4017
4343
030.
231
0.00
30.
061
0.00
30.
028
0.00
30.
270.
010.
120.
010.
996
0.00
20.
446
0.00
70.
910.
014.
426
0.00
72.
650.
01Poj
man
ski(1
997)
V35
1C
ep0.
3563
0334
90.
4481
8009
560.
149
0.00
70.
022
0.00
70.
011
0.00
60.
150.
050.
080.
040.
959
0.00
80.
120.
050.
080.
122.
850.
054.
420.
12Sz
abad
os(1
977)
,H
ende
n(1
980)
V46
5O
ph0.
3516
5193
60.
4538
8698
730.
400.
010.
140.
010.
070.
010.
340.
030.
170.
030.
673
0.00
40.
830.
010.
970.
034.
650.
012.
830.
03Poj
man
ski(1
997)
DQ
And
0.31
2444
362
0.50
5227
3077
0.31
60.
005
0.13
30.
005
0.07
80.
006
0.42
0.02
0.25
0.02
0.50
50.
003
0.43
30.
007
0.37
0.01
4.22
80.
007
2.22
0.02
Schm
idt
etal
.(2
005)
BE
CrA
0.29
9683
177
0.52
3337
6359
0.47
0.03
0.18
0.06
0.10
0.03
0.38
0.14
0.21
0.06
0.58
40.
006
0.67
0.21
0.85
0.09
4.76
0.21
3.73
0.09
Poj
man
ski(1
997)
FM
Del
0.29
9679
663
0.52
3342
7283
0.47
0.03
0.18
0.06
0.10
0.03
0.37
0.14
0.21
0.06
0.59
70.
006
0.65
0.20
0.79
0.08
4.45
0.20
3.16
0.08
Poj
man
ski(1
997)
BD
Cas
0.27
3901
489
0.56
2405
6068
0.16
00.
002
0.01
60.
002
0.00
70.
002
0.10
0.01
0.05
0.01
0.08
00.
002
0.54
0.03
0.74
0.06
3.98
0.03
0.02
0.06
INT
EG
RA
LV
5609
Sgr
0.28
2290
865
0.54
9303
1755
0.30
20.
010
0.11
20.
010
0.05
60.
009
0.37
0.03
0.19
0.03
0.71
40.
005
0.01
0.01
0.27
0.03
5.25
0.01
3.96
0.03
Sosz
ynsk
iet
al.
(201
1b)
QY
Cyg
0.25
6861
546
0.59
0300
9078
0.19
0.03
0.14
0.03
0.15
0.03
0.70
0.20
0.78
0.20
0.30
0.02
0.88
0.03
0.74
0.03
3.40
0.04
2.22
0.04
INT
EG
RA
LV
383
Cyg
0.21
6813
043
0.66
3914
5951
0.24
80.
006
0.07
60.
006
0.03
90.
007
0.31
0.03
0.16
0.03
0.64
60.
004
0.71
0.01
0.81
0.03
4.21
0.01
2.33
0.03
Ber
dnik
ov(2
008)
,A
AV
SOV
675
Cen
0.21
6011
549
0.66
5523
0288
0.29
80.
009
0.11
40.
006
0.05
0.02
0.38
0.02
0.17
0.07
0.31
70.
003
0.57
0.01
0.18
0.22
1.15
0.01
4.60
0.22
Poj
man
ski(1
997)
V39
4C
ep0.
1758
0782
60.
7549
6179
640.
371
0.00
60.
150.
030.
060
0.00
80.
390.
070.
160.
020.
065
0.00
40.
590.
190.
070.
024.
450.
192.
330.
02IN
TE
GR
AL
AB
Ara
0.16
7854
242
0.77
5067
6788
0.34
0.01
0.13
0.01
0.04
0.01
0.39
0.03
0.13
0.03
0.63
90.
005
0.79
0.01
0.97
0.06
4.82
0.01
3.46
0.06
Poj
man
ski(1
997)
TX
Del
0.16
2177
362
0.79
0009
7682
0.29
40.
002
0.07
20.
002
0.02
20.
002
0.24
50.
009
0.07
60.
008
0.77
60.
001
0.09
10.
006
0.36
0.02
4.96
00.
006
3.32
0.19
Poj
man
ski(1
997)
UY
CrA
0.14
2949
436
0.84
4817
5538
0.52
0.02
0.13
0.02
0.14
0.02
0.25
0.05
0.27
0.04
0.01
90.
007
0.43
0.03
0.05
0.03
4.00
0.03
3.10
0.03
3IN
TE
GR
AL
ITC
ep0.
1360
8104
70.
8662
0235
790.
232
0.00
50.
077
0.00
40.
016
0.00
40.
330.
020.
070.
020.
587
0.00
30.
700.
010.
730.
054.
870.
012.
960.
05Sc
hmid
tet
al.
(200
5)
30
ACs DISCOVERED IN A SAMPLE OF GALACTIC SHORT PERIOD TIICsTab
leA
.2.
The
Four
ier
para
met
ers
ofth
eA
Cs
inth
eLM
Cus
ing
the
V-b
and
data
from
the
OG
LE
-III
surv
ey.
OG
LE
-LM
C-
AC
EP
f 0lo
gP
[day
s]A
1A
1err
A2
A2err
A3
A3err
R21
R21err
R31
R31err
φ1
φ1err
φ2
φ2err
φ3
φ3err
φ21
φ21err
φ31
φ31err
32.
6193
0268
−0.4
1818
5687
30.
379
0.01
50.
128
0.03
10.
052
0.01
80.
338
0.08
20.
136
0.04
60.
705
0.00
50.
704
0.15
10.
967
0.23
23.
417
0.15
12.
214
0.23
26
1.17
7078
09−0
.070
8052
759
0.25
60.
011
0.12
0.00
90.
053
0.01
70.
469
0.03
80.
204
0.06
50.
564
0.00
40.
647
0.01
10.
782
0.28
74.
834
0.01
13.
713
0.28
77
1.11
5553
71−0
.047
4904
849
0.44
0.03
0.16
50.
026
0.09
90.
033
0.37
60.
063
0.22
40.
076
0.18
30.
008
0.72
10.
027
0.46
20.
253
3.80
30.
028
2.60
20.
253
81.
3349
7031
−0.1
2547
1607
0.2
0.00
70.
062
0.00
60.
021
0.00
40.
307
0.02
80.
103
0.02
10.
040.
005
0.29
0.06
40.
887
0.05
2.88
80.
064
1.67
80.
0514
0.43
6427
013
0.36
0088
3762
0.34
80.
010.
149
0.03
80.
063
0.01
0.42
60.
109
0.18
0.02
90.
916
0.01
10.
328
0.23
20.
751
0.02
74.
691
0.23
23.
167
0.02
916
0.64
6943
545
0.18
9133
616
0.42
10.
009
0.21
10.
013
0.14
30.
009
0.50
10.
033
0.33
90.
023
0.08
20.
003
0.42
30.
010.
821
0.01
3.2
0.01
0.47
50.
011
171.
0752
7992
−0.0
3152
1535
80.
335
0.01
50.
135
0.01
70.
089
0.01
50.
403
0.05
20.
264
0.04
40.
492
0.00
70.
353
0.08
40.
411
0.02
63.
883
0.08
52.
729
0.02
719
1.09
9620
29−0
.041
2427
448
0.44
90.
007
0.19
20.
007
0.12
50.
006
0.42
70.
016
0.27
90.
014
0.42
10.
002
0.18
40.
005
0.97
30.
008
3.72
30.
006
1.33
30.
009
202.
6184
651
−0.4
1804
6789
80.
345
0.00
90.
126
0.03
90.
047
0.00
80.
366
0.11
40.
135
0.02
30.
687
0.00
40.
626
0.22
40.
565
0.08
3.15
50.
224
0.03
10.
0821
0.77
1695
927
0.11
2553
7919
0.38
10.
004
0.18
10.
004
0.15
0.00
30.
474
0.01
10.
393
0.00
90.
671
0.00
20.
727
0.00
50.
807
0.00
33.
992
0.00
51.
859
0.00
422
1.56
0188
52−0
.193
1770
780.
296
0.01
80.
132
0.01
70.
095
0.01
10.
446
0.06
10.
322
0.04
10.
192
0.00
80.
664
0.01
70.
486
0.06
43.
330.
019
2.57
70.
065
231.
3822
9242
−0.1
4059
9926
50.
250.
003
0.12
20.
004
0.05
70.
003
0.48
60.
014
0.22
60.
012
0.74
40.
002
0.91
10.
004
0.98
70.
009
4.22
90.
004
1.61
40.
009
241.
2587
1428
−0.0
9992
7159
30.
288
0.01
30.
130.
011
0.09
20.
012
0.45
0.04
20.
319
0.04
30.
867
0.00
70.
011
0.01
50.
351
0.02
23.
314
0.01
61.
580.
022
260.
5751
2663
40.
2402
3651
980.
339
0.00
50.
167
0.00
50.
108
0.00
50.
492
0.01
50.
319
0.01
50.
666
0.00
20.
775
0.00
50.
858
0.00
74.
354
0.00
62.
264
0.00
732
0.75
9864
208
0.11
9264
0116
0.24
80.
005
0.11
20.
027
0.06
90.
005
0.45
10.
110.
278
0.02
0.54
90.
005
0.47
90.
150.
472
0.01
63.
970.
152.
050.
016
352.
2419
1287
−0.3
5061
8730
10.
339
0.00
70.
128
0.03
40.
038
0.00
70.
376
0.09
90.
112
0.01
90.
055
0.00
40.
511
0.21
90.
008
0.08
24.
090.
219
2.15
70.
083
360.
7949
2971
70.
0996
7126
740.
178
0.01
30.
061
0.01
20.
031
0.01
40.
341
0.07
0.17
30.
075
0.43
80.
007
0.27
10.
023
0.14
60.
047
4.05
80.
024
2.09
20.
047
380.
7489
4953
20.
1255
4744
630.
285
0.01
30.
134
0.03
90.
094
0.01
40.
469
0.13
80.
329
0.05
20.
862
0.01
0.13
80.
250.
376
0.08
54.
173
0.25
1.82
70.
086
391.
0076
5091
−0.0
0331
0101
40.
331
0.01
10.
143
0.03
40.
108
0.01
50.
430.
102
0.32
50.
044
0.89
80.
007
0.22
10.
229
0.54
0.02
54.
248
0.22
92.
189
0.02
640
1.04
1040
59−0
.017
4676
629
0.3
0.00
80.
117
0.00
80.
084
0.00
70.
389
0.02
70.
278
0.02
50.
206
0.00
40.
80.
010.
421
0.01
54.
012
0.01
11.
913
0.01
541
1.13
8769
29−0
.056
4357
467
0.30
80.
007
0.12
10.
008
0.08
30.
019
0.39
20.
025
0.26
90.
062
0.15
90.
004
0.70
50.
008
0.24
30.
276
4.00
90.
009
1.68
0.27
644
0.76
4227
056
0.11
6777
591
0.45
0.00
50.
237
0.00
50.
160.
005
0.52
70.
012
0.35
60.
011
0.81
40.
002
0.05
50.
003
0.29
30.
005
4.24
90.
004
2.20
90.
005
460.
7913
1711
10.
1016
4944
320.
328
0.00
40.
097
0.00
40.
095
0.00
40.
296
0.01
20.
289
0.01
10.
054
0.00
20.
284
0.00
40.
045
0.00
62.
676
0.00
42.
405
0.00
648
0.64
6873
474
0.18
9180
6574
0.39
80.
004
0.21
0.00
40.
136
0.00
40.
528
0.01
0.34
0.00
90.
630.
002
0.68
10.
003
0.74
0.00
44.
223
0.00
32.
211
0.00
449
1.55
0870
39−0
.190
5755
043
0.22
60.
010.
108
0.00
90.
080.
010.
477
0.04
50.
354
0.04
50.
399
0.00
70.
20.
015
0.93
50.
021
4.10
30.
017
1.50
40.
022
511.
4112
5232
−0.1
4960
4668
90.
226
0.00
80.
055
0.00
80.
051
0.01
10.
242
0.03
60.
224
0.04
90.
068
0.00
70.
289
0.04
10.
051
0.10
92.
540.
042
2.19
30.
109
520.
7920
3836
50.
1012
5378
140.
413
0.02
90.
202
0.02
40.
171
0.04
70.
488
0.06
70.
413
0.11
70.
232
0.01
0.79
10.
029
0.47
90.
192
3.62
10.
031.
780.
193
530.
5296
2897
50.
2760
2826
350.
437
0.01
0.20
50.
008
0.10
80.
006
0.46
80.
020.
247
0.01
50.
104
0.00
50.
670.
011
0.14
90.
024.
475
0.01
22.
124
0.02
570.
5847
8933
20.
2330
0055
860.
403
0.00
40.
236
0.00
40.
171
0.00
30.
585
0.01
0.42
40.
007
0.15
60.
001
0.81
50.
002
0.45
70.
003
4.72
60.
002
3.07
20.
003
600.
7838
6268
40.
1057
6000
980.
475
0.00
60.
245
0.00
60.
159
0.00
60.
516
0.01
30.
335
0.01
20.
201
0.00
20.
819
0.00
40.
441
0.00
64.
188
0.00
42.
125
0.00
662
0.94
4212
450.
0249
3027
740.
485
0.00
80.
208
0.00
70.
129
0.00
80.
429
0.01
60.
266
0.01
70.
414
0.00
20.
214
0.00
70.
016
0.00
93.
996
0.00
71.
727
0.00
963
1.11
9782
42−0
.049
1336
450.
331
0.01
60.
115
0.01
40.
055
0.01
0.34
80.
044
0.16
60.
030.
208
0.00
50.
811
0.01
60.
716
0.03
64.
051
0.01
73.
717
0.03
665
0.75
6691
193
0.12
1081
3207
0.46
80.
006
0.23
40.
006
0.14
50.
006
0.50
10.
014
0.30
90.
012
0.42
50.
002
0.28
30.
004
0.13
70.
006
4.29
40.
005
2.28
40.
006
31
M. I. JURKOVICTab
leA
.3.
The
Four
ier
para
met
ers
ofth
eB
LH
sin
the
LM
Cus
ing
the
V-b
and
data
from
the
OG
LE
-III
surv
ey.
OG
LE
-LM
C-
T2C
EP
f 0lo
gP
[day
s]A
1A
1err
A2
A2err
A3
A3err
R21
R21err
R31
R31err
φ1
φ1err
φ2
φ2err
φ3
φ3err
φ21
φ21err
φ31
φ31err
70.
8047
2129
10.
0943
5450
810.
363
0.00
80.
098
0.01
0.04
50.
007
0.27
0.02
80.
123
0.01
80.
246
0.00
30.
889
0.01
20.
871
0.03
54.
070.
013
3.98
40.
035
90.
5677
3494
40.
2458
5437
420.
413
0.01
0.16
90.
011
0.08
70.
011
0.40
80.
028
0.20
90.
025
0.73
80.
005
0.88
40.
011
0.88
60.
018
4.14
20.
012
1.09
80.
019
240.
8021
2731
0.09
5756
697
0.37
0.01
40.
096
0.01
30.
033
0.01
40.
258
0.03
60.
089
0.03
80.
023
0.00
60.
448
0.02
70.
207
0.27
54.
099
0.02
84.
022
0.27
530
0.25
4110
433
0.59
4977
5038
0.25
60.
016
0.08
20.
028
0.04
0.01
60.
321
0.11
0.15
50.
062
0.26
90.
007
0.14
20.
395
0.97
0.22
65.
372
0.39
54.
174
0.22
648
0.69
1842
499
0.15
9992
7633
0.42
60.
026
0.14
70.
046
0.06
40.
033
0.34
50.
110.
150.
076
0.96
80.
003
0.31
80.
293
0.42
20.
378
3.96
80.
293
0.11
40.
378
490.
3090
9373
60.
5099
0979
610.
176
0.00
90.
048
0.01
20.
011
0.00
70.
272
0.06
50.
061
0.03
70.
931
0.00
80.
392
0.07
60.
891
0.29
4.90
60.
076
3.76
60.
2953
0.95
8773
630.
0182
8391
930.
447
0.01
50.
203
0.01
0.08
80.
027
0.45
40.
027
0.19
60.
060.
793
0.00
90.
076
0.01
80.
345
0.18
74.
649
0.02
2.93
60.
187
600.
8086
8095
90.
0922
2278
260.
433
0.00
80.
106
0.01
20.
025
0.00
70.
244
0.02
70.
057
0.01
70.
585
0.00
50.
570.
011
0.86
50.
345
4.08
0.01
23.
834
0.34
561
0.84
6373
695
0.07
2437
8428
0.31
60.
005
0.06
30.
006
0.02
70.
005
0.19
90.
017
0.08
30.
015
0.71
50.
003
0.88
0.01
30.
138
0.02
44.
403
0.01
33.
112
0.02
568
0.62
1385
688
0.20
6638
7538
0.21
80.
005
0.05
30.
005
0.02
40.
005
0.24
30.
022
0.11
10.
020.
029
0.00
40.
508
0.01
50.
582
0.03
24.
398
0.01
66.
255
0.03
369
0.97
9185
356
0.00
9135
0901
0.17
90.
017
0.05
10.
013
0.04
50.
016
0.28
20.
074
0.24
90.
091
0.01
50.
011
0.59
0.1
0.17
20.
285.
089
0.10
13.
947
0.28
171
0.86
7929
397
0.06
1515
6017
0.43
10.
006
0.13
90.
006
0.02
70.
007
0.32
20.
013
0.06
10.
015
0.65
90.
002
0.77
0.00
70.
829
0.11
14.
412
0.00
72.
217
0.11
173
0.32
3840
472
0.48
9668
8762
0.38
40.
019
0.13
10.
014
0.06
70.
013
0.34
0.03
90.
175
0.03
50.
488
0.00
50.
535
0.16
10.
558
0.02
5.07
70.
162
3.72
80.
0276
0.47
5216
778
0.32
3108
2346
0.42
70.
020.
138
0.02
30.
085
0.02
90.
321
0.05
50.
199
0.06
80.
771
0.00
90.
059
0.06
10.
197
0.19
74.
823
0.06
22.
421
0.19
777
0.82
3863
080.
0841
4495
890.
151
0.00
50.
039
0.00
50.
011
0.00
40.
255
0.03
20.
070.
027
0.18
30.
005
0.86
30.
049
0.44
60.
263
4.69
20.
049
2.49
70.
263
850.
2936
7742
50.
5321
2943
640.
298
0.00
60.
090.
006
0.03
30.
005
0.30
10.
021
0.11
0.01
60.
257
0.00
30.
097
0.00
80.
913
0.03
15.
244
0.00
84.
046
0.03
289
0.85
6677
040.
0671
8287
260.
373
0.02
0.07
70.
022
0.02
90.
009
0.20
70.
060.
077
0.02
40.
327
0.05
80.
051
0.24
0.91
0.05
94.
075
0.24
72.
711
0.08
290
0.67
6157
034
0.16
9952
4297
0.22
40.
006
0.03
80.
007
0.03
30.
007
0.16
80.
029
0.14
40.
028
0.74
60.
004
0.03
0.08
0.75
0.05
24.
948
0.08
10.
072
0.05
292
0.38
2183
436
0.41
7728
1394
0.34
70.
020.
088
0.02
90.
039
0.01
40.
253
0.08
40.
112
0.04
0.44
0.00
60.
425
0.25
20.
372
0.24
84.
989
0.25
23.
467
0.24
810
20.
7898
7554
20.
1024
4133
360.
436
0.00
60.
123
0.00
50.
044
0.00
50.
283
0.01
20.
101
0.01
10.
214
0.00
20.
858
0.00
70.
545
0.01
94.
275
0.00
72.
541
0.02
105
0.67
1455
760.
1729
8259
630.
408
0.00
50.
140.
006
0.05
50.
006
0.34
30.
013
0.13
50.
014
0.88
90.
002
0.15
70.
006
0.19
30.
035
3.95
10.
006
0.16
30.
035
107
0.82
7030
392
0.08
2478
5305
0.23
90.
008
0.05
40.
015
0.02
20.
008
0.22
50.
062
0.09
10.
031
0.99
70.
005
0.39
20.
395
0.88
10.
122
4.07
30.
395
2.45
50.
123
116
0.50
8472
942
0.29
3732
1528
0.28
40.
006
0.03
80.
006
0.03
60.
007
0.13
40.
021
0.12
50.
023
0.20
50.
004
0.92
20.
024
0.46
80.
028
4.78
60.
024
2.21
90.
028
138
0.71
7571
438
0.14
4134
8561
0.31
20.
007
0.06
0.00
90.
028
0.00
90.
190.
029
0.08
90.
026
0.36
10.
004
0.14
60.
067
0.48
90.
051
4.23
70.
067
5.69
80.
051
145
0.29
9622
540.
5234
2551
860.
130.
004
0.02
40.
004
0.00
60.
004
0.17
90.
030.
041
0.02
50.
365
0.00
40.
214
0.07
30.
098
0.15
74.
611
0.07
33.
162
0.15
714
80.
3742
8936
80.
4267
9250
920.
343
0.00
60.
097
0.02
60.
054
0.00
70.
283
0.07
50.
157
0.02
10.
872
0.00
40.
306
0.21
80.
692
0.03
95.
103
0.21
83.
621
0.03
916
00.
5692
5435
40.
2446
9363
90.
338
0.01
20.
094
0.01
20.
071
0.01
70.
277
0.03
50.
210.
050.
796
0.00
40.
012
0.01
30.
063
0.17
24.
208
0.01
41.
102
0.17
216
30.
5904
5229
40.
2288
1518
580.
238
0.01
0.03
60.
010.
050.
013
0.14
90.
041
0.20
70.
054
0.19
20.
008
0.84
40.
166
0.3
0.12
34.
466
0.16
61.
416
0.12
317
10.
6431
8573
20.
1916
6359
820.
171
0.00
60.
025
0.00
60.
042
0.00
70.
146
0.03
60.
245
0.04
10.
239
0.00
70.
664
0.05
10.
277
0.02
92.
740.
051
0.37
80.
03
32
ACs DISCOVERED IN A SAMPLE OF GALACTIC SHORT PERIOD TIICs
ANOMALNE CEFEIDE OTKRIVENE U UZORKU GALAKTIQKIHKRATKOPERIODIQNIH CEFEIDA TIPA II
M. I. Jurkovic1,2
1Astronomical Observatory, Volgina 7, 11060 Belgrade, Serbia2Konkoly Thege Miklos Astronomical Institute, Research Centre forAstronomy and Earth Sciences, Hungarian Academy of Sciences
H-1121 Budapest, Konkoly Thege Miklos ut 15-17, HungaryE–mail: [email protected]
UDK 524.333.7 : 524.6Originalni nauqni rad
Ponovo smo razmotrili kratkoperi-odiqne cefeide tipa II, poznate kao zvezdetipa BL Herculis (BLH), u Galaktiqkom polju dabismo izveli homogenu analizu njihovih Fu-rijeovih parametara.
Koristili smo iskljuqivo podatke sa-kupljene u V filtru da bismo obezbedili da sepromenljive iz kataloga OGLE-III mogu direk-tno uporediti sa 59 zvezda, koje su bile klasi-fikovane kao kratkoperiodiqne cefeide tipaII u Opxtem katalogu promenljivih zvezda, unaxem uzorku.
Od 59 zvezda naxli smo da je 19 BLHtipa, 19 su anomalne cefeide (AC) koje pul-siraju u fundamentalnoj modi (8 od ovihje ve� prethodno bilo klasifikovano odstrane Pregleda neba Katalina, 1 je ano-malna cefeida koja pulsira na drugom har-moniku, za 2 pretpostavljamo da su specifiqnezvezde tipa W Virginis, 11 su klasiqne ce-
feide (δ Cep), a 7 uopxte nisu pulsiraju�ezvezde. Kreirali smo listu sjajnih BLH zvezdau Galaksiji i razdvojili smo AC, kao i drugeobjekte, koji su bili pogrexno klasifiko-vani. Broj stvarnih zvezda tipa BLH u naxemuzorku se smanjio za vixe od 50%. Sakupilismo metaliqnosti dobijene iz spektroskop-skih merenja koja su bila objavljena u lite-raturi. Iako je broj stvarnih merenja mali,veoma je verovatno da su AC niske meta-liqnosti. Proseqna metaliqnost iz 8 merenja4 zvezde (UY Eri ima 5 razliqitih merenja[Fe/H]) je −1.12 dex, ali ako izostavimo vred-nosti metaliqnosti koje se drastiqno raz-likuju kod zvezde UY Eri onda proseqna me-taliqnost postaje −1.88 dex, bez obzira nato da li se AC nalazi unutar samog Mleq-nog puta ili u nekom od obli�njih jata. Sadruge strane, qini se da zvezde BLH imajumetaliqnost sliqnu Suncu, 0.00 dex, koja jeraqunata iz 21 merenja ra�enih za 10 zvezda.
33