hi column densities, kinematics, and metallicities in strong mgii absorbers
DESCRIPTION
HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers. Dave Turnshek University of Pittsburgh. Outline: Strong MgII Absorbers (low ionization, neutral gas) HI Column Densities (DLAs and sub-DLAs) Kinematics Element Abundances Model Implications - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/1.jpg)
HI Column Densities, Kinematics, and Metallicities in Strong MgII
Absorbers
Dave TurnshekUniversity of Pittsburgh
![Page 2: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/2.jpg)
Outline:Outline: Strong MgII Absorbers (low ionization, neutral gas)Strong MgII Absorbers (low ionization, neutral gas)
HI Column Densities (DLAs and sub-DLAs)HI Column Densities (DLAs and sub-DLAs) KinematicsKinematics Element AbundancesElement Abundances
Model ImplicationsModel Implications DLA Absorbing Galaxies DLA Absorbing Galaxies
Selection Effects (esp. MgII)Selection Effects (esp. MgII)
Pittsburgh Collaborators:Pittsburgh Collaborators: Sandhya RaoSandhya Rao Michele Belfort-MihalyiMichele Belfort-Mihalyi Daniel Nestor (now U. Florida)Daniel Nestor (now U. Florida) Anna Quider Anna Quider + SDSS collaborators …+ SDSS collaborators …
![Page 3: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/3.jpg)
Strong MgII AbsorbersStrong MgII Absorbers(MgII(MgII2796 REW > 0.3 Å)2796 REW > 0.3 Å)
Detected in large numbers at 0.4 < z < 2.2 Detected in large numbers at 0.4 < z < 2.2 by SDSS (e.g., Nestor, Turnshek, Rao 2005)by SDSS (e.g., Nestor, Turnshek, Rao 2005)
Selection biased by gas cross sectionSelection biased by gas cross section
Tracers for DLAs when REW2796 > 0.6 Å Tracers for DLAs when REW2796 > 0.6 Å (Rao, Turnshek, Nestor 2005)(Rao, Turnshek, Nestor 2005)
Remainder are mostly sub-DLAs Remainder are mostly sub-DLAs (incomplete?)(incomplete?)
![Page 4: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/4.jpg)
MgIIMgII2796 REW 2796 REW DistributionDistribution
Left: Left: MMT + MMT + SDSSSDSS
Right: Right: SDSS SDSS alonealone
![Page 5: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/5.jpg)
Incidence of MgII REWs: z = 0.4 Incidence of MgII REWs: z = 0.4 2.22.2
Dashed: no Dashed: no evolution evolution curve (NEC)curve (NEC)
Larger Larger REWs REWs decrease decrease relative to relative to NEC at NEC at decreasing decreasing redshiftredshift
![Page 6: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/6.jpg)
HI Column DensitiesHI Column Densities
Rao, Turnshek, Nestor (2005):Rao, Turnshek, Nestor (2005): HST UV spectra of 197 strong MgII absorbers HST UV spectra of 197 strong MgII absorbers
MgIIMgII2796 REW > 0.6 Å:2796 REW > 0.6 Å: DLA fraction increases with increasing REWDLA fraction increases with increasing REW Mean N(HI) = 4(10Mean N(HI) = 4(102020) atoms/cm) atoms/cm2
0.3 Å < MgII0.3 Å < MgII2796 REW < 0.6 Å:2796 REW < 0.6 Å: Mean N(HI) = 10Mean N(HI) = 101919 atoms/cm atoms/cm2
![Page 7: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/7.jpg)
Mean HI Column DensitiesMean HI Column Densities(all strong MgII absorbers)(all strong MgII absorbers)
![Page 8: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/8.jpg)
Mean HI Column DensitiesMean HI Column Densities
all strong MgIIs: only MgII DLAs:
![Page 9: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/9.jpg)
Strong MgII Absorber Strong MgII Absorber KinematicsKinematics
Doublet ratios indicate that strong MgIIs are saturated. Their REWs are mainly indicators of absorptionvelocity spread.
e.g., Petitjean (1998)
![Page 10: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/10.jpg)
DLA Fraction and Mean HI DLA Fraction and Mean HI Column Density vs. REW in Column Density vs. REW in
Velocity UnitsVelocity Units(all strong MgII absorbers)(all strong MgII absorbers)
REW is given inunits of km/s instead of Åon the top horizontal axis.
![Page 11: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/11.jpg)
Element Abundances Element Abundances in Strong MgII Absorbersin Strong MgII Absorbers
Use SDSS composite spectra (high S/N)Use SDSS composite spectra (high S/N)
MgII2796 REW measures kinematicsMgII2796 REW measures kinematics
Metallicities from weak unsaturated linesMetallicities from weak unsaturated lines
Study metallicity - kinematics correlationsStudy metallicity - kinematics correlations
![Page 12: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/12.jpg)
Metallicity–Kinematics Metallicity–Kinematics CorrelationCorrelation
(ZnII, CrII, MgII SDSS (ZnII, CrII, MgII SDSS Composites)Composites)
Approximately6000 strongMgII absorbers.
Also seen inSiII, FeII, and MnII.
![Page 13: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/13.jpg)
Metallicity–Kinematics Metallicity–Kinematics CorrelationCorrelation
(ZnII and CrII SDSS Composites)(ZnII and CrII SDSS Composites)
Approximately6000 strongMgII absorbers.
MgII2796 REWintervals notedin units of km/s.
ZnII CrII
![Page 14: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/14.jpg)
DLA Fraction and Mean HI DLA Fraction and Mean HI Column Density versus Column Density versus
Velocity SpreadVelocity Spread(all strong MgII absorbers)(all strong MgII absorbers)
REW is given inunits of km/s instead of Åon the top horizontal axis.
![Page 15: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/15.jpg)
Metallicity–Kinematics Metallicity–Kinematics CorrelationCorrelation
(Zn, Cr, Si, Mn, and Fe)(Zn, Cr, Si, Mn, and Fe)
rare largeREW systems
![Page 16: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/16.jpg)
Metallicity–Kinematics Metallicity–Kinematics CorrelationCorrelation(Zn and Cr)(Zn and Cr)
(more depletion)
(little depletion)
![Page 17: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/17.jpg)
Metallicity–Kinematics Metallicity–Kinematics CorrelationCorrelation(Zn and Si)(Zn and Si)
(-enhancement)
![Page 18: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/18.jpg)
Metallicity–Kinematics Metallicity–Kinematics CorrelationCorrelation
(Keck HIRES data, z=1.74.2, taken from Prochaska et al.)
![Page 19: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/19.jpg)
Model Implications Model Implications (z=0.5(z=0.52)2)
Kinematic spread at z=1Kinematic spread at z=12 consistent with 2 consistent with predictions of Mo, Mao, White (1998) predictions of Mo, Mao, White (1998)
DLA galaxy impact parameters at z<1 DLA galaxy impact parameters at z<1 consistent with Mo, Mao, White (1998) consistent with Mo, Mao, White (1998) predictions at z=1predictions at z=1
Implications for cosmic SFRImplications for cosmic SFR DLAs different from LBGs (Mo, Mao, White 1998)DLAs different from LBGs (Mo, Mao, White 1998) Application of Kennicutt’s Schmidt Law to DLAs Application of Kennicutt’s Schmidt Law to DLAs
suggests DLAs contribute at low-z, not at high-z suggests DLAs contribute at low-z, not at high-z (Hopkins, Rao, Turnshek 2005; Rao talk)(Hopkins, Rao, Turnshek 2005; Rao talk)
![Page 20: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/20.jpg)
DLA Fraction and Mean HI DLA Fraction and Mean HI Column Density versus Column Density versus
Velocity SpreadVelocity Spread(all strong MgII absorbers)(all strong MgII absorbers)
REW is given inunits of km/s instead of Åon the top horizontal axis.
![Page 21: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/21.jpg)
Kinematics and Impact Kinematics and Impact ParameterParameter
(Mo, Mao, White 1998)(Mo, Mao, White 1998)
![Page 22: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/22.jpg)
DLA Galaxy Properties (z<1)DLA Galaxy Properties (z<1)(updated from Rao et al. 2003)(updated from Rao et al. 2003)
![Page 23: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/23.jpg)
Selection EffectsSelection Effects The probability of detecting a DLA absorber is The probability of detecting a DLA absorber is
the product of their comoving number the product of their comoving number density times their gas cross section.density times their gas cross section.
Could we be missing very high N(HI) Could we be missing very high N(HI) absorbers with low neutral gas cross section?absorbers with low neutral gas cross section? Detection of one low cross section system with Detection of one low cross section system with
N(HI) = 10N(HI) = 102323 atoms/cm atoms/cm2 would require doubling would require doubling ΩΩHI
MgII REW selection biasMgII REW selection bias Not relevant Not relevant ΩΩHI [since mean N(HI) flat with REW] [since mean N(HI) flat with REW] Relevant for cosmic metallicity and DLA galaxy IDsRelevant for cosmic metallicity and DLA galaxy IDs
![Page 24: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/24.jpg)
Ultra-StrongUltra-StrongMgII FieldsMgII Fields
Recent WIYN Recent WIYN observations of observations of Nestor et al.Nestor et al.
![Page 25: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/25.jpg)
Example of an Ultra-Strong Example of an Ultra-Strong MgIIMgII
FeII region MgII + MgI region
![Page 26: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/26.jpg)
DLA Galaxy Properties (z<1)DLA Galaxy Properties (z<1)(updated from Rao et al. 2003)(updated from Rao et al. 2003)
![Page 27: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/27.jpg)
Summary: Strong MgII Summary: Strong MgII AbsorbersAbsorbers
Galaxies Selected by Gas Cross-Section Galaxies Selected by Gas Cross-Section
HST UV: N(HI) – kinematics correlationHST UV: N(HI) – kinematics correlation
SDSS: kinematics – metallicity correlationSDSS: kinematics – metallicity correlation
Consistency with Mo, Mau, White (1998)?Consistency with Mo, Mau, White (1998)?
MgII selection effects need to be MgII selection effects need to be incorporatedincorporated
![Page 28: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/28.jpg)
Extras …Extras …
![Page 29: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/29.jpg)
DLA Galaxy Properties (z<1)DLA Galaxy Properties (z<1)(updated from Rao et al. 2003)(updated from Rao et al. 2003)
![Page 30: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/30.jpg)
PKS 1127-145 PKS 1127-145
IRTF K-IRTF K-band band imaging imaging of DLA of DLA field at field at z=0.313z=0.313..
![Page 31: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/31.jpg)
Strong MgII Nearest Strong MgII Nearest Neighbors Neighbors
IRTF K-IRTF K-band band imaging imaging of DLA of DLA and and sub-DLA sub-DLA fields at fields at z<1.z<1.
![Page 32: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/32.jpg)
Strong MgII Nearest Strong MgII Nearest Neighbors Neighbors
IRTF K-IRTF K-band band imaging imaging of DLA of DLA and and sub-DLA sub-DLA fields at fields at z<1.z<1.
![Page 33: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/33.jpg)
Schmidt LawSchmidt Law
from Kennicutt (1998)from Kennicutt (1998)
![Page 34: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/34.jpg)
DLAs and Cosmic Star DLAs and Cosmic Star FormationFormation
Hatched Hatched region: region: observed observed cosmic cosmic SFRSFR
Filled Filled circles: circles: DLAsDLAs
Hopkins, Rao, Turnshek (2005)
![Page 35: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/35.jpg)
DLAs and Cosmic Star DLAs and Cosmic Star FormationFormation
Hatched Hatched regions: regions: neutral gas neutral gas and and stellar stellar mass mass densities densities predicted predicted from from observed observed cosmic SFRcosmic SFR
Filled Filled circles: circles: DLAsDLAs
Hopkins, Rao, Turnshek (2005)
![Page 36: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/36.jpg)
DLAs and Cosmic Star DLAs and Cosmic Star FormationFormation
Hatched Hatched region: region: metals metals predicted predicted from from observed observed cosmic cosmic SFRSFR
Filled Filled circles: circles: metals metals from from DLAsDLAs
Hopkins, Rao, Turnshek (2005)
![Page 37: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/37.jpg)
DLA Fraction in Strong DLA Fraction in Strong MgIIsMgIIs
![Page 38: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/38.jpg)
Mean HI Column DensitiesMean HI Column Densities
all strong MgIIs: only MgII DLAs:
![Page 39: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/39.jpg)
Evolution of Incidence of Evolution of Incidence of DLAsDLAs
Lower curve: Lower curve: no-evolutionno-evolution
incidence is incidence is product of product of absorber cross-absorber cross-section times section times absorber absorber number densitynumber density
Rao, Turnshek, Nestor (2005)
![Page 40: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/40.jpg)
Evolution of HI Evolution of HI Cosmological Mass Density Cosmological Mass Density
from DLAsfrom DLAs
DLA neutral DLA neutral gas mass is gas mass is ≈ constant at ≈ constant at z=0.5z=0.54.5, 4.5, but is 2 times but is 2 times lower at z=0.lower at z=0.
Rao, Turnshek, Nestor (2005)
![Page 41: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/41.jpg)
SDSS Spectrum of MgII SDSS Spectrum of MgII AbsorptionAbsorption
z=0.741 MgII absorption system (REW2796 = 2.95Angstroms)z=0.741 MgII absorption system (REW2796 = 2.95Angstroms)
Right: Strong MgII doublet and weakerMgI line.
Left: Two Strong FeII lines and threeweaker MnII lines.
![Page 42: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/42.jpg)
H I 21 cm Maps of Some Nearby Galaxies:
VLA and WSRT maps courtesy John Hibbard, NRAO
![Page 43: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/43.jpg)
H I 21 cm Maps of Some Nearby Galaxies:
VLA and WSRT maps courtesy John Hibbard, NRAO
![Page 44: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/44.jpg)
H I 21 cm Maps of Some Nearby Galaxies:
VLA and WSRT maps courtesy John Hibbard, NRAO
![Page 45: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/45.jpg)
Identification of MgII Absorbing Identification of MgII Absorbing GalaxiesGalaxies
Hubble SpaceTelescope imageof a field withseveral quasar absorption linesystem galaxiesidentified. A galaxy at the DLA redshift (z=0.656) is not visible.
Courtesy Chuck Steidel
Quasar 3C336Sightline
![Page 46: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/46.jpg)
Identification of DLA Absorbing Identification of DLA Absorbing GalaxiesGalaxies
Infrared K-band image of the Q0738+313 sightline with DLAs at z = 0.091 and z = 0.221. IDs put the galaxies at 0.08 and 0.1L*, respectively.
Turnshek et al. 2001
![Page 47: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/47.jpg)
Optical Images of Stars in M51:Courtesy NOAO
Deep exposure Short exposure
![Page 48: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/48.jpg)
Evolution of Neutral Gas Metal Evolution of Neutral Gas Metal AbundanceAbundance
Beginning Beginning to measure to measure abundanceabundances at lower-s at lower-z, seeing z, seeing evidence evidence for for evolution.evolution.
Rao et al. 2004
![Page 49: HI Column Densities, Kinematics, and Metallicities in Strong MgII Absorbers](https://reader035.vdocument.in/reader035/viewer/2022062809/5681584e550346895dc5a70e/html5/thumbnails/49.jpg)
XXXXXX
xxxxxx