the vela and geminga pulsars in the mid-infrared · introduction the crab pulsar the axps vela and...
TRANSCRIPT
The Vela and Geminga pulsars in the mid-infrared
A. A. Danilenko1, D. A. Zyuzin1, Yu. A. Shibanov1,2
& S. V. Zharikov3
1Ioffe Institute, St. Petersburg, Russia
2St. Petersburg State Polytechnical Univ., St. Petersburg, Russia
3Observatorio Astronomico Nacional SPM, UNAM, Mexico
Outline
IntroductionThe Crab pulsarThe AXPsVela and Geminga
ResultsIdentification of the pulsars in mid-IRPhotometry
DiscussionThe dust discAn unresolved PWN structure
Conclusions
Outline
IntroductionThe Crab pulsarThe AXPsVela and Geminga
ResultsIdentification of the pulsars in mid-IRPhotometry
DiscussionThe dust discAn unresolved PWN structure
Conclusions
The Crab pulsar and the nearby knot
Near-IR images and Optical/IR SED of the Crab (Sandberg & Sollerman
(2009)). The pulsar and the knot are marked by the blue and red ticks
consecuently. The Crab mid-IR fluxes are compatible with the spectral
extrapolation from the optical range if we account for contribution from
the knot which is not spatialy resolved from the pulsar in the mid-IR.
Outline
IntroductionThe Crab pulsarThe AXPsVela and Geminga
ResultsIdentification of the pulsars in mid-IRPhotometry
DiscussionThe dust discAn unresolved PWN structure
Conclusions
The AXPs
4U 0142+61
Wang, Chakrabarty & Kaplan(2006)
1E 2259+586
Kaplan et al. (2009)
Outline
IntroductionThe Crab pulsarThe AXPsVela and Geminga
ResultsIdentification of the pulsars in mid-IRPhotometry
DiscussionThe dust discAn unresolved PWN structure
Conclusions
Vela and Geminga
Vela,
PSR B0833−45;age ∼ 104 yr;distance to, 287+19
−17 pc;associated with SNR G263.9−3.3;Crab-like PWN detected in X-raysonly and some PWN features inγ-rays;
Geminga,
PSR J0633+1746;age ∼ 105 yr;distance to, 250+120
−60 pc;not associated with any SNR;bow shock PWN detected inX-rays and γ-rays;
Outline
IntroductionThe Crab pulsarThe AXPsVela and Geminga
ResultsIdentification of the pulsars in mid-IRPhotometry
DiscussionThe dust discAn unresolved PWN structure
Conclusions
Identification of the Vela pulsar
21.5 21.0 20.5 8:35:20.0 19.5RA
psr
5.8 microns
26.0
28.0
30.0
32.0
34.0
36.0
38.0
-45:10:40.0
42.0
44.0
46.0
Dec
psr
J
21.5 21.0 20.5 8:35:20.0 19.5
24.0
26.0
28.0
-45:10:30.0
32.0
34.0
36.0
38.0
40.0
42.0
44.0
RA
Dec
psr
3.6 microns
psr
counter-jet?
o1
H
Figure: The near-IR images (Shibanov et al. (2003)) compared with theSpitzer data. The pulsar counterpart is marked by a tick line and thearrow shows the direction of its proper motion.
Identification of the Geminga pulsar
54.8 54.4 6:33:54.0 53.6
22.0
18.0
14.0
17:46:10.0
06.0
RA
psr
4.5 microns
54.8 54.4 6:33:54.0 53.6
25.0
20.0
15.0
10.0
05.0
17:46:00.0
RA
Dec
psr
3.6 microns
54.8 54.4 6:33:54.0 53.6
22.0
18.0
14.0
17:46:10.0
06.0D
ec
psr
I
54.8 54.4 6:33:54.0 53.6
25.0
17:46:20.0
15.0
10.0
05.0
F160W
psr
Figure: The Spitzer images vs the Subaru and HST ones (Shibanov et al.(2006)). The cross marks the pulsar position at the epoch the I-bandimage was obtained in. A tick line and the arrow marks the pulsarposition and the direction of its proper motion.
Outline
IntroductionThe Crab pulsarThe AXPsVela and Geminga
ResultsIdentification of the pulsars in mid-IRPhotometry
DiscussionThe dust discAn unresolved PWN structure
Conclusions
Crab, Vela and Geminga
0
1
2
Log
Fν
[ µJy
]
Js
U
BF67
5WF81
4W
G140
13 13.5 14 14.5 15Log ν [ Hz ]
-1
0
1
2 Geminga
24 µm
3.6 µm
4.5 µm
5.8 µm
8 µm
Spitzer/MIPS
F160W
F110W
I R
F555W
F430WF34
2W
F195F25
S
3
3.5
4
Vela
Crab
Spitzer/IRAC
K H J
Unabsorbed spectra of the Crab,
Vela and Geminga pulsars from the
mid-IR to the optical-UV. Crab:
optical and near-IR (Sandberg &
Sollerman (2009)); mid-IR (Temim
et al. (2009)); Vela: UV, optical,
near-IR (Romani et al. (2005),
Mignani et al. (2007), Shibanov et
al. (2003)); Geminga: UV,
optical/near-IR (Kargaltsev et al.
(2005), Shibanov et al. (2006));
optical spectrum (Martin et al.
(1998))
Multiwavelength spectrum: Vela
9 12 15 18 21 24 27Log ν [ Hz ]
-9
-6
-3
0
3
6L
og F
ν [
µJy
]
Chandraatm+PL
RXTE
OSSECOMPTEL
EGRET
VLT+HST+NTT
Spitzer (IRAC + MIPS)
Fermi LAT
-9 -6 -3 0 3 6 9Log E [ keV ]
Vela
Figure: The mid-IR fluxes are marked by a red circles.
Multiwavelength spectrum: Geminga
9 12 15 18 21 24 27Log ν [ Hz ]
-9
-6
-3
0
3
66L
og F
ν [
µJy
]
-9 -6 -3 0 3 6 9Log E [ keV ]
Geminga
radio, upper limits
radio, M&M
Tata group
Whipple
EGRET, α = −0.5
OSSECOMPTEL
OSSE
RXTE
hard BB
soft BB
PL
NIR+optical+FUV
Spitzer (IRAC + MIPS)
Chandra
Fermi-LAT
PL+sBB+hBB
Figure: The mid-IR fluxes are marked by a red circles.
Outline
IntroductionThe Crab pulsarThe AXPsVela and Geminga
ResultsIdentification of the pulsars in mid-IRPhotometry
DiscussionThe dust discAn unresolved PWN structure
Conclusions
Possible contribution from the dust disc
13 13.5 14 14.5 15Log ν [ Hz ]
-1
0
1
2
Log
Fν [
µJy
]
Vela
irradia
ted d
isk
power-law,α = 0.01
Rin = 0.28 +/- 0.05 R
sun
Tin = 834 +/- 63 K
irradiated disk:
Rex = 1.4 +/- 0.4 R
sun
Figure: The spectral fit of the Vela pulsar optical/IR SED by irradiatedpassive dust disc model (Vrtilek et al. (1990)). The solid line is thebest-fitting result and the hatched region shows 1σ uncertainty of the fit.Here we assume that the mid-IR pulsar fluxes are described by power-lawextrapolated from the optical-UV range.
Multiwavelength spectrum of Vela + disc
9 12 15 18 21 24 27Log ν [ Hz ]
-9
-6
-3
0
3
6L
og F
ν [
µJy
]
Chandraatm+PL
RXTE
OSSECOMPTEL
EGRET
VLT+HST+NTT
Spitzer (IRAC + MIPS)
Fermi LAT
-9 -6 -3 0 3 6 9Log E [ keV ]
Vela
Figure: The same spectral fit as seen on the multiwavelength spectrum.
Outline
IntroductionThe Crab pulsarThe AXPsVela and Geminga
ResultsIdentification of the pulsars in mid-IRPhotometry
DiscussionThe dust discAn unresolved PWN structure
Conclusions
The Vela PWN at near-IR
Figure: The near-IR image of the Vela PWN (Shibanov et al. (2003)).The pulsar and the PWN features, o1 and counter-jet, are marked by theblue and red arrows consequently.
Whether the PWN structures can contribute significantly?
13 13.5 14 14.5 15Log ν [ Hz ]
-1
0
1
2
Log
Fν [
µJy
]
o1, a PWN knot?
Vela
SE-feature, a PWN counter jet?
The fluxes of the PWN features, named o1 and conter-jet, are shown. If
we extrapolate two point near-IR spectra of the features to mid-IR band,
so we find that in mid-IR the fluxes of the features must be of same order
as the pulsar fluxes. Bear in mind possible variability of the counter-jet
we may conclude that this features can, at least partially, explain the
observed excess.
Conclusions
◮ The detections of the Vela and Geminga pulsars as well asrecent detections of several Crab-like PWNe (B0540, B1124,3C 58 and G21.5) reveal strong emission excess in the mid-IRband, that was rather difficult to expect in advance.
◮ The question arise: What is the nature of the exesess? Is itthe sign of the hypothetical fall-back discs?
◮ Further studies of these and other pulsars in the mid-IR andespecially submillimetre bands are necessery to get the answer.
Conclusions
◮ The detections of the Vela and Geminga pulsars as well asrecent detections of several Crab-like PWNe (B0540, B1124,3C 58 and G21.5) reveal strong emission excess in the mid-IRband, that was rather difficult to expect in advance.
◮ The question arise: What is the nature of the exesess? Is itthe sign of the hypothetical fall-back discs?
◮ Further studies of these and other pulsars in the mid-IR andespecially submillimetre bands are necessery to get the answer.
Conclusions
◮ The detections of the Vela and Geminga pulsars as well asrecent detections of several Crab-like PWNe (B0540, B1124,3C 58 and G21.5) reveal strong emission excess in the mid-IRband, that was rather difficult to expect in advance.
◮ The question arise: What is the nature of the exesess? Is itthe sign of the hypothetical fall-back discs?
◮ Further studies of these and other pulsars in the mid-IR andespecially submillimetre bands are necessery to get the answer.
Thank you!
The Vela PWN
The mid-IR image incomparison with theChandra one (Helfand etal. (2001)). There is nocounterpart of the X-raytorus-like structure in themid-IR.
The Vela Plerion
40.0 30.0 20.0 10.0 8:35:00.0 50.0 40.0 34:30.0
06:00.0
08:00.0
-45:10:00.0
12:00.0
14:00.0
16:00.0
18:00.0
20:00.0
RA
HRC-I 0.3-10 keV
50.0 40.0 30.0 20.0 10.0 8:35:00.0 50.0 40.0 34:30.0
06:00.0
08:00.0
-45:10:00.0
12:00.0
14:00.0
16:00.0
18:00.0
20:00.0
RA
Dec
IRAC 8 micron
Figure: The large scale structure of the Vela PWN at 8 µm and softX-rays. East boundary of the X-ray plerion correlate with the westboundary of the a brigth extended emission visible in mid-IR.
The Geminga PWN
Figure: Comparison of the mid-IR and HST/NICMOS near-IR (Shibanovet al. (2006)) images with the Chandra ones (Pavlov et al. (2010)).
The Geminga PWN
SPITZER / IRAC 3.6 micron
3" 0.5"
HST / NICMOS 1.6 micron
0.3-10 keVChandra / ACIS-I
5"
0.8 micronSUBARU / I-band
1"
Figure: The transformation of the compact PWN from X-rays, throughoptical/near-IR, to the mid-IR.
Large-scale PWN structure
55.0 54.5 54.0 53.5 6:33:53.0 52.5 52.0 51.5
30.0
25.0
20.0
15.0
10.0
05.0
17:46:00.0
55.0
50.0
45.0
RA
Dec
5.8 micron
C
BY
s2
s1
54.5 54.0 53.5 6:33:53.0 52.5 52.0 51.5
25.0
20.0
15.0
10.0
05.0
17:46:00.0
55.0
45:50.0
RA
ACIS-I
C
BY
s2
s1
Figure: The extended tail at 5.8 µm and X-rays.