Transcript Document 7640347


The Source list of PWN:

Selection based on the Mallory Roberts The Pulsar Wind Nebula Catalogue

http://www.physics.mcgill.ca/~pulsar/pwncat.html

Interest heightened by the association with a number of HESS Sources

Three types of PWN for IBIS/ISGRI:

Seen by IBIS - some discussed here ~ 10 (16%)

Pulsar seen in radio but not seen by IBIS ~ 25 (42%)

No radio pulsar ~ 25 (42%) – Possibly one seen by IBIS
For the Crab, the INTEGRAL spectrum has
photon index of ~2.23
i.e similar to Jet/Counterjet
Mori et al 2004
Spin-down energy loss, Ė = 4.6  1038 erg s-1
L(20-100) ~ 7  1036 erg s-1 ~1.5% Ė
L1-10TeV ~ 3.4  1033 erg s-1 ~10-2 % Ė
HESS spectrum has
~2.39
Centroid shown
PSF ~0.14
Klein-Nishina cross-section for linearly polarized photons:
2
0
dσ r

dΩ 2
'
'
 E E E
2
2 
   '  2sin θcos  
 E  E E

 = azimuthal scatter angle
 = elevation angle
 – azimuth angle
between incident
photon polarisation
direction and
scattered photon
direction.

Simulated modulation due to
Compton scattering
Chandra Spectral Images
 “Classic” SNR/PWN/Pulsar configuration
 4’5 diameter SNR has thermal kT ~ 0.6 keV
 65ms Pulsar has  ~ 0.97
 Bilateral elongated PWN has  ~ 1.8
Roberts et al 2003
 Blobs move along jet with ~ 1.4c and 0.8c
 IBIS/ISGRI :  = 1.8 like Chandra PWN
 L (20-100) ~ 0.66% Ė @ 5 kpc
Where do the gamma-rays
come from?
 INTEGRAL error circle lies within SNR
INTEGRAL/IBIS
0.2-2.0 keV
4.0-8.0 keV
 SNR spectrum is thermal, kT~ 0.6 keV
 Good fit between INTEGRAL and
Chandra PSR + ”jet”
Chandra Spectral Images
 Very young (~700y) system @ 19kpc
 P = 324 ms
 dP/dt = 7.1  10 -12 ss -1
 PWN/PSR close to centre of composite SNR
 SNR, thermal, kT ~ 2.9 keV
 Pulsar has  ~ 1.39
 Axisymmetric elongated PWN has  ~ 1.92
 Hot spots along axis on either side of pulsar
 Exceptional timing properties : P & dP/dt > 10 Crab
 Result of extreme B value of 4.8 1013 G ?
Helfand et al 2003
Youngest with longest period
IBIS-ISGRI
Chandra
50”
Chandra-IBIS
McBride et al (2007)
 IBIS “coincident” with Pulsar/PWN complex
 IBIS/ISGRI :  = 2.0  includes PWN + Pulsar
 Ė = 8.4  1036 erg s-1
 L (20-100) = 1.3  1036 erg s-1 @ 19kpc
 Extraordinary L (20-100) ~ 15% Ė !!! – But some concerns over 19 kpc
 With D ~ 6 kpc, L (20-100) ~ 1.5% Ė
 L(1-10TeV) ~ 0.1% Ė
HESS image
INTEGRAL image
 HESS extended and one sided, source size decreases with E
 INTEGRAL, point like, coincident with 69ms PSR
 Soft γ-ray emission Γ = 1.91
 L(20-100) = 7.4  1034 erg s-1 ~0.4% Ė
 LTeV ~ 0.5% Ė
Mechanisms:
 X/soft -rays: synchrotron, Ee ~ 1013 -1014 eV,  ~ 500y
 TeV: IC on (partly) CMB, Ee ~ 1012 -1013 eV,  ~ 3-5000y
 10 Gauss field
Aharonian et al 2006
Pulsar
Rosat (White)
INTEGRAL
Image
Youngish Vela Pulsar (89 ms, 290pc, Ė = 7x1036ergs-1,  ~ 11ky)
 HESS extended source south of pulsar (B0833-45)
 Rosat/ASCA Vela X jet like feature corresponds to a one-sided PWN
 No IBIS excess from extended PWN,
 No HESS excess from pulsar
 L(20-100) ~ 1.6 10-2 % Ė
 L(1-10TeV) ~ 0.6 10-2 % Ė
 PSR J1509-58, (5kpc, ~1500y, 150ms, Ė =
1.8x1037ergs-1,
B=1.5
1013G)
INTEGRAL Spectrum
 IBIS/ISGRI :  = 1.89
Chandra shows torus and & jet with pulsar +  Fits Chandra Pulsar/PWN combo
 L(20-100) ~ 2.44% Ė
 HESS Elliptically around pulsar (1st
 L(1-10TeV) ~ 0.26% Ė
extended PWN jet seen in VHE)
 Positional location : Tantalisingly close to pulsar, within PWN?
 Crab
 J0540-6919 (LMC)
 J0835-4519 (Vela)
 J1302-6350 (Be)
 J1513-5906 (MSH 15-52)
Inner Jet
PWN/”jet”
PWN/”jet”
? Be accretor
PWN/”jet”
 J1617-5055
 J1811-1925 (Turtle)
 J1833-1034
 J1846-0258 (Kes 75)
near pulsar (X-PWN? – No jet)
PWN/”jet”
Somewhere in outer PWN – No jet
PWN/”jet”
 IBIS Site must be close to electron accelerator
 Synchrotron lifetime of soft -ray producing electrons in PWN fields is
 ~ 10 - 100y
 NOTE that  67% of the soft -emitting systems have “jets”
INTEGRAL
L(20-100)
20-100 keV -rays
(INTEGRAL/IBIS)
Ė 1036 erg/s
NOTE: They are all young,
short period (~ 100ms),
energetic pulsars, spin down
ages in range
700  τ  20,000 y
1%
L(20-100) %Ė)
X-rays
(Possenti et al 2002)
J0835-4519 (Vela) @ 0.02%
Soft
gamma
spectral
index
Spectral
Index vs
Edot
10
3.5
Γ
2.5
Photon Index
number per bin
3
2
1
Spectral Index
Frequency
1.5
1
0.5
0
0.1
1E+35
1
1.2
1E+36
1.4
1.6
1.8
1E+37
2
2.2
1E+38
2.4
Edot erg/s
2.8
Ė2.6erg/s
1E+39
3
More
Soft gamma photon index
INTEGRAL
Weighted mean 20-100 keV
photon spectral index:
 = 2.13 ± 0.15
X-rays
 A young energetic pulsar is needed
 L(20-100) ~ 1% Ė, & L(20-100keV)  L(1-10TeV)
 A jet-like feature is generally present
 The soft gamma-ray photon index is  ~ 2
 INTEGRAL source is “coincident” with the
pulsar/PWN & INTEGRAL  X-rayPWN
 When accompanied by a TeV source, Synchrotron for
soft gammas and Inverse Compton for TeV works well.
 NOTE the energies of the soft gamma producing
electrons is ~ 10× TeV producing electrons
High-energy spectrum of
PSR J1846-0258
NOTE: As the energy increases the pulsar provides more of the output.
Soft gamma spectral index
TeV spectral indices
3.5
4.5
4
3
2.5
Frequency
2
1.5
number per bin
3
2.5
2
Freq
1.5
1
1
0.5
0.5
0
0
1
1.2
1.4
1.6
1.8
2
2.2
2.4
2.6
2.8
3
1
More
1.2
1.4
1.6
1.8
2
Spectral Indices
LSG/LTeV vs Age
1000
100
10
Series1
1
0.1
0.1
2.2
2.4
Soft gamma photon index
Spectral Index
LSG/LTeV
Number per bin
3.5
1
10
Age ky
Emitted Power
100
2.6
2.8
3
More
e.g. G292.0+1.8 – PSR J1124-5916
 Age ~ 1600 y
 Distance ~ 5.4 kpc
 Ė ~1.2 1037 erg/s
 P = 135 ms,
 dP/dt = 7.47 10-13 s/s
  ~3 ky
L(20-100)Min ~ 0.5% Ė @ 5
L(20-100)/Edot, no resevoir
2.5
1.5
+gamma
1
Is the Ė /D2 too faint?
0.5
500
250
100
50
25
10
5
2.5
1
0.5
0.25
0.1
0.05
0.05
L(20-100)%Edot
Lmin(20-100)/Edot, no resevoir
6
5
4
3
-gamma
2
1
Lmin(20-100)%Edot
50
10
0
25
0
50
0
10
00
25
10
5
1
2.
5
0
0.
01
0.
02
5
0.
02
5
0.
05
0.
05
0.
1
0.
25
0.
5
NO
Number per Bin
0.03
0.03
0
0.01
Number per Bin
2
Note:
3.5
3
2.5
2
1.5
1
0.5
0
10
0
25
0
50
0
10
00
50
25
5
10
a comparison with Ė is
not correct
1
2.
5
0.
01
0.
02
5
0.
05
0.
1
0.
25
0.
5
Number per Bin
L(SumEdot for T) Gamma PWN
L(20-100)/L(T)
 Integrate Ė over
electron lifetimes
L Sum EdotT No Gamma
5
4
3
2
1
Lmin(20-100)/L(T)
50
10
0
25
0
50
0
10
00
25
10
5
2.
5
1
0.
5
0.
1
0.
25
0.
02
5
0.
05
0
0.
01
Some still should be there!
Number per Bin
6
LSI +61 303, :
“OFF” (phase 0.8 – 1.3)
“ON” (phase 0.3 – 0.8)
20 – 95 keV
> 400 GeV
The distant blazar Swift J1656.3-3302
Data analysis of spectroscopy collected with the ESO-3.6m
telescope plus EFOSC2 on June 2007 allowed us to identify the
hard X-ray source Swift J1656.3-3302 as a powerful gamma-ray
loud blazar at z = 2.40.
This is, up to now, the farthest optically-identified object of any
INTEGRAL survey, and the fourth farthest of all objects
detected with INTEGRAL.
Masetti et al. (in prep.)
Z = 2.40
Lyα
CIV
SIV
CIII]
SWIFT J1656.3-3302
IGR J16479-4514, the 9th SFXT
Optical counterpart recently identified as supergiant (Chaty 2007,astroph 0710.0292)
SFXT with the highest duty cycle (Sguera et al. 2007 to be submitted)
ISGRI light curve (18-60 keV) from Feb 2003 to Apr 2006
bin time 2000 s
The obscured source IGR
J16318-4848
NOTE: 25% of
INTEGRAL sources
are still unidentified.