Download presentation
Presentation is loading. Please wait.
2
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 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
3
For the Crab, the INTEGRAL spectrum has photon index of ~2.23 i.e similar to Jet/Counterjet Spin-down energy loss, Ė = 4.6 10 38 erg s -1 L (20-100) ~ 7 10 36 erg s -1 ~1.5% Ė L 1-10TeV ~ 3.4 10 33 erg s -1 ~10 -2 % Ė HESS spectrum has ~2.39 Centroid shown PSF ~0.14 Mori et al 2004
4
Klein-Nishina cross-section for linearly polarized photons: = azimuthal scatter angle = elevation angle – azimuth angle between incident photon polarisation direction and scattered photon direction. Simulated modulation due to Compton scattering
5
“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 Chandra Spectral Images 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 Roberts et al 2003
6
INTEGRAL error circle lies within SNR 0.2-2.0 keV4.0-8.0 keV INTEGRAL/IBIS Where do the gamma-rays come from? SNR spectrum is thermal, kT~ 0.6 keV Good fit between INTEGRAL and Chandra PSR + ”jet”
7
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 10 13 G ? Chandra Spectral Images Helfand et al 2003 Youngest with longest period
8
IBIS “coincident” with Pulsar/PWN complex IBIS/ISGRI : = 2.0 includes PWN + Pulsar Ė = 8.4 10 36 erg s -1 L (20-100) = 1.3 10 36 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 Chandra-IBIS McBride et al (2007)
10
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 10 34 erg s-1 ~0.4% Ė L TeV ~ 0.5% Ė HESS image INTEGRAL image Mechanisms: X/soft -rays: synchrotron, E e ~ 10 13 -10 14 eV, ~ 500y TeV: IC on (partly) CMB, E e ~ 10 12 -10 13 eV, ~ 3-5000y 10 Gauss field
11
Youngish Vela Pulsar (89 ms, 290pc, Ė = 7x10 36 ergs -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 INTEGRAL Image Pulsar Rosat (White ) Aharonian et al 2006
12
IBIS/ISGRI : = 1.89 Fits Chandra Pulsar/PWN combo L (20-100) ~ 2.44% Ė L (1-10TeV) ~ 0.26% Ė INTEGRAL Spectrum PSR J1509-58, (5kpc, ~1500y, 150ms, Ė = 1.8x10 37 ergs -1, B=1.5 10 13 G) Chandra shows torus and & jet with pulsar + HESS Elliptically around pulsar (1st extended PWN jet seen in VHE)
13
Positional location : Tantalisingly close to pulsar, within PWN? Crab Inner Jet J0540-6919 (LMC)PWN/”jet” J0835-4519 (Vela)PWN/”jet” J1302-6350 (Be)? Be accretor J1513-5906 (MSH 15-52)PWN/”jet” J1617-5055 near pulsar (X-PWN? – No jet) J1811-1925 (Turtle)PWN/”jet” J1833-1034Somewhere in outer PWN – No jet J1846-0258 (Kes 75)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”
14
INTEGRAL NOTE: They are all young, short period (~ 100ms), energetic pulsars, spin down ages in range 700 τ 20,000 y X-rays (Possenti et al 2002) Ė 10 36 erg/s L(20-100) J0835-4519 (Vela) @ 0.02% L (20-100) %Ė) 1% 20-100 keV -rays (INTEGRAL/IBIS)
15
INTEGRAL X-rays Weighted mean 20-100 keV photon spectral index: = 2.13 ± 0.15 Γ Ė erg/s
16
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
17
High-energy spectrum of PSR J1846-0258 NOTE: As the energy increases the pulsar provides more of the output.
18
Spectral Indices Emitted Power
19
e.g. G292.0+1.8 – PSR J1124-5916 Age ~ 1600 y Distance ~ 5.4 kpc Ė ~1.2 10 37 erg/s P = 135 ms, dP/dt = 7.47 10 -13 s/s ~3 ky L (20-100)Min ~ 0.5% Ė @ 5
20
Is the Ė /D 2 too faint? NO
21
Note: a comparison with Ė is not correct Integrate Ė over electron lifetimes Some still should be there!
22
LSI +61 303, : “OFF” (phase 0.8 – 1.3) “ON” (phase 0.3 – 0.8) 20 – 95 keV > 400 GeV
23
The distant blazar Swift J1656.3-3302 z = 2.40 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.) SWIFT J1656.3-3302 Z = 2.40 Ly α CIV CIII] SIV
24
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
25
The obscured source IGR J16318-4848 NOTE: 25% of INTEGRAL sources are still unidentified.
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.