INTEGRAL衛星の初期成果

INTEGRAL衛星の初期成果
海老沢 研
INTEGRAL Science Data Center
Versoix, Switzerland
Contents
 Introduction of the satellite
 Introduction of the instruments
 Status and performance of the
instruments
 Early scientific results
 Current problems
 Prospects for future
INTEGRAL satellite
 Launched on Oct 17,
2002 by Russian
Proton rocket
 Covers 3 keV to ~10
MeV with three coded
mask instruments
 Hard X-ray/gamm-ray
imaging
 Gamma-ray
spectroscopy
INTEGRAL Orbit
 High eccentric orbit, 72
hour period
 Inclination 51.6°
 Perigee ~9,000 km,
apogee ~150,000 km
 Two ground stations
 Goldstone (California)
 Redu (Belgium)
 REAL TIME OPERATION
 Gamma-ray burst
monitor!
INTEGRAL Detectors
JEMX masks
IBIS mask
SPI
IBIS detector
JEMXdetectors
IBIS
•
•
(Imager on Board the Integral Satellite)
Full imaging capability
FWHM~12 arcmin
Centroid accuracy ~arcmin
•
ISGRI (20-200 keV)
128x128 CdTe pixels
Moderate energy resolution (~9%@100 keV)
•
PICSIT (100-6000 keV)
64x64 CsI pixels
ISGRI (CdTe)
PICSIT(CsI)
Spectrometer SPI
• Coded mask and 19 Ge
detectors
• Stirling cryocooler
• Limited imaging
capability(19 “pixels”)
• BGO anti-coincidence
detectors
• High energy resolution
~2.2 keV@662 keV
• Energy range 15 keV to
8 MeV
• Anti Coincidence
Sensor (ACS)
GBD minotor!
X-ray monitor JEMX
• Two identical
detectors
• Imaging micro-strip
gas chambers(90%
Xenon + 10 %
Methane)
• Energy range 3-35
keV
• ~30’’ angular
resolution
INTEGRAL prelaunch movie
IBIS on-board sensitivity
3s, 105 sec exposure
Ubertini et al.(2003)
ISGRI
Based on measured BGD, only
statistical errors taken into account
“Ultimate sensitivity”
~1mCrab @ 20-100 keV
PICIST sources:Crab and
Cyg X-1, GRB only?
PICSIT
SPI on-board sensitivity
Roques et al. (2003)
10 mcrab
3s, 106 sec
1 mcrab
SPI point source sensitivity is limited by confusion (~0.5 deg)
JEMX on-board sensitivity
Brandt et al. (2003)
• Sensitivity limited by systematics
• Ultimate sensitivity ~1mCrab
Detectable sources
“INTEGRAL reference catalog” Ebisawa et al. (2003)
~1000 known sources, ever brighter 1mCrab above 2 keV.
Detectable
sources
•INTEGRAL has a large FOV
•Eventually, all the sky will be
fully covered
•105 sec exposure over the sky
•~700 sources with JEMX
•~400 sources with ISGRI
Ebisawa et al. (2003)
Exposure map from Oct 2002 to Nov 2003
Green> 106 sec
Blue >105 sec
3C273
Vela
Cyg
GC
Crab
LMC
2003
AO1
2004
AO2
Projects and targets
 Core program




Galactic Center Deep Exposure (GCDE)
Galactic Plane Scan (GPS)
Vela region
TOO observations for transient sources
Projects and targets
• Accepted general programs (A and B categories, besides
TOO and GRB)
–
–
–
–
–
–
–
–
–
–
AGN
Galaxy
Clusters
Galactic diffuse
G.C.
SNR
Binary
Pulsar
Stars
Gamma-ray sources
AO1
16
2
1
3
2
3
10
1
2
6
AO2
12
1
2
9
1
2
11
1
2
5
• Most AO1 observations completed, data are sent to PIs
• Calibration and analysis software getting better…
Early results
 Discovery of new sources (from GCDE, GPS)
 IAUC, Astronomer’s Telegram
 GRB detection
 GRB Coordinates Network (GCN)
 A&A special issue, 2003, vol 411, no1
 75 letter papers (28 astrophysical papers)
 5th INTEGRAL meeting in Feb 2004 (Munich)
 244 abstracts submitted (including non-INTEGRAL
papers)
 Some other publications…
INTEGRAL Sources (http://isdc.unige.ch/~rodrigue/html/igrsources.html)
15 sources till Dec 2003
IGR J16316-4028 3EG J1631-4033 (?)
IGR J16318-4848 Seen with ASCA in 1994, NH=3 x 1024 cm-2, prominent iron line
IGR J16320-4751
NH=2.1 x 1023 cm-2, AX J1631.9-4752
IGR J16358-4726
NH=3.3 x 1023 cm-2, X-ray pulsations at 5850 +/-50 s
IGRJ16479-4514
IGRJ17091-3624
1SAX J1709-36
IGRJ17391-3021
XTE J1739-302
IGRJ17456-2901
Sgr A*? or X-ray binary?
IGRJ17464-3213
H1743-322,XTE J1746-322
IGRJ17544-2619
IGRJ17597-2201
XTE J1759-220
IGRJ18325-0756
IGRJ18483-0311
IGRJ18539+0727
IGRJ19140+098
All transient sources!
IGR J16318-4848
(observed @50mCrab with INTEGRAL)
Revnivtsev et al. (2003)
ASCA
1994
~1mCrab
Walter et al. (2003)
XMM and ISGRI
Iron line
dominate!
Heavily absorbed X-ray binary transients!
(probably high mass binaries like GX301-2)
High energy imaging/spectra of binary sources
SPI energy spectrum
308
-605
keV
of Cyg X-1
20-50
84 -308
keV
keV
SPI image of the Cyg region
Moderate resolution (~0.5 deg)
imageup to ~600 keV!
Bouchet et al. (2003)
Cyg X-1
PCA
HEXTE
JEMX
ISGRI
SPI
High quality spectra of bright sources
from 3 keV to ~1 MeV!
Pottschmidt et al. (2003)
Bright X-ray binaries near GC
b
b
l
l
l
b
ISGRI 20-40 keV
ISGRI 40-60 keV
High resolution (~10 arcmin) imaging up to ~100 keV
Paizis et al. (2003)
Early results – Gamma-ray bursts
• 7 GRBs in the IBIS FOV (till Dec 2003)
– Detected with INTEGRAL Burst Alert System (IBAS)
– Alerts sent all over the world within ~10 sec
– Position accuracy depends on the brightness, down to
~30”
• SPI Anti-coincidence Sensor (ACS) alert (no
position) ~1/day
– sent to GRB Coordinates Network (GCN)
GRBs detected with IBAS
4.4’ in 30sec!
Mereghetti et al (2003)
Error region and delay
GRB detected with ACS
Light curves
Expected from BATSE
Duration histogram
von Kienlin et al. (2003)
GRB energy spectra
PICSIT
ISGRI
Malaguti et al. (2003)
Good GRB energy spectra from
20 keV to 500 keV!
GRB021125
GRB030501
ISGRI
SPI
Spectral
variation
SPI spectrum
Beckman et al. (2003)
Extragalactic sources
•Many other bright AGNs detected
(confirmed with real time Quick
Look) Publication?
•3C111 – radio galaxy at z=0.048
(~34 mCrab in the 20-40 keV
band in August 2003 (Favre et al.)
•Strong flares expected! (e.g.
Blazers)
•Normal galaxy? Clusters of
Galaxies?
3C273 detected, expected spectrum
(Courvoisier et al. 2003)
Galactic center
Belanger et al. (2003)
20 - 40 keV
40 - 100 keV
Hard X-ray point source coincides with Sgr A*
Sgr A*?
X-ray binary?
Strong et al. (2003)
Galactic diffuse emission
• Preliminery results
•Consitent with previous XTE,
OSSE observation
GC=33deg
•A rumor says…
•Contrubution of point sources at
~100 keV dominant than previous
estimates?
•Not so much Galactic “diffuse” emission
at ~100 keV?
L=33deg
Galactic center 511 keV line
Knodlseder et al. (2003)
Symmetric diffuse
distribution around GC
Annihilation fountain
(claimed by OSSE)
not confirmed
Russian data!
Current problems
• Calibration
– Background estimation, subtraction
– Spectral response
• Analysis technique
– Currently, deconvolution is made for each pointing
(~30 min), deconvolved images and spectra combined
– Photons have to be accumulated for longer periods!
– Deconvolution at once from many (~1000) pointings
– Memory and CPU serious problems…
• Data structure, software issues
– Unique data structure, incompatibility with widely-used
analysis system, difficult to handle “event” data
– No good portability of data/software
Future prospects
• Detection of more gamma-ray lines expected
– SNR, Point sources
•
•
•
•
Annihilation line from point sources?
Dim sources down to 1 mCrab at >50 keV?
High quality spectra of dim sources up to ~1 MeV
Short transients?
– Gamma-ray/X-ray “flush” events
• Fast pulsars?
– Hard X-ray study of millisecond pulsars