HETE-2 (High Energy Transient Explorer) a small

HETE-2
(High Energy Transient Explorer)
a small satellite for studying
the cosmic gamma-ray bursts
and beyond ….
Atsumasa Yoshida (RIKEN)
HETE history
 1983— recommended in Santa Cruz meeting
 Feb 1991— official start of HETE
 US - Japan - France collaboration
 multiwavelength study of GRB in UV, X-ray and gamma-ray
 real-time localization and rapid notification
 Nov 1996— HETE-1 launch:
 lost in failure of 3rd stage separation
 Feb 1997— Discovery of GRB afterglow
 HETE concept proven, (but by different mission)
 Jul 1997— HETE-2 started
 UV camera replaced by Soft X-ray Camera in HETE-2
HETE-1
HETE-1 mounted on the Pegasus rocket.
The small red object immediately to the left of
the solar panel is a set of pyrotechnic bolt
cutters, which releases the satellite from the
third stage. The second and third stages of
the rocket can be seen.
HETE-1
3rd stage + HETE + SAC-B attached.
The third stage is the short, black unit behind the DPAF can (along
with the instrumentation ring and RCS systems ring), attached to the
white second stage. This assembly is still circling the earth as one
unit, after failure of the 3rd stage pyrotechnics to release both
satellites.
HETE-1 inside the DPAF (Dual Payload
Attachment Fitting) can.
This structure protects HETE-1 while SACB is deployed.
HETE-1
Launch in November 1996 ... and Lost
HETE-2 Instruments
The HETE Mission
 Prime objective: multiwavelength study of gamma ray
bursts (GRBs) with soft/medium X-ray, and gamma ray
instruments
 Unique feature: capability to localize bursts with
several arcsecond accuracy, in near real-time aboard
the spacecraft
 GRB positions transmitted to the global network of
primary and secondary ground stations, enabling
sensitive follow-up studies
Primary Science Goals: GRBs
 provide accurate postions (±10 arcsec to ±10 arcmin) for ~30 bursts
in real time each year.
 factor of ~4 more sensitive than the BATSE SDs for low energy
spectral features and will provide ~25 GRBs per year on which
high-quality spectral studies can be performed.
 The 2-25 keV and 3-400 keV sensitivities of the X-ray and gamma
ray instruments: effective for studying cyclotron lines and spectra of
GRBs at low energies.
 ~7.5 times more sensitive than BATSE to bursts from Soft Gamma
Ray repeaters: event rate ~ 55 times higher than BATSE.
Secondary Science Goals
 detect as many as 500-1000 X-ray bursts per year.
 monitor the evolution of X-ray bursts and X-ray
transients in the FOV of the X-ray detector.
 discover and study X-ray pulsars for ~2 month
intervals.
 discover and study black hole transients .
Spacecraft Specification
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Mass:
Envelope:
Desired orbit:
Operating life:
Attitude:
126 kg.
Fits within cylinder 89cm x 66 cm dia.
600 km circular, 0 degree inclination
6 months, nothing to preclude 2+ years
Sun pointing. Momentum bias. Attitude controlled to
+/- 2 degrees
Data processing:
Multi-processor, 80 VAX MIPS
Data Buffering:
96 MBytes of EDAC mass memory
Downlink:
250 kbits/sec data rate with overall bit error rate <2e-8 from
data storage to ground archive.
Uplink:
31.25 kbits/sec data rate, overall bit error rate < 1e-8
Radio Frequencies:
S-band uplink (2.092 GHz) and
downlink (2.272 GHz) for primary groundstation(s),
VHF downlink only (137.9622 MHz) for secondary stations.
FREnch GAmma-ray TElescope
(FREGATE)
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Built by
Instrument type
Energy Range
Timing Resolution
Spectral Resolution
 Effective Area
 Sensitivity (10 s)
 Field of View
CESR (France)
NaI(TI);cleaved
6 keV to > 1 MeV
4 ms
~40% @ 6 keV
~7% @ 662 keV
120 cm2
3x10–8 erg cm–2 s–1
over 8 keV—1 MeV
~2p sr
Wide-field X-ray Monitor (WXM)
 Built by
 Instrument type
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RIKEN and Los Alamos National Laboratory
Coded Mask with
Position Sensitive Proportional Counter
Energy Range
2 to 25 keV
Timing Resolution
1 ms
Spectral Resolution
~15% @ 6 keV
Detector Quantum Efficiency
90% @ 5 keV
Effective Area
~200 cm2 for each of two units
Sensitivity (10 s)
~8x10–9 erg cm–2 s–1
over the 2-10 keV range
Field of View
~2 sr (total for 4 units)
Angular resolution (1 s)
±6 arcmin
WXM
 Two-layered multi-wire
proportional counter
 Be window
 10m m carbon wire
 Gas mixture: Xe (97%)
+CO2 (3%)
 Gas pressure 1.4atm
GRB localization with
1-D position sensitive detectors
mask pattern
(top view)
coded mask
}
WXM
(side view)
1-dim. PC
shift pattern A
shift pattern B
shift pattern C
WXM localizes GRB's by measuring the mask
pattern displacement for two orthogonal directions.
Soft X-ray Camera (SXC)
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Built by
Instrument type
Camera dimensions
Energy Range
Timing Resolution
Spectral Resolution
MIT CSR
4 CCD20 Detectors, 2 optical CCD22
10cmx10cmx17.5cm
500 eV to 14 keV
~1 s
46 eV @ 525 eV,
129 eV @ 5.9 keV
Detector Quantum Efficiency
93% @ 5 keV,
>20% (0.5-14 keV)
Effective Area
6.1x6.1 cm2 (each of 2 units)
Burst Sensitivity (4 s)
0.47 cts cm–2 s–1
Steady source Sensitivity (4 s)
~700 mCrab x t –1/2
Field of View
0.91 sr
Focal Plane scale
33" per CCD pixel
Loaclization Precision Faint Burst, 5 s - 15",
Bright burst, 22 s, 3"
(1 Crab; 10s)
HETE2 Operation Network
Gamma Ray Burst
Primary
Ground
Station
RIKEN
S band
HETE-2
Data &
Command
GRB position
information
MIT
VHF
Ground-based Observatory
(Optical, Radio, γ-ray )
Internet
Secondary
Ground
Station
Secondary Ground Station Network
5
2
3
4
9
7
6
1 Kwajalein *
167.7 E
2 Christmas Island
W 1.9 N
3 Hiva Oa (French Polynesia)
W 9.8 S
4 Galapagos Island (Ecuador) 91.1 W
5 Cayenne (French Guiana) *
51.9 W
6 Natal (Brazil)
W 5.5 S
7 Accra (Ghana)
0.2 W
8 Malindi (Kenya)
E 3.0 S
* 9Primary
Ground Station
Male (Maldives)
E 3.6 N
8
8.7 N
157.1
139.0
0.7 S
4.9 N
35.1
5.6 N
40.2
73.7
11
10
1
Vibration Test
Lincoln Lab - MIT
August 1999
Thermal Vacuum Test
Lincoln Lab - MIT
August-September 1999
Primary Ground Station
in Singapore
National University of Singapore
Launch in January 2000
 The HETE-2 is scheduled to be launched in January
2000 from Kwajalein, Republic of the Marshall Islands.
ROTSE
Robotic Optical Transient Search Experiment
University of Michigan.
Los Alamos National Laboratory
Lawrence Livermore National Laboratory
OPTICS
Canon 200 mm focal
length, f/1.8, telephoto
lenses in FD mounts
IMAGER
Apogee Instruments AP-10
CCD cameras with
Thomson 2048 x 2048 14
micron imagers.
Estimated readout noise:
25 e- at 1.0
Megapixels/sec.
Optical Flash!
Up to 9 mag
UTC
9:47:18.3
9:47:43.5
9:47:08.8
9:51:37.5
9:54:22.8
9:57:08.1
exposure
m_v
5 secs. 11.82
5 secs. 8.95
5 secs. 10.08
75 secs. 13.22
75 secs. 14.00
75 secs. 14.53
GRB 990123: Optical Transient
ROTSE
(Optical)
BATSE
(gamma-ray)
ROTSE-II
ROTSE-II is a set of twin 0.45 meter aperture,
f/1.9 telescopes to be operated in stereo mode.
Apogee Instruments AP-10 CCD cameras with
Thomson 2048 x 2048 14 micron imagers.
Estimated readout noise: 25 e- at 1.0
Megapixels/second.
LOTIS Livermore Optical Transient Imaging System
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2 x 2 array of Canon EF 200 mm
f/1.8L telephoto lenses w/ Loral
442A 2k x 2k CCDs as the imaging
sensors.
Each focal plane area of 3.1 cm x
3.1 cm --- a field-of-view for each
camera of 8.8° x 8.8°.
The total field-of-view for the
telescope array (allowing for
overlap) is therefore 17.4° x 17.4°.
The CCD pixel size of 15 μm x 15
μm results in a pixel resolution of
15 arcsec.
Super-LOTIS
 Telescope: Boller & Chivens 0.6
meter f/3.5 reflector w/ computer
controllable motor drive.
 Imager: a Loral 442A 2048 x 2048
CCD (15 x 15 micron pixels) with
LLNL built readout electronics. The
CCD is cooled with thermoelectric
cooler (to -30 degrees C).
 Field-of-View: 0.84 x 0.84 degree
field-of-view (1.5 arcsec/pixel).
 Resolution - < 1.5 arcsec
 Sensitivity - V ~ 19 (10 s), V ~ 21
(60 s) at -30 deg C
 Slew Speed - 5 deg/s
RIBOTS
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RIBOTS Specification
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望遠鏡
LX200-30 シュミットカセグレン
口
径
300mm
焦点距離
1000mm (0.33倍RD使用)
視
野
47.2 ‘X 31.4‘
導入速度
秒速6°
冷却ＣＣＤ
ST8E (KAF1600E)
画素数
1530x1020 (160万画素)
２×２：７６５×５１０角度分解能３．７“
３×３：５１０×３４０角度分解能５．６“
波長帯
350～925nm (QE > 20%)
フィルターなし
Swift
Catching Gamma Ray Bursts on the Fly
Multiwavelength gamma ray
burst observatory
Science
Determine origin of GRBs
Use GRBs to probe the early
Universe
Three instruments
Gamma-ray camera
X-ray Telescope
UV and Optical Telescope
Rapidly re-pointing “swift”
spacecraft
20-70 s response
Swift Mission Features
 Multi-wavelength observatory
 Burst Alert Telescope (BAT): 10-150 keV
detect ~ 300 gamma ray bursts per year
onboard computation of positions
arc-minute positional accuracy
 Dedicated telescopes for X-rays, UV, and optical
afterglow follow up:
0.3-10 keV X-ray Telescope (XRT)
170-650 nm UV/Optical Telescope (UVOT)
Rapid response satellite
0.3-2.5 arc-second locations
20 - 70 sec to slew within FOV of BAT
existing hardware from JET-X and XMM
determine redshifts from X-ray absorption,
autonomous operations
factor 100 improved response time lines, and Lyman- cutoff
continue monitoring of fading afterglow
Swift Instrumentation
Burst Alert Telescope (BAT)
 Real time gamma ray burst positions
half coded FOV 2 steradians
5200 cm2 CdZnTe pixel array
10-150 keV band
based on Integral Imager design
5 times more sensitive than BATSE
~ 1 burst per day detected
(depends of logN-logS extrapolation)
angular resolution of 22 arcmin giving
positions of 1-4 arcmin
onboard processing to provide prompt arcminute position to satellite ACS and to the
ground
BAT CdZnTe
detector module
Swift mission summary
 PI: N. Gehrels (GSFC)
 Narrow Field Instruments - Penn State lead
• X-ray Telescope & Focal Plane (XRT) - Penn State/Leicester/Brera
• UV/Optical Telescope (UVOT) - MSSL/Penn State/UCSB
 Burst Alert Telescope (BAT) - GSFC lead
• Camera and mask - GSFC
• Onboard processing - Los Alamos
 LEO orbit, 600 km circular 19 degree inclination
 Launch date 2003
 Three-year mission operation life
 Orbit stable for 5+ years without propulsion
Space Missions Capable of
Localizing Gamma-Ray Bursts
Mission
loc/yr
accuracy
delay
operating period
BeppoSAX
10
1—10 arcmin
hours
present — 2001?
CGRO BATSE
300
100
70
>4°
>1.6°
5’x 10°
5 sec
15 min
~1 day
1’x 20’
present — 2002?
RXTE ASM
4
10 arcmin
hours
present — 2002?
HETE-2 WXM
SXC
30
16
10 arcmin
10 arcsec
~10 sec
2000 —2001
INTEGRAL IBIS
20
arcminutes
~10 sec
2001—2003
Swift BAT
XRT
UVOT
300
1—4 arcmin
~arcsec
0.3 arcsec
12 seconds
50—70 sec
200 sec
2003(2004)—2010
50
(200)
10 arcmin
(arcmin-arcsec)
Interplanetary
network (IPN）
GLAST (>100 MeV)
(GBM)
present —2001?
2005—
(10—300 sec)

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