| Satellite | Instrument | E band [keV] |
Spatial | Spectral resolution1 [eV] at: | Time resol.2 | Effective area3 [cm2] at: | Notes | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Field of view | Resol. (FWHM) | .1 keV | .5 keV | 1 keV | 6 keV | .1 keV | .5 keV | 1 keV | 6 keV | 20 keV | |||||
| Uhuru 1970-75 1st dedicated satel. |
2-20 | 1°×10° | -- | -- | -- | 840 | 840 | PC, collimated; survey | |||||||
| HEAO-1 1977-79 1st large satellite |
LASS (A-1) | 1-20 | few° | -- | -- | -- | -- | 10000 | 10000 | 10000 | PC; large area sky survey | ||||
| CXE (A-2) |
0.2-60 | few° | -- | -- | 4000 | 4000 | 4000 | 4000 | PC; cosmic X-ray background exp. | ||||||
| MC (A-3) | 1-20 | few° | ~1' | -- | -- | -- | -- | -- | -- | scanning MC | |||||
| (A-4) | 15-104 | 1°×20° | -- | -- | -- | -- | -- | -- | -- | -- | 200 | collimated | |||
| Einstein (HEAO-2) 1978-81 1st imaging telescope |
IPC | 0.3-3.5 | 75' | 1' | -- | -- | -- | ~100 | -- | -- | PC | ||||
| HRI | 0.2-3.0 | 25' | 4" | -- | -- | -- | -- | -- | 5-20 | -- | -- | MCP; Optional grating yields 2% E resol. | |||
| SSS | 0.5-4.5 | 6' | -- | -- | E/dE=3-25 | -- | -- | ~200 | -- | -- | solid state spec | ||||
| FPCS | 0.4-2.6 | 6' | -- | -- | 3 | -- | -- | 0.1-1.0 | -- | -- | Bragg crystal spec | ||||
| MPC | 2-15 | 1.5° | -- | -- | -- | 1200 | -- | -- | -- | 700 | -- | PC w/o telescope | |||
| Tenma (Astro-B) 1983-85 | PCs | 2-60 | ~3° | -- | 550 FWHM | -- | -- | -- | 640 | 10 GSPCs; varied fov | |||||
| telesc. | 0.1-2.0 | 0.2×5° | -- | ~14 | -- | -- | 2 non-imag telescopes | ||||||||
| EXOSAT 1983-86 |
ME | 1-50 | 0.75° | -- | -- | -- | -- | -- | ~1600 | PC | |||||
| LE+CMA | .05-2.0 | 2° | 18" | -- | -- | -- | telescopic; gratings avail. | ||||||||
| LE+PSD | telescopic | ||||||||||||||
| GS | 2-20 | -- | -- | -- | -- | -- | -- | -- | ~100 | GSPC | |||||
| Ginga (Astro-C) 1987-91 | LAC | 1.5-37 | 0.8×1.7° | -- | -- | -- | -- | ~1200 | 0.98ms | -- | -- | -- | ~4000 | Columnated PC | |
| ASM | 1-20 | 1×180° | -- | -- | -- | -- | -- | ~70 | All-sky monitor | ||||||
| GBD | 1.5-500 | 4π sr | -- | -- | -- | -- | -- | -- | -- | ~60 | GRB detector | ||||
| BBXRT 2-11 Dec 1990 |
0.3-12 | 17.4' | 4' diam. pixel | -- | 85 | 90 | 150 | -- | ~40 (A0+B0) | ~200 (A0+B0) | ~190 (A0+B0) | -- | 5 pixel ccd; ×2 (A&B); shuttle (Astro-1) | ||
| ROSAT 1990-99 |
HRI | 0.1-2.4 | 20'×20' | 5" | -- | -- | -- | -- | ~10 | 80 | -- | -- | MCP | ||
| PSPC | 0.1-2.4 | 114' | 15" | -- | ~380 | 500 | -- | ~40 | 210 | -- | -- | Imaging PC, ×2 | |||
| ASCA (Astro-D) 1993-00 |
SIS | 0.4-10 | 22'×22' | 1' | -- | 50-100 | 70-140 | 120-320 | 4s4 | -- | 80 | 260 | 210 | -- | 2×2 ccd array; ×2 |
| GIS | 0.7-10 | 50' | 3' | -- | -- | 190 | 460 | 60us | -- | -- | 100 | 250 | -- | GSPC; ×2 | |
| BeppoSAX 1996-02 |
LECS | 0.1-2 | 37' | 2-3' | -- | 125 | 190 | 530 | 16us | -- | 4 | 25 | 35 | -- | GSPC, 14" pixels |
| MECS | 1.3-10 | 28' (r) | 2-3' | -- | -- | -- | 480 | 15us | -- | -- | -- | 100 | -- | ×2; GSPC; 20" pixels | |
| HPGSPC | 3-120 | 1.1° | -- | -- | -- | -- | 600 | -- | -- | -- | 150 | 260 | GSPC | ||
| PDS | 15-300 | 1.4° | -- | -- | -- | -- | -- | 16us | -- | -- | -- | -- | 500 | scinillator shields are 60-600keV GRB mntr | |
| WFC | 1.8-28 | 20°×20° | 5' | -- | -- | -- | 1200 | -- | -- | -- | 100 | ~70 | ×2; CM PCs | ||
| Astro-E 10 Feb 2000 R.I.P. |
XRS | 0.4-10 | 4'×2' | 1.5' | -- | 12 | 12 | 12 | -- | 150 | 130 | -- | Microcalorimeter; cryogenic (2yr) | ||
| XIS | 0.4-10 | 19'×19' | 1.5' | -- | ~35 | ~50 | 130 | -- | 300 | 250 | -- | 1 ccd/mirror (×4) | |||
| HXD | 10-700 | 4 Pi | -- | 30% (10keV); 9% (662keV) | -- | -- | -- | -- | 230 | 16 columnated | |||||
| Satellite | Instrument | E band [keV] |
Spatial | Spectral resolution1 [eV] at: | Time resol.2 | Effective area3 [cm2] at: | Notes | ||||||||
| Field of view | Resol. (FWHM) | .1 keV | .5 keV | 1 keV | 6 keV | .1 keV | .5 keV | 1 keV | 6 keV | 20 keV | |||||
| RossiXTE 1995- |
PCA | 2-60 | 1° | -- | -- | -- | -- | 1125 | 1us | -- | -- | -- | 5000 | ||
| HEXTE | 15-250 | 1° | -- | -- | -- | -- | 8us | -- | -- | -- | -- | ~1600 | 4 SC cluster (×2) | ||
| ASM | 2-10 | -- | -- | -- | -- | -- | -- | -- | |||||||
| Chandra (AXAF) 1999- |
HRC-I | .08-10 | 31'×31' | <0.4" | 80 | 16us | 10 | 65 | 225 | 40 | -- | 90×90mm MCP | |||
| HRC-S | .08-6 | 7'×97' | 0.1 | 1.3 | 5 | 180 | 8 | 10+11 | 20+10 | 5 | -- | 20×300mm MCP; uses LETG | |||
| ACIS-I | 0.2-10 | 16'×16' | 1-2" (0.49" pix) |
-- | 50(FI)/ 115(BI) | 55(FI)/ 125(BI) | 130(FI)/ 190(BI) | 3.3s | -- | 110/FI, 400/BI | 410/FI, 800/BI | 200/FI, 160/BI | -- | 4 (2×2) FI chips | |
| ACIS-S | 0.5-10 | 8'×48' | -- | -- | -- | 4 FI & 2 BI chips; HETG & METG used simultaneously |
|||||||||
| +HEG | 0.9-10 | -- | -- | 1 FWHM | 45 FWHM | -- | -- | 11+1 | 23+0 | -- | |||||
| +MEG | 0.4-5 | -- | 0.5 FWHM | 2 FWHM | 75 FWHM | -- | 6+11 | 50+3 | 20+0 | -- | |||||
| +LETG | 0.2-9 | -- | 1.5 | 5 | 300 | -- | 10+? | 50+? | 25+? | -- | |||||
| XMM- Newton5 2000- |
MOS6 | 0.2-12 | 30' | 6" | -- | ~50 | 57 | 130 | 3s(1.5ms) | -- | 420 | 850 | 768 | -- | ×2; 7 FI chips; 1.1" pix |
| PN | 0.1-12 | 30' | 6" | ~60 | 67 | 125 | 73ms(7us) | 100 | 1000 | 1227 | 900 | -- | 6×2 BI chips; 4.1" pix | ||
| RGS6 | 0.33-2.5 | ~5' | -- | -- | 0.8 HEW, 1.5 FWHM | 4.0 HEW, 4.5 FWHM | -- | .6s(16ms) per chip | -- | 120+60 | 135+75 | -- | -- | ×2; 1×9 FI chips; splits beam w/MOS | |
| HETE-2 2000- |
SXC | 0.5-10 | 0.91 sr | <30" | 46 | 129 | 1.2 s | 14 | 2 perpendicular 1-D CMs with CCDs | ||||||
| WXM | 2-25 | 1.6 sr | 10' | -- | -- | -- | ~1200 | 1 ms | -- | -- | -- | ~350 | 2 perpendicular 1-D CMs with PSPCs | ||
| FREGATE | 6-400 | 3 sr | -- | -- | -- | 10 us | -- | -- | -- | 120 | NaI detector | ||||
| HETE-2 is a GRB survey instrument, which always points in the anti-solar direction; it also has an optical camera. | |||||||||||||||
| Integral 2002- |
JEM-X | 3-35 | 4.8° | 3' | -- | -- | -- | 1000 | 122 us | -- | -- | -- | 500 | 500 | coded mask |
| Primarily a gamma ray mission; payload includes SPI spectrometer (20keV-8MeV, E/dE ~ 500 @ 1 MeV), IBIS imager (15keV-10MeV, 12' resolution), and OMC optical camera (500-850nm, 5°×5° fov). | |||||||||||||||
| Swift 2004- |
XRT | 0.2-10 | 23.6'×23.6' | 18" HPD | -- | 140 | -- | 30 | 100 | 60 | -- | ||||
| A GRB hunting satellite with rapid autonomous slewing. Payload includes BAT imager (15-150keV, 5240 cm2, 1.4 sr fov, 4' positioning), UVOT (170-650 nm, 17'×17' fov, 0.3" positioning, 6 filters & 2 grisms). | |||||||||||||||
| Suzaku (Astro-E2) 2005- |
R.I.P. |
0.3-12 | 2.9'×2.9' | 2.0' | -- | 7 | 7 | 7 | 100 us | -- | 25 | 150 | 130 | -- | Microcalorimeter; lost cryogen before 1st obs |
| XIS | 0.4-12 (0.2-12 FI) |
18'×18' | 2.0' | -- | ~35 | ~50 | 130 | 8 s | -- | 3×60 FI 150 BI |
3×200 FI 250 BI |
3×220 FI 200 BI |
-- | 4 co-aligned XRTs; 3 w/ FI, 1 w/ BI CCDs | |
| HXD PIN | 10-60 | 34'×34' | non- imaging | ~3000 | 61 us | -- | -- | -- | -- | 230 | 16 columnated units | ||||
| HXD GSO | 30-600 | 4.5°×4.5° | ~10% (sqrt(7.6/EMeV)% FWHM) | 315 cm2 at 100 keV | |||||||||||
| Satellite | Instrument | E band [keV] |
Spatial | Spectral resolution1 [eV] at: | Time resol.2 | Effective area3 [cm2] at: | Notes | ||||||||
| Field of view | Resol. (FWHM) | .1 keV | .5 keV | 1 keV | 6 keV | .1 keV | .5 keV | 1 keV | 6 keV | 20 keV | |||||
| Constellation X 2013? |
RGS | 0.25-2 | >2.5' | 5"-15" HPD | -- | 1 | 4 | -- | -- | ~1400 | ~1500 | -- | -- | grating | |
| XMS | 0.25-10 | 5"-15" HPD | -- | ~2 | ~2 | ~4 | -- | ~8000 | ~15000 | ~6000 | -- | calorimeter | |||
| HXT | 6-≥40 | >8' | 30"-1' HPD | -- | -- | -- | <600 | -- | -- | -- | >~1500 | >~1500 | HXT: multilayer XRT; CdTe or CdZnTe ccd | ||
| XEUS | |||||||||||||||
Abbreviations:
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Additional notes:
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Some more general information:Comparing FI and BI ccd chips. Generally speaking, FI chips offer higher spectral resolution than BI chips, but BI chips offer higher sensitivity, especially at low energies or above ~6 keV. In the case of the XMM-Newton Observatory, the high end of the detector passband is limited by a rapidly declining quantum efficiency (QE) above ~6 keV in the FI chips of XMM-Newton's MOS cameras, whereas the QE of the BI chips in the pn camera is nearly 100% through 10 keV, and has only rolled off to ~70% by 15 keV. Converting between keV and Angstroms. Remember that wavelength (in Angstroms) times energy (in keV) is 12.3984. Converting to/from "Crabs". A convenient unit of
flux density often used in X-ray astronomy is the "Crab".
The Crab nebula has a spectrum equal to: If you ever need to convert flux density into Janskys (who on earth would use such an arcane unit?), a few of useful reference points are: 1 crab ~ 1.088 mJy at 5.0 keV 1 crab ~ 0.237 mJy at 20. keV | |||||||||||||||||||
Information on limiting flux:An instrument generally will only be sensitive to sources of a certain flux or brighter. This is the flux limit. The flux limit can be due to instrument noise, background glow, source confusion, . . . Of course, the flux limit is a function of the integration time of the observation, because the longer you integrate, the more you'll beat down the noise. Only hitting a limit when either there are so many faint sources that you hit the confusion limit, or if there is a truely diffuse background (as opposed to unresolved point sources) then you'll eventually hit a background limit. In the following table, the dominant limiting factor is listed in bold. Specifically, this is the factor which dominates within a reasonable long look for the given instrument. Sure, you could push these limits down by an order of magnitude or so if you stared with the instrument for it's full lifetime, but who'd let you monopolize a satellite like that?
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