| Description: The Soviet orbital observatory GRANAT was launched in December 1989 and was operational till November 1998. One of the main instruments of the observatory was the French-Soviet hard X-ray coded mask telescope SIGMA (Paul et al.1 1991, Adv.Space Res., 11, 279). It was the first space telescope that used coded aperture technique for reconstruction of sky images in hard X-rays (35-1300 keV). The angular resolution of the telescope was approximately 12' and the accuracy of a source localization is approximately 2-3'.<p> SIGMA discovered numerious interesting hard X-ray sources including GRS 1758-258, which is located only 40' from bright soft X-ray source GX 5-1. It detected hard X-ray flux from X-ray burster A1742-294, which is very near to bright black hole binary 1E1740.7-2942. SIGMA set an upper limit on the hard X-ray flux of from the central supermassive black hole in our Galaxy.<p> During the period 1990-1998 SIGMA observed more that one quarter of the sky with sensitivity better than 100 mCrab. The Galact |
| Completely compliant |
| Service URL |
| Input Parameter | Required | Present |
|---|---|---|
| Regular parameters: | ||
| POS | MUST | Yes |
| SIZE | MUST | Yes |
| INTERSECT | MAY | No |
| NAXIS | MAY | Yes |
| CFRAME | MAY | Yes |
| EQUINOX | MAY | Yes |
| CRPIX | MAY | No |
| CRVAL | MAY | No |
| CDELT | MAY | No |
| ROTANG | MAY | No |
| PROJ | MAY | Yes |
| FORMAT | MUST | Yes |
| Service specific parameters | ||
| INTERPOLATION | MAY | Yes |
| big | MAY | Yes |
| small | MAY | Yes |
| Field UCD | Required | Present | Required datatype |
Actual datatype |
|---|---|---|---|---|
| Regular fields: | ||||
| VOX:Image_Title | MUST | Yes | char | char |
| INST_ID | SHOULD | No | char | |
| VOX:Image_MJDateObs | SHOULD | No | double | |
| POS_EQ_RA_MAIN | MUST | Yes | double | double |
| POS_EQ_DEC_MAIN | MUST | Yes | double | double |
| VOX:Image_Naxes | MUST | Yes | int | int |
| VOX:Image_Naxis | MUST | Yes | int | int |
| VOX:Image_Scale | MUST | Yes | double | double |
| VOX:Image_Format | MUST | Yes | char | char |
| VOX:STC_CoordRefFrame | SHOULD | No | char | |
| VOX:STC_CoordEquinox | MAY | No | double | |
| VOX:WCS_CoordProjection | SHOULD | No | char | |
| VOX:WCS_CoordRefPixel | SHOULD | No | double | |
| VOX:WCS_CoordRefValue | SHOULD | No | double | |
| VOX:WCS_CDMatrix | SHOULD | No | double | |
| VOX:BandPass_ID | SHOULD | No | char | |
| VOX:BandPass_Unit | SHOULD | No | char | |
| VOX:BandPass_RefValue | SHOULD | No | double | |
| VOX:BandPass_HiLimit | SHOULD | No | double | |
| VOX:BandPass_LoLimit | SHOULD | No | double | |
| VOX:Image_PixFlags | SHOULD | Yes | char | char |
| VOX:Image_AccessReference | MUST | Yes | char | char |
| Service specific fields: | ||||
| VOX:LogicalName | MAY | YES | char | |