Bias, Parameter Block, & Orbit Ephemeris Files
| Filename | Description | Content | SDP Pipeline |
|---|---|---|---|
| acis_bias0.fits | ACIS bias maps | BIAS0 | ACIS0 |
| acis_pbk0.fits | ACIS parameter block | PBK | ACIS0 |
| orbit_eph1.fits | orbit ephemeris | ORBITEPHEM1 | EPHEM1 |
ACIS Bias Maps
| Filename | Description | Content | SDP Pipeline |
|---|---|---|---|
| acis_bias0.fits | ACIS bias maps | BIAS0 | ACIS0 |
Description:
When the bad pixel list is created, each bias map is searched for pixels whose bias values are either too low or too high. There is one 1024x1024 pixel bias map image for each ACIS chip that was used for the observation.
There are no creator tools; the bias maps are generated internally.
ACIS Parameter Block
| Filename | Description | Content | SDP Pipeline |
|---|---|---|---|
| acis_pbk0.fits | ACIS parameter block | PBK | ACIS0 |
Description:
The parameter block file is needed in conjunction with the bias maps when creating a new bad pixel list. It is used to determine observational parameters, such as which CCDs are active, the READMODE and DATAMODE, etc.
There are no creator tools; the parameter block solution file is generated internally.
Columns:
| Column Name | Units | Description |
|---|---|---|
| CCD_ID | CCD ID | |
| FEP_ID | Front End Processor ID | |
| VIDRESP | CCD video chain response selection, 0 for 1:1 | |
| EVT_THR[4] | adu | Event thresholds for nodes A-D |
| SPL_THR[4] | adu | Split thresholds for output nodes A-D |
| BCMPSLOT | Slot identifier for bias map compression tab | |
| BIASALG | Bias algorithm is. 1:whole frame; 2:strip | |
| BIASARG0 | Bias arguement 0 | |
| BIASARG1 | Bias arguement 1 | |
| BIASARG2 | Bias arguement 2 | |
| BIASARG3 | Bias arguement 3 | |
| BIASARG4 | Bias arguement 4 | |
| VID_OFF[4] | Video offsets for CCD output nodes A-D |
Orbit Ephemeris
| Filename | Description | Content | SDP Pipeline |
|---|---|---|---|
| orbit_eph1.fits | orbit ephemeris | ORBITEPHEM1 | EPHEM1 |
Description:
The definitive orbit ephemeris information for the observation. The coordinates are recorded as Earth-centered Cartesian ICRS coordinates.
There are no creator tools; the orbit ephemeris file is generated internally.
Columns:
| Column Name | Units | Description |
|---|---|---|
| Time | s | Time |
| X | m | X coordinate |
| Y | m | Y coordinate |
| Z | m | Z coordinate |
| Vx | m/s | Velocity in the X direction |
| Vy | m/s | Velocity in the Y direction |
| Vz | m/s | Velocity in the Z direction |
