data_model.md

# L1-MBI Data model

## File: \*\_*_L1_1.fits

### File contents

| HDU   | data                    | note        |
|-------|-------------------------|-------------|
| HDU0  | None                    | PrimaryHDU  |
| HDU1  | reduced SCI (9k x 9k)   | ImageHDU    |
| HDU2  | reduced ERR (9k x 9k)   | ImageHDU    |
| HDU3  | reduced DQ (9k x 9k)    | ImageHDU    |
 

### *HDU0 --> HDU1

HDU0 修改 `NEXTEND=3`
模块之间用COMMENT隔开，例如
```
COMMENT ==================================================================      
COMMENT QC0 CHECK                                                               
COMMENT ==================================================================  
```
精简每个关键字的comment
`-`表示不可能失败，不会使用fill value

### HDU1

#### Header of `csst_ms_sls_instrument`

| keyword      | value                    | comment                                      | fill value | type   | last modified |
|--------------|:-------------------------|----------------------------------------------|------------|--------|---------------|
| VER_CRDS     | '0.0.1 '                 | Version of CRDS file selection software used | -          | str    | C7            |
| EXTNAME      | 'SCI'                    | Extension name                               | 'SCI'      | str    | C7            |
| EXTVER       | 1                        | Extension version number                     | 1          | int    | C7            |
| BUNIT        | 'e-/s'                   | Brightness units                             | 'e-/s'     | str    | C7            |
| R_GAIN       | '*.gain.fits'            | Gain reference file name                     | 'N/A'      | str    | C7            |
| R_READN      | '*.rn.fits'              | Read noise reference file name               | 'N/A'      | str    | C7            |
| R_SATURA     | '*.sat.fits'             | Saturation reference file name               | 'N/A'      | str    | C7            |
| R_MASK       | '*.msk.fits'             | Mask reference file name                     | 'N/A'      | str    | C7            |
| R_BIAS       | '*bias.fits'             | SuperBias reference file name                | 'N/A'      | str    | C7            |
| R_DARK       | '*dark.fits'             | Dark reference file name                     | 'N/A'      | str    | C7            |
| R_DFLAT      | '*flat.fits'             | Detector Flat reference file name            | 'N/A'      | str    | C7            |
| STA_DQINI    | 0                        | Data Quality Initialization status           | 1          | int    | C7            |
| STA_SATURA   | 0                        | Saturation Checking status                   | 1          | int    | C7            |
| STA_ERRINI   | 0                        | Error Initialization status                  | 1          | int    | C7            |
| STA_BIAS     | 0                        | Bias correction status                       | 1          | int    | C7            |
| STA_DARK     | 0                        | Dark correction status                       | 1          | int    | C7            |
| STA_FLAT     | 0                        | Flat field correction status                 | 1          | int    | C7            |
| NGOODPIX     | 84794368                 | Number of good pixels                        | -9999      | float  | C7            |
| GOODMAX      | 260.0                    | Maxmum value of good pixels                  | -9999      | float  | C7            |
| GOODMIN      | -0.001                   | Minmum value of good pixels                  | -9999      | float  | C7            |
| GOODMEAN     | 0.3                      | Mean value of good pixels                    | -9999      | float  | C7            |
| SNRMIN       | 187.4                    | Minmum signal to noise of good pixels        | -9999      | float  | C7            |
| SNRMAX       | 1.2                      | Maxmum signal to noise of good pixels        | -9999      | float  | C7            |
| SNRMEAN      | 3.38                     | Average of the dark values subtracted        | -9999      | float  | C7            |
| CRCOUNT      | 88988                    | Cosmic ray counts                            | -9999      | float  | C7            |
| VER_INST     | '0.0.1 '                 | Instrument calibration pipeline version      | -          | str    | C7            |
| STA_INST     | 0                        | Instrument calibration status                | 1          | int    | C7            |
| STM_INST     | '2022-12-30T10:18:53'    | Instrument pipeline processing time          | -          | str    | C7            |
| HISTORY      | '**step complete.'       | Record processing message                    | -          | str    | C7            |

#### Header of `csst_ms_sls_position`

位置定标信息新开一节
CD1_1等系数在修改后挪到这一节

| keyword  | value                 | comment                                  | fill value | type   | module                | last modified |
|----------|:----------------------|------------------------------------------|------------|--------|-----------------------|---------------|
| CTYPE1   | 'RA---TPV'            | type of ra                               | 'RA---TAN' | str    | csst_ms_sls_position  | C7            |
| CTYPE2   | 'DEC--TPV'            | type of dec                              | 'DEC--TAN' | str    | csst_ms_sls_position  | C7            |
| CUNIT1   | 'deg  '               | unit of ra                               | 'deg'      | str    | csst_ms_sls_position  | C7            |
| CUNIT2   | 'deg  '               | unit of dec                              | 'deg'      | str    | csst_ms_sls_position  | C7            |
| RADESYS  | 'ICRS '               | international celestial reference system | -          | str    | csst_ms_sls_position  | C7            |
| PV1_0    | 0.003205383944913964  | pv coefficients                          | -9999      | f32    | csst_ms_sls_position  | C7            |
| PV1_1    | 0.8673020820536499    | pv coefficients                          | -9999      | f32    | csst_ms_sls_position  | C7            |
| PV1_2    | -0.2011989871377834   | pv coefficients                          | -9999      | f32    | csst_ms_sls_position  | C7            |
| PV1_3    | -0.2597214229472611   | pv coefficients                          | -9999      | f32    | csst_ms_sls_position  | C7            |
| PV1_4    | 0.4353828741811097    | pv coefficients                          | -9999      | f32    | csst_ms_sls_position  | C7            |
| PV1_5    | -0.5054216569802673   | pv coefficients                          | -9999      | f32    | csst_ms_sls_position  | C7            |
| PV1_6    | 0.1951474426617432    | pv coefficients                          | -9999      | f32    | csst_ms_sls_position  | C7            |
| PV2_0    | 0.00109803885992697   | pv coefficients                          | -9999      | f32    | csst_ms_sls_position  | C7            |
| PV2_1    | 0.9171065857705857    | pv coefficients                          | -9999      | f32    | csst_ms_sls_position  | C7            |
| PV2_2    | -0.04908256792722099  | pv coefficients                          | -9999      | f32    | csst_ms_sls_position  | C7            |
| PV2_3    | -0.09860562038448289  | pv coefficients                          | -9999      | f32    | csst_ms_sls_position  | C7            |
| PV2_4    | 0.07961855240788976   | pv coefficients                          | -9999      | f32    | csst_ms_sls_position  | C7            |
| PV2_5    | -0.2009224365497067   | pv coefficients                          | -9999      | f32    | csst_ms_sls_position  | C7            |
| PV2_6    | 0.1741954691884874    | pv coefficients                          | -9999      | f32    | csst_ms_sls_position  | C7            |
| NS_POS   | 10                    | number of the stars                      | --         | i8     | csst_ms_sls_position  | C7            |
| RA_OFF   | -0.0                  | mas in unit                              | -9999      | f32    | csst_ms_sls_position  | C7            |
| DEC_OFF  | 0.0                   | mas in unit                              | -9999      | f32    | csst_ms_sls_position  | C7            |
| RA_RMS   | 127.1                 | mas in unit                              | -9999      | f32    | csst_ms_sls_position  | C7            |
| DEC_RMS  | 60.4                  | mas in unit                              | -9999      | f32    | csst_ms_sls_position  | C7            |
| RA_CEN   | 193.299027            | center of detector in ra                 | --         | f32    | csst_ms_sls_position  | C7            |
| DEC_CEN  | 26.08851              | center of detector in dec                | --         | f32    | csst_ms_sls_position  | C7            |
| VER_POS  | '1.0'                 | version of distortion                    | '1.0'      | str    | csst_ms_sls_position  | C7            |
| STM_POS  | '2023-02-16 12:15:16' | time of last modification                | --         | str    | csst_ms_sls_position  | C7            |
| STA_POS  | 0                     | 0 for done, 1 for failure                | 1          | i8     |  csst_ms_sls_position | C7            |


#### Header of `csst_ms_sls_qc1`
| keyword        | value                     | comment                      | fill value | type  | last modified |
|----------------|:--------------------------|------------------------------|------------|-------|---------------|
| STA_QC1        | 0                         | 0 for success, 1 for failure | -1         | i8    | C7            |
| VER_QC1        | '0.0.1'                   | QC1 pipeline version         | '0.0.1'    | str   | C7            |
| FLG_QC1        | 0                         | Quality flags                | -9999      | i16   | C7            |
| STM_QC1        | '2023-02-16T12:15:16'     | QC1 pipeline processing time | -          | str   | C7            | 
 
### HDU2

#### Header of `csst_ms_sls_instrument`

| keyword  | value     | comment                    | fill value | type      | last modified |
|----------|-----------|----------------------------|------------|-----------|---------------|
| XTENSION | 'IMAGE'   | Image extension            | -          | str       | C7            |
| BITPIX   | -32       | Bits per data value        | -          | int       | C7            |                 
| NAXIS    | 2         | Number of array dimensions | -          | int       | C7            |                 
| NAXIS1   | 9216      | Size of the axis           | -          | int       | C7            |                 
| NAXIS2   | 9232      | Size of the axis           | -          | int       | C7            |
| PCOUNT   | 0         | Number of parameters       | -          | int       | C7            |                         
| GCOUNT   | 1         | Number of groups           | -          | int       | C7            |                                       
| EXTNAME  | 'ERR'     | Extension name             | 'ERR'      | str       | C7            |
| EXTVER   | 1         | Extension version number   | 1          | int       | C7            |
| BUNIT    | 'e-/s'    | Brightness units           | 'e-/s'     | str       | C7            |

### HDU3

#### Header of `csst_ms_sls_instrument`

| keyword  | value       | comment                    | fill value     | type     | last modified |
|----------|-------------|----------------------------|----------------|----------|---------------|
| XTENSION | 'IMAGE'     | Image extension            | -              | str      | C7            |
| BITPIX   | 16          | Bits per data value        | -              | int      | C7            |                 
| NAXIS    | 2           | Number of array dimensions | -              | int      | C7            |                 
| NAXIS1   | 9216        | Size of the axis           | -              | int      | C7            |                 
| NAXIS2   | 9232        | Size of the axis           | -              | int      | C7            |
| PCOUNT   | 0           | Number of parameters       | -              | int      | C7            |                         
| GCOUNT   | 1           | Number of groups           | -              | int      | C7            |
| EXTNAME  | 'DQ'        | Extension name             | 'DQ'           | str      | C7            |
| EXTVER   | 1           | Extension version number   | 1              | int      | C7            |
| BUNIT    | 'unitless'  | Brightness units           | 'unitless'     | str      | C7            |