Broad Absorption Line (BAL) Quasar Catalog¶
Overview¶
The BAL value-added catalogs contain updated redshifts for the DESI Early Data Release (EDR). A more detailed explanation of the catalogs can be found in Filbert et al. (in preparation).
Data Access¶
Data URL: https://data.desi.lbl.gov/public/edr/vac/edr/bal/fuji/v1.0/
NERSC access for DESI collaborators:
/global/cfs/cdirs/desi/public/edr/vac/edr/bal/fuji/v1.0/
Documentation¶
The VAC files contain catalogs of BALs that have had their absorption features masked. The BALs were then run through Paul Martini’s baltools to create the catalogs.
Our VAC file contains two catalogs which are described in more detail in the table below. The relevant data model for these catalogs can be found in Table 1 of Filbert et. al (2023) (in preperation).
| File Name | File Size | Number of QSOs |
|---|---|---|
| QSO_cat_fuji_sv1_dark-bal-mask-priors-SNR-v1.0.fits | 42.7 MB | 37,903 |
| QSO_cat_fuji_sv3_dark-bal-mask-priors-SNR-v1.0.fits | 57.4 MB | 50,993 |
The following table contains descriptions of some of the columns in our catalogs. Links to descriptions of the additional columns are provided below.
| Column Name | # | Description |
|---|---|---|
| TARGETID | 0 | Link |
| Z | 1 | Best-fit redshift after masking |
| ZERR | 2 | Best-fit redshift error after masking |
| ZWARN | 3 | Warning flags (0 is good) |
| SPECTYPE | 4 | Spectype from Redrock file |
| COADD_FIBERSTATUS | 5 | Bitwise-AND of input FIBERSTATUS |
| TARGET_RA | 6 | Target Right Ascension (decimal degrees) |
| TARGET_DEC | 7 | Target Declination (decimal degrees) |
| MORPHTYPE | 8 | Link |
| EBV | 9 | Link |
| PROBA_RF | 25 | Probability of Random Forest selection |
| MASKBITS | 26 | Link |
| SV3_DESI_TARGET | 27 | DESI (dark time program) target selection bitmask for SV3 |
| SV3_SCND_TARGET | 28 | Secondary target selection bitmask for SV3 |
| DESI_TARGET | 29 | Link |
| COADD_NUMEXP | 30 | Number of exposures in coadd |
| COADD_EXPTIME | 31 | Summed exposure time for coadd (seconds) |
| COADD_EXPTIME | 32 | Target selection bitmask for commissioning |
| SV1_DESI_TARGET | 33 | DESI (dark time program) target selection bitmask for SV1 |
| SV2_DESI_TARGET | 34 | DESI (dark time program) target selection bitmask for SV2 |
| SV1_SCND_TARGET | 35 | Secondary target selection bitmask for SV1 |
| SV2_SCND_TARGET | 36 | Secondary target selection bitmask for SV2 |
| SCND_TARGET | 37 | Link |
| TSNR2_LYA | 38 | LYA template (S/N)^2 summed over B, R, Z |
| TSNR2_QSO | 39 | QSO template (S/N)^2 summed over B, R, Z |
| QSO_MASKBITS | 61 | QSO selection bitmask |
| HPXPIXEL | 62 | Link |
| SURVEY | 63 | SV3 |
| PROGRAM | 64 | Program name (dark) |
The descriptions for columns 10 through 24 can be found here.
The descriptions for columns 40 through 46 can be found here.
The descriptions for columns 47 through 60 can be found here.
The descriptions for columns 65 through 96, as well as column 103, can be found in Table 1 of Filbert et al. (in preparation).
Note: Columns 97 through 102 are redundant columns.
Contact¶
Contact Simon Filbert or Paul Martini for questions regarding these catalogs.