PRObabilistic Value-Added Bright Galaxy Survey (PROVABGS) Catalog¶
Overview¶
The PRObabilistic Value-Added Bright Galaxy Survey (PROVABGS) catalog includes physical properties of galaxies inferred jointly from Legacy Surveys photometry and DESI spectroscopy. The physical parameters are inferred using a full Bayesian inference framework and state-of-the-art Spectral Energy Distribution (SED) modeling. For details on the inference framework, SED modeling, and the neural emulators used to accelerate the inferance, we refer readers to Hahn et al. (2023) and Kwon et al. (2023).
Data Access¶
Data URL: https://data.desi.lbl.gov/public/edr/vac/edr/provabgs/v1.0/
NERSC access:
/global/cfs/cdirs/desi/public/edr/vac/edr/provabgs/v1.0/
Documentation¶
The PROVABGS analysis pipeline is publicly available on GitHub.
Files¶
BGS_ANY_full.provabgs.sv3.v0.hdf5: PROVABGS catalog for all BGS galaxies in the DESI One-Percent Survey (SV3)
Data model¶
| Column Name | Data Type | Description |
|---|---|---|
| TARGETID | int | Unique 64-bit identifier for each object observed by DESI |
| RA | float64 | Right Ascension in decimal degrees (J2000) |
| DEC | float64 | Declination in decimal degrees (J2000) |
| Z_HP | float64 | Redrock redshift |
| ZERR | float64 | Redrock redshift error |
| TSNR2_BGS | float32 | Signal-to-noise metric for observed spectra |
| MAG_G | float64 | Extinction corrected g-band magnitude |
| MAG_R | float64 | Extinction corrected r-band magnitude |
| MAG_Z | float64 | Extinction corrected z-band magnitude |
| MAG_W1 | float64 | Extinction corrected W1-band magnitude |
| FIBMAG_R | float64 | Extinction corrected r-band fiber aperture magnitude |
| SCHLEGEL_COLOR | float64 | (z - W1) - 1.2\(\times\)(g - r) + 1.2 color used for BGS Faint selection |
| HPIX_64 | int | HEALPixel of target |
| PROVABGS_MCMC | float64 | [Nx100x13] array of 100 samples drawn from the 13-dimensional PROVABGS posterior. The 13 parameters correspond to log(M_form), beta_1, beta_2, beta_3, beta_4, f_burst, t_burst, gamma_1, gamma_2, tau_BC, tau_ISM, n_dust, f_fiber. Note that log(M_form) is different than log(stellar mass). |
| provabgs_theta_bf | float64 | [Nx13] array of best-fit PROVABGS parameters |
| provabgs_z_max | float64 | Maximum redshift in which the galaxy could have been observed |
| provabgs_logMstar_bf | float64 | Best-fit log(stellar mass) |
| provabgs_logMstar | float64 | 100 samples of the log stellar mass posterior |
| provabgs_w_zfail | float64 | Redshift-failure weights derived from TSNR2_BGS and FIBMAG_R |
| provabgs_w_fibassign | float64 | Fiber assignment weight derived from random fiber assignment runs |
| is_bgs_bright | bool | True if in BGS Bright |
| is_bgs_faint | bool | True if in BGS Faint |
Contact¶
For problems, questions, or general help, please contact ChangHoon Hahn.