J/A+A/708/A289  LEGA-C stellar population scaling relation. I. (Gallazzi+, 2026)

LEGA-C stellar population scaling relations. I. Chemo-archaeological doownsizing trends at z∼0.7. Gallazzi A.R., Zibetti S., van der Wel A., Nersesian A., Kaushal Y., Bezanson R., D'Eugenio F., Bell E.F., Leja J., Scholz-Diaz L., Wu P.-F., Pacifici C., Maseda M., Mattolini D. <Astron. Astrophys. 708, A289 (2026)> =2026A&A...708A.289G 2026A&A...708A.289G (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, spectra ; Stars, ages ; Abundances ; Galaxy catalogs ; Surveys Keywords: galaxies: abundances - galaxies: evolution - galaxies: fundamental parameters - galaxies: high-redshift - galaxies: stellar content Abstract: We analysed the stellar population properties of a well-defined sample of 552 galaxies at redshift 0.6<z<0.77 drawn from the LEGA-C spectroscopic survey. This paper is the first of a series, and it is aimed at i) presenting the catalogue of revised absorption indices for LEGA-C DR3 and of the inferred physical parameter estimates while describing their systematic uncertainties and at ii) deriving benchmark scaling relations for the general massive galaxy population at intermediate redshift. We estimated light-weighted mean ages and stellar metallicities through careful analysis of key absorption features in the stellar continuum spectra of the galaxies coupled with photometry. The observables were interpreted in a Bayesian framework with a comprehensive library of model spectra based on stochastic star formation histories, chemical enrichment histories, and dust attenuations. We discuss various sources of systematic uncertainties within our method as well as systematic differences with results from other spectral fitting approaches. We derived volume-weighted scaling relations connecting light-weighted mean ages and stellar metallicities with galaxy stellar mass for the general galaxy population at =0.7 and masses >1010M. We find the downsizing trends observed in the local Universe to be already in place 6Gyr ago. We also observe a bimodal distribution of light-weighted ages as a function of mass, transitioning around 1011M. Such a bimodality is not observed in the stellar metallicity-mass relation, which changes from a steep to a flat regime across Mstar∼1010.8M. Similar trends in age and metallicity also emerge as a function of velocity dispersion, but with a sharper transition from young to old around log(sigmastar)=2.3. Differences with respect to the trends as a function of stellar mass suggest that age is primarily dependent on velocity dispersion below and above the transition regime, while both the stellar mass and the depth of the total gravitational potential well (as traced by the velocity dispersion) contribute to stellar metallicity. We release the catalogues of revised absorption index measurements for LEGA-C DR3 used in this work and of the inferred stellar population physical parameters to public repositories. Description: We provide three catalogs matched to the LEGA-C DR3 general catalog, containing measurements of the absorption indices on the emission-line subtracted LEGA-C spectra and estimates of stellar population physical parameters. For the absorption indices we provide two catalogs: one that contains index measurements performed on the individual emission-line subtracted spectra; one that contains index measurements obtained by combining duplicate observations when available. A separate catalog provides estimates of stellar population physical parameters as derived with BaStA using duplicate-combined index measurements (this paper), with Prospector (Nersesian et al., 2025A&A...695A..86N 2025A&A...695A..86N) and Bagpipes (Kaushal et al., 2024ApJ...961..118K 2024ApJ...961..118K) both using the original individual spectra, combined with photometric information. Physical parameters include stellar mass, light- and mass-weighted ages, light- and mass-weighted stellar metallicities, dust attenuation. Additionally, we provide flags for sample selections and completeness weights as in Gallazzi et al. (Paper I and II, 2026A&A...708A.290G 2026A&A...708A.290G) and SFR estimates. File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file absidx.dat 1962 4081 *Absorption indices measured on individual emission-line subtracted LEGA-C spectra (corrected version, 16-Apr-2026) absidx_d.dat 2019 4081 *Absorption indices measurements obtained by combining measurements from duplicate observations when available (corrected version, 16-Apr-2026) stelpop.dat 1486 4081 *Estimates of stellar population physical parameters (light- and mass-weighted age and stellar metallicity, stellar mass, dust attenuation) and flags for sample selection parms.dat 102 10 Median trends of light-weighted age and stellar metallicity as a function of stellar mass for galaxies in the silver sample weighted for volume and completeness (upper part of Table 3) parmg.dat 101 9 Median trends of light-weighted age and stellar metallicity as a function of stellar mass for galaxies in the golden sample (lower part of Table 3) parss.dat 100 8 Median trends of light-weighted age and stellar metallicity as a function of stellar velocity dispersion for galaxies in the silver sample weighted for volume and completeness (upper part of Table 5) parsg.dat 100 8 Median trends of light-weighted age and stellar metallicity as a function of stellar velocity dispersion for galaxies in the golden sample (lower part of Table 5) -------------------------------------------------------------------------------- Note on absidx.dat: as described in van der Wel et al., 2021ApJS..256...44V 2021ApJS..256...44V, and the paper. Note on absidx_d.dat: as described in the paper. For galaxies without duplicate observations the values in absidx.dat and in absidx_d.dat are the same. Note on stelpop.dat: as obtained with BaStA in the paper. The catalog also includes estimates of age, metallicity, mass and dust attenuation from Prospector (Nersesian et al., 2025A&A...695A..86N 2025A&A...695A..86N) and Bagpipes (Kaushal et al., 2024ApJ...961..118K 2024ApJ...961..118K). -------------------------------------------------------------------------------- See also: J/ApJS/256/44 : LEGA-C DR3 catalog (van der Wel+, 2021) J/A+A/703/A5 : Local galaxies scaling relations (Mattolini+, 2025) J/ApJ/961/118 : Census of SFH of galaxies from LEGA-C DR3 (Kaushal+, 2024) J/A+A/708/A290 : LEGA-C stellar population scaling relation. II. (Gallazzi+, 2026) Byte-by-byte Description of file: absidx.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 7- 10 I4 --- LEGACID [1/4081] LEGA-C running sequence number (ID of a unique spectrum as in LEGA-C DR3 catalog) (LEGACID) 14- 28 E15.6 mag Lick-CN1 ?=- Lick CN1 absorption index value in mag (LICK_CN1) (G1) 32- 46 E15.6 mag e_Lick-CN1 []?=- Error on Lick CN1 index (LICKCN1ERR) (G2) 50- 53 I4 --- f_Lick-CN1 Warning flag for index measurement (LICKCN1FLAG) (G3) 57- 71 E15.6 --- Lick-CN1-RP ?=- Resolving power of Lick CN1 index (LICKCN1RP) (G4) 75- 89 E15.6 mag Lick-CN2 ?=- Lick CN2 absorption index value in mag (LICK_CN2) (G1) 93- 107 E15.6 mag e_Lick-CN2 []?=- Error on Lick CN2 index (LICKCN2ERR) (G2) 111- 114 I4 --- f_Lick-CN2 Warning flag for index measurement (LICKCN2FLAG) (G3) 118- 132 E15.6 --- Lick-CN2-RP ?=- Resolving power of Lick CN2 index (LICKCN2RP) (G4) 136- 150 E15.6 0.1nm Lick-Ca4227 ?=- Lick Ca4227 absorption index value in Å (LICK_CA4227) (G1) 154- 168 E15.6 0.1nm e_Lick-Ca4227 []?=- Error on Lick Ca4227 index (LICKCA4227ERR) (G2) 172- 175 I4 --- f_Lick-Ca4227 Warning flag for index measurement (LICKCA4227FLAG) (G3) 179- 193 E15.6 --- Lick-Ca4227-RP ?=- Resolving power of Lick Ca4227 index (LICKCA4227RP) (G4) 197- 211 E15.6 0.1nm Lick-G4300 ?=- Lick G4300 absorption index value in Å (LICK_G4300) (G1) 215- 229 E15.6 0.1nm e_Lick-G4300 []?=- Error on Lick G4300 index (LICKG4300ERR) (G2) 233- 236 I4 --- f_Lick-G4300 Warning flag for index measurement (LICKG4300FLAG) (G3) 240- 254 E15.6 --- Lick-G4300-RP ?=- Resolving power of Lick G4300 index (LICKG4300RP) (G4) 258- 272 E15.6 0.1nm Lick-Fe4383 ?=- Lick Fe4383 absorption index value in Å (LICK_FE4383) (G1) 276- 290 E15.6 0.1nm e_Lick-Fe4383 []?=- Error on Lick Fe4383 index (LICKFE4383ERR) (G2) 294- 297 I4 --- f_Lick-Fe4383 Warning flag for index measurement (LICKFE4383FLAG) (G3) 301- 315 E15.6 --- Lick-Fe4383-RP ?=- Resolving power of Lick Fe4383 index (LICKFE4383RP) (G4) 319- 333 E15.6 0.1nm Lick-Ca4455 ?=- Lick Ca4455 absorption index value in Å (LICK_CA4455) (G1) 337- 351 E15.6 0.1nm e_Lick-Ca4455 []?=- Error on Lick Ca4455 index (LICKCA4455ERR) (G2) 355- 358 I4 --- f_Lick-Ca4455 Warning flag for index measurement (LICKCA4455FLAG) (G3) 362- 376 E15.6 --- Lick-Ca4455-RP ?=- Resolving power of Lick Ca4455 index (LICKCA4455RP) (G4) 380- 394 E15.6 0.1nm Lick-Fe4531 ?=- Lick Fe4531 absorption index value in Å (LICK_FE4531) (G1) 398- 412 E15.6 0.1nm e_Lick-Fe4531 []?=- Error on Lick Fe4531 index (LICKFE4531ERR) (G2) 416- 419 I4 --- f_Lick-Fe4531 Warning flag for index measurement (LICKFE4531FLAG) (G3) 423- 437 E15.6 --- Lick-Fe4531-RP ?=- Resolving power of Lick Fe4531 index (LICKFE4531RP) (G4) 441- 455 E15.6 0.1nm Lick-C4668 ?=- Lick C4668 absorption index value in Å (LICK_C4668) (G1) 459- 473 E15.6 0.1nm e_Lick-C4668 []?=- Error on Lick C4668 index (LICKC4668ERR) (G2) 477- 480 I4 --- f_Lick-C4668 Warning flag for index measurement (LICKC4668FLAG) (G3) 484- 498 E15.6 --- Lick-C4668-RP ?=- Resolving power of Lick C4668 index (LICKC4668RP) (G4) 502- 516 E15.6 0.1nm Lick-Hb ?=- Lick Hbeta absorption index value in Å (LICK_HB) (G1) 520- 534 E15.6 0.1nm e_Lick-Hb []?=- Error on Lick Hbeta index (LICKHBERR) (G2) 538- 541 I4 --- f_Lick-Hb Warning flag for index measurement (LICKHBFLAG) (G3) 545- 559 E15.6 --- Lick-Hb-RP ?=- Resolving power of Lick Hbeta index (LICKHBRP) (G4) 563- 577 E15.6 0.1nm Lick-Fe5015 ?=- Lick Fe5015 absorption index value in Å (LICK_FE5015) (G1) 581- 595 E15.6 0.1nm e_Lick-Fe5015 []?=- Error on Lick Fe5015 index (LICKFE5015ERR) (G2) 599- 602 I4 --- f_Lick-Fe5015 Warning flag for index measurement (LICKFE5015FLAG) (G3) 606- 620 E15.6 --- Lick-Fe5015-RP ?=- Resolving power of Lick Fe5015 index (LICKFE5015RP) (G4) 624- 638 E15.6 mag Lick-Mg1 ?=- Lick Mg1 absorption index value in mag (LICK_MG1) (G1) 642- 656 E15.6 mag e_Lick-Mg1 []?=- Error on Lick Mg1 index (LICKMG1ERR) (G2) 660- 663 I4 --- f_Lick-Mg1 Warning flag for index measurement (LICKMG1FLAG) (G3) 667- 681 E15.6 --- Lick-Mg1-RP ?=- Resolving power of Lick Mg1 index (LICKMG1RP) (G4) 685- 699 E15.6 mag Lick-Mg2 ?=- Lick Mg2 absorption index value in mag (LICK_MG2) (G1) 703- 717 E15.6 mag e_Lick-Mg2 []?=- Error on Lick Mg2 index (LICKMG2ERR) (G2) 721- 724 I4 --- f_Lick-Mg2 Warning flag for index measurement (LICKMG2FLAG) (G3) 728- 742 E15.6 --- Lick-Mg2-RP ?=- Resolving power of Lick Mg2 index (LICKMG2RP) (G4) 746- 760 E15.6 0.1nm Lick-Mgb ?=- Lick Mgb absorption index value in Å (LICK_MGB) (G1) 764- 778 E15.6 0.1nm e_Lick-Mgb []?=- Error on Lick Mgb index (LICKMGBERR) (G2) 782- 785 I4 --- f_Lick-Mgb Warning flag for index measurement (LICKMGBFLAG) (G3) 789- 803 E15.6 --- Lick-Mgb-RP ?=- Resolving power of Lick Mgb index (LICKMGBRP) (G4) 807- 821 E15.6 0.1nm Lick-Fe5270 ?=- Lick Fe5270 absorption index value in Å (LICK_FE5270) (G1) 825- 839 E15.6 0.1nm e_Lick-Fe5270 []?=- Error on Lick Fe5270 index (LICKFE5270ERR) (G2) 843- 846 I4 --- f_Lick-Fe5270 Warning flag for index measurement (LICKFE5270FLAG) (G3) 850- 864 E15.6 --- Lick-Fe5270-RP ?=- Resolving power of Lick Fe5270 index (LICKFE5270RP) (G4) 868- 882 E15.6 0.1nm Lick-Fe5335 ?=- Lick Fe5335 absorption index value in Å (LICK_FE5335) (G1) 886- 900 E15.6 0.1nm e_Lick-Fe5335 []?=- Error on Lick Fe5335 index (LICKFE5335ERR) (G2) 904- 907 I4 --- f_Lick-Fe5335 Warning flag for index measurement (LICKFE5335FLAG) (G3) 911- 925 E15.6 --- Lick-Fe5335-RP ?=- Resolving power of Lick Fe5335 index (LICKFE5335RP) (G4) 929- 943 E15.6 0.1nm Lick-Fe5406 ?=- Lick Fe5406 absorption index value in Å (LICK_FE5406) (G1) 947- 961 E15.6 0.1nm e_Lick-Fe5406 []?=- Error on Lick Fe5406 index (LICKFE5406ERR) (G2) 965- 968 I4 --- f_Lick-Fe5406 ?=- Warning flag for index 972- 986 E15.6 --- Lick-Fe5406-RP ?=- Resolving power of Lick Fe5406 index (LICKFE5406RP) (G4) 990-1004 E15.6 0.1nm Lick-Fe5709 ?=- Lick Fe5709 absorption index value in Å (LICK_FE5709) (G1) 1008-1022 E15.6 0.1nm e_Lick-Fe5709 []?=- Error on Lick Fe5709 index (LICKFE5709ERR) (G2) 1026-1029 I4 --- f_Lick-Fe5709 Warning flag for index measurement (LICKFE5709FLAG) (G3) 1033-1047 E15.6 --- Lick-Fe5709-RP ?=- Resolving power of Lick Fe5709 index (LICKFE5709RP) (G4) 1051-1065 E15.6 0.1nm Lick-Fe5782 ?=- Lick Fe5782 absorption index value in Å (LICK_FE5782) (G1) 1069-1083 E15.6 0.1nm e_Lick-Fe5782 []?=- Error on Lick Fe5782 index (LICKFE5782ERR) (G2) 1087-1090 I4 --- f_Lick-Fe5782 Warning flag for index measurement (LICKFE5782FLAG) (G3) 1094-1108 E15.6 --- Lick-Fe5782-RP ?=- Resolving power of Lick Fe5782 index (LICKFE5782RP) (G4) 1112-1126 E15.6 0.1nm Lick-NaD ?=- Lick NaD absorption index value in Å (LICK_NAD) (G1) 1130-1144 E15.6 0.1nm e_Lick-NaD []?=- Error on Lick NaD index (LICKNADERR) (G2) 1148-1151 I4 --- f_Lick-NaD Warning flag for index measurement (LICKNADFLAG) (G3) 1155-1169 E15.6 --- Lick-NaD-RP ?=- Resolving power of Lick NaD index (LICKNADRP) (G4) 1173-1187 E15.6 mag Lick-TiO1 ?=- Lick TiO1 absorption index value in mag (LICK_TIO1) (G1) 1191-1205 E15.6 mag e_Lick-TiO1 []?=- Error on Lick TiO1 index (LICKTIO1ERR) (G2) 1209-1212 I4 --- f_Lick-TiO1 Warning flag for index measurement (LICKTIO1FLAG) (G3) 1216-1230 E15.6 --- Lick-TiO1-RP ?=- Resolving power of Lick TiO1 index (LICKTIO1RP) (G4) 1234-1248 E15.6 mag Lick-TiO2 ?=- Lick TiO2 absorption index value in mag (LICK_TIO2) (G1) 1252-1266 E15.6 mag e_Lick-TiO2 []?=- Error on Lick TiO2 index (LICKTIO2ERR) (G2) 1270-1273 I4 --- f_Lick-TiO2 Warning flag for index measurement (LICKTIO2FLAG) (G3) 1277-1291 E15.6 --- Lick-TiO2-RP ?=- Resolving power of Lick TiO2 index (LICKTIO2RP) (G4) 1295-1309 E15.6 0.1nm Lick-HdA ?=- Lick Hdelta_A absorption index value in Å (LICKHDA) (G1) 1313-1327 E15.6 0.1nm e_Lick-HdA []?=- Error on Lick Hdelta_A index (LICKHDA_ERR) (G2) 1331-1334 I4 --- f_Lick-HdA Warning flag for index measurement (LICKHDA_FLAG) (G3) 1338-1352 E15.6 --- Lick-HdA-RP ?=- Resolving power of Lick Hdelta_A index (LICKHDA_RP) (G4) 1356-1370 E15.6 0.1nm Lick-HgA ?=- Lick Hgamma_A absorption index value in Å (LICKHGA) (G1) 1374-1388 E15.6 0.1nm e_Lick-HgA []?=- Error on Lick Hgamma_A index (LICKHGA_ERR) (G2) 1392-1395 I4 --- f_Lick-HgA Warning flag for index measurement (LICKHGA_FLAG) (G3) 1399-1413 E15.6 --- Lick-HgA-RP ?=- Resolving power of Lick Hgamma_A index (LICKHGA_RP) (G4) 1417-1431 E15.6 0.1nm Lick-HdF ?=- Lick Hdelta_F absorption index value in Å (LICKHDF) (G1) 1435-1449 E15.6 0.1nm e_Lick-HdF []?=- Error on Lick Hdelta_F index (LICKHDF_ERR) (G2) 1453-1456 I4 --- f_Lick-HdF Warning flag for index measurement (LICKHDF_FLAG) (G3) 1460-1474 E15.6 --- Lick-HdF-RP ?=- Resolving power of Lick Hdelta_F index (LICKHDF_RP) (G4) 1478-1492 E15.6 0.1nm Lick-HgF ?=- Lick Hgamma_F absorption index value in Å (LICKHGF) (G1) 1496-1510 E15.6 0.1nm e_Lick-HgF []?=- Error on Lick Hgamma_F index (LICKHGF_ERR) (G2) 1514-1517 I4 --- f_Lick-HgF Warning flag for index measurement (LICKHGF_FLAG) (G3) 1521-1535 E15.6 --- Lick-HgF-RP ?=- Resolving power of Lick Hgamma_F index (LICKHGF_RP) (G4) 1539-1553 E15.6 --- D4000N ?=- D4000n index value (D4000_N) (G1) 1557-1571 E15.6 --- e_D4000N []?=- Error on D4000n index (D4000NERR) (G2) 1575-1578 I4 --- f_D4000N Warning flag for index measurement (D4000NFLAG) (G3) 1582-1596 E15.6 --- D4000N-RP ?=- Resolving power of D4000n index (D4000NRP) (G4) 1600-1614 E15.6 0.1nm HdHg ?=- Composite HdeltaA+HgammaA absorption index value in Å (HDHG) (G1) 1618-1632 E15.6 0.1nm e_HdHg []?=- Error on HdeltaA+HgammaA index (HDHG_ERR) (G2) 1636-1639 I4 --- f_HdHg Warning flag for index measurement (HDHG_FLAG) (G3) 1643-1657 E15.6 --- HdHg-RP ?=- Resolving power of HdeltaA+HgammaA index (HDHG_RP) (G4) 1661-1675 E15.6 mag Mg2Fe ?=- Composite [Mg2Fe] absorption index value in mag (MG2FE) (G1) 1679-1693 E15.6 mag e_Mg2Fe []?=- Error on [Mg2Fe] index (MG2FE_ERR) (G2) 1697-1700 I4 --- f_Mg2Fe Warning flag for index measurement (MG2FE_FLAG) (G3) 1704-1718 E15.6 --- Mg2Fe-RP ?=- Resolving power of [Mg2Fe] index (MG2FE_RP) (G4) 1722-1736 E15.6 0.1nm MgFep ?=- Composite [MgFe]' absorption index value in Å (MGFE_PRIME) (G1) 1740-1754 E15.6 0.1nm e_MgFep []?=- Error on [MgFe]' index (MGFEPRIMEERR) (G2) 1758-1761 I4 --- f_MgFep Warning flag for index measurement (MGFEPRIMEFLAG) (G3) 1765-1779 E15.6 --- MgFep-RP ?=- Resolving power of [MgFe]' index (MGFEPRIMERP) (G4) 1783-1797 E15.6 0.1nm Mg/Fe ?=- Mgb/<Fe> absorption index value in Å (MG_FE) (G1) 1801-1815 E15.6 0.1nm e_Mg/Fe []?=- Error on Mgb/<Fe> index (MGFEERR) (G2) 1819-1822 I4 --- f_Mg/Fe Warning flag for index measurement (MGFEFLAG) (G3) 1826-1840 E15.6 --- Mg/Fe-RP ?=- Resolving power of Mgb/<Fe> index (MGFERP) (G4) 1844-1858 E15.6 0.1nm MgFe50p ?=- [MgFe50]' absorption index value in Å (MGFE50_PRIME) (G1) 1862-1876 E15.6 0.1nm e_MgFe50p []?=- Error on [MgFe50]' index (MGFE50PRIMEERR) (G2) 1880-1883 I4 --- f_MgFe50p Warning flag for index measurement (MGFE50PRIMEFLAG) (G3) 1887-1901 E15.6 --- MgFe50p-RP ?=- Resolving power of [MgFe50]' index (MGFE50PRIMERP) (G4) 1905-1919 E15.6 0.1nm MgFe52p ?=- [MgFe52]' absorption index value in Å (MGFE52_PRIME) (G1) 1923-1937 E15.6 0.1nm e_MgFe52p []?=- Error on [MgFe52]' index (MGFE52PRIMEERR) (G2) 1941-1944 I4 --- f_MgFe52p Warning flag for index measurement (MGFE52PRIMEFLAG) (G3) 1948-1962 E15.6 --- MgFe52p-RP ?=- Resolving power of [MgFe52]' index (MGFE52PRIMERP) (G4) -------------------------------------------------------------------------------- Byte-by-byte Description of file: absidx_d.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 7- 10 I4 --- LEGACID [1/4081] LEGA-C running sequence number (ID of a unique spectrum as in LEGA-C DR3 catalog) (LEGACID) 14- 28 E15.6 mag Lick-CN1 ?=- Lick CN1 absorption index value in mag (LICK_CN1) (G1) 32- 46 E15.6 mag e_Lick-CN1 []?=- Error on Lick CN1 index (LICKCN1ERR) (G2) 50- 53 I4 --- f_Lick-CN1 Warning flag for index measurement (LICKCN1FLAG) (G3) 57- 71 E15.6 --- Lick-CN1-RP ?=- Resolving power of Lick CN1 index (LICKCN1RP) (G4) 75- 89 E15.6 mag Lick-CN2 ?=- Lick CN2 absorption index value in mag (LICK_CN2) (G1) 93- 107 E15.6 mag e_Lick-CN2 []?=- Error on Lick CN2 index (LICKCN2ERR) (G2) 111- 114 I4 --- f_Lick-CN2 Warning flag for index measurement (LICKCN2FLAG) (G3) 118- 132 E15.6 --- Lick-CN2-RP ?=- Resolving power of Lick CN2 index (LICKCN2RP) (G4) 136- 150 E15.6 0.1nm Lick-Ca4227 ?=- Lick Ca4227 absorption index value in Å (LICK_CA4227) (G1) 154- 168 E15.6 0.1nm e_Lick-Ca4227 []?=- Error on Lick Ca4227 index (LICKCA4227ERR) (G2) 172- 175 I4 --- f_Lick-Ca4227 Warning flag for index measurement (LICKCA4227FLAG) (G3) 179- 193 E15.6 --- Lick-Ca4227-RP ?=- Resolving power of Lick Ca4227 index (LICKCA4227RP) (G4) 197- 211 E15.6 0.1nm Lick-G4300 ?=- Lick G4300 absorption index value in Å (LICK_G4300) (G1) 215- 229 E15.6 0.1nm e_Lick-G4300 []?=- Error on Lick G4300 index (LICKG4300ERR) (G2) 233- 236 I4 --- f_Lick-G4300 Warning flag for index measurement (LICKG4300FLAG) (G3) 240- 254 E15.6 --- Lick-G4300-RP ?=- Resolving power of Lick G4300 index (LICKG4300RP) (G4) 258- 272 E15.6 0.1nm Lick-Fe4383 ?=- Lick Fe4383 absorption index value in Å (LICK_FE4383) (G1) 276- 290 E15.6 0.1nm e_Lick-Fe4383 []?=- Error on Lick Fe4383 index (LICKFE4383ERR) (G2) 294- 297 I4 --- f_Lick-Fe4383 Warning flag for index measurement (LICKFE4383FLAG) (G3) 301- 315 E15.6 --- Lick-Fe4383-RP ?=- Resolving power of Lick Fe4383 index (LICKFE4383RP) (G4) 319- 333 E15.6 0.1nm Lick-Ca4455 ?=- Lick Ca4455 absorption index value in Å (LICK_CA4455) (G1) 337- 351 E15.6 0.1nm e_Lick-Ca4455 []?=- Error on Lick Ca4455 index (LICKCA4455ERR) (G2) 355- 358 I4 --- f_Lick-Ca4455 Warning flag for index measurement (LICKCA4455FLAG) (G3) 362- 376 E15.6 --- Lick-Ca4455-RP ?=- Resolving power of Lick Ca4455 index (LICKCA4455RP) (G4) 380- 394 E15.6 0.1nm Lick-Fe4531 ?=- Lick Fe4531 absorption index value in Å (LICK_FE4531) (G1) 398- 412 E15.6 0.1nm e_Lick-Fe4531 []?=- Error on Lick Fe4531 index (LICKFE4531ERR) (G2) 416- 419 I4 --- f_Lick-Fe4531 Warning flag for index measurement (LICKFE4531FLAG) (G3) 423- 437 E15.6 --- Lick-Fe4531-RP ?=- Resolving power of Lick Fe4531 index (LICKFE4531RP) (G4) 441- 455 E15.6 0.1nm Lick-C4668 ?=- Lick C4668 absorption index value in Å (LICK_C4668) (G1) 459- 473 E15.6 0.1nm e_Lick-C4668 []?=- Error on Lick C4668 index (LICKC4668ERR) (G2) 477- 480 I4 --- f_Lick-C4668 Warning flag for index measurement (LICKC4668FLAG) (G3) 484- 498 E15.6 --- Lick-C4668-RP ?=- Resolving power of Lick C4668 index (LICKC4668RP) (G4) 502- 516 E15.6 0.1nm Lick-Hb ?=- Lick Hbeta absorption index value in Å (LICK_HB) (G1) 520- 534 E15.6 0.1nm e_Lick-Hb []?=- Error on Lick Hbeta index (LICKHBERR) (G2) 538- 541 I4 --- f_Lick-Hb Warning flag for index measurement (LICKHBFLAG) (G3) 545- 559 E15.6 --- Lick-Hb-RP ?=- Resolving power of Lick Hbeta index (LICKHBRP) (G4) 563- 577 E15.6 0.1nm Lick-Fe5015 ?=- Lick Fe5015 absorption index value in Å (LICK_FE5015) (G1) 581- 595 E15.6 0.1nm e_Lick-Fe5015 []?=- Error on Lick Fe5015 index (LICKFE5015ERR) (G2) 599- 602 I4 --- f_Lick-Fe5015 Warning flag for index measurement (LICKFE5015FLAG) (G3) 606- 620 E15.6 --- Lick-Fe5015-RP ?=- Resolving power of Lick Fe5015 index (LICKFE5015RP) (G4) 624- 638 E15.6 mag Lick-Mg1 ?=- Lick Mg1 absorption index value in mag (LICK_MG1) (G1) 642- 656 E15.6 mag e_Lick-Mg1 []?=- Error on Lick Mg1 index (LICKMG1ERR) (G2) 660- 663 I4 --- f_Lick-Mg1 Warning flag for index measurement (LICKMG1FLAG) (G3) 667- 681 E15.6 --- Lick-Mg1-RP ?=- Resolving power of Lick Mg1 index (LICKMG1RP) (G4) 685- 699 E15.6 mag Lick-Mg2 ?=- Lick Mg2 absorption index value in mag (LICK_MG2) (G1) 703- 717 E15.6 mag e_Lick-Mg2 []?=- Error on Lick Mg2 index (LICKMG2ERR) (G2) 721- 724 I4 --- f_Lick-Mg2 Warning flag for index measurement (LICKMG2FLAG) (G3) 728- 742 E15.6 --- Lick-Mg2-RP ?=- Resolving power of Lick Mg2 index (LICKMG2RP) (G4) 746- 760 E15.6 0.1nm Lick-Mgb ?=- Lick Mgb absorption index value in Å (LICK_MGB) (G1) 764- 778 E15.6 0.1nm e_Lick-Mgb []?=- Error on Lick Mgb index (LICKMGBERR) (G2) 782- 785 I4 --- f_Lick-Mgb Warning flag for index measurement (LICKMGBFLAG) (G3) 789- 803 E15.6 --- Lick-Mgb-RP ?=- Resolving power of Lick Mgb index (LICKMGBRP) (G4) 807- 821 E15.6 0.1nm Lick-Fe5270 ?=- Lick Fe5270 absorption index value in Å (LICK_FE5270) (G1) 825- 839 E15.6 0.1nm e_Lick-Fe5270 []?=- Error on Lick Fe5270 index (LICKFE5270ERR) (G2) 843- 846 I4 --- f_Lick-Fe5270 Warning flag for index measurement (LICKFE5270FLAG) (G3) 850- 864 E15.6 --- Lick-Fe5270-RP ?=- Resolving power of Lick Fe5270 index (LICKFE5270RP) (G4) 868- 882 E15.6 0.1nm Lick-Fe5335 ?=- Lick Fe5335 absorption index value in Å (LICK_FE5335) (G1) 886- 900 E15.6 0.1nm e_Lick-Fe5335 []?=- Error on Lick Fe5335 index (LICKFE5335ERR) (G2) 904- 907 I4 --- f_Lick-Fe5335 Warning flag for index measurement (LICKFE5335FLAG) (G3) 911- 925 E15.6 --- Lick-Fe5335-RP ?=- Resolving power of Lick Fe5335 index (LICKFE5335RP) (G4) 929- 943 E15.6 0.1nm Lick-Fe5406 ?=- Lick Fe5406 absorption index value in Å (LICK_FE5406) (G1) 947- 961 E15.6 0.1nm e_Lick-Fe5406 []?=- Error on Lick Fe5406 index (LICKFE5406ERR) (G2) 965- 968 I4 --- f_Lick-Fe5406 ?=- Warning flag for index measurement (LICKFE5406FLAG) (G3) 972- 986 E15.6 --- Lick-Fe5406-RP ?=- Resolving power of Lick Fe5406 index (LICKFE5406RP) (G4) 990-1004 E15.6 0.1nm Lick-Fe5709 ?=- Lick Fe5709 absorption index value in Å (LICK_FE5709) (G1) 1008-1022 E15.6 0.1nm e_Lick-Fe5709 []?=- Error on Lick Fe5709 index (LICKFE5709ERR) (G2) 1026-1029 I4 --- f_Lick-Fe5709 Warning flag for index measurement (LICKFE5709FLAG) (G3) 1033-1047 E15.6 --- Lick-Fe5709-RP ?=- Resolving power of Lick Fe5709 index (LICKFE5709RP) (G4) 1051-1065 E15.6 0.1nm Lick-Fe5782 ?=- Lick Fe5782 absorption index value in Å (LICK_FE5782) (G1) 1069-1083 E15.6 0.1nm e_Lick-Fe5782 []?=- Error on Lick Fe5782 index (LICKFE5782ERR) (G2) 1087-1090 I4 --- f_Lick-Fe5782 Warning flag for index measurement (LICKFE5782FLAG) (G3) 1094-1108 E15.6 --- Lick-Fe5782-RP ?=- Resolving power of Lick Fe5782 index (LICKFE5782RP) (G4) 1112-1126 E15.6 0.1nm Lick-NaD ?=- Lick NaD absorption index value in Å (LICK_NAD) (G1) 1130-1144 E15.6 0.1nm e_Lick-NaD []?=- Error on Lick NaD index (LICKNADERR) (G2) 1148-1151 I4 --- f_Lick-NaD Warning flag for index measurement (LICKNADFLAG) (G3) 1155-1169 E15.6 --- Lick-NaD-RP ?=- Resolving power of Lick NaD index (LICKNADRP) (G4) 1173-1187 E15.6 mag Lick-TiO1 ?=- Lick TiO1 absorption index value in mag (LICK_TIO1) (G1) 1191-1205 E15.6 mag e_Lick-TiO1 []?=- Error on Lick TiO1 index (LICKTIO1ERR) (G2) 1209-1212 I4 --- f_Lick-TiO1 Warning flag for index measurement (LICKTIO1FLAG) (G3) 1216-1230 E15.6 --- Lick-TiO1-RP ?=- Resolving power of Lick TiO1 index (LICKTIO1RP) (G4) 1234-1248 E15.6 mag Lick-TiO2 ?=- Lick TiO2 absorption index value in mag (LICK_TIO2) (G1) 1252-1266 E15.6 mag e_Lick-TiO2 []?=- Error on Lick TiO2 index (LICKTIO2ERR) (G2) 1270-1273 I4 --- f_Lick-TiO2 Warning flag for index measurement (LICKTIO2FLAG) (G3) 1277-1291 E15.6 --- Lick-TiO2-RP ?=- Resolving power of Lick TiO2 index (LICKTIO2RP) (G4) 1295-1309 E15.6 0.1nm Lick-HdA ?=- Lick Hdelta_A absorption index value in Å (LICKHDA) (G1) 1313-1327 E15.6 0.1nm e_Lick-HdA []?=- Error on Lick Hdelta_A index (LICKHDA_ERR) (G2) 1331-1334 I4 --- f_Lick-HdA Warning flag for index measurement (LICKHDA_FLAG) (G3) 1338-1352 E15.6 --- Lick-HdA-RP ?=- Resolving power of Lick Hdelta_A index (LICKHDA_RP) (G4) 1356-1370 E15.6 0.1nm Lick-HgA ?=- Lick Hgamma_A absorption index value in Å (LICKHGA) (G1) 1374-1388 E15.6 0.1nm e_Lick-HgA []?=- Error on Lick Hgamma_A index (LICKHGA_ERR) (G2) 1392-1395 I4 --- f_Lick-HgA Warning flag for index measurement (LICKHGA_FLAG) (G3) 1399-1413 E15.6 --- Lick-HgA-RP ?=- Resolving power of Lick Hgamma_A index (LICKHGA_RP) (G4) 1417-1431 E15.6 0.1nm Lick-HdF ?=- Lick Hdelta_F absorption index value in Å (LICKHDF) (G1) 1435-1449 E15.6 0.1nm e_Lick-HdF []?=- Error on Lick Hdelta_F index (LICKHDF_ERR) (G2) 1453-1456 I4 --- f_Lick-HdF Warning flag for index measurement (LICKHDF_FLAG) (G3) 1460-1474 E15.6 --- Lick-HdF-RP ?=- Resolving power of Lick Hdelta_F index (LICKHDF_RP) (G4) 1478-1492 E15.6 0.1nm Lick-HgF ?=- Lick Hgamma_F absorption index value in Å (LICKHGF) (G1) 1496-1510 E15.6 0.1nm e_Lick-HgF []?=- Error on Lick Hgamma_F index (LICKHGF_ERR) (G2) 1514-1517 I4 --- f_Lick-HgF Warning flag for index measurement (LICKHGF_FLAG) (G3) 1521-1535 E15.6 --- Lick-HgF-RP ?=- Resolving power of Lick Hgamma_F index (LICKHGF_RP) (G4) 1539-1553 E15.6 --- D4000N ?=- D4000n index value (D4000_N) (G1) 1557-1571 E15.6 --- e_D4000N []?=- Error on D4000n index (D4000NERR) (G2) 1575-1578 I4 --- f_D4000N Warning flag for index measurement (D4000NFLAG) (G3) 1582-1596 E15.6 --- D4000N-RP ?=- Resolving power of D4000n index (D4000NRP) (G4) 1600-1614 E15.6 0.1nm HdHg ?=- Composite HdeltaA+HgammaA absorption index value in Å (HDHG) (G1) 1618-1632 E15.6 0.1nm e_HdHg []?=- Error on HdeltaA+HgammaA index (HDHG_ERR) (G2) 1636-1639 I4 --- f_HdHg Warning flag for index measurement (HDHG_FLAG) (G3) 1643-1657 E15.6 --- HdHg-RP ?=- Resolving power of HdeltaA+HgammaA index (HDHG_RP) (G4) 1661-1675 E15.6 mag Mg2Fe ?=- Composite [Mg2Fe] absorption index value in mag (MG2FE) (G1) 1679-1693 E15.6 mag e_Mg2Fe []?=- Error on [Mg2Fe] index (MG2FE_ERR) (G2) 1697-1700 I4 --- f_Mg2Fe Warning flag for index measurement (MG2FE_FLAG) (G3) 1704-1718 E15.6 --- Mg2Fe-RP ?=- Resolving power of [Mg2Fe] index (MG2FE_RP) (G4) 1722-1736 E15.6 0.1nm MgFep ?=- Composite [MgFe]' absorption index value in Å (MGFE_PRIME) (G1) 1740-1754 E15.6 0.1nm e_MgFep []?=- Error on [MgFe]' index (MGFEPRIMEERR) (G2) 1758-1761 I4 --- f_MgFep Warning flag for index measurement (MGFEPRIMEFLAG) (G3) 1765-1779 E15.6 --- MgFep-RP ?=- Resolving power of [MgFe]' index (MGFEPRIMERP) (G4) 1783-1797 E15.6 0.1nm Mg/Fe ?=- Mgb/<Fe> absorption index value in Å (MG_FE) (G1) 1801-1815 E15.6 0.1nm e_Mg/Fe []?=- Error on Mgb/<Fe> index (MGFEERR) (G2) 1819-1822 I4 --- f_Mg/Fe Warning flag for index measurement (MGFEFLAG) (G3) 1826-1840 E15.6 --- Mg/Fe-RP ?=- Resolving power of Mgb/<Fe> index (MGFERP) (G4) 1844-1858 E15.6 0.1nm MgFe50p ?=- [MgFe50]' absorption index value in Å (MGFE50_PRIME) (G1) 1862-1876 E15.6 0.1nm e_MgFe50p []?=- Error on [MgFe50]' index (MGFE50PRIMEERR) (G2) 1880-1883 I4 --- f_MgFe50p Warning flag for index measurement (MGFE50PRIMEFLAG) (G3) 1887-1901 E15.6 --- MgFe50p-RP ?=- Resolving power of [MgFe50]' index (MGFE50PRIMERP) (G4) 1905-1919 E15.6 0.1nm MgFe52p ?=- [MgFe52]' absorption index value in Å (MGFE52_PRIME) (G1) 1923-1937 E15.6 0.1nm e_MgFe52p []?=- Error on [MgFe52]' index (MGFE52PRIMEERR) (G2) 1941-1944 I4 --- f_MgFe52p Warning flag for index measurement (MGFE52PRIMEFLAG) (G3) 1948-1962 E15.6 --- MgFe52p-RP ?=- Resolving power of [MgFe52]' index (MGFE52PRIMERP) (G4) 1966-1971 I6 --- CombDupl Flag indicating whether the index measurements have been combined between duplicates (COMB_DUPL) (1) 1975-1980 I6 --- UseDupl Flag indicating whether the galaxy entry is the one to be selected among the duplicates (USE_DUPL) (2) 1984-1998 E15.6 10/nm SNRDupl ?=- Squared sum of SNRF4000 of duplicate observations (SNR_DUPL) (3) 2002-2007 I6 --- IDDupl1 ?=- LEGAC_ID of the first duplicate observation (ID_DUPL1) (4) 2008-2013 I6 --- IDDupl2 ?=- LEGAC_ID of the second duplicate observation (ID_DUP21) (4) 2014-2019 I6 --- IDDupl3 ?=- LEGAC_ID of the third duplicate observation (ID_DUPL3) (4) -------------------------------------------------------------------------------- Note (1): Comb_dupl=1 if the index measurements are the error-weighted mean of duplicate observations for the same galaxy. The reported index measurements for all duplicate observations of the same galaxy are the same. Comb_dupl=0 if no duplicate observations have been combined and the index measurement comes directly from the spectrum. Note (2): This flag is meaningful only when comb_dupl=1. In this case use_dupl=1 means the spectrum is the one to be selected among the available duplicates of a given galaxy; use_dupl=0 if there are no usable duplicates or if there is already another entry selected for the same galaxy. Note (3): This quantity is equal to SNRF4000 (the S/N at the rest-frame 4000Å of the individual spectrum as in DR3) if there are no usable duplicate observations. Otherwise, and in combination with use_dupl=1, it is the squared sum of the SNRF4000 of the individual duplicate observations. Note (4): Set to --- if there is no duplicate observation. -------------------------------------------------------------------------------- Byte-by-byte Description of file: stelpop.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 10 I10 --- LEGACID [1/4081] LEGA-C running sequence number (ID of a unique spectrum as in LEGA-C DR3 catalog) (LEGACID) 14- 19 I6 --- BIDXuseMap [0/403] bit map of indices used in the BaStA fit (BASTAIDXUSEMAP) (1) 23- 37 E15.6 [Msun] BlogMP2P5 ?=-99 2.5 percentile of PDF of log stellar mass from BaStA (BASTALOGMP2P5) (G5) 41- 55 E15.6 [Msun] BlogMP16 ?=-99 16 percentile of PDF of log stellar mass from BaStA (BASTALOGMP16) (G5) 59- 73 E15.6 [Msun] BlogMP50 ?=-99 Median of PDF of log stellar mass from BaStA (BASTALOGMP50) (G5) 77- 91 E15.6 [Msun] BlogMP84 ?=-99 84 percentile of PDF of log stellar mass from BaStA (BASTALOGMP84) (G5) 95- 109 E15.6 [Msun] BlogMP97P5 ?=-99 97.5 percentile of PDF of log stellar mass from BaStA (BASTALOGMP97P5) (G5) 113- 127 E15.6 [Msun] BlogMBF ?=-99 log stellar mass of bestfit model from BaStA (BASTALOGMBF) (G5) 131- 145 E15.6 [Sun] BlogZWRP2P5 ?=-99 2.5 percentiles of log r-band-weighted Zstar from BaStA (BASTALOGZWRP2P5) (2),(G5) 149- 163 E15.6 [Sun] BlogZWRP16 ?=-99 16 percentile of log r-band-weighted Zstar from BaStA (BASTALOGZWRP16) (2),(G5) 167- 181 E15.6 [Sun] BlogZWRP50 ?=-99 median of log r-band-weighted Zstar from BaStA (BASTALOGZWRP50) (2),(G5) 185- 199 E15.6 [Sun] BlogZWRP84 ?=-99 84 percentiles of log r-band-weighted Zstar from BaStA (BASTALOGZWRP84) (2),(G5) 203- 217 E15.6 [Sun] BlogZWRP97P5 ?=-99 97.5 percentiles of log r-band-weighted Zstar from BaStA (BASTALOGZWRP97P5) (2),(G5) 221- 235 E15.6 [Sun] BlogZWRBF ?=-99 log r-band weighted Zstar of bestfit model from BaStA (BASTALOGZWRBF) (2),(G5) 239- 253 E15.6 [Sun] BlogZWMP2P5 ?=-99 2.5 percentiles of log mass-weighted Zstar from BaStA (BASTALOGZWMP2P5) (2),(G5) 257- 271 E15.6 [Sun] BlogZWMP16 ?=-99 16 percentile of log mass-weighted Zstar from BaStA (BASTALOGZWMP16) (2),(G5) 275- 289 E15.6 [Sun] BlogZWMP50 ?=-99 median of log mass-weighted Zstar from BaStA (BASTALOGZWMP50) (2),(G5) 293- 307 E15.6 [Sun] BlogZWMP84 ?=-99 84 percentile of log mass-weighted Zstar from BaStA (BASTALOGZWMP84) (2),(G5) 311- 325 E15.6 [Sun] BlogZWMP97P5 ?=-99 97.5 percentile of log mass-weighted Zstar from BaStA (BASTALOGZWMP97P5) (2),(G5) 329- 343 E15.6 [Sun] BlogZWMBF ?=-99 log mass-weighted Zstar bestfit model from BaStA (BASTALOGZWMBF) (2),(G5) 347- 361 E15.6 [yr] BlogAWRP2P5 ?=-99 2.5 percentile of log r-band-weighted age from BaStA (BASTALOGAGEWRP2P5) (3),(G5) 365- 379 E15.6 [yr] BlogAWRP16 ?=-99 16 percentiles of log r-band-weighted age from BaStA (BASTALOGAGEWRP16) (3),(G5) 383- 397 E15.6 [yr] BlogAWRP50 ?=-99 median of log r-band-weighted age from BaStA (BASTALOGAGEWRP50) (3),(G5) 401- 415 E15.6 [yr] BlogAWRP84 ?=-99 84 percentile of log r-band-weighted age from BaStA (BASTALOGAGEWRP84) (3),(G5) 419- 433 E15.6 [yr] BlogAWRP97P5 ?=-99 97.5 percentile of log r-band-weighted age from BaStA (BASTALOGAGEWRP97P5) (3),(G5) 437- 451 E15.6 [yr] BlogAWRBF ?=-99 log r-band-weighted age of bestfit model from BaStA (BASTALOGAGEWRBF) (3),(G5) 455- 469 E15.6 [yr] BlogAWMP2P5 ?=-99 2.5 percentile of log mass-weighted age from BaStA (BASTALOGAGEWMP2P5) (3),(G5) 473- 487 E15.6 [yr] BlogAWMP16 ?=-99 16 percentile of log mass-weighted age from BaStA (BASTALOGAGEWMP16) (3),(G5) 491- 505 E15.6 [yr] BlogAWMP50 ?=-99 median of log mass-weighted age from BaStA (BASTALOGAGEWMP50) (3),(G5) 509- 523 E15.6 [yr] BlogAWMP84 ?=-99 84 percentile of log mass-weighted age from BaStA (BASTALOGAGEWMP84) (3),(G5) 527- 541 E15.6 [yr] BlogAWMP97P5 ?=-99 97.5 percentile of log mass-weighted age from BaStA (BASTALOGAGEWMP97P5) (3),(G5) 545- 559 E15.6 [yr] BlogAWMBF ?=-99 log mass-weighted age of bestfit model from BaStA (BASTALOGAGEWMBF) (3),(G5) 563- 577 E15.6 mag BAGP2P5 ?=-99 2.5 percentile of pdf of dust attenuation in g-band from BaStA (BASTAAGP2P5) (G5) 581- 595 E15.6 mag BAGP16 ?=-99 16 percentile of pdf of dust attenuation in g-band from BaStA (BASTAAGP16) (G5) 599- 613 E15.6 mag BAGP50 ?=-99 median of pdf of dust attenuation in g-band from BaStA (BASTAAGP50) (G5) 617- 631 E15.6 mag BAGP84 ?=-99 84 percentile of pdf of dust attenuation in g-band from BaStA (BASTAAGP84) (G5) 635- 649 E15.6 mag BAGP97P5 ?=-99 97.5 percentile of pdf of dust attenuation in g-band from BaStA (BASTAAGP97P5) (G5) 653- 667 E15.6 mag BAGBF ?=-99 dust attenuation in g-band of bestfit model from BaStA (BASTAAGBF) (G5) 671- 685 E15.6 --- WSilver ?=-99 weight to correct for completeness of silver sample selection (W_SILVER) (4) 689- 703 E15.6 --- WGolden ?=-99 weight to correct for completeness of golden sample selection (W_GOLDEN) (4) 707- 712 I6 --- FlagSilver [0/1] flag for silver sample (FLAG_SILVER) (5) (G6) 716- 721 I6 --- FlagGolden [0/1] flag for golden sample (FLAG_GOLDEN) (5) (G6) 725- 730 I6 --- FlagQ [0/1] flag for quiescent galaxies based on SSFR_UVIR (FLAG_Q) (6) (G6) 734- 739 I6 --- FlagSF [0/1] flag for star-forming galaxies based on SSFR_UVIR (FLAG_SF) (6) (G6) 743- 748 I6 --- UseDupl [0/1] flag for duplicate observation selection (USE_DUPL) (7) 752- 757 I6 --- NDupl [0/3] number of spectra for the same object (NDUPL) (7) 761- 775 E15.6 [Msun/yr] SFRUVIR ?=-99 log SFR based on UV and 24 um (SFR_UVIR) (8) 779- 793 E15.6 [yr-1] SSFRUVIR ?=-99 specific SFR based on UV and 24 um (SSFR_UVIR) (9) 797- 802 I6 --- UVJSFQ [0/1] UVJ selection of Q/SF (UVJ_SFQ) (10) (G6) 806- 820 E15.6 [Sun] PlogZP50 ?=-99 median of pdf of log Zstar from Prospector (PROSPLOGZP50) (11) 824- 838 E15.6 [Sun] PlogZP16 ?=-99 16 percentile of pdf of log Zstar from Prospector (PROSPLOGZP16) (11) 842- 856 E15.6 [Sun] PlogZP84 ?=-99 84 percentile of pdf of log Zstar from Prospector (PROSPLOGZP84) (11) 860- 874 E15.6 mag PAVP50 ?=-99 median of pdf of V-band dust attenuation from Prospector (PROSPAVP50) (11) 878- 892 E15.6 mag PAVP16 ?=-99 16 percentile of pdf of V-band dust attenuation from Prospector (PROSPAVP16) (11) 896- 910 E15.6 mag PAVP84 ?=-99 84 percentile of pdf of V-band dust attenuation from Prospector (PROSPAVP84) (11) 914- 928 E15.6 [Msun] PlogMP50 ?=-99 median of pdf of log Mstar from Prospector (PROSPLOGMP50) (11) 932- 946 E15.6 [Msun] PlogMP16 ?=-99 16 percentile of pdf of log Mstar from Prospector (PROSPLOGMP16) (11) 950- 964 E15.6 [Msun] PlogMP84 ?=-99 84 percentile of pdf of log Mstar from Prospector (PROSPLOGMP84) (11) 968- 982 E15.6 [yr] PlogAWMP50 ?=-99 median of pdf of log mass-weighted age from Prospector (PROSPLOGAGEWMP50) (11) 986-1000 E15.6 [yr] PlogAWMP16 ?=-99 16 percentile of pdf of log mass-weighted age from Prospector (PROSPLOGAGEWMP16) (11) 1004-1018 E15.6 [yr] PlogAWMP84 ?=-99 84 percentile of pdf of log mass-weighted age from Prospector (PROSPLOGAGEWMP84) (11) 1022-1036 E15.6 [yr] PlogAWRP50 ?=-99 median of pdf of log r-band-weighted age from Prospector (PROSPLOGAGEWRP50) (11) 1040-1054 E15.6 [yr] PlogAWRP16 ?=-99 16 percentile of pdf of log r-band-weighted age from Prospector (PROSPLOGAGEWRP16) (11) 1058-1072 E15.6 [yr] PlogAWRP84 ?=-99 84 percentile of pdf of log r-band-weighted age from Prospector (PROSPLOGAGEWRP84) (11) 1076-1090 E15.6 [Msun/yr] PSFRP50 ?=-99 median of log SFR from Prospector (PROSPSFRP50) (11) 1094-1108 E15.6 [Msun/yr] PSFRP16 ?=-99 16 percentile of log SFR from Prospector (PROSPSFRP16) (11) 1112-1126 E15.6 [Msun/yr] PSFRP84 ?=-99 84 percentile of log SFR from Prospector (PROSPSFRP84) (11) 1130-1144 E15.6 [Msun/yr] PSFR100MyrP50 ?=-99 median of log SFR averaged over 100 Myr, from Prospector (PROSPSFR100MYRP50) (11) 1148-1162 E15.6 [Msun/yr] e_PSFR100MyrP50 ?=-99 uncertainty on log SFR averaged over 100 Myr (PROSPSFR100MYRERR) (11) 1166-1180 E15.6 [Sun] BPSlogZP50 ?=-99 median of pdf of log Zstar from Bagpipes (BPSLOGZP50) (12) 1184-1198 E15.6 [Sun] BPSlogZP16 ?=-99 16 percentile of pdf of log Zstar from Bagpipes (BPSLOGZP16) (12) 1202-1216 E15.6 [Sun] BPSlogZP84 ?=-99 84 percentile of pdf of log Zstar from Bagpipes (BPSLOGZP84) (12) 1220-1234 E15.6 mag BPSAVP50 ?=-99 median of pdf of V-band dust attenuation from Bagpipes (BPSAVP50) (12) 1238-1252 E15.6 mag BPSAVP16 ?=-99 16 percentile of pdf of V-band dust attenuation from Bagpipes (BPSAVP16) (12) 1256-1270 E15.6 mag BPSAVP84 ?=-99 84 percentile of pdf of V-band dust attenuation from Bagpipes (BPSAVP84) (12) 1274-1288 E15.6 [Msun] BPSlogMP50 ?=-99 median of pdf of log Mstar from Bagpipes (BPSLOGMP50) (12) 1292-1306 E15.6 [Msun] BPSlogMP16 ?=-99 16 percentile of pdf of log Mstar from Bagpipes (BPSLOGMP16) (12) 1310-1324 E15.6 [Msun] BPSlogMP84 ?=-99 84 percentile of pdf of log Mstar from Bagpipes (BPSLOGMP84) (12) 1328-1342 E15.6 [yr] BPSlogAWMP50 ?=-99 median of pdf of log mass-weighted age from Bagpipes (BPSLOGAGEWMP50) (12) 1346-1360 E15.6 [yr] BPSlogAWMP16 ?=-99 16 percentile of pdf of log mass-weighted age from Bagpipes (BPSLOGAGEWMP16) (12) 1364-1378 E15.6 [yr] BPSlogAWMP84 ?=-99 84 percentile of pdf of log mass-weighted age from Bagpipes (BPSLOGAGEWMP84) (12) 1382-1396 E15.6 [yr] BPSlogAWRP50 ?=-99 median of pdf of log r-band-weighted age from Bagpipes (BPSLOGAGEWRP50) (12) 1400-1414 E15.6 [yr] BPSlogAWRP16 ?=-99 16 percentile of pdf of log r-band-weighted age from Bagpipes (BPSLOGAGEWRP16) (12) 1418-1432 E15.6 [yr] BPSlogAWRP84 ?=-99 84 percentile of pdf of log r-band-weighted age from Bagpipes (BPSLOGAGEWRP84) (12) 1436-1450 E15.6 [Msun/yr] BPSSFRP50 ?=-99 median of pdf of log SFR from Bagpipes (BPSSFRP50) (12) 1454-1468 E15.6 [Msun/yr] BPSSFRP16 ?=-99 16 percentile of pdf of log SFR from Bagpipes (BPSSFRP16) (12) 1469 A1 ---- n_BPSSFRP16 [I] I for -infinity 1472-1486 E15.6 [Msun/yr] BPSSFRP84 ?=-99 84 percentile of pdf of log SFR from Bagpipes (BPSSFRP84) (12) -------------------------------------------------------------------------------- Note (1): Bit-map storing the information about which absorption indices have been used in the BaStA fit. The correspondence between indices and bit is the following: bit 0= Hbeta; 1= D4000n; 2= MgFe_prime, 3= Mg2Fe, 4= HdHg, 5= Hdelta_A, 6= Hgamma_A, 7= MgFe50_PRIME, 8= MgFe52_PRIME. For example, to check whether MgFe_prime was used in the fit, the following condition must be satisfied: (BASTAIDXUSEMAP and uint(2.^2)) eq uint(2.^2) Note (2): Stellar metallicities from BaStA (this paper) are in log and in units of Zsun=0.0154 Note (3): Ages are given in units of log(yr) Note (4): Statistical weights to correct for incompleteness associated to the selection of the silver/golden sample. These weights are defined in the plane of U-V color and absolute g-band luminosity, as described in the paper. These weights are applicable only to galaxies belonging to the silver/golden sample, as defined in the flagsilver/flaggolden entries. For a full volume- and completeness weighing, these weights should be multiplied by TCOR provided in the general LEGA-C DR3 catalog. Note (5): Flag to select galaxies belonging to the silver/golden sample. Meaning: 1= in silver/golden sample; 0= not in silver/golden sample. These flags already account for the general parent sample selection: PRIMARY=1, FLAG_SPEC=0, SIGMASTARSPRIME>0 (where primary, flag_spec and sigmastarsprime come from the LEGA-C DR3 catalog). Silver galaxies are galaxies in the parent sample that satisfy the requirements on availability of absorption features measurement as described in Gallazzi+2026a; golden galaxies are those additionally satisfying the S/N requirement SNRF4000>20 (or SNR_DUPL>20 for duplicate-combined measurements). Moreover, these flags already account for duplicate observations (see Note 7). Therefore by using flag_silver or flag_golden one selects unique galaxies belonging to the silver or golden sample. Note (6): Flag for quiescent/star-forming galaxies based on a cut in specific SFR, where SFR comes from UV+24um calibration (see Note 9). Value is 1 if quiescent/star-forming. To select e.g. golden quiescent galaxies one should require flag_golden eq 1 AND flag_quiescent eq 1. Note (7): When NDUPL is larger than 1 it means that there are duplicate observations for that galaxy. The flag USE_DUPL (in absidx_d.dat) informs whether the corresponding spectroscopic entry is the one to be used in case of duplicate observations (USE_DUPL=1). To select unique galaxies, one should require: NDUPL eq 1 or (NDUPL gt 1 and USE_DUPL eq 1). These requirements are already accounted for if one uses the flag_silver or flag_golden flags. Note (8): (Log of) star formation rate derived from UV and 24um luminosities as described in Gallazzi+2026b. Note (9): The (log) specific star formation rate is obtained by dividing the SFR from UV+24um by the stellar mass estimated with BaStA (SFR_UVIR - BASTALOGMP50) Note (10): Flag to select galaxies into quiescent/star-forming based on the UVJ plane (see van der Wel et al., 2016ApJS..223...29V 2016ApJS..223...29V, Gallazzi et al., Paper II, 2026A&A...708A.290G 2026A&A...708A.290G, Cat. J/A+A/708/A290). 1: quiescent; 0: star-forming. Note (11): Stellar population parameters as derived with Prospector fitting the LEGA-C spectra plus photometry as described in Nersesian et al., 2025A&A...695A..86N 2025A&A...695A..86N. Stellar metallicity is given in units of Zsun=0.02 (note that the normalization is different from the one used in the BaStA estimates). Dust attenuation is provided in the V-band (note that dust attenuation from BaStA is provided in the g-band). PROSP_SFR refers to the instantaneous star formation rate, while PROSP_SFR100MYR is the star formation rate averaged over the past 100 Myr. Note (12): Stellar population parameters as derived with Bagpipes fitting the LEGA-C spectra plus photometry as described in Kaushal et al., 2024ApJ...961..118K 2024ApJ...961..118K. Stellar metallicity is given in units of Zsun=0.02 (note that the normalization is different from the one used in the BaStA estimates). Dust attenuation is provided in the V-band (note that dust attenuation from BaStA is provided in the g-band). -------------------------------------------------------------------------------- Byte-by-byte Description of file: parms.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 5 F5.2 [Msun] logMass Logarithm of the central value of 0.2dex-wide bin of stellar mass (logMass) 9- 12 F4.2 [yr] logAgep50 Median of logarithm light-weighted mean age of silver galaxies in the mass bin (logAge_p50) 16- 20 F5.2 [yr] E_logAgep50 Upper error on median logarithm light-weighted age of silver galaxies in the mass bin (eulogAgep50) 24- 28 F5.2 [yr] e_logAgep50 [] Lower error on median logarithm light-weighted age of silver galaxies in the mass bin (ellogAgep50) 32- 35 F4.2 [yr] logAgep16 16th percentile of logarithm light-weighted age of silver galaxies in the mass bin (logAge_p16) 39- 42 F4.2 [yr] logAgep84 84th percentile of logarithm light-weighted age of silver galaxies in the mass bin (logAge_p84) 46- 49 F4.2 [yr] medelogAge Mean of 84-16 percentile range of individual logAge PDFs for silver galaxies in stellar mass bin (medelogAge) 53- 57 F5.2 [Sun] logZp50 Median of logarithm light-weighted mean metallicity of silver galaxies in the mass bin (logZ_p50) 61- 65 F5.2 [Sun] E_logZp50 Upper error on median logarithm light-weighted metallicity of silver galaxies in the mass bin (eulogZp50) 69- 73 F5.2 [Sun] e_logZp50 [] Lower error on median logarithm light-weighted metallicity of silver galaxies in the mass bin (ellogZp50) 77- 81 F5.2 [Sun] logZp16 16th percentile of logarithm light-weighted metallicity of silver galaxies in the mass bin (logZ_p16) 85- 89 F5.2 [Sun] logZp84 84th percentile of logarithm light-weighted metallicity of silver galaxies in the mass bin (logZ_p84) 93- 96 F4.2 [Sun] medelogZ Mean of 84-16 percentile range of individual logZ PDFs for silver galaxies in stellar mass bin (medelogZ) 100-102 I3 --- Ngal Number of galaxies in mass bin (ngal) -------------------------------------------------------------------------------- Byte-by-byte Description of file: parmg.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 5 F5.2 [Msun] logMass Logarithm of the central value of 0.2dex-wide bin of stellar mass (logMass) 9- 12 F4.2 [yr] logAgep50 Median of logarithm light-weighted mean age of golden galaxies in the mass bin (logAge_p50) 16- 20 F5.2 [yr] E_logAgep50 Upper error on median logarithm light-weighted age of golden galaxies in the mass bin (eulogAgep50) 24- 28 F5.2 [yr] e_logAgep50 [] Lower error on median logarithm light-weighted age of golden galaxies in the mass bin (ellogAgep50) 32- 35 F4.2 [yr] logAgep16 16th percentile of logarithm light-weighted age of golden galaxies in the mass bin (logAge_p16) 39- 42 F4.2 [yr] logAgep84 84th percentile of logarithm light-weighted age of golden galaxies in the mass bin (logAge_p84) 46- 49 F4.2 [yr] medelogAge Mean of 84-16 percentile range of individual logAge PDFs for golden galaxies in stellar mass bin (medelogAge) 53- 57 F5.2 [Sun] logZp50 Median of logarithm light-weighted mean metallicity of golden galaxies in the mass bin (logZ_p50) 61- 65 F5.2 [Sun] E_logZp50 Upper error on median logarithm light-weighted metallicity of golden galaxies in the mass bin (eulogZp50) 69- 73 F5.2 [Sun] e_logZp50 [] Lower error on median logarithm light-weighted metallicity of golden galaxies in the mass bin (ellogZp50) 77- 81 F5.2 [Sun] logZp16 16th percentile of logarithm light-weighted metallicity of golden galaxies in the mass bin (logZ_p16) 85- 89 F5.2 [Sun] logZp84 84th percentile of logarithm light-weighted metallicity of golden galaxies in the mass bin (logZ_p84) 93- 96 F4.2 [Sun] medelogZ Mean of 84-16 percentile range of individual logZ PDFs for golden galaxies in stellar mass bin (medelogZ) 100-101 I2 --- Ngal Number of galaxies in mass bin (ngal) -------------------------------------------------------------------------------- Byte-by-byte Description of file: parss.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 4 F4.2 [km/s] logSigma Logarithm of the central value of 0.1dex-wide bin of stellar velocity dispersion (logSigma) 8- 11 F4.2 [yr] logAgep50 Median of logarithm light-weighted mean age of silver galaxies in the sigma bin (logAge_p50) 15- 19 F5.2 [yr] E_logAgep50 Upper error on median logarithm light-weighted age of silver galaxies in the sigma bin (eulogAgep50) 23- 27 F5.2 [yr] e_logAgep50 [] Lower error on median logarithm light-weighted age of silver galaxies in the sigma bin (ellogAgep50) 31- 34 F4.2 [yr] logAgep16 16th percentile of logarithm light-weighted age of silver galaxies in the sigma bin (logAge_p16) 38- 41 F4.2 [yr] logAgep84 84th percentile of logarithm light-weighted age of silver galaxies in the sigma bin (logAge_p84) 45- 48 F4.2 [yr] medelogAge Mean of 84-16 percentile range of individual logAge PDFs for silver galaxies in sigma bin (medelogAge) 52- 56 F5.2 [Sun] logZp50 Median of logarithm light-weighted mean metallicity of silver galaxies in the sigma bin (logZ_p50) 60- 64 F5.2 [Sun] E_logZp50 Upper error on median logarithm light-weighted metallicity of silver galaxies in the sigma bin (eulogZp50) 68- 72 F5.2 [Sun] e_logZp50 [] Lower error on median logarithm light-weighted metallicity of silver galaxies in the sigma bin (ellogZp50) 76- 80 F5.2 [Sun] logZp16 16th percentile of logarithm light-weighted metallicity of silver galaxies in the sigma bin (logZ_p16) 85- 88 F4.2 [Sun] logZp84 84th percentile of logarithm light-weighted metallicity of silver galaxies in the sigma bin (logZ_p84) 92- 95 F4.2 [Sun] medelogZ Mean of 84-16 percentile range of individual logZ PDFs for silver galaxies in sigma bin (medelogZ) 98-100 I3 --- Ngal Number of galaxies in sigma bin (ngal) -------------------------------------------------------------------------------- Byte-by-byte Description of file: parsg.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 4 F4.2 [km/s] logSigma Logarithm of the central value of 0.1dex-wide bin of stellar velocity dispersion (logSigma) 8- 11 F4.2 [yr] logAgep50 Median of logarithm light-weighted mean age of golden galaxies in the sigma bin (logAge_p50) 15- 19 F5.2 [yr] E_logAgep50 Upper error on median logarithm light-weighted age of golden galaxies in the sigma bin (eulogAgep50) 23- 27 F5.2 [yr] e_logAgep50 [] Lower error on median logarithm light-weighted age of golden galaxies in the sigma bin (ellogAgep50) 31- 34 F4.2 [yr] logAgep16 16th percentile of logarithm light-weighted age of golden galaxies in the sigma bin (logAge_p16) 38- 41 F4.2 [yr] logAgep84 84th percentile of logarithm light-weighted age of golden galaxies in the sigma bin (logAge_p84) 45- 48 F4.2 [yr] medelogAge Mean of 84-16 percentile range of individual logAge PDFs for golden galaxies in sigma bin (medelogAge) 52- 56 F5.2 [Sun] logZp50 Median of logarithm light-weighted mean metallicity of golden galaxies in the sigma bin (logZ_p50) 60- 64 F5.2 [Sun] E_logZp50 Upper error on median logarithm light-weighted metallicity of golden galaxies in the sigma bin (eulogZp50) 68- 72 F5.2 [Sun] e_logZp50 [] Lower error on median logarithm light-weighted metallicity of golden galaxies in the sigma bin (ellogZp50) 76- 80 F5.2 [Sun] logZp16 16th percentile of logarithm light-weighted metallicity of golden galaxies in the sigma bin (logZ_p16) 85- 88 F4.2 [Sun] logZp84 84th percentile of logarithm light-weighted metallicity of golden galaxies in the sigma bin (logZ_p84) 92- 95 F4.2 [Sun] medelogZ Mean of 84-16 percentile range of individual logZ PDFs for golden galaxies in sigma bin (medelogZ) 99-100 I2 --- Ngal Number of galaxies in sigma bin (ngal) -------------------------------------------------------------------------------- Global Notes: Note (G1): Absorption indices are measured on the emission-line subtracted spectra, at the actual spectral resolution (instrumental and velocity dispersion) Note (G2): Observational errors on absorption indices already include a multiplicative factor coming from comparison of duplicate observations (see van der Wel et al., 2021ApJS..256...44V 2021ApJS..256...44V) Note (G3): Byte flag to check quality of index measurement. With the following meaning: bit 0: low frac of good pixels in central band (does not apply to D4000) bit 1: low frac of good pixels in blue band bit 2: extrapolated blue band bit 3: low frac of good pixels in red band bit 4: extrapolated red band For composite indices the warning flag combines the respective flags for individual indices. The index measurement is considered reliable if bit 0, 1, 3 are zero (bit 1 and 3 for D4000 or D4000n). For example for Hbeta, in IDL, one should require: LICKHBFLAG.bitget([0]) eq 0 AND LICKHBFLAG.bitget([1]) eq 0 AND LICKHBFLAG.bitget([3]) eq 0. An additional check on the index error is advisable, such that e.g.: LICKHBERR gt 0 (errors are set to -99 when the measurement failed). Note (G4): The index resolving power is defined as the ratio between the 5-95 percentile range of the index value and the index error, as in the paper. Note (G5): Stellar population parameters as derived with BaStA, fitting selected absorption indices plus photometry as described in the paper. The median of the PDF is taken as the fiducial value, while the 16-84 (2.5-97.5) percentiles give the 1-sigma (2-sigma) uncertainty. The parameter value of the bestfit model is provided for checks but not used in the analysis. Estimates of stellar population parameters are provided for the whole LEGA-C DR3 sample, but note that especially for stellar metallicity the estimates are meaningful only for galaxies in the silver or golden sample, i.e. galaxies with spectral coverage that allows coverage of at least one of the metal-sensitive composite indices (MgFe_PRIME, Mg2Fe, MgFe50_PRIME, MgFe52_PRIME) which means roughly up to z=0.77. Note (G6): **Sample selection** - The general parent sample is selected to satisfy the conditions: PRIMARY=1, FLAG_SPEC=0, SIGMASTARSPRIME>0 (where primary, flag_spec and sigmastarsprime come from the LEGA-C DR3 catalog). To select unique galaxies, one should further select: NDUPL eq 1 or (NDUPL gt 1 and USE_DUPL eq 1). In the paper and Paper II (Gallazzi et al., 2026A&A...708A.290G 2026A&A...708A.290G, we restricted the stellar population analysis to galaxies having at least one of the age-sensitive indices and at least one of the metal-sensitive indices. This defines the silver sample: silver galaxies are galaxies in the parent sample that satisfy the requirements on availability of absorption features measurement as described in Gallazzi+2026a. Golden galaxies are those additionally satisfying the S/N requirement SNRF4000>20 (or SNR_DUPL>20 for duplicate-combined measurements). Galaxies are then classified into Quiescent or Star-Forming based on a mass-dependent cut in specific SFR (SSFR_UVIR) as defined in Gallazzi et al., Paper II (2026A&A...708A.290G 2026A&A...708A.290G). Flag_Q and Flag_SF can be used to identify quiescent and star-forming galaxies respectively, to be used in addition to flagsilver/flaggolden if needed. To select quiescent/star-forming galaxies based on the UVJ plane instead, use the UVJ_SFQ flag. -------------------------------------------------------------------------------- Acknowledgements: Anna Gallazzi, anna.gallazzi(at)inaf.it References: Gallazzi et al., Paper II, 2026A&A...708A.290G 2026A&A...708A.290G, Cat. J/A+A/708/A290 License: CC-BY-4.0 [see https://spdx.org/licenses/] History: 14-Apr-2026: on-line version 16-Apr-2026: corrected absidx.dat and absidx_d.dat tables
(End) Anna Gallazzi [INAF, Italy], Patricia Vannier [CDS] 21-Mar-2026
The document above follows the rules of the Standard Description for Astronomical Catalogues; from this documentation it is possible to generate f77 program to load files into arrays or line by line