J/MNRAS/500/5009 Theoretical scenario for RR Lyrae in Gaia (Marconi+, 2021)
A theoretical scenario for Galactic RR Lyrae in the Gaia data base:
constraints on the parallax offset.
Marconi M., Molinaro R., Ripepi V., Leccia S., Musella I., De Somma G.,
Gatto M., Moretti M.I.
<Mon. Not. R. Astron. Soc., 500, 5009-5023 (2021)>
=2021MNRAS.500.5009M 2021MNRAS.500.5009M (SIMBAD/NED BibCode)
ADC_Keywords: Stars, variable ; Abundances, [Fe/H] ; Abundances, peculiar ;
Effective temperatures ; Parallaxes, trigonometric ; Models ;
Optical
Keywords: stars: abundances - stars: distances - stars: variables: RR Lyrae
Abstract:
On the basis of an extended set of non-linear convective RR Lyrae
pulsation models we derive the first theoretical light curves in the
Gaia bands G, GBP, and GRP and the corresponding
intensity-weighted mean magnitudes and pulsation amplitudes. The
effects of chemical composition on the derived Bailey diagrams in the
Gaia filters are discussed for both Fundamental and first overtone
mode pulsators. The inferred mean magnitudes and colours are used to
derive the first theoretical Period-Wesenheit relations for RR Lyrae
in the Gaia filters. The application of the theoretical
Period-Wesenheit relations for both the Fundamental and first overtone
mode to Galactic RR Lyrae in the Gaia Data Release 2 data base and
complementary information on individual metal abundances allows us to
derive theoretical estimates of their individual parallaxes. These
results are compared with the astrometric solutions to conclude that a
very small offset, consistent with zero, is required in order to
reconcile the predicted distances with Gaia results.
Description:
An extensive set of non-linear convective pulsation models for RR
Lyrae at different metal and helium abundances has been taken into
account. The transformation of bolometric magnitude variations into
the Gaia filters allowed us to derive the first theoretical light
curves directly comparable with Gaia time-series data. In particular,
we built the first theoretical Bailey diagrams and Period-Wesenheit
(PW) relations in the GBP, G, and GRP filters, varying both the
metallicity and the helium content. As for the Bailey diagram, we
conclude that an increase in the metal abundance and/or in the helium
abundance produces a decrease in the pulsation amplitudes, whereas an
increase in the luminosity level produces a period shift towards
longer values.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 74 509 Fundamental model parameters
table2.dat 74 205 First overtone model parameters
tablea1.dat 117 167 Sample of RR Lyrae stars used for the comparison
with the models with metallicity from high
resolution spectroscopy
--------------------------------------------------------------------------------
See also:
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
Byte-by-byte Description of file: table[12].dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 F6.4 --- Z Metal abundance
8- 12 F5.3 --- Y Heluim abundance
14- 19 F6.4 d P Predicted pulsation period
21- 24 F4.2 Msun Mass Mass
26- 30 F5.3 [Lsun] logL Logarithm of the luminosity
32- 35 I4 K Teff Effective temperature
37- 42 F6.3 mag BPmag Inferred mean BP magnitude
44- 48 F5.3 mag AmpBP Inferred pulsation amplitude in the BP-band
50- 55 F6.3 mag Gmag Inferred mean G magnitude
57- 61 F5.3 mag AmpG Inferred pulsation amplitude in the G-band
63- 68 F6.3 mag RPmag Inferred mean RP magnitude
70- 74 F5.3 mag AmpRP Inferred pulsation amplitude in the RP-band
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tablea1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 26 A26 --- Name RR Lyrae name
28- 31 A4 --- Mode Mode of pulsation (1)
33- 41 F9.5 deg RAdeg Right ascension (J2000)
43- 51 F9.5 deg DEdeg Declination (J2000)
53- 58 F6.4 mas plx Gaia DR2 parallax
60- 65 F6.4 mas e_plx Error on plx
67- 71 F5.3 --- ruwe Gaia DR2 renormalized unit-weight error
73- 79 F7.5 d P Pulsation period
81- 86 F6.3 mag Gmag Gaia DR2 G-band magnitude
88- 93 F6.3 mag BPmag ?=99.999 Gaia DR2 BP-band magnitude
95- 100 F6.3 mag RPmag ?=99.999 Gaia DR2 RP-band magnitude
102 I1 --- n Number of averaged measures (2)
104- 108 F5.2 [-] [Fe/H] Iron abundance
110- 113 F4.2 [-] e_[Fe/H] Error on [Fe/H]
115- 117 A3 --- r_[Fe/H] Reference for [Fe/H] (3)
--------------------------------------------------------------------------------
Note (1): Mode of pulsation as follows:
RRab = mean fundamental
RRc = first overtone
RRd = double mode pulsator
Note (2): For APOGEE and GALAH survey n was imposed equal to one
Note (3): Reference as follows:
APO = APOGEE
GAL = GALAH
M18 = Magurno et al. (2018ApJ...864...57M 2018ApJ...864...57M, Cat. J/ApJ/864/57)
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 13-Oct-2023