J/MNRAS/495/3087 Photometric sample of 2.6million red clump stars (Lucey+, 2020)
From the inner to outer Milky Way: a photometric Sample of
2.6 million red clump stars.
Lucey M., Ting Y.-S., Ramachandra N.S., Hawkins K.
<Mon. Not. R. Astron. Soc. 495, 3087-3103 (2020)>
=2020MNRAS.495.3087L 2020MNRAS.495.3087L (SIMBAD/NED BibCode)
ADC_Keywords: Milky Way ; Associations, stellar ; Stars, giant
Keywords: techniques: photometric - stars: distances - stars: evolution
Abstract:
Large pristine samples of red clump stars are highly sought after
given that they are standard candles and give precise distances even
at large distances. However, it is difficult to cleanly select red
clumps stars because they can have the same Teff and logg as red giant
branch stars. Recently, it was shown that the asteroseismic
parameters, {DELTA}P and {DELTA}ν, which are used to accurately
select red clump stars, can be derived from spectra using the change
in the surface carbon to nitrogen ratio ([C/N]) caused by mixing
during the red giant branch. This change in [C/N] can also impact the
spectral energy distribution. In this study, we predict the {DELTA}P,
{DELTA}ν, Teff and logg using 2MASS, AllWISE, Gaia, and Pan-STARRS
data in order to select a clean sample of red clump stars. We achieve
a contamination rate of ∼20%, equivalent to what is achieved when
selecting from Teff and logg derived from low resolution spectra.
Finally, we present two red clump samples. One sample has a
contamination rate of ∼20% and ∼405000 red clump stars. The other has
a contamination of ∼33% and ∼2.6 million red clump stars which
includes ∼75000 stars at distances >10kpc. For |b|>30 degrees we find
∼15000 stars with contamination rate of ∼9%. The scientific potential
of this catalog for studying the structure and formation history of
the Galaxy is vast given that it includes millions of precise
distances to stars in the inner bulge and distant halo where
astrometric distances are imprecise.
Description:
We selected red clump stars from the 200 million stars which have
photometry from 2MASS (Cat. II/246), AllWISE (Cat. II/328), Gaia (Cat.
I/345), and Pan-STARRS (Cat. II/349). We derive the Teff, logg,
{DELTA}ν, and {DELTA}P of these stars from 13 bands of photometry
and parallax using a mixture density network.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
catalog.dat 140 7491040 Photometrically derived Teff, logg, {DELTA}P and
{DELTA}{NU} for all giant stars along with
distances for selected RC stars
--------------------------------------------------------------------------------
See also:
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
II/328 : AllWISE Data Release (Cutri+ 2013)
II/349 : The Pan-STARRS release 1 (PS1) Survey, DR1 (Chambers+, 2016)
J/AJ/121/327 : Metal Abundances of Red Clump Stars in NGC6819
(Bragaglia+, 2001)
J/MNRAS/382/553 : Abundances of nearby red clump giants (Liu+, 2007)
J/PAZh/34/868 : Red giant clump in the Tycho-2 catalog (Gontcharov, 2008)
J/BaltA/18/141 : North America/Pelican red clump giants ugriJHK
(Straizys+, 2009)
J/A+A/522/A79 : Faint, high-Galactic-latitude red clump stars
(Valentini+, 2010)
J/ApJ/721/L28 : Red clump stars in Galactic Bulge from OGLE-III
(Nataf+, 2010)
J/A+A/527/A40 : Faint, high-Galactic-latitude red clump stars
(Saguner+, 2011)
J/MNRAS/419/1637 : Nearby red clump stars JHK observations (Laney+, 2012)
J/MNRAS/421/3362 : Kinematics of galactic red clump stars (Bilir+, 2012)
J/A+A/555/A91 : Kinematics of bulge red clump stars (Vasquez+, 2013)
J/MNRAS/469/4718 : Kepler red-clump stars in NGC6819 and NGC6791
(Bossini+, 2017)
J/ApJ/858/L7 : Red clump stars selected from LAMOST and APOGEE
(Ting+, 2018)
Byte-by-byte Description of file: catalog.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 I19 --- GaiaDR2 Gaia DR2 source id
21- 41 E21.19 deg RAdeg Right ascension (ICRS) at Ep=2015.5
43- 64 E22.19 deg DEdeg Declination (ICRS) at Ep=2015.5
66- 71 F6.1 K Teff Inferred effective temperature
73- 78 F6.1 K e_Teff Error on the inferred effective temperature
80- 83 F4.2 [cm/s2] logg Inferred surface gravity
85- 89 F5.2 [cm/s2] e_logg Error on the inferred surface gravity
91- 95 F5.1 s deltap Inferred period spacing
97-101 F5.1 s e_deltap Error on the inferred period spacing
103-107 F5.2 Hz deltanu Inferred frequency separation
109-113 F5.2 Hz e_deltanu Error on the inferred frequency separation
115-120 A6 --- Sel The red clump selection tier (1)
122-140 F19.16 kpc Dist ? The distance based on the magnitude for
red clump stars
--------------------------------------------------------------------------------
Note (1): red clump selection tier as follows:
tier 1 = less contaminated sample, contamination rate of ∼20% (405839 RC stars)
tier 2 = contamination rate of ∼33% (2208150 RC staris)
nan = not analysed (4877051 stars)
--------------------------------------------------------------------------------
Acknowledgements:
Madeline Lucey, m_lucey(at)utexas.edu
(End) Patricia Vannier [CDS] 23-Jun-2020