J/ApJS/235/16 UV emission of stars in LAMOST. I. Catalogs (Bai+, 2018)
The UV emission of stars in the LAMOST survey.
I. Catalogs.
Bai Yu, Liu J., Wicker J., Wang S., Guo J., Qin Y., He L., Wang J., Wu Y.,
Dong Y., Zhang Y., Hou Y., Wang Y., Cao Z.
<Astrophys. J. Suppl. Ser., 235, 16 (2018)>
=2018ApJS..235...16B 2018ApJS..235...16B
ADC_Keywords: Photometry, ultraviolet; Photometry, infrared; Extinction;
Spectral types; Effective temperatures; Stars, white dwarf
Keywords: stars: activity ; stars: general ; ultraviolet: stars
Abstract:
We present the ultraviolet magnitudes for over three million stars in
the LAMOST survey, in which 2,202,116 stars are detected by GALEX. For
889,235 undetected stars, we develop a method to estimate their upper
limit magnitudes. The distribution of (FUV-NUV) shows that the color
declines with increasing effective temperature for stars hotter than
7000K in our sample, while the trend disappears for the cooler stars
due to upper atmosphere emission from the regions higher than their
photospheres. For stars with valid stellar parameters, we calculate
the UV excesses with synthetic model spectra, and find that the (FUV -
NUV) versus R'FUV can be fitted with a linear relation and late-type
dwarfs tend to have high UV excesses. There are 87,178 and 1,498,103
stars detected more than once in the visit exposures of GALEX in the
FUV and NUV, respectively. We make use of the quantified photometric
errors to determine statistical properties of the UV variation,
including intrinsic variability and the structure function on the
timescale of days. The overall occurrence of possible false positives
is below 1.3% in our sample. UV absolute magnitudes are calculated for
stars with valid parallaxes, which could serve as a possible reference
frame in the NUV. We conclude that the colors related to UV provide
good criteria to distinguish between M giants and M dwarfs, and the
variability of RR Lyrae stars in our sample is stronger than that of
other A and F stars.
Description:
The design of LAMOST enables it to take 4000 spectra in a single
exposure to a limiting magnitude as faint as r=19 at resolution
R=1800. In 2015 May 30, LAMOST finished its third-year survey (DR3)
and the all-sky coverage is ∼35%. The stars of our sample are
extracted from the catalog with the following criteria: class=STAR and
subclass= from O to M (Luo+ 2015, V/146); this yields 4,010,635 stars.
We cross-match the stars with the ALLWISE catalog (Cutri+ 2013, II/328);
see section 2.2.
We cross-match the stars to GALEX Releases 6 and 7 (GR6/GR7,
see Cat. II/335) in order to obtain their photometry in the FUV and NUV;
see section 2.3.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
targets.dat 83 3091351 List of targets; table added by CDS
table1.dat 134 11987109 UV data in our catalog
table2.dat 81 1730936 UV parameters in our catalog
table3.dat 53 17428 White dwarf-main sequence (WDMS) candidates
in our catalog
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See also:
II/312 : GALEX-DR5 (GR5) sources from AIS and MIS (Bianchi+ 2011)
II/328 : AllWISE Data Release (Cutri+ 2013)
V/146 : LAMOST DR1 catalogs (Luo+, 2015)
V/149 : LAMOST DR2 catalogs (Luo+, 2016)
II/335 : Revised catalog of GALEX UV sources (GUVcat_AIS GR6+7) (Bianchi+ 2017)
V/153 : LAMOST DR4 catalogs (Luo+, 2018)
J/AJ/130/825 : GALEX ultraviolet variability catalog (Welsh+, 2005)
J/ApJS/173/673 : M dwarf UV flares in GALEX (Welsh+, 2007)
J/AJ/136/2050 : SEGUE stellar parameter pipeline. II. (Lee+, 2008)
J/AJ/136/259 : 2nd GALEX UV variability catalog (GUVV-2) (Wheatley+, 2008)
J/ApJ/703/614 : UV star-forming regions in M31 (Kang+, 2009)
J/ApJ/708/717 : Light curve templates of RR Lyrae stars (Sesar+, 2010)
J/other/RAA/11.924 : Atmospheric parameters for 771 stars (Wu+, 2011)
J/ApJ/765/154 : RR Lyrae stars in the Catalina Sky Survey (Drake+, 2013)
J/ApJ/766/60 : GALEX Time Domain Survey I. UV var. sources (Gezari+, 2013)
J/AJ/146/34 : IR photometry of DA white dwarfs from LAMOST (Zhang+, 2013)
J/MNRAS/433/3398 : WD main-sequence binaries (Rebassa-Mansergas+, 2013)
J/ApJ/766/9 : GALEX observations of exoplanet host stars (Shkolnik, 2013)
J/MNRAS/431/2063 : UV/X-ray activity of M dwarfs within 10pc (Stelzer+, 2013)
J/MNRAS/441/1230 : RRLyr stars in the Catalins Sky Survey (CS2) (Abbas+, 2014)
J/A+A/570/A107 : WDMS from LAMOST DR1 (Ren+, 2014)
J/MNRAS/445/2758 : KIC giants Bayesian dist. and extinctions (Rodrigues+ 2014)
J/ApJ/793/62 : Triangulum-Andromeda stellar properties (Sheffield+, 2014)
J/ApJ/798/41 : GALEX NUV obs. of bright M-type stars (Ansdell+, 2015)
J/ApJ/813/100 : Deep GALEX NUV survey of Kepler field. I. (Olmedo+, 2015)
J/MNRAS/448/822 : LAMOST candidate members of star clusters (Xiang+, 2015)
J/MNRAS/452/765 : WD candidates using LAMOST DR3 (Gentile Fusillo+, 2015)
J/MNRAS/454/2787 : LAMOST DR2 white dwarfs (Guo+, 2015)
J/other/RAA/15.1154 : M-giant star candidates in LAMOST DR 1 (Zhong+, 2015)
J/ApJ/817/1 : Palomar/MSU & SDSS-DR7 M dwarfs with GALEX (Jones+, 2016)
J/MNRAS/460/3179 : APOGEE stars distance and extinction (Wang+, 2016)
J/other/RMxAA/53.439 : Gaia stars with GALEX NUV excess (Makarov, 2017)
http://www.galex.caltech.edu/ : GALEX home page
Byte-by-byte Description of file: targets.dat
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Bytes Format Units Label Explanations
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1- 9 I9 --- ObsID [101002/351115238] ObsID in the LAMOST
DR3 catalog
11- 15 A5 --- SpT Spectral types
17- 21 I5 K Teff [2544/40000] Effective temperatures from the
AFGK catalog or estimated with the stellar
subclasses
23- 26 F4.2 [cm/s2] logg [0.02/5]? Surface gravity
28- 32 F5.2 mag Afuv [0/21.6] Extinction in the FUV
34- 38 F5.2 mag Anuv [0/32] Extinction in the NUV
40 I1 --- fE [0/1] Flags of extinction (calculated with
0=the RJCE method or 1=Bayesian method)
42- 60 A19 --- LAMOST LAMOST identifier (JHHMMSS.ss+DDMMSS.s) from DR4
or DR2; blank if object from DR3
62- 72 F11.7 deg RAdeg [0/360] Right ascension (J2000)
74- 83 F10.7 deg DEdeg [-10/63] Declination (J2000)
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
2- 10 I9 --- ObsID [101002/351115238] ObsID in the LAMOST
DR3 catalog
12- 16 A5 --- SpT Spectral types
18- 22 I5 K Teff [2544/40000]? Effective temperatures (1)
24- 27 F4.2 [cm/s2] logg [0.02/5]? Surface Gravity
29- 33 F5.2 mag Afuv [0/21.6]? Extinction in the FUV
35- 39 F5.2 mag Anuv [0/32]? Extinction in the NUV
41 I1 --- fE [0/1]? Flags of extinction (2)
43- 51 F9.4 d JD [2798.1/5964.1] Julian date of observation;
JD-2450000
53- 57 F5.2 mag lFUVvis [14.5/25.1]? FUV upper limit magnitudes
from visit exposures
59- 63 F5.2 mag lNUVvis [-9.6/25.5]? NUV upper limit magnitudes
from visit exposures
65- 66 I2 --- fC [0/26] Visit exposures flag (3)
68- 72 F5.2 mag FUVvis [8.8/24.7]? FUV magnitudes from visit exposures
74- 78 F5.2 mag e_FUVvis [0/35]? Errors for FUVvis
80- 84 F5.2 mag NUVvis [-4.2/29.6]? FUV magnitudes from visit exposures
86- 90 F5.2 mag e_NUVvis [0/68]? Errors for NUVvis
92 A1 --- mark1 Counterpart flag for visit exposures (4)
94 I1 --- f_FUVvis [0/1]? Artifact flag for FUVvis (5)
96 I1 --- f_NUVvis [0/1]? Artifact flag for NUVvis (5)
98-102 F5.2 mag lFUV [14.5/25.1]? FUV upper limit magnitudes
from co-added exposures
104-108 F5.2 mag lNUV [-9.3/25.5]? NUV upper limit magnitudes
from co-added exposures
110-114 F5.2 mag FUV [9.3/26]? FUV magnitude from co-added exposures
116-120 F5.2 mag e_FUV [0/35]? Errors for FUV
122-126 F5.2 mag NUV [-4.1/27]? NUV magnitude from co-added exposures
128-132 F5.2 mag e_NUV [0/27]? Errors for NUV
134 A1 --- mark2 Counterpart flag for co-added exposures (4)
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Note (1): From the AFGK catalog or estimated with the stellar subclasses.
Note (2): Flags of extinction as follows:
0 = extinction calculated with the RJCE method;
1 = extinction calculated with Bayesian method.
Note (3): The visit exposures flag is equal to the number of co-added
exposures for the detected stars.
Note (4):
* = stars with more than one counterparts within 5" in the same visit
or co-add exposure.
Note (5): Flags for the stars with flag_artifact>1 in the FUV and NUV,
when fC=1.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 I9 --- ObsID [101008/351115238] ObsID in the LAMOST
DR3 catalog
11- 16 F6.2 mag EFUV [-24/4.1]? Excesses in the FUV
18- 22 F5.2 mag e_EFUV [0.07/17.3]? Errors of EFUV
24- 29 F6.2 mag ENUV [-19.8/7.8]? Excesses in the NUV
31- 35 F5.2 mag e_ENUV [0.02/22.1]? Errors of ENUV
37- 42 F6.2 [-] RFUV [-11.1/-1.4]? Normalized FUV excesses
44- 48 F5.2 [-] e_RFUV [-9.5/7.5]? Errors of RFUV
50- 55 F6.2 [-] RNUV [-12/3.4]? Normalized NUV excesses
57- 61 F5.2 [-] e_RNUV [-9.2/11.3]? Errors of RNUV
63- 66 F4.2 mag SigFUV [0/4.8]? Intrinsic variabilities in the FUV
68- 71 F4.2 mag SigNUV [0/4]? Intrinsic variabilities in the NUV
73- 76 F4.2 mag SdFUV [0/5.8]? Structure functions on timescales of
days, FUV (1344-1768Å)
78- 81 F4.2 mag SdNUV [0/5.1]? Structure functions on timescales of
days, NUV (1771-2831Å)
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Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 I9 --- ObsID [102042/351112222] ObsID in the LAMOST
DR3 catalog
11- 15 F5.2 mag FUVmag [10.8/24.3] FUV (1344-1768Å) mean magnitude
corrected for extinction (1)
17- 20 F4.2 mag e_FUVmag [0/7] Errors of the FUV (1)
22- 26 F5.2 mag NUVmag [9.4/24.2] NUV (1771-2831Å) mean magnitude
corrected for extinction (1)
28- 31 F4.2 mag e_NUVmag [0/7.7] Errors of the NUV (1)
33- 37 F5.2 mag W1mag [6.6/17.3] AllWISE W1-band (3.4um) magnitude
corrected for extinction
39- 42 F4.2 mag e_W1mag [0.02/0.3]? Errors of the W1
44- 48 F5.2 mag W2mag [6.8/17.3] AllWISE W2-band (4.6um) magnitude
corrected for extinction
50- 53 F4.2 mag e_W2mag [0.02/0.4]? Errors of the W2
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Note (1): Mean magnitudes calculated from all the magnitudes in the visit
exposures.
The errors are derived from the errors of all the magnitudes
in the visit exposures
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Acknowledgements:
Yu Bai [National Astronomical Observatories of China]
History:
From electronic version of the journal
LAMOST IAU identifiers (JHHMMSS.ss+DDMMSS.s) have been retrieved in
LAMOST DR4 (V/153) and then DR2 (V/149).
Coordinates have been sent by the author.
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 22-Aug-2018