J/ApJ/852/78 JHKs, WISE and Spitzer data of Galactic Cepheids (Wang+, 2018)
The near-infrared optimal distances method applied to Galactic classical
Cepheids tightly constrains mid-infrared period-luminosity relations.
Wang S., Chen X., de Grijs R., Deng L.
<Astrophys. J., 852, 78 (2018)>
=2018ApJ...852...78W 2018ApJ...852...78W
ADC_Keywords: Stars, variable; Photometry, infrared; Stars, distances
Keywords: distance scale ; dust, extinction ; infrared: ISM ;
stars: variables: Cepheids
Abstract:
Classical Cepheids are well-known and widely used distance indicators.
As distance and extinction are usually degenerate, it is important to
develop suitable methods to robustly anchor the distance scale. Here,
we introduce a near-infrared optimal distance method to determine both
the extinction values of and distances to a large sample of 288
Galactic classical Cepheids. The overall uncertainty in the derived
distances is less than 4.9%. We compare our newly determined distances
to the Cepheids in our sample with previously published distances to
the same Cepheids with Hubble Space Telescope parallax measurements
and distances based on the IR surface brightness method, Wesenheit
functions, and the main-sequence fitting method. The systematic
deviations in the distances determined here with respect to those of
previous publications is less than 1%-2%. Hence, we constructed
Galactic mid-IR period-luminosity (PL) relations for classical
Cepheids in the four Wide-Field Infrared Survey Explorer (WISE) bands
(W1, W2, W3, and W4) and the four Spitzer Space Telescope bands
([3.6], [4.5], [5.8], and [8.0]). Based on our sample of hundreds of
Cepheids, the WISE PL relations have been determined for the first
time; their dispersion is approximately 0.10mag. Using the currently
most complete sample, our Spitzer PL relations represent a significant
improvement in accuracy, especially in the [3.6] band which has the
smallest dispersion (0.066mag). In addition, the average mid-IR
extinction curve for Cepheids has been obtained: AW1/AKs∼0.560,
AW2/AKs∼0.479, AW3/AKs∼0.507, AW4/AKs∼0.406,
A[3.6]/AKs∼0.481, A[4.5]/AKs∼0.469, A[5.8]/AKs∼0.427, and
A[8.0]/AKs∼0.427mag.
Description:
To accurately determine the distances to Galactic classical Cepheids
in near-IR bands, a sample of Galactic classical Cepheids with near-IR
J, H, Ks-band mean magnitudes has been collected from the literature.
van Leeuwen+ (2007MNRAS.379..723V 2007MNRAS.379..723V) published 229 Cepheids with near-IR
mean magnitudes in the South African Astronomical Observatory (SAAO)
system. A sample of Galactic Cepheids with individual Baade-Wesselink
distances was compiled from Fouque+ (2007, J/A+A/476/73), Groenewegen
(2008A&A...488...25G 2008A&A...488...25G), Pedicelli+ (2010A&A...518A..11P 2010A&A...518A..11P), and Storm+
(2011, J/A+A/534/A94). Monson & Pierce (2011, J/ApJS/193/12) provided
near-IR photometric measurements for 131 northern Galactic classical
Cepheids. Chen+ (2017MNRAS.464.1119C 2017MNRAS.464.1119C) used 31 open-cluster Cepheids to
obtain JHKs Galactic Cepheid PL relations. After removing duplicate
sources, our final sample comprises 288 classical Cepheids.
J,H,Ks-band mean magnitudes in the SAAO and European Southern
Observatory systems were converted to the Two Micron All Sky Survey
(2MASS) system. See section 2 for further explanations.
We take the WISE photometric data of our Cepheid sample from the
AllWISE Multi-epoch Photometry Database.
The Galactic Legacy Infrared Midplane Survey Extraordinaire (GLIMPSE)
program is a mid-IR survey in four bands ([3.6], [4.5], [5.8], and
[8.0]) using the Infrared Array Camera (IRAC) on board the Spitzer
Space Telescope. The isophotal central wavelengths are 3.550, 4.439,
5.731, and 7.872um, respectively. The survey data include Spitzer
observations from a number of programs covering the Galactic plane:
GLIMPSE I, GLIMPSE II, GLIMPSE 3D, GLIMPSE 360, Vela-Carina, Deep
GLIMPSE, SMOG, and Cygnus-X (Benjamin+ 2003PASP..115..953B 2003PASP..115..953B ;
Churchwell+ 2009PASP..121..213C 2009PASP..121..213C). We search all catalogs for
photometric data of our sample Cepheids. In addition, Monson et al.
(2012, J/ApJ/759/14) used 37 Galactic Cepheids with Spitzer/IRAC [3.6]
and [4.5]-band photometric measurements to calibrate the Galactic
Cepheid PL relations.
See section 3 for further explanations.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 120 288 2MASS and WISE mean magnitudes and distances for
our sample of 288 Galactic Cepheids
table3.dat 70 135 Spitzer/IRAC mean magnitudes for Galactic Cepheids
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See also:
II/293 : GLIMPSE Source Catalog (I + II + 3D) (IPAC 2008)
II/328 : AllWISE Data Release (Cutri+ 2013)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
J/A+AS/143/211 : Galactic Cepheids BVRI photometry (Berdnikov+, 2000)
J/A+A/404/423 : BVI photometry of Galactic Cepheids (Tammann+, 2003)
J/A+A/476/73 : Cepheid Period/Luminosity relation calib. (Fouque+, 2007)
J/ApJ/707/89 : Variation of mid-IR extinction (Gao+, 2009)
J/ApJS/193/12 : JHK photometry of Northern Galactic Cepheids (Monson+, 2011)
J/ApJ/743/76 : Spitzer photometry of LMC Cepheids (Scowcroft+, 2011)
J/A+A/534/A94 : Milky Way Cepheids radial velocities (Storm+, 2011)
J/ApJ/759/146 : Spitzer/IRAC photom. for 37 Galactic Cepheids (Monson+, 2012)
J/ApJ/747/50 : Distance to Cepheids using Wesenheit function (Ngeow, 2012)
J/MNRAS/420/585 : AKARI observations of SMC Cepheids (Ngeow+, 2012)
J/MNRAS/447/3342 : Galactic & LMC Cepheids Fourier parameters (Bhardwaj+, 2015)
J/AJ/149/117 : LMC infrared survey. I. Photometry of Cepheids (Macri+, 2015)
J/A+A/605/A79 : TGAS Cepheids and RR Lyrae stars (Gaia Collaboration+, 2017)
J/ApJ/842/42 : Improved reddenings for 59 Galactic Cepheids (Madore+, 2017)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- Name Cepheid name
18- 22 F5.3 [d] logPer [0.4/1.9] Log(Period), days from the literature
24- 29 F6.3 mag JmagAvg [0.8/10.2] mean J magnitude in 2MASS system (1)
31- 35 F5.3 mag e_JmagAvg [0.01/0.09] Uncertainty in Jmag
37- 41 F5.3 mag HmagAvg [0.4/9.7] mean H magnitude in 2MASS system (1)
43- 47 F5.3 mag e_HmagAvg [0.01/0.09] Uncertainty in Hmag
49- 53 F5.3 mag KsmagAvg [0.4/9.6] mean Ks magnitude in 2MASS system (1)
55- 59 F5.3 mag e_KsmagAvg [0.01/0.07] Uncertainty in Ksmag
61- 65 F5.3 mag W1magAvg [0.5/9.4]? mean ALLWISE W1 (3.4um) multi-epoch
magnitude
67- 71 F5.3 mag e_W1magAvg [0.02/0.4]? Uncertainty in W1mag
73- 77 F5.3 mag W2magAvg [0.1/9.4]? mean ALLWISE W2 (4.6um) multi-epoch
magnitude
79- 83 F5.3 mag e_W2magAvg [0.02/0.2]? Uncertainty in W2mag
85- 89 F5.3 mag W3magAvg [0.6/9.3]? mean ALLWISE W3 (12um) multi-epoch
magnitude
91- 95 F5.3 mag e_W3magAvg [0.01/0.4]? Uncertainty in W3mag
97-101 F5.3 mag W4magAvg [0.5/7.2]? mean ALLWISE W4 (22um) multi-epoch
magnitude
103-107 F5.3 mag e_W4magAvg [0.02/0.3]? Uncertainty in W4mag
109-114 F6.3 mag DM [5.3/14.8] Derived Distance Modulus
116-120 F5.3 mag e_DM [0.07/0.3] Uncertainty in DM
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Note (1): J, H, Ks-band mean magnitudes in the SAAO and European Southern
Observatory (ESO) systems were converted to the Two Micron All Sky Survey
(2MASS) system using the color transformation equations given on the
2MASS website.
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Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- Name Cepheid name
18- 22 F5.3 [d] logPer [0.4/1.9] Log(Period), days from the literature
24- 28 F5.3 mag 3.6magAvg [0.4/9.4]? mean Spitzer/IRAC 3.6um magnitude (1)
30- 34 F5.3 mag e_3.6magAvg [0.001/0.06]? Uncertainty in 3.6mag
36- 40 F5.3 mag 4.5magAvg [1/9.3]? mean Spitzer/IRAC 4.5um magnitude (1)
42- 46 F5.3 mag e_4.5magAvg [0.001/0.07]? Uncertainty in 4.5mag
48- 52 F5.3 mag 5.8magAvg [4/8.4]? mean Spitzer/IRAC 5.8um magnitude (1)
54- 58 F5.3 mag e_5.8magAvg [0.01/0.05]? Uncertainty in 5.8mag
60- 64 F5.3 mag 8.0magAvg [3.9/8.4]? mean Spitzer/IRAC 8.0um magnitude (1)
66- 70 F5.3 mag e_8.0magAvg [0.01/0.04]? Uncertainty in 8.0mag
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Note (1): See the "Description" section above and section 3 for sources of
Spitzer/IRAC magnitudes.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 18-Sep-2018