J/AJ/149/117 LMC infrared survey. I. Photometry of Cepheids (Macri+, 2015)
Large Magellanic Cloud near-infrared synoptic survey.
I. Cepheid variables and the calibration of the Leavitt Law.
Macri L.M., Ngeow C.-C., Kanbur S.M., Mahzooni S., Smitka M.T.
<Astron. J., 149, 117 (2015)>
=2015AJ....149..117M 2015AJ....149..117M
ADC_Keywords: Surveys ; Magellanic Clouds ; Stars, variable ;
Photometry, infrared
Keywords: distance scale - Magellanic Clouds - stars: variables: Cepheids
Abstract:
We present observational details and first results of a near-infrared
(JHKs) synoptic survey of the central region of the Large Magellanic
Cloud (LMC) using the CPAPIR camera at the CTIO 1.5m telescope. We
covered 18 square degrees to a depth of Ks∼16.5mag and obtained an
average of 16 epochs in each band at any given location. Our catalog
contains more than 3.5x106 sources, including 1417 Cepheid variables
previously studied at optical wavelengths by the OGLE survey. Our
sample of fundamental-mode pulsators represents a nine-fold increase
in the number of these variables with time-resolved, multi-band
near-infrared photometry. We combine our large Cepheid sample and a
recent precise determination of the distance to the LMC to derive a
robust absolute calibration of the near-infrared Leavitt Law for
fundamental-mode and first-overtone Cepheids with 10x better
constraints on the slopes relative to previous work. We also obtain
calibrations for the tip of the red giant branch and the red clump
based on our ensemble photometry which are in good agreement with
previous determinations.
Description:
Images were acquired using the CPAPIR camera at the 1.5m telescope of
the Cerro Tololo Inter-American Observatory, operated by the SMARTS
consortium. CPAPIR uses a 2048*2048 Hawaii-2 infrared array detector
and delivers an effective plate scale at this telescope of
0.983''/pixel, or a field of view of 0.559° on a side. We
requested observations centered on 49 different positions, with
extensive overlap among neighboring fields to enable a robust
photometric cross-calibration.
Observations were obtained in queue mode on 32 separate nights during
three distinct time periods: 2006 November (7 nights), 2007 January (6
nights), and 2007 November (19 nights). Individual fields were
targeted on 7-11 nights, often twice on each night, so that every
location within our survey area was observed on 14-20 distinct epochs.
We requested observations centered on 49 different positions, with
extensive overlap among neighboring fields to enable a robust
photometric cross-calibration.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 34 180467 Cepheid photometry
table3.dat 81 1417 Cepheid properties
table4.dat 113 22 Quality flags for Cepheid light curves
table5.dat 84 66 Additional Cepheids from Persson et al. 2004
(cat. J/AJ/128/2239)
tablea1.dat 83 3537039 Ensemble photometry
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See also:
II/288 : IRSF Magellanic Clouds Point Source Catalog (Kato+ 2007)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
J/ApJ/799/144 : M31 Cepheids in near-IR (Kodric+, 2015)
J/MNRAS/424/1807 : VISTA Magellanic Cloud Survey. V. Cepheids (Ripepi+, 2012)
J/MNRAS/419/1637 : Nearby red clump stars JHK observations (Laney+, 2012)
J/AcA/58/163 : VI light curves of LMC classical Cepheids (Soszynski+, 2008)
J/MNRAS/369/723 : Fourier parameters for Cepheid variables (Ngeow+, 2006)
J/AJ/128/2239 : JHKs photometry of 92 LMC Cepheids (Persson+, 2004)
J/ApJS/142/71 : BVRI observations of LMC Cepheids (Sebo+, 2002)
J/PASP/111/812 : VRI Phot of Cepheids in the Magellanic Clouds (Barnes+ 1999)
J/AcA/49/223 : BVI photometry of OGLE LMC Cepheids (Udalski+, 1999)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 4 I04 --- Star [473/3370] Cepheid number (1)
6 A1 --- Flt [JHK] Filter in which the magnitude was obtained
(J, H, or Ks)
8- 15 F8.4 d MJD Modified Julian Date of observation (JD-2450000)
17- 21 F5.3 --- Phase [0/1] Light curve phase (2)
23- 28 F6.3 mag mag [9.9/18.3] Magnitude in Filter
30- 34 F5.3 mag e_mag 1σ uncertainty in mag
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Note (1): From the OGLE-III catalog (Soszynksi et al. 2008, cat. J/AcA/58/163).
Note (2): Based on Period and TI,max from the OGLE catalogs (Soszynksi et al.
2008, cat. J/AcA/58/163; Ulaczyk et al., 2013AcA....63..159U 2013AcA....63..159U).
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 4 I04 --- Star [473/3370] Cepheid number (1)
6- 11 F6.3 d Per [0.2/53] Period (1)
13- 14 A2 --- Mode Pulsation mode (FU=FUndamental,
FO=First-Overtone) (1)
16- 21 F6.3 mag <Vmag> [12.1/19.1]?=99.999 Mean V-band magnitude (1)
23- 28 F6.3 mag <Imag> [11.2/18.3] Mean I-band magnitude (1)
30- 35 F6.3 mag <Jmag> [10.7/17.7]?=99.999 Mean J-band magnitude (2)
37- 42 F6.3 mag <Hmag> [10.1/17.1]?=99.999 Mean H-band magnitude (2)
44- 49 F6.3 mag <Kmag> [10.3/16.5]?=99.999 Mean Ks-band magnitude (2)
51- 53 I3 mmag e_<Jmag> ?=999 1σ uncertainty in Jmag
55- 57 I3 mmag e_<Hmag> ?=999 1σ uncertainty in Hmag
59- 61 I3 mmag e_<Kmag> ?=999 1σ uncertainty in Kmag
63- 65 I3 mmag Jamp ?=999 Light curve amplitude in J-band
67- 69 I3 mmag Hamp ?=999 Light curve amplitude in H-band
71- 73 I3 mmag Kamp ?=999 Light curve amplitude in Ks-band
75- 77 I3 mmag E(V-I) The (V-I) color excess From Haschke et al.
(2011AJ....141..158H 2011AJ....141..158H)
79 A1 --- Q [A-G] Quality flag; A=best (see table4)
81 A1 --- Fit [YN] Used in final fit: Y=Yes,
N=No (rejected based on color-color residuals)
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Note (1): From the OGLE catalogs (Soszynksi et al. 2008, cat. J/AcA/58/163, or
Ulaczyk et al., 2013AcA....63..159U 2013AcA....63..159U).
Note (2): Corrected for crowding as described in Section 2.4, but not for
extinction.
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- Mode Pulsation mode (FU=FUndamental, FO=First-Overtone)
4 A1 --- Q [A-G] Quality bin (A--G)
6- 50 A45 --- Note Decription of the quality flag
52-109 A58 --- Range Range
111-113 I3 --- Ns [13/564]? Number of stars
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- P04 Cepheid identifier from Persson et al. 2004
(cat. J/AJ/128/2239)
9- 11 A3 --- --- [OGL]
13- 16 I4 --- Star [46/3320]? Number of the Cepheid (1)
18- 23 F6.3 d Per [2.6/99.2] Period
25- 30 F6.3 mag <Vmag> [11.9/16.2]?=99.999 Mean V-band magnitude (2)
32- 37 F6.3 mag <Imag> [10.8/15.5]?=99.999 Mean I-band magnitude (2)
39- 44 F6.3 mag <Jmag> [10/15] Mean J-band magnitude (3)
46- 51 F6.3 mag <Hmag> [9.5/14.7] Mean H-band magnitude (3)
53- 58 F6.3 mag <Kmag> [9.4/14.6] Mean Ks-band magnitude (3)
60- 62 I3 mmag e_<Jmag> Uncertainty in <Jmag>
64- 66 I3 mmag e_<Hmag> Uncertainty in <Hmag>
68- 70 I3 mmag e_<Kmag> Uncertainty in <Kmag>
72- 74 I3 mmag E(V-I) The (V-I) color excess (4)
76 A1 --- Fit [Y] Used in final fit (Y=Yes)
78- 84 A7 --- r_<Imag> Source of V and I photometry (5)
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Note (1): From the OGLE catalogs (Soszynksi et al. 2008, cat. J/AcA/58/163;
Ulacyzk et al., 2013AcA....63..159U 2013AcA....63..159U).
Note (2): Not extinction corrected.
Note (3): Not extinction corrected. Transformed into the 2MASS system from the
original observations.
Note (4): From Haschke et al. (2011AJ....141..158H 2011AJ....141..158H) when available or
Persson et al. 2004 (cat. J/AJ/128/2239).
Note (5): The reference codes are defined as follows:
M79 = Martin et al. (1979MNRAS.188..139M 1979MNRAS.188..139M);
F85 = Freedman et al. (1985ApJS...59..311F 1985ApJS...59..311F);
B99 = Barnes et al. 1999 (cat. J/PASP/111/812);
T99 = Tanvir et al. (1999MNRAS.304..957T 1999MNRAS.304..957T);
S02 = Sebo et al. 2002 (cat. J/ApJS/142/71);
N06 = Ngeow et al. 2006 (cat. J/MNRAS/369/723);
S08 = Soszynski et al. 2008 (cat. J/AcA/58/163);
U13 = Ulacyzk et al. (2013AcA....63..159U 2013AcA....63..159U);
S14 = Soszynski, private communication.
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Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 8 F8.5 deg RAdeg Right Ascension in decimal degrees (J2000)
10- 18 F9.5 deg DEdeg Declination in decimal degrees (J2000)
20- 25 F6.3 mag <Jmag> [5/19]? Mean magnitude in J band (1)
27- 32 F6.3 mag <Hmag> [4.5/18.2]? Mean magnitude in H band (1)
34- 39 F6.3 mag <Kmag> [5.6/17]? Mean Ks band magnitude (1)
41- 45 F5.3 mag e_<Jmag> ? Uncertainty in Jmag
47- 51 F5.3 mag e_<Hmag> ? Uncertainty in Hmag
53- 57 F5.3 mag e_<Kmag> ? Uncertainty in Kmag
59- 64 F6.3 --- SJ [-1.1/35.3]? J-Stetson index for J-band data (2)
66- 73 F8.3 --- SH [-2.1/212.5]? J-Stetson index for H-band data
75- 80 F6.3 --- SKs [-0.5/34.4]? J-Stetson index for Ks-band data
82- 83 I2 --- Fld [1/49] Field number (3)
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Note (1): Magnitudes were corrected for crowding using the procedure detailed
in Section 2.4, but have not been corrected for extinction.
Note (2): Objects with J-Stetson variability indices greater than 0.75 are
likely to be variable; mean magnitudes should be considered approximate.
Note (3): We requested observations centered on 49 different positions, with
extensive overlap among neighboring fields to enable a robust photometric
cross-calibration.
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History:
From electronic version of the journal
References:
Bhardwaj et al. Paper II. 2016AJ....151...88B 2016AJ....151...88B, Cat. J/AJ/151/88
Bhardwaj et al. Paper III. 2016MNRAS.457.1644B 2016MNRAS.457.1644B
Bhardwaj et al. Paper IV. 2017AJ....153..154B 2017AJ....153..154B, Cat. J/AJ/153/154
Yuan et al. Paper V. 2017AJ....154..149Y 2017AJ....154..149Y
(End) Greg Schwarz [AAS], Sylvain Guehenneux [CDS] 21-Apr-2015