J/AcA/73/105 OGLE delta Scuti stars in LMC (Soszynski+, 2023)
The OGLE Collection of Variable Stars. Over 15 000 delta Scuti Stars in the
Large Magellanic Cloud.
Soszynski I., Pietrukowicz P., Udalski A., Skowron J., Szymanski M.K.,
Poleski R., Skowron D.M., Kozlowski S., Mroz P., Iwanek P., Wrona M.,
Ulaczyk K., Rybicki K., Gromadzki M., Mroz M.
<Acta Astron. 73, 105 (2023)>
=2023AcA....73..105S 2023AcA....73..105S (SIMBAD/NED BibCode)
ADC_Keywords: Magellanic Clouds ; Stars, variable ; Photometry ; Optical
Keywords: stars: variables: delta Scuti - stars: oscillations -
Magellanic Clouds - catalogs
Abstract:
We present the OGLE collection of delta Scuti stars in the Large
Magellanic Cloud and in its foreground. Our dataset encompasses a
total of 15256 objects, constituting the largest sample of
extragalactic delta Sct stars published so far. In the case of 12
delta Sct pulsators, we detected additional eclipsing or ellipsoidal
variations in their light curves. These are the first known candidates
for binary systems containing delta Sct components beyond the Milky
Way. We provide observational parameters for all variables, including
pulsation periods, mean magnitudes, amplitudes, and Fourier
coefficients, as well as long-term light curves in the I- and V-bands
collected during the fourth phase of the OGLE project.
We construct the period-luminosity (PL) diagram, in which
fundamental-mode and first-overtone delta Sct stars form two nearly
parallel ridges. The latter ridge is an extension of the PL relation
obeyed by first-overtone classical Cepheids. The slopes of the PL
relations for delta Sct variables are steeper than those for classical
Cepheids, indicating that the continuous PL relation for
first-overtone delta Sct variables and Cepheids is non-linear,
exhibiting a break at a period of approximately 0.5d.
We also report the enhancement of the OGLE collection of Cepheids and
RR Lyr stars with newly identified and reclassified objects, including
pulsators contained in the recently published Gaia DR3 catalog of
variable stars. As a by-product, we estimate the contamination rate in
the Gaia DR3 catalogs of Cepheids and RR Lyr variables.
Description:
We presented the OGLE collection of about 15000 delta Sct variables
in the LMC.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
ident.dat 136 15256 Identification of stars
(26 Aug 2025 version)
dsct.dat 238 15256 Parameters of delta Scuti stars
remarks.dat 92 111 Remarks on selected objects
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See also:
J/AcA/71/189 : OGLE Galactic bulge and disk delta Scuti (Soszynski+, 2021)
J/AcA/72/245 : OGLE delta Scuti stars in SMC (Soszynski+, 2022)
ftp.astrouw.edu.pl/ogle/ogle4/OCVS/ : OGLE 4 Variable Home Page
Byte-by-byte Description of file: ident.dat
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Bytes Format Units Label Explanations
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1- 19 A19 --- Star Star's ID, OGLE-LMC-DSCT-NNNNN
22- 31 A10 --- Type Type (singlemode, multimode)
34- 35 I2 h RAh Right ascension (J2000.0)
37- 38 I2 min RAm Right ascension (J2000.0)
40- 44 F5.2 s RAs Right ascension (J2000.0)
46 A1 --- DE- Declination sign (J2000)
47- 48 I2 deg DEd Declination (J2000)
50- 51 I2 arcmin DEm Declination (J2000)
53- 56 F4.1 arcsec DEs Declination (J2000)
59- 74 A16 --- OGLE-IV OGLE-IV ID
76- 90 A15 --- OGLE-III OGLE-III ID
92-107 A16 --- OGLE-II OGLE-II ID
109-136 A28 --- OName Other designation
(GCVS, OGLE-I, MACHO, ASAS-SN)
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Byte-by-byte Description of file: dsct.dat
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Bytes Format Units Label Explanations
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1- 19 A19 --- Star Star's ID, OGLE-LMC-DSCT-NNNN
22- 27 F6.3 mag <Imag> Intensity mean I-band magnitude
29- 34 F6.3 mag <Vmag> ?=- Intensity mean V-band magnitude
37- 46 F10.8 d P1 Primary period
48- 57 F10.8 d e_P1 Uncertainty of primary period
60- 69 F10.5 d T0.1 Time of maximum brightness (HJD-2450000)
72- 76 F5.3 mag Iamp.1 I-band amplitude (maximum-minimum)
79- 83 F5.3 --- R21.1 Fourier coefficient R_21
85- 89 F5.3 --- phi21.1 ?=-Fourier coefficient phi_21
92- 96 F5.3 --- R31.1 Fourier coefficient R_31
98-102 F5.3 --- phi31.1 ?=- Fourier coefficient phi_31
105-114 F10.8 d P2 ?=- Secondary period (if available)
116-125 F10.8 d e_P2 ?=- Uncertainty of secondary period
128-137 F10.5 d T0.2 ?=- Time of maximum brightness (HJD-2450000)
140-144 F5.3 mag Iamp.2 ?=- I-band amplitude (maximum-minimum)
147-151 F5.3 --- R21.2 ?=- Fourier coefficient R21
153-157 F5.3 --- phi21.2 ?=- Fourier coefficient phi21
160-164 F5.3 --- R31.2 ?=- Fourier coefficient R31
166-170 F5.3 --- phi31.2 ?=- Fourier coefficient phi31
173-182 F10.8 d P3 ?=- Tertiary period (if available)
184-193 F10.8 d e_P3 ?=- Uncertainty of tertiary period
196-205 F10.5 d T0.3 ?=- Time of maximum brightness (HJD-2450000)
208-212 F5.3 mag Iamp.3 ?=- I-band amplitude (maximum-minimum)
215-219 F5.3 --- R21.3 ?=- Fourier coefficient R21
221-225 F5.3 --- phi21.3 ?=- Fourier coefficient phi21
228-232 F5.3 --- R31.3 ?=- Fourier coefficient R31
234-238 F5.3 --- phi31.3 ?=- Fourier coefficient phi31
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Byte-by-byte Description of file: remarks.dat
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Bytes Format Units Label Explanations
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1- 19 A19 --- Star Star's ID, OGLE-LMC-DSCT-NNNN
21- 92 A72 --- Rem Remark
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History:
Copied at https://www.astrouw.edu.pl/ogle/ogle4/OCVS/lmc/dsct/
(End) Patricia Vannier [CDS] 26-Aug-2025