J/A+A/644/A95 omega Cen RR Lyrae and Type II Cepheids (Braga+, 2020)
Separation between RR Lyrae and Type II Cepheids and their importance
for distance determination: the case of omega Cen.
Braga V.F., Bono G., Fiorentino G., Stetson P.B., Dall'Ora M.,
Salaris M., da Silva R., Fabrizio M., Marinoni S., Marrese M.P.,
Mateo M., Matsunaga N., Monelli M., Wallerstein G.
<Astron. Astrophys. 644, A95 (2020)>
=2020A&A...644A..95B 2020A&A...644A..95B (SIMBAD/NED BibCode)
ADC_Keywords: Stars, variable - Clusters, globular - Stars, distances
Keywords: stars: variables: Cepheids - stars: variables: RR Lyrae -
galaxies: clusters: individual: omega Cen - stars: distances
Abstract:
The separation between RR Lyrae (RRLs) and type II Cepheid (T2Cs)
variables based on their period is debated. Both types of variable
stars are distance indicators, and we aim to promote the use of T2Cs
as distance indicators in synergy with RRLs.
We adopted new and existing optical and Near-Infrared (NIR) photometry
of omega Cen to investigate several diagnostics (colour-magnitude
diagram, Bailey diagram, Fourier decomposition of the light curve,
amplitude ratios) for the empirical separation between Type II
Cepheids (T2Cs) and RR Lyrae (RRLs). We also derived NIR
period-luminosity relations and found a distance modulus of
13.65±0.07 (err.)±0.01 (sigma) mag, in agreement with the recent
literature. We also found that RRLs and T2Cs obey the same PL
relations in the NIR.
Description:
We provide optical and NIR mean magnitudes and amplitudes for the
seven T2Cs in omega Cen. We also provide the list of candidate RRab in
the Galactic Bulge, corrected classification for several Halo T2Cs,
V-band amplitudes of T2Cs in the Bulge, the pulsation and photometric
properties of T2Cs in Globular Clusters and the distance moduli
derived using the NIR PLs.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 19 15 List of candidate RRab in the Bulge
table2.dat 46 28 Updated classification of Halo T2Cs
table3.dat 37 924 V-band amplitudes of Bulge T2Cs
table7.dat 23 4 Distance modulus of omega Cen from PLs
tablea1.dat 133 8 Astrometric properties and classification of T2Cs
tableb1.dat 143 7 Optical properties and periods of the T2Cs
tableb2.dat 80 7 NIR properties and periods of the T2Cs
tableggc.dat 122 59 Properties of T2Cs in Globular Clusters
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See also:
J/AcA/68/315 : OGLE Galactic Cepheids (Udalski+, 2018)
J/A+A/625/A14 : Reclassification of Cepheids in the Gaia DR2 (Ripepi+, 2019)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 19 A19 --- ID OGLE-IV ID, OGLE-BLG-T2CEP-NNNN (1)
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Note (1): Full ID, while the paper only provides the last four digits.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Variable name (GCVS)
11- 29 I19 --- GaiaDR2 ID from Gaia DR2
31- 33 A3 --- ClassR19 Classification in Ripepi et al.
(2019A&A...625A..14R 2019A&A...625A..14R, Cat. J/A+A/625/A14)
35- 42 A8 --- ClassNew Our classification
44- 46 A3 --- r_ClassNew Reference for new classification (1)
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Note (1): References as follows:
1 = ASAS
2 = ASASSN
3 = GCVS
4 = Gaia DR2 (Ripepi et al. 2019A&A...625A..14R 2019A&A...625A..14R, Cat. J/A+A/625/A14)
5 = Warren & Harvey (1976MNRAS.175..129W 1976MNRAS.175..129W)
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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- 19 A19 --- ID OGLE-IV ID, OGLE-BLG-T2CEP-NNNN (1)
21- 28 F8.4 mag AmpV ?=-99.0000 V-band amplitude
30- 37 F8.4 mag e_AmpV ?=-99.0000 uncertainty on V-band amplitude
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Note (1): Full ID, while the paper only provides the last four digits.
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Byte-by-byte Description of file: table7.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- Band PL relation adopted to derive the distance
modulus
6- 11 F6.3 mag DM Distance modulus
13- 17 F5.3 mag e_DM Uncertainty on the distance modulus
19- 23 F5.3 mag s_DM sigma on the distance modulus
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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- 9 A9 --- Name Name of the object
11- 29 I19 --- GaiaDR2 ?=-9999 ID from Gaia DR2
31- 44 A14 --- Type ? Variable type
46- 49 A4 --- AHBtype ? AHB classification
51- 60 F10.6 deg RAdeg Right Ascension (ICRS) at Ep=2015.5 from Braga
et al. (2016AJ....152..170B 2016AJ....152..170B,
Cat. J/AJ/152/170)
62- 71 F10.6 deg DEdeg Declination (ICRS) at Ep=2015.5 from Braga et
al. (2016AJ....152..170B 2016AJ....152..170B, Cat. J/AJ/152/170)
73- 82 F10.6 deg RAGdeg Right Ascension from Gaia DR2
(ICRS) at Ep=2015.5
84- 93 F10.6 deg DEGdeg Declination from Gaia DR2 (ICRS) at Ep=2015.5
95-103 F9.3 uas/yr pmRA ?=-9999.000 Gaia DR2 Proper motion along RA
direction, pmRA*cosDE
105-113 F9.3 uas/yr e_pmRA ?=-9999.000 Uncertainty on Gaia DR2 Proper
motion along RA direction
115-123 F9.3 uas/yr pmDE ?=-9999.000 Gaia DR2 Proper motion along DEC
direction
125-133 F9.3 uas/yr e_pmDE ?=-9999.000 Uncertainty on Gaia DR2 Proper
motion along DEC direction
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Byte-by-byte Description of file: tableb1.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- Name Name of the object (VNN),
Cl* NGC 5139 SAW VNN in Simbad
5- 14 F10.7 d Per Pulsation period
16- 21 F6.3 mag Umag U-band mean magnitude
23- 27 F5.3 mag e_Umag Uncertainty on U-band mean magnitude
29- 34 F6.3 mag Bmag B-band mean magnitude
36- 40 F5.3 mag e_Bmag Uncertainty on B-band mean magnitude
42- 47 F6.3 mag Vmag V-band mean magnitude
49- 53 F5.3 mag e_Vmag Uncertainty on V-band mean magnitude
55- 60 F6.3 mag Rmag R-band mean magnitude
62- 66 F5.3 mag e_Rmag Uncertainty on R-band mean magnitude
68- 73 F6.3 mag Imag I-band mean magnitude
75- 79 F5.3 mag e_Imag Uncertainty on I-band mean magnitude
81- 86 F6.3 mag AmpU ?=-9.999 U-band amplitude
88- 93 F6.3 mag e_AmpU ?=-9.999 Uncertainty on U-band amplitude
95- 99 F5.3 mag AmpB B-band amplitude
101-105 F5.3 mag e_AmpB Uncertainty on B-band amplitude
107-111 F5.3 mag AmpV V-band amplitude
113-117 F5.3 mag e_AmpV Uncertainty on V-band amplitude
119-124 F6.3 mag AmpR ?=-9.999 R-band amplitude
126-131 F6.3 mag e_AmpR ?=-9.999 Uncertainty on R-band amplitude
133-137 F5.3 mag AmpI I-band amplitude
139-143 F5.3 mag e_AmpI Uncertainty on I-band amplitude
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Byte-by-byte Description of file: tableb2.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- Name Name of the object
5- 10 F6.3 mag Jmag J-band mean magnitude
12- 16 F5.3 mag e_Jmag Uncertainty on J-band mean magnitude
18- 23 F6.3 mag Hmag H-band mean magnitude
25- 29 F5.3 mag e_Hmag Uncertainty on H-band mean magnitude
31- 36 F6.3 mag Ksmag Ks-band mean magnitude
38- 42 F5.3 mag e_Ksmag Uncertainty on Ks-band mean magnitude
44- 48 F5.3 mag AmpJ J-band amplitude
50- 54 F5.3 mag e_AmpJ Uncertainty on J-band amplitude
56- 61 F6.3 mag AmpH ?=-9.999 H-band amplitude
63- 68 F6.3 mag e_AmpH ?=-9.999 Uncertainty on H-band amplitude
70- 74 F5.3 mag AmpKs Ks-band amplitude
76- 80 F5.3 mag e_AmpKs Uncertainty on Ks-band amplitude
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Byte-by-byte Description of file: tableggc.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- GCname Name of the Cluster
10- 13 A4 --- ID Variable star ID (VNNN)
15- 24 F10.6 deg RAdeg Right Ascension (J2000)
26- 35 F10.6 deg DEdeg Declination (J2000)
37- 43 F7.4 d Per Pulsation period
45- 50 F6.3 mag meanmag Mean magnitude (in the sixth column passband)
52- 56 F5.3 mag Ampl Amplitude (in the sixth column passband)
58 A1 --- Band Passband for meanmag and Ampl
60- 66 F7.3 mag Jmag ?=-99.0 J-band mean magnitude
68- 74 F7.3 mag Hmag ?=-99.0 H-band mean magnitude
76- 82 F7.3 mag Ksmag ?=-99.0 Ks-band mean magnitude
84- 90 F7.3 mag e_Jmag ?=-99.0 Uncertainty on J-band mean magnitude
92- 98 F7.3 mag e_Hmag ?=-99.0 Uncertainty on H-band mean magnitude
100-106 F7.3 mag e_Ksmag ?=-99.0 Uncertainty on Ks-band mean magnitude
108-112 F5.2 mag DM Distance modulus of the cluster
114-118 F5.3 mag E(B-V) Reddening of the cluster
120-122 A3 --- r_DM Reference paper for DM and E(B-V) (1)
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Note (1): References as follows:
1 = Kunder et al. (2013AJ....145...33K 2013AJ....145...33K)
2 = Sollima et al. (2006MNRAS.372.1675S 2006MNRAS.372.1675S)
3 = Harris (1996AJ....112.1487H 1996AJ....112.1487H)
4 = Ferraro et al. (1999AJ....118.1738F 1999AJ....118.1738F)
5 = Valenti et al. (2007AJ....133.1287V 2007AJ....133.1287V)
6 = Valenti et al. (2010MNRAS.402.1729V 2010MNRAS.402.1729V)
7 = Kaisler et al. (1997PASP..109..920K 1997PASP..109..920K)
8 = Ivanov et al. (2000A&A...362L...1I 2000A&A...362L...1I)
9 = Lazaro et al. (2006MNRAS.372...69L 2006MNRAS.372...69L)
10 = this paper
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Acknowledgements:
Vittorio Francesco Braga, vittorio.braga(at)inaf.it
(End) Vittorio Francesco Braga [INAF-OAR], Patricia Vannier [CDS] 13-Oct-2020