J/ApJ/779/7 dSph satellites of M31. I. Variables in And XIX (Cusano+, 2013)
Dwarf spheroidal satellites of M31.
I. Variable stars and stellar populations in Andromeda XIX.
Cusano F., Clementini G., Garofalo A., Cignoni M., Federici L., Marconi M.,
Musella I., Ripepi V., Boutsia K., Fumana M., Gallozzi S., Testa V.
<Astrophys. J., 779, 7 (2013)>
=2013ApJ...779....7C 2013ApJ...779....7C
ADC_Keywords: Galaxies, nearby ; Photometry, UBV ; Stars, variable
Keywords: galaxies: dwarf; galaxies: individual: Andromeda XIX;
Local Group; stars: distances; stars: variables: general;
techniques: photometric
Abstract:
We present B, V time-series photometry of Andromeda XIX (And XIX), the
most extended (half-light radius of 6.2') of Andromeda's dwarf
spheroidal companions, which we observed with the Large Binocular
Cameras at the Large Binocular Telescope. We surveyed a 23'x23' area
centered on And XIX and present the deepest color-magnitude diagram
(CMD) ever obtained for this galaxy, reaching, at V∼26.3mag, about one
magnitude below the horizontal branch (HB). The CMD shows a prominent
and slightly widened red giant branch, along with a predominantly red
HB, which extends to the blue to significantly populate the classical
instability strip. We have identified 39 pulsating variable stars, of
which 31 are of RR Lyrae type and 8 are Anomalous Cepheids (ACs).
Twelve of the RR Lyrae variables and three of the ACs are located
within And XIX's half light radius. The average period of the
fundamental mode RR Lyrae stars (<Pab>=0.62days, σ=0.03days)
and the period-amplitude diagram qualify And XIX as an
Oosterhoff-Intermediate system. From the average luminosity of the RR
Lyrae stars (<V(RR)≥25.34mag, σ=0.10mag), we determine a
distance modulus of (m-M)0=24.52±0.23mag in a scale where the
distance to the Large Magellanic Cloud (LMC) is 18.5±0.1mag. The ACs
follow a well-defined Period-Wesenheit (PW) relation that appears to
be in very good agreement with the PW relationship defined by the ACs
in the LMC.
Description:
Time series B, V photometry of And XIX was obtained in fall 2010 using
the Large Binocular Cameras (LBC) mounted at the foci of the Large
Binocular Telescope (LBT). We obtained 44 B and 31 V images each
corresponding to a 420s exposure, for total exposure times of 18480s
and 13020s in B and V, respectively.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 75 39 Identification and properties of the variable
stars identified in And XIX (updated version
from the author)
table3.dat 31 2328 B, V photometry of the variable stars detected
in And XIX
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See also:
II/294 : The SDSS Photometric Catalog, Release 7 (Adelman-McCarthy+, 2009)
J/MNRAS/437/2307 : LMC anomalous Cepheid Ks light curves (Ripepi+, 2014)
J/AJ/147/13 : Disturbers of nearby giant galaxies (Karachentsev+, 2014)
J/AJ/146/86 : Cosmicflows-2 catalog (Tully+, 2013)
J/AJ/145/101 : Updated nearby galaxy catalog (Karachentsev+, 2013)
J/ApJ/768/172 : Kinematic analysis of red giant in M31 dSphs (Collins+, 2013)
J/ApJ/765/71 : VI light curves of RRL stars in M31 (Contreras Ramos+, 2013)
J/MNRAS/435/1928 : Dwarf galaxy planes in Local Group (Pawlowski+, 2013)
J/ApJ/758/11 : Bayesian distances to M31 satellites (Conn+, 2012)
J/A+A/544/A155 : HST photometry of M31 globular clusters (Federici+, 2012)
J/AJ/144/4 : Dwarf galaxies in the Local Group (McConnachie+, 2012)
J/ApJ/743/19 : Variable star candidates photometry in M31 (Clementini+, 2011)
J/AJ/142/199 : Sizes and luminosities of stellar systems (Brodie+, 2011)
J/AJ/141/171 : RR Lyrae stars in 6 ultra-deep fields of M31 (Jeffery+, 2011)
J/AJ/138/184 : RR Lyrae variables in 2 fields of M31 (Sarajedini+, 2009)
J/AcA/58/293 : Type-II and anomalous Cepheids in LMC (Soszynski+, 2008)
J/AJ/132/926 : Galaxies in the Hubble Ultra Deep Field (Coe+, 2006)
J/AJ/129/2232 : Variable stars in And I and And III (Pritzl+, 2005)
J/AJ/127/318 : BV photometry of Andromeda II variables (Pritzl+, 2004)
J/AJ/124/1464 : Variable stars in Andromeda VI (Pritzl+, 2002)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- Name Variable star identifier (VNN) (1)
5 A1 --- f_Name [a] Observed in B only (2)
7- 8 I2 h RAh [0] Hour of right ascension (J2000)
10- 11 I2 min RAm [18/20] Minute of right ascension (J2000)
13- 18 F6.3 s RAs Second of right ascension (J2000)
20 A1 --- DE- [+] Sign of declination (J2000)
21- 22 I2 deg DEd [34/35] Degree of declination (J2000)
24- 25 I2 arcmin DEm Arcminute of declination (J2000)
27- 31 F5.2 arcsec DEs Arcsecond of declination (J2000)
33- 36 A4 --- Type Variable type (RRab (23 stars), RRc (8 stars)
or AC (Anomalous Cepheid; 8 stars)
38- 43 F6.4 d Per [0.3/1.4] Pulsation period
45- 53 F9.3 d HJD Heliocentric Julian Date of maximum light;
JD-2400000
55- 59 F5.2 mag <Bmag> [24.2/26.2] Intensity-averaged mean B-band
magnitude (3)
61- 65 F5.2 mag <Vmag> [23.8/25.7]? Intensity-averaged mean V-band
magnitude
67- 70 F4.2 mag Bamp [0.3/1.6] B-band amplitude
72- 75 F4.2 mag Vamp [0.3/1.3]? V-band amplitude
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Note (1): We assigned to the variables an increasing number starting from the
galaxy center, for which we adopted McConnachie et al.
(2008ApJ...688.1009M 2008ApJ...688.1009M)'s coordinates.
Note (2): a = Only B light curves are available for these stars.
Note (3): The values were obtained by adding to the instrumental values
the zero point of the B calibration equation.
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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- 3 A3 --- Name Variable star identifier (as in table 2)
5 A1 --- Filt Filter used in the observation (B or V)
7- 10 A4 --- Type Variable type (as in table 2)
12- 20 F9.5 d HJD Heliocentric Julian Date; HJD-2455000
22- 26 F5.2 mag mag [23.2/28.7] Observed magnitude in Filt
28- 31 F4.2 mag e_mag [0.01/0.4] The 1σ uncertainty in mag
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History:
* 29-Apr-2015: From electronic version of the journal
* 04-Jul-2015: Insert into VizieR
* 25-Sep-2015: Updated version of table 2 with accurate coordinates;
we acknowledge Felice Cusano [INAF-Osservatorio Astronomico di Bologna]
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 29-Apr-2015