J/ApJ/850/137 ISLAndS project. III. Variable stars (Martinez-Vazquez+, 2017)
The ISLAndS project.
III. Variable stars in six Andromeda dwarf spheroidal galaxies.
Martinez-Vazquez C.E., Monelli M., Bernard E.J., Gallart C., Stetson P.B.,
Skillman E.D., Bono G., Cassisi S., Fiorentino G., McQuinn K.B.W.,
Cole A.A., McConnachie A.W., Martin N.F., Dolphin A.E., Boylan-Kolchin M.,
Aparicio A., Hidalgo S.L., Weisz D.R.
<Astrophys. J., 850, 137 (2017)>
=2017ApJ...850..137M 2017ApJ...850..137M
ADC_Keywords: Stars, variable; Galaxies, nearby; Photometry, HST;
Photometry, UBVRI
Keywords: binaries: eclipsing ; galaxies: dwarf ; galaxies: stellar content ;
stars : horizontal-branch ; stars: variables: Cepheids ;
stars: variables: RR Lyrae
Abstract:
We present a census of variable stars in six M31 dwarf spheroidal
satellites observed with the Hubble Space Telescope. We detect 870
RR Lyrae (RRL) stars in the fields of And I (296), II (251), III
(111), XV (117), XVI (8), and XXVIII (87). We also detect a total of
15 Anomalous Cepheids, three eclipsing binaries, and seven field RRL
stars compatible with being members of the M31 halo or the Giant
Stellar Stream. We derive robust and homogeneous distances to the six
galaxies using different methods based on the properties of the RRL
stars. Working with the up-to-date set of Period-Wesenheit (I, B-I)
relations published by Marconi et al., we obtain distance moduli of
µ0=[24.49, 24.16, 24.36, 24.42, 23.70, 24.43]mag (respectively),
with systematic uncertainties of 0.08mag and statistical uncertainties
<0.11mag. We have considered an enlarged sample of 16 M31 satellites
with published variability studies, and compared their pulsational
observables (e.g., periods and amplitudes) with those of 15 Milky Way
satellites for which similar data are available. The properties of the
(strictly old) RRL in both satellite systems do not show any
significant difference. In particular, we found a strikingly similar
correlation between the mean period distribution of the fundamental
RRL pulsators (RRab) and the mean metallicities of the galaxies. This
indicates that the old RRL progenitors were similar at the early stage
in the two environments, suggesting very similar characteristics for
the earliest stages of evolution of both satellite systems.
Description:
Table 1 presents a compilation of updated values for the position of
the center, absolute MV magnitude, reddening (E(B-V)), and
structural parameters for each of the six observed galaxies under the
ISLAndS project (hereafter called ISLAndS galaxies).
The data for these six ISLAndS galaxies have been obtained under
proposals GO-13028 and GO-13739 for a total of 111 HST orbits. They
consist of one ACS pointing on the central region and a WFC3 parallel
field (at 6' from the ACS center) for each galaxy. For further details
about the ACS and WFC3 field location, the reader is referred to
Figure 4 of Skillman+ (2017ApJ...837..102S 2017ApJ...837..102S), where the strategy and
the description of the ISLAndS project is explained in depth.
Summary of HST observations (table 2):
--------------------------------------
Galaxy Obs. dates Orbits
--------------------------------------
And I 2015 Sep 1-6 22
And II 2013 Oct 4-6 17
And III 2014 Nov 24-28 22
And XV 2014 Sep 17-20 17
And XVI 2013 Nov 20-22 13
And XXVIII 2015 Jan 20-25 20
--------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 93 6 Positions and structural parameters for
the ISLAndS galaxies
a1andi.dat 78 88 Observing log for And I dSph
a1andii.dat 78 68 Observing log for And II dSph
a1andiii.dat 78 88 Observing log for And III dSph
a1andxv.dat 78 68 Observing log for And XV dSph
a1andxvi.dat 78 52 Observing log for And XVI dSph
a1and28.dat 78 80 Observing log for And XXVIII dSph
b2andi.dat 66 6644 Photometry of the variable stars in AndI dSph
b2andii.dat 66 4369 Photometry of the variable stars in AndII dSph
b2andiii.dat 66 2552 Photometry of the variable stars in AndIII dSph
b2andxv.dat 66 2057 Photometry of the variable stars in AndXV dSph
b2andxvi.dat 66 117 Photometry of the variable stars in AndXVI dSph
b2and28.dat 66 1800 Photometry of the variable stars
in AndXXVIII dSph
c3andi.dat 116 100 Cross-identification with the
Pritzl+ (2004, J/AJ/127/318 and
2005, J/AJ/129/2232) catalog of
variable stars in And I dSph
c3andii.dat 50 73 Cross-identification with the
Pritzl+ (2004, J/AJ/127/318 and
2005, J/AJ/129/2232) catalog of
variable stars in And II dSph
c3andiii.dat 170 56 Cross-identification with the
Pritzl+ (2004, J/AJ/127/318 and
2005, J/AJ/129/2232) catalog of
variable stars in And III dSph
d4andi.dat 124 302 Pulsation parameters of the variable stars
in And I dSph
d4andii.dat 124 257 Pulsation parameters of the variable stars
in And II dSph
d4andiii.dat 124 116 Pulsation parameters of the variable stars
in And III dSph
d4andxv.dat 123 121 Pulsation parameters of the variable stars
in And XV dSph
d4andxvi.dat 123 9 Pulsation parameters of the variable stars
in And XVI dSph
d4and28.dat 123 90 Pulsation parameters of the variable stars
in And XXVIII dSph
--------------------------------------------------------------------------------
See also:
B/hst : HST Archived Exposures Catalog (STScI, 2007)
J/AJ/110/2166 : Variables in Sextans dSph galaxy (Mateo+ 1995)
J/AJ/117/1313 : NGC 6441 VI photometry (Layden+, 1999)
J/AJ/120/284 : Variables in Leo II dwarf spheroidal (Siegel+, 2000)
J/AJ/124/3222 : VI photometry of Draco and UMi galaxies (Bellazzini+, 2002)
J/AJ/123/3154 : RV light curves of variable stars in Leo A (Dolphin+, 2002)
J/AJ/124/1464 : Variable stars in Andromeda VI (Pritzl+, 2002)
J/AJ/127/318 : BV photometry of Andromeda II variables (Pritzl+, 2004)
J/A+A/431/1189 : BV photometry of NGC 6822 variables (Baldacci+, 2005)
J/AJ/129/267 : RR Lyrae variables in NGC 5272 (Cacciari+, 2005)
J/AJ/129/2232 : Variable stars in And I and And III (Pritzl+, 2005)
J/other/RMxAA/44.365 : New variable stars in NGC 6366 (Arellano Ferro+, 2008)
J/AJ/136/1921 : Variable stars of Draco dSph (Kinemuchi+, 2008)
J/ApJ/674/L81 : Variable stars in dwarf galaxy CVn I (Kuehn+, 2008)
J/ApJ/699/1742 : LCID project. I. Cetus and Tucana variables (Bernard+, 2009)
J/ApJ/712/1259 : LCID project. II. Variables in IC1613 (Bernard+, 2010)
J/AJ/141/171 : RR Lyrae stars in ultra-deep fields of M31 (Jeffery+, 2011)
J/AJ/142/107 : Variable stars in NGC 1466 (Kuehn+, 2011)
J/ApJ/758/11 : Bayesian distances to M31 satellites (Conn+, 2012)
J/A+A/539/A138 : RR Lyr variable stars in M32 (Fiorentino+, 2012)
J/AJ/144/4 : Dwarf galaxies in the Local Group (McConnachie+, 2012)
J/MNRAS/422/89 : Cetus dSph RR Lyrae (Monelli+, 2012)
J/ApJ/756/121 : Variable stars in Her dwarf galaxy (Musella+, 2012)
J/ApJ/779/7 : M31 dSph satellites. I. Variables in And XIX (Cusano+, 2013)
J/ApJ/767/62 : RR Lyrae stars BV photometry in UMa I (Garofalo+, 2013)
J/ApJ/779/102 : Metallicities of RGB stars in dwarf galaxies (Kirby+, 2013)
J/ApJ/786/147 : RR Lyrae pop. in the Phoenix dwarf galaxy (Ordonez+, 2014)
J/AcA/64/177 : VI LCs of Galactic Bulge RR Lyrae (Soszynski+, 2014)
J/PASP/126/616 : Variable stars in Leo I dSph (Stetson+, 2014)
J/ApJ/784/76 : RR Lyrae in ESO294-G010 and ESO410-G005 (Yang+, 2014)
J/ApJ/814/71 : Carina project IX: UBVI of Carina variables (Coppola+, 2015)
J/AcA/65/233 : OGLE Magellanic Clouds anomalous Cepheids (Soszynski+, 2015)
J/AJ/152/170 : RRLs in globulars. IV. UBVRI in Omega Cen (Braga+, 2016)
J/ApJ/829/26 : Variables in Andromeda XXV field. III. (Cusano+, 2016)
J/ApJ/833/167 : PAndAS view of Andromeda satellites. II. (Martin+, 2016)
J/MNRAS/462/4349 : Variable stars in Sculptor dSph (Martinez-Vazquez+, 2016)
J/MNRAS/455/2163 : BI LCs of DDO210 pulsating variables (Ordonez+, 2016)
J/ApJ/842/60 : Variable stars in Logal Group gal. III. (Monelli+, 2017)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- dSph Galaxy name
11- 12 I2 h RAh Hour of right ascension (J2000)
14- 15 I2 min RAm Minute of right ascension (J2000)
17- 20 F4.1 s RAs Second of right ascension (J2000)
22 A1 --- DE- Sign of declination (J2000)
23- 24 I2 deg DEd Degree of declination (J2000)
26- 27 I2 arcmin DEm Arcminute of declination (J2000)
29- 32 F4.1 arcsec DEs Arcsecond of declination (J2000)
34- 38 F5.1 mag VMag [-11.6/-7.3] Absolute V-band magnitude
40- 42 F3.1 mag e_VMag [0.2/0.4] Negative uncertainty on VMag
44- 46 F3.1 mag E_VMag [0.2/0.4] Positive uncertainty on VMag
48- 52 F5.3 mag E(B-V) [0.04/0.08] Reddening
54- 57 F4.2 --- ell [0.1/0.6] Ellipticity (ε=1-b/a)
59- 62 F4.2 --- e_ell [0.02/0.1] ell uncertainty
64- 66 I3 deg PA [30/140] Position angle
68- 69 I2 deg e_PA [1/15] PA uncertainty
71- 73 F3.1 arcmin rh [1/5.3] Half-light radius
75- 78 F4.2 arcmin e_rh [0.01/0.2] rh uncertainty
80 A1 --- u_rt [~] Uncertainty flag on rt
81- 84 F4.1 arcmin rt [4.3/22] Tidal radius
86- 88 F3.1 arcmin e_rt [0.9/1.2]? rt uncertainty
90- 93 A4 --- Ref References (1)
--------------------------------------------------------------------------------
Note (1): References as follows:
1 = Martin et al. (2016, J/ApJ/833/167),
2 = McConnachie & Irwin (2006MNRAS.365.1263M 2006MNRAS.365.1263M),
3 = Ibata et al. (2007ApJ...671.1591I 2007ApJ...671.1591I),
4 = Slater et al. (2015ApJ...806..230S 2015ApJ...806..230S), and
5 = Tollerud et al. (2013ApJ...768...50T 2013ApJ...768...50T).
--------------------------------------------------------------------------------
Byte-by-byte Description of file: a1*.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 A4 --- Cam HST camera of observation (ACS or WFC3)
6- 7 I2 h RAh Hour of Right Ascension (J2000)
9- 10 I2 min RAm Minute of Right Ascension (J2000)
12- 15 F4.1 s RAs Second of Right Ascension (J2000)
17 A1 --- DE- Sign of the Declination (J2000)
18- 19 I2 deg DEd Degree of Declination (J2000)
21- 22 I2 arcmin DEm Arcminute of Declination (J2000)
24- 27 F4.1 arcsec DEs Arcsecond of Declination (J2000)
29- 46 A18 --- File FITS image filename as it appears in the
HST archive (http://archive.stsci.edu/)
48- 57 A10 "Y/M/D" Obs.date Observation Date
59- 66 A8 "h:m:s" Obs.time UT start time
68- 72 A5 --- Filt Filter (F475W or F814W)
74- 78 I5 s Exp [987/1410] Exposure time
--------------------------------------------------------------------------------
Byte-by-byte Description of file: b2*.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- dSph Galaxy name
10 A1 --- --- [-]
11- 14 A4 --- Star Variable star name (VNNN)
16- 27 F12.6 d HJD-F475 Heliocentric Julian Date; F475W
mid-exposure: HJD-2400000
29- 34 F6.3 mag F475Wmag [22.1/26.6]? HST F475W magnitudes
36- 40 F5.3 mag e_F475Wmag [0.01/0.8]? Uncertainty in F475Wmag
42- 53 F12.6 d HJD-F814 Heliocentric Julian Date; F814W
mid-exposure: HJD-2400000
55- 60 F6.3 mag F814Wmag [21.8/28.1]? HST F814W magnitudes
62- 66 F5.3 mag e_F814Wmag [0.01/9.7]? Uncertainty in F814Wmag
--------------------------------------------------------------------------------
Byte-by-byte Description of file: c3*.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 A4 --- ID Identifier in Pritzl+ (2004, J/AJ/127/318 or
2005, J/AJ/129/2232) (1)
6- 10 F5.3 d PerP [0.2/1.7]?=9.999 Period
from Pritzl+ (2004, J/AJ/127/318 or
2005, J/AJ/129/2232)
12- 17 A6 --- dSph Galaxy name
18 A1 --- --- [-]
19- 22 A4 --- Star Variable star name in ISLAndS Galaxy (2)
24- 28 F5.3 d Per [0.2/1.1]? Period, this work (2)
30-170 A141 --- Notes Notes on cross-identification
--------------------------------------------------------------------------------
Note (1): Stars in AndII are <[PAJ2004] VNN> in Simbad whereas stars in AndI and
AndIII are <[PAJ2005] And I VNNN> and
<[PAJ2005] And III VNN> in Simbad, respectively.
Note (2): Missing values explained in Notes.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: d4*.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- dSph Galaxy name
10 A1 --- --- [-]
11- 14 A4 --- Star Variable star name in ISLAndS project (1)
16- 17 I2 h RAh Hour of Right Ascension (J2000)
19- 20 I2 min RAm Minute of Right Ascension (J2000)
22- 27 F6.3 s RAs Second of Right Ascension (J2000)
29 A1 --- DE- Sign of the Declination (J2000)
30- 31 I2 deg DEd Degree of Declination (J2000)
33- 34 I2 arcmin DEm Arcminute of Declination (J2000)
36- 40 F5.2 arcsec DEs Arcsecond of Declination (J2000)
42- 46 F5.3 d Per Current Period, days
48- 53 F6.3 mag F475Wmag [22.9/26.2] HST/Camera F475W intensity-averaged
magnitudes
55- 59 F5.3 mag F475WAmp [0.02/1.8] HST/Camera F475W amplitude
61- 66 F6.3 mag F814Wmag [22.3/25.4] HST/Camera F814W intensity-averaged
magnitudes
68- 72 F5.3 mag F814WAmp [0.04/1.1] HST/Camera F814W amplitude
74- 79 F6.3 mag Bmag [23/26.4] Converted B band intensity-averaged
magnitudes (2)
81- 85 F5.3 mag BAmp [0.1/2] Converted B band amplitude (2)
87- 92 F6.3 mag Vmag [22.7/26] Converted V band intensity-averaged
magnitudes (2)
94- 98 F5.3 mag VAmp [0.09/1.6] Converted V band amplitude (2)
100-105 F6.3 mag Icmag [22.3/25.4] Converted Ic band intensity-averaged
magnitudes (2)
107-111 F5.3 mag IcAmp [0.04/1.1] Converted Ic band amplitude
113-119 A7 --- Type Variable Type (3)
121-124 A4 --- Cam Camera used for F475W, F814W data (ACS or WFC3)
--------------------------------------------------------------------------------
Note (1): Stars are <[MMB2017] {dSph}-{Star}> in Simbad.
Note (2): HST F475W and F814W VEGAMAGs are transformed to Johnson-Cousins
B,V,Ic using the equations obtained
by Bernard+ (2009, J/ApJ/699/1742).
Both B and V are transformed from F475W.
Note (3): Types are:
EB = eclipsing binary (1 objects in AndI; 2 objects in AndII)
GSS RRL = 5 objects in AndI
M31 RRL = 1 object in AndIII; 1 object in AndXVI
RRL? = 2 objects in AndXXVIII
RRab = 229 objects in AndI; 187 objects in AndII; 84 objects in AndIII;
80 objects in AndXV; 3 objects in AndXVI; 35 objects in AndXXVIII
RRc = 48 objects in AndI; 48 objects in AndII; 15 objects in AndIII;
24 objects in AndXV; 5 objects in AndXVI; 35 objects in AndXXVIII
RRd = 19 objects in AndI; 16 objects in AndII; 12 objects in AndIII;
13 objects in AndXV; 15 objects in AndXXVIII
AC = Anomalous Cepheids (4 objects in AndII; 4 objects in AndIII;
4 objects in AndXV; 3 objects in AndXXVIII)
--------------------------------------------------------------------------------
History:
From electronic version of the journal
References:
Monelli et al. Paper I. 2016ApJ...819..147M 2016ApJ...819..147M
Skillman et al. Paper II. 2017ApJ...837..102S 2017ApJ...837..102S
Martinez-Vazquez et al. Paper III. 2017ApJ...850..137M 2017ApJ...850..137M This catalog
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 29-Jun-2018