J/MNRAS/451/3219 CT1 photometry for 11 star fields in the SMC (Piatti, 2015)
The age-metallicity relationship in the Small Magellanic Cloud periphery.
Piatti A.E.
<Mon. Not. R. Astron. Soc., 451, 3219-3227 (2015)>
=2015MNRAS.451.3219P 2015MNRAS.451.3219P (SIMBAD/NED BibCode)
ADC_Keywords: Magellanic Clouds ; Populations, stellar ; Photometry, CMT1T2V
Keywords: techniques: photometric - galaxies: individual: SMC -
Magellanic Clouds
Abstract:
We present results from Washington CT1 photometry for 11 star fields
located in the western outskirts of the Small Magellanic Cloud (SMC),
which cover angular distances to its centre from 2° up to 13°
(∼2.2-13.8 kpc). The colour-magnitude diagrams, cleaned from the
unavoidable Milky Way (MW) and background galaxy signatures, reveal that
the most distant dominant main-sequence (MS) stellar populations from
the SMC centre are located at an angular distance of ∼5.7° (6.1 kpc);
no sign of farther clear SMC MS is visible other than the residuals from
the MW/background field contamination. The derived ages and metallicities
for the dominant stellar populations of the western SMC periphery show
a constant metallicity level ([Fe/H]=-1.0 dex) and an approximately
constant age value (∼7-8 Gyr). Their age-metallicity relationship (AMR)
do not clearly differ from the most comprehensive AMRs derived for almost
the entire SMC main body. Finally, the range of ages of the dominant
stellar populations in the western SMC periphery confirms that the major
stellar mass formation activity at the very early galaxy epoch peaked
∼7-8 Gyr ago.
Description:
we performed a search within the National Optical Astronomy
Observatory (NOAO) Science Data Management (SDM) Archives
(http://www.noao.edu/sdm/archives.php) seeking for Washington
photometric data towards the SMC periphery. As a result, we found
images obtained at the Cerro-Tololo Inter-American Observatory (CTIO)
4 m Blanco telescope with the MOSAIC II camera (36x36 arcmin2 field
with a 8kx8k CCD detector array, scale 0.274 arcsec/pixel) covering
11 fields in the SMC outskirts for a total area of ∼4.0 deg2
(programme CTIO 2006B-0013, PI: Saha).
Objects:
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RA (ICRS) DE Designation(s)
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00 52 38.0 -72 48 01 SMC = NAME Small Magellanic Cloud
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tab2f1.dat 59 6468 CT1 data of stars in Field 1
tab2f2.dat 59 10536 CT1 data of stars in Field 2
tab2f3.dat 59 10383 CT1 data of stars in Field 3
tab2f4.dat 59 8364 CT1 data of stars in Field 4
tab2f5.dat 59 8167 CT1 data of stars in Field 5
tab2f6.dat 59 8298 CT1 data of stars in Field 6
tab2f7.dat 59 10159 CT1 data of stars in Field 7
tab2f8.dat 59 14904 CT1 data of stars in Field 8
tab2f9.dat 59 19523 CT1 data of stars in Field 9
tab2f10.dat 59 10789 CT1 data of stars in Field 10
tab2f11.dat 59 75988 CT1 data of stars in Field 11
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See also:
J/MNRAS/358/1215 : CT1 photometry of 10 SMC clusters (Piatti+, 2005)
J/A+A/452/179 : Ages of SMC young clusters and field stars (Chiosi+, 2006)
J/MNRAS/377/300 : CT1 photometry in 6 SMC star clusters (Piatti+, 2007)
J/MNRAS/381/L84 : CT1 photometry of 3 SMC old clusters (Piatti+, 2007)
J/MNRAS/382/1203 : CT1 photometry of 5 SMC star clusters (Piatti+, 2007)
J/MNRAS/389/429 : CT1 photometry of 7 young SMC star clusters (Piatti+, 2008)
J/A+A/591/A11 : SMC BV photometry of 9 star cluster fields (Dias+, 2016)
Byte-by-byte Description of file: tab2f[123456789].dat tab2f1[01].dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- Star [1/75988] Star running number
7- 8 I2 h RAh Hour of Right Ascension (J2000)
10- 11 I2 min RAm Minute of Right Ascension (J2000)
13- 18 F6.3 s RAs Second of Right Ascension (J2000)
20 A1 --- DE- Sign of the Declination (J2000)
21- 22 I2 deg DEd Degree of Declination (J2000)
24- 25 I2 arcmin DEm Arcminute of Declination (J2000)
27- 31 F5.2 arcsec DEs Arcsecond of Declination (J2000)
33- 38 F6.3 mag T1mag [10.344/25.322] Averaged T1 magnitude
40- 44 F5.3 mag e_T1mag [0.001/0.542] Uncertainty in T1mag
46- 51 F6.3 mag C-T1 [-6.193/7.275] C-T1 colour
53- 57 F5.3 mag e_C-T1 [0.002/0.755] Uncertainty in C-T1
59 I1 --- n [1/6] Number of measurements in the C and T1
filters
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History:
From electronic version of the journal
(End) Tiphaine Pouvreau [CDS] 02-Dec-2019