J/MNRAS/461/3702 gi photometry of Bootes I (Roderick+, 2016)
Extended stellar substructure surrounding the Bootes I dwarf spheroidal galaxy.
Roderick T.A., Mackey A.D., Jerjen H., Da Costa G.S.
<Mon. Not. R. Astron. Soc., 461, 3702-3713 (2016)>
=2016MNRAS.461.3702R 2016MNRAS.461.3702R (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, nearby ; Photometry, SDSS
Keywords: galaxies: dwarf - galaxies: evolution -
galaxies: fundamental parameters - galaxies: individual: Bootes I
Abstract:
We present deep stellar photometry of the Bootes I dwarf spheroidal
galaxy in g- and i-band filters, taken with the Dark Energy Camera at
Cerro Tololo in Chile. Our analysis reveals a large, extended region
of stellar substructure surrounding the dwarf, as well as a distinct
overdensity encroaching on its tidal radius. A radial profile of the
Bootes I stellar distribution shows a break radius indicating the
presence of extra-tidal stars. These observations strongly suggest
that Bootes I is experiencing tidal disruption, although not as
extreme as that exhibited by the Hercules dwarf spheroidal. Combined
with revised velocity dispersion measurements from the literature, we
see evidence suggesting the need to review previous theoretical models
of the Bootes I dwarf spheroidal galaxy.
Description:
Observations were carried out as part of observing proposal 2013A-0617
(PI: D. Mackey), on 2013 February 15, using DECam on the 4m Blanco
telescope at Cerro Tololo in Chile. DECam is comprised of a hexagonal
mosaic of 62 2Kx4K CCDs, each with a pixel scale of 0.27arcsec/pix,
creating a total field of view of 3deg2.
The data set consists of a single pointing taken in the direction of
Bootes I (see Fig. 1), in g- and i-band filters. A total of 3x300s
exposures were taken in each filter, providing a total integration
time of 900s each, with an average seeing of 1.30 and 1.14-arcsec in
g and i, respectively.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
catalog.dat 39 2677 Catalog
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See also:
J/AJ/136/2321 : Washington photometry of Bootes I stars (Hughes+, 2008)
J/ApJ/736/146 : Radial velocities of stars in Bootes I (Koposov+, 2011)
J/ApJ/763/61 : Abundances of 7 red giant members of BootesI (Gilmore+ 2013)
J/MNRAS/439/788 : Stromgren and Washington photometry in Boo I (Hughes+, 2014)
J/MNRAS/450/1477 : VLA 352MHz image of the Bootes field. I. (Coppejans+, 2015)
Byte-by-byte Description of file: catalog.dat
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Bytes Format Units Label Explanations
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1- 8 F8.4 deg RAdeg Rigth ascension (J2000)
10- 16 F7.4 deg DEdeg Declination (J2000)
18- 24 F7.4 mag gmag SDSS g magnitude
26- 32 F7.4 mag imag SDSS i magnitude
34- 39 E6.2 --- Weight [0/1]?=- Weight (1)
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Note (1): each star in the catalogue was assigned a weight between 0 and 1 based
on the mask, providing a flexible means of selecting stars consistent with
membership of Bootes I.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 11-Dec-2017