J/MNRAS/357/645 LMC far-UV HST observations (Almoznino+, 2005)
The deepest Hubble Space Telescope far-ultraviolet observations in the
Large Magellanic Cloud.
Almoznino E., Brosch N., Shara M., Zurek D.
<Mon. Not. R. Astron. Soc., 357, 645-655 (2005)>
=2005MNRAS.357..645A 2005MNRAS.357..645A
ADC_Keywords: Magellanic Clouds ; Ultraviolet ; Photometry, CCD
Keywords: stars: formation - galaxies: individual: Large Magellanic Cloud -
galaxies: irregular - galaxies: stellar content
Abstract:
We present a new analysis of the deepest pure-ultraviolet (UV)
observations with the highest angular resolution ever performed. A set
of 12 exposures with the Hubble Space Telescope (HST) WFPC2 and F160BW
filter obtained in parallel observing mode, which cover ∼12arcmin2 in
the Large Magellanic Cloud (LMC), north of the bar and in the 'general
field' region of the LMC, contain stars with far-UV monochromatic
magnitudes as faint as 22mag. The 198 detected UV sources represent
an accumulated exposure of 2x104s and reveal stars as faint as
mUV≃20mag. We combine these observations with deep UBVI
charge-coupled device (CCD) imaging of the same region reaching as
faint as V≃26mag, and reselect probable optical counterparts for the
UV sources. After a two-stage search-and-analysis process, we detect
robust counterparts for 129 stars. These are mostly upper
main-sequence stars, from early B to early A spectral classes, with
several F stars. We point out the lack of blue supergiants, which
could have been easily detected in our survey. We measure a foreground
extinction E(B-V)≃0.08mag by Galactic dust and a surface density of
star formation rate twice the average Galactic value. These
observations indicate that relatively recent star formation took place
even off the bar of the LMC.
Description:
New optical observations of a small fraction of the LMC, including the
area studied with the HST, were performed by MS using the CTIO 4-m
Victor Blanco Telescope with the Mosaic II CCD imager.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 275 129 FUV (160nm) stars in the HST LMC field
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See also:
J/AJ/117/206 : LMC far-ultraviolet imaging (Brosch+, 1999)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- [BSM99] UV source number, from Brosch et al.,
1999, Cat. J/AJ/117/206
4 A1 --- m_[BSM99] Multiplicity (for source #37) (1)
5- 6 I2 --- nObs Number of observations
8- 9 I2 h RAh HST right ascension (J2000.0)
10 A1 --- --- [:]
11- 12 I2 min RAm HST right ascension (J2000.0)
13 A1 --- --- [:]
14- 18 F5.2 s RAs HST right ascension (J2000.0)
20 A1 --- DE- HST declination sign (J2000.0)
21- 22 I2 deg DEd HST declination (J2000.0)
23 A1 --- --- [:]
24- 25 I2 arcmin DEm HST declination sign (J2000.0)
26 A1 --- --- [:]
27- 31 F5.2 arcsec DEs HST declination sign (J2000.0)
33- 34 I2 h RACh Corrected right ascension (J2000.0)
35 A1 --- --- [:]
36- 37 I2 min RACm Corrected right ascension (J2000.0)
38 A1 --- --- [:]
39- 44 F6.3 s RACs Corrected right ascension (J2000.0)
48 A1 --- DEC- Corrected declination sign (J2000.0)
49- 50 I2 deg DECd Corrected declination (J2000.0)
51 A1 --- --- [:]
52- 53 I2 arcmin DECm Corrected declination sign (J2000.0)
54 A1 --- --- [:]
55- 59 F5.2 arcsec DECs Corrected declination sign (J2000.0)
61- 65 F5.2 mag UVmag Far UV (F160BW, 160nm) magnitude
67- 70 F4.2 mag e_UVmag rms uncertainty on UVmag
72- 77 I6 --- [ABS2005] LMC optical counterpart number
79- 86 F8.3 pix Xpos X position
88- 94 F7.3 pix Ypos Y position
96- 97 I2 h RAOh CCD right ascension (J2000.0)
98 A1 --- --- [:]
99-100 I2 min RAOm CCD right ascension (J2000.0)
101 A1 --- --- [:]
102-106 F5.2 s RAOs CCD right ascension (J2000.0)
108 A1 --- DEO- CCD declination sign (J2000.0)
109-110 I2 deg DEOd CCD declination (J2000.0)
111 A1 --- --- [:]
112-113 I2 arcmin DEOm CCD declination sign (J2000.0)
114 A1 --- --- [:]
115-119 F5.2 arcsec DEOs CCD declination sign (J2000.0)
121-126 F6.3 mag Imag I magnitude
128-132 F5.3 mag e_Imag rms uncertainty on Imag
134 I1 --- o_Imag [3] Number of observations in I band
136-141 F6.3 mag Vmag V magnitude
143-147 F5.3 mag e_Vmag rms uncertainty on Vmag
149 I1 --- o_Vmag [3] Number of observations in V band
151-156 F6.3 mag Bmag B magnitude
158-162 F5.3 mag e_Bmag rms uncertainty on Bmag
164 I1 --- o_Bmag [3] Number of observations in B band
166-171 F6.3 mag Umag U magnitude
173-177 F5.3 mag e_Umag rms uncertainty on Umag
179 I1 --- o_Umag [3] Number of observations in U band
181-186 F6.3 mag V-I V-I colour index
188-192 F5.3 mag e_V-I rms uncertainty on V-I
194-199 F6.3 mag B-V B-V colour index
201-205 F5.3 mag e_B-V rms uncertainty on B-V
207-212 F6.3 mag U-B U-B colour index
214-218 F5.3 mag e_U-B rms uncertainty on U-B
220-225 F6.3 mag U-V U-V colour index
227-231 F5.3 mag e_U-V rms uncertainty on U-V
233-236 F4.2 arcsec Dist Distance between UV and optical source
238-243 F6.3 mag UV-I UV-I colour index
245-249 F5.3 mag e_UV-I rms uncertainty on UV-I
251-256 F6.3 mag UV-U UV-U colour index
258-262 F5.3 mag e_UV-U rms uncertainty on UV-U
264-269 F6.3 mag UV-V UV-V colour index
271-275 F5.3 mag e_UV-V rms uncertainty on UV-V
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Note (1): in the original table, the source #37 appeared twice.
The correct suffix was added at CDS in May 2007, according
to the original list of Brosch et al. (1999AJ....117..206B 1999AJ....117..206B)
History:
* 07-Feb-2006: From electronic version of the journal
* 31-May-2007: Suffix added in table2 for source #37
(End) Patricia Vannier [CDS] 07-Feb-2006