J/ApJ/702/940 Radio and UV spectra of HVC toward the MC (Lehner+, 2009)
Properties and origin of the high-velocity gas toward the Large Magellanic
Cloud.
Lehner N., Staveley-Smith L., Howk J.C.
<Astrophys. J., 702, 940-954 (2009)>
=2009ApJ...702..940L 2009ApJ...702..940L
ADC_Keywords: Stars, early-type ; Magellanic Clouds ; Spectra, ultraviolet ;
Radio lines
Keywords: galaxies: halos - galaxies: interactions - galaxies: kinematics and
dynamics - galaxies: structure - Magellanic Clouds
Abstract:
In the spectra of 139 early-type Large Magellanic Cloud (LMC) stars
observed with Far Ultraviolet Spectroscopic Explorer and with deep
radio Parkes HI 21cm observations along with those stars, we search
for and analyze the absorption and emission from high-velocity gas at
+90≤νLSR≤+175km/s. The HI column density of the high-velocity
clouds (HVCs) along these sightlines ranges from <1018.4 to
1019.2cm-2. The incidence of the HVC metal absorption is 70%,
significantly higher than the HI emission occurrence of 32%. We find
that the mean metallicity of the HVC is [OI/HI]=-0.51±0.120.16.
This is the first example of a large (>106M☉) HVC complex that
is linked to stellar feedback occurring in a dwarf spiral galaxy.
Description:
We retrieved fully calibrated spectra from the FUSE Magellanic Clouds
Legacy Project archive at the Multimission Archive at STScI
(http://archive.stsci.edu/prepds/fuse_mc/). The spectra of 10 stars in
our sample were obtained with both FUSE and HST/STIS E140M.
Two data sets were used for the HI 21cm data: the LMC HI survey
campaign undertaken by Staveley-Smith et al. (2003MNRAS.339...87S 2003MNRAS.339...87S)
using the Parkes 21cm multi-beam receiver. We also systematically used
the more recent survey undertaken by McClure-Griffiths et al.
(2009ApJS..181..398M 2009ApJS..181..398M), the Parkes Galactic All-Sky Survey (GASS).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 140 139 Summary of the measurements for the
high-velocity clouds (HVCs) toward the LMC
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See also:
B/hst : HST Archived Exposures Catalog (STScI, 2007)
J/ApJS/171/419 : Catalog of LMC HI clouds (Kim+, 2007)
J/ApJ/623/181 : Compact high-velocity cloud photometry catalog (Siegel+,
2005)
J/MNRAS/357/645 : LMC far-UV HST observations (Almoznino+, 2005)
J/A+A/391/159 : A search for Compact High-Velocity Clouds (De Heij+, 2002)
J/AJ/123/873 : HIPASS high-velocity clouds (Putman+, 2002)
J/ApJS/140/331 : High-velocity HI observations at 21cm (Lockman+, 2002)
J/ApJS/136/463 : Distances and metallicities of HVCs and IVCs (Wakker, 2001)
J/AJ/117/206 : LMC far-ultraviolet imaging (Brosch+, 1999)
J/ApJS/79/77 : Bell Lab. H I Survey - High Velocity Clouds (Stark+ 1992)
http://archive.stsci.edu/prepds/fuse_mc/ : FUSE Magellanic Clouds Legacy
Project page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- Name Star name (1)
13 A1 --- f_Name [a] spectra from HST/STIS E140M and FUSE
15- 20 F6.4 h RAhour Right ascension in decimal hour (J2000)
22- 29 F8.4 deg DEdeg Declination in decimal degree (J2000)
31- 35 F5.1 km/s nuOI ? OI FUSE velocity (ν) (4)(3)
37- 39 F3.1 km/s e_nuOI ? nuOI uncertainty
41 A1 --- l_logNOI Limit flag on logNOI
42- 46 F5.2 [cm-2] logNOI ? OIλ1039 column density (N(OI)) (5)
48- 51 F4.2 [cm-2] e_logNOI ? Lower limit uncertainty in logNOI
53- 56 F4.2 [cm-2] E_logNOI ? Upper limit uncertainty in logNOI
58- 62 F5.1 km/s nuFeII ? FeII FUSE velocity (ν) (4)(3)
64- 66 F3.1 km/s e_nuFeII ? nuFeII uncertainty
68 A1 --- l_logNFeII Limit flag on logNFeII
69- 73 F5.2 [cm-2] logNFeII ? FeII 1144 column density (N(FeII)) (5)
75- 78 F4.2 [cm-2] e_logNFeII ? Lower limit uncertainty in logNFeII
80- 83 F4.2 [cm-2] E_logNFeII ? Upper limit uncertainty in logNFeII
85- 89 F5.1 km/s nuHI ? HI velocity (ν) (4)
91- 94 F4.1 km/s e_nuHI ? nuHI uncertainty
96 A1 --- l_logNHI Limit flag on logNHI
97-101 F5.2 [cm-2] logNHI ? HI column density (N(HI))
103-106 F4.2 [cm-2] e_logNHI ? Uncertainty in logNHI
108 A1 --- l_[FeII/OI] Limit flag on [FeII/OI]
109-113 F5.2 [-] [FeII/OI] ? Ratio [FeII/OI] corrected for the solar
oxygen abundance
115-118 F4.2 [-] e_[FeII/OI] ? Lower limit uncertainty in [FeII/OI]
120-123 F4.2 [-] E_[FeII/OI] ? Upper limit uncertainty in [FeII/OI]
125 A1 --- l_[OI/HI] Limit flag on [OI/HI]
126-130 F5.2 [-] [OI/HI] ? Ratio [OI/HI] corrected for the solar
oxygen abundance (6)
132-135 F4.2 [-] e_[OI/HI] ? Lower limit uncertainty in [OI/HI]
137-140 F4.2 [-] E_[OI/HI] ? Upper limit uncertainty in [OI/HI]
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Note (1): HV2243 is very likely a misprint for HV2543.
Note (3): The FUSE velocities (OI and FeII) have an additional systematic
error of about 5-10km/s.
Note (4): The values of the velocity, ν, is obtained from
ν=∫νNa(ν)dν/Na (see Sembach & Savage
1992ApJS...83..147S 1992ApJS...83..147S). See section 2.2.3 for further details.
Note (5): Measurements and limits on N(OI) and N(FeII) are primarily based
on the OIλ1039 and FeIIλ1144 lines, except for Sk-69
246, where OIλ1302 and FeIIλ1608 only are used as the
weaker transitions are not detected.
Note (6): For [O/H], there is an additional ±0.08dex "beam" error (see
Section 2.4 for more details). For the limits on the [O/H], the errors
on N(OI) or N(HI) were taken into account, i.e., the upper limits are
quoted as the limit +1σ (statistical uncertainty). The adopted
solar references are [O/H]☉=-3.27 and [Fe/O]☉=-1.26 from
Lodders et al. (2009LanB...4B...44L 2009LanB...4B...44L).
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History:
From electronic version of the journal
(End) Emmanuelle Perret [CDS] 30-Sep-2011