J/ApJS/136/631 IUE absorption toward 164 early-type stars (Savage+, 2001)
IUE absorption-line observations of the moderately and highly ionized
interstellar medium toward 164 early-type stars.
Savage B.D., Meade M.R., Sembach K.R.
<Astrophys. J. Suppl. Ser. 136, 631 (2001)>
=2001ApJS..136..631S 2001ApJS..136..631S
ADC_Keywords: Stars, early-type ; Interstellar medium ; Radial velocities ;
Rotational velocities ; Photometry, UBV ; Equivalent widths ;
Spectra, ultraviolet
Keywords: Galaxy: halo - ISM: abundances - ISM: clouds - ultraviolet: ISM
Abstract:
We present measurements of Galactic interstellar AlIII, SiIV, and
CIV absorption recorded in high-resolution archival ultraviolet spectra
of 164 hot early-type stars observed by the International Ultraviolet
Explorer (IUE) satellite. The objects studied were drawn from the list
of hot stars scheduled to be observed with the Far Ultraviolet
Spectroscopic Explorer (FUSE) satellite as part of observing programs
designed to investigate absorption by OVI in the Galactic disk and
halo. Multiple IUE echelle-mode integrations have been combined to
produce a single ultraviolet (1150-1900Å) spectrum of each star with
a spectral resolution of ∼25km/s (FWHM). Selected absorption-line
profiles are presented for each star along with plots of the apparent
column density per unit velocity for each line of the AlIII, SiIV,
and CIV doublets. We report absorption-line equivalent widths,
absorption velocities, and integrated column densities based on the
apparent optical depth method of examining interstellar absorption
lines. We also determine column densities and Doppler parameters from
single-component curve-of-growth analyses. The scientific analysis of
these observations will be undertaken after the FUSE satellite
produces similar measurements for absorption by interstellar OIV,
FeIII, SIII, and other ions.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 83 186 Program Stars
table3.dat 157 328 Equivalent widths, velocities, line widths &
apparent column densities
table4.dat 120 328 Final column densities
refs.dat 69 92 References
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See also:
II/114 : UV Interstellar Extinction (Savage+ 1985)
J/ApJS/93/211 : IUE survey of H I Lyα absorption. I. (Diplas+ 1994)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Object name
13 A1 --- f_Name [c] Flag on Name (1)
15- 25 A11 --- SpType The MK spectral type
27- 32 F6.2 deg GLON Galactic longitude
34- 39 F6.2 deg GLAT Galactic latitude
41- 45 F5.2 mag Vmag ? The V band magnitude
47- 50 F4.2 mag E(B-V) ? The (B-V) reddening excess
52- 56 F5.2 [cm-2] logN ? Log of the hydrogen column density
58- 62 I5 pc Dist ? Distance
64- 68 I5 pc Zdist ? Galactic plane scale height
70- 72 I3 km/s vsin(i) ? The vsin(i) rotational velocity
74- 77 I4 km/s VRad ? The LSR radial velocity
79- 80 I2 --- r_SpType The SpType reference in refs.dat
82- 83 I2 --- r_Vmag ? The Vmag and Bmag reference in refs.dat
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Note (1): Various measurement problems caused by stellar blending or low
signal-to-noise ratio data were judged to be severe enough we did
not attempt ISM absorption line measurements. However, the spectral
absorption line velocity plots are shown in Figure 2. In some of
these cases it may be possible to determine useful upper limits if
the stellar blending can be better understood.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Object name
13 A1 --- Line [sw] strong or weak doublet line
15- 17 I3 10-13m EqWAlIII ? Equivalent width of Al III
(1854.72, 1862.79Å) in milli-Angstroms
19- 20 I2 10-13m e_EqWAlIII ? The 1σ error in EqWAlIII (2)
22 A1 --- f_EqWAlIII [nbs] Flag on EqWAlIII (3)
24- 28 F5.1 km/s VelAlIII ? Average LSR velocity of Al III
30- 32 F3.1 km/s e_VelAlIII ? Uncertainty in VelAlIII
34- 37 F4.1 km/s sigAlIII ? Velocity dispersion in Al III (4)
39- 42 F4.1 km/s e_sigAlIII ? Uncertainty in sigAlIII
44 A1 --- l_NAlIII Limit flag on NAlIII
45- 49 F5.2 [cm-2] NAlIII ? Log of the Al III apparent column density
51- 54 F4.2 [cm-2] e_NAlIII ? Uncertainty in NAlIII
56- 58 I3 10-13m EqWSiIV ? Equivalent width of Si IV
(1393.76, 1402.77Å) in milli-Angstroms
60- 61 I2 10-13m e_EqWSiIV ? The 1σ error in EqWSiIV (2)
63 A1 --- f_EqWSiIV [nb] Flag on EqSiIV (3)
65- 69 F5.1 km/s VelSiIV ? Average LSR velocity of Si IV
71- 74 F4.1 km/s e_VelSiIV ? Uncertainty in VelSiIV
76- 79 F4.1 km/s sigSiIV ? Velocity dispersion in Si IV (4)
81- 84 F4.1 km/s e_sigSiIV ? Uncertainty in sigSiIV
86 A1 --- l_NSiIV Limit flag on NSiIV
87- 91 F5.2 [cm-2] NSiIV ? Log of the Si IV apparent column density
93- 96 F4.2 [cm-2] e_NSiIV ? Uncertainty in NSiIV
98-100 I3 10-13m EqWCIV ? Equivalent width of C IV
(1548.20, 1550.77Å) in milli-Angstroms
102-103 I2 10-13m e_EqWCIV ? The 1σ error in EqWCIV (2)
105 A1 --- f_EqWCIV [nb] Flag on EqCIV (3)
107-111 F5.1 km/s VelCIV ? Average LSR velocity of C IV
113-116 F4.1 km/s e_VelCIV ? Uncertainty in VelCIV
118-121 F4.1 km/s sigCIV ? Velocity dispersion in C IV (4)
123-126 F4.1 km/s e_sigCIV ? Uncertainty in sigCIV
128 A1 --- l_NCIV Limit flag on NCIV
129-133 F5.2 [cm-2] NCIV ? Log of the C IV apparent column density
135-138 F4.2 [cm-2] e_NCIV ? Uncertainty in NCIV
140-144 F5.1 km/s VelSiII ? Average LSR velocity of Si II (1808.01Å)
146-148 F3.1 km/s e_VelSiII ? Uncertainty in VelSiII
150-153 F4.1 km/s sigSiII ? Velocity dispersion in Si II (4)
155-157 F3.1 km/s e_sigSiII ? Uncertainty in sigSiII
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Note (2): Includes statistical noise in the data and continuum placement
uncertainties (see Sembach & Savage, 1992ApJS...83..147S 1992ApJS...83..147S).
Note (3): Flag as follows:
n = signal-to-noise is low
b = severe stellar blending
s = saturation of the IUE detector
Note (4): Measure the combined effects of the multiple component nature of
the absorption, thermal line broadening, and instrumental blurring.
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Object name
13- 15 A3 --- Method Method used to determine column densities (1)
17 A1 --- l_NAlIII Limit flag on NAlIII
18- 22 F5.2 [cm-2] NAlIII ? Log of the Al III (1854.72, 1862.79Å)
line of sight column density in atoms/cm2
23- 24 A2 --- u_NAlIII [: ] Uncertainty flag on NAlIII (2)
26- 29 F4.2 [cm-2] E_NAlIII ? Upper 1σ error in NAlIII (3)
31- 34 F4.2 [cm-2] e_NAlIII ? Lower 1σ error in NAlIII
35 A1 --- ueNAlIII [:] Indicates an uncertain upper and lower
error in NAlIII
37- 40 F4.1 km/s bAlIII ? Al III Doppler velocity spread parameter
42- 45 F4.1 km/s E_bAlIII ? Upper 1σ error in bAlIII (4)
47- 50 F4.1 km/s e_bAlIII ? Lower 1σ error in bAlIII
52 A1 --- l_NSiIV Limit flag on NSiIV
53- 57 F5.2 [cm-2] NSiIV ? Log of the Si IV (1393.76, 1402.77Å)
line of sight column density in atoms/cm2
58- 59 A2 --- u_NSiIV [: ] Uncertainty flag on NSiIV (2)
61- 64 F4.2 [cm-2] E_NSiIV ? Upper 1σ error in NSiIV (3)
66- 69 F4.2 [cm-2] e_NSiIV ? Lower 1σ error in NSiIV
70 A1 --- ueNSiIV [:] Indicates an uncertain upper and lower
error in NSiIV
72- 75 F4.1 km/s bSiIV ? Si IV Doppler velocity spread parameter
77- 80 F4.1 km/s E_bSiIV ? Upper 1σ error in bSiIV (4)
82- 85 F4.1 km/s e_bSiIV ? Lower 1σ error in bSiIV
87 A1 --- l_NCIV Limit flag on NCIV
88- 92 F5.2 [cm-2] NCIV ? Log of the C IV (1548.20, 1550.77Å)
line of sight column density in atoms/cm2
93- 94 A2 --- u_NCIV [: ] Uncertainty flag on NCIV (2)
96- 99 F4.2 [cm-2] E_NCIV ? Upper 1σ error in NCIV (3)
101-104 F4.2 [cm-2] e_NCIV ? Lower 1σ error in NCIV
105 A1 --- ueNCIV [:] Indicates an uncertain upper and lower
error in NCIV
107-110 F4.1 km/s bCIV ? C IV Doppler velocity spread parameter
112-115 F4.1 km/s E_bCIV ? Upper 1σ error in bCIV (4)
117-120 F4.1 km/s e_bCIV ? Lower 1σ error in bCIV
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Note (1): Method as follows:
COG = Curve-of-growth
AOD = apparent optical depth
Note (2): The uncertainty flag means:
: = uncertain column density
:: = inconsistent column density (see text)
Note (3): NULL values indicate that the observations imply strong line
saturation and the upper bound is not well determined.
Note (4): NULL values indicate that the measurements are consistent with the
absorption being on the linear part of the COG and an upper limit
is not well determined.
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Ref Reference number
4- 22 A19 --- BibCode BiCode
24- 48 A25 --- Aut Author's name
57- 69 A13 --- Com Comments
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Bauer [CDS] 14-Jan-2002