J/ApJ/727/46 Highly ionized plasmas in the Milky Way (Lehner+, 2011)
Fundamental properties of the highly ionized plasmas in the Milky Way.
Lehner N., Zech W.F., Howk J.C., Savage B.D.
<Astrophys. J., 727, 46 (2011)>
=2011ApJ...727...46L 2011ApJ...727...46L
ADC_Keywords: Stars, OB ; Ultraviolet ; Milky Way ; Interstellar medium
Keywords: Galaxy: disk - ISM: clouds - ISM: structure - ultraviolet: ISM
Abstract:
The cooling transition temperature gas in the interstellar medium
(ISM), traced by the high ions, SiIV, CIV, NV, and OVI, helps to
constrain the flow of energy from the hot ISM with T>106K to the
warm ISM with T<2x104K. We investigate the properties of this gas
along the lines of sight to 38 stars in the Milky Way disk using
1.5-2.7km/s resolution spectra of SiIV, CIV, and NV absorption from
the Space Telescope Imaging Spectrograph, and 15km/s resolution
spectra of OVI absorption from the Far Ultraviolet Spectroscopic
Explorer. The absorption by SiIV and CIV exhibits broad and narrow
components while only broad components are seen in NV and OVI. The
narrow components imply gas with T<7x104K and trace two distinct
types of gas.
Description:
We searched the multi-mission archive at Space Telescope (MAST) for
all the OB-type stars that were observed with HST/STIS using the E140H
setting, which provides the highest resolution (R>114000) and the
wavelength coverage for CIV, SiIV, and NV as well as other species. We
also search the FUSE (which provides the wavelength coverage of OVI)
archive at MAST.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 68 117 Data summary
table2.dat 130 38 Sight line overview
table3.dat 73 258 Average LSR velocities and apparent column densities
table4.dat 134 38 Adopted apparent column densities and average
densities
table5.dat 180 38 Ionic ratios from the total apparent column densities
and apparent column density profiles
table6.dat 60 349 Results from the profile fits
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See also:
V/116 : Galactic O star catalog (Maiz-Apellaniz+, 2004)
J/ApJ/702/1472 : Column densities for HI, AlIII, SiIV, CIV, OVI (Savage+, 2009)
J/ApJS/176/59 : FUSE survey of OVI in the disk of the Milky Way (Bowen+, 2008)
J/ApJ/647/312 : FUSE survey of OVI in the Milky Way (Otte+, 2006)
J/ApJS/136/631 : IUE absorption toward 164 early-type stars (Savage+, 2001)
J/AJ/117/354 : OB associations from Hipparcos (de Zeeuw+, 1999)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name Star identification
12- 13 I2 --- Seq Star identification number
15- 23 A9 --- Dataset Dataset identification
25- 38 A14 --- PID PI/Proposal identification
40- 43 I4 s Exp Exposure time
45- 49 A5 --- Grat Grating used
51- 54 I4 0.1nm lam0 [1141/1774] Wavelength range: lower bound
55 A1 --- --- [-]
56- 59 I4 0.1nm lam1 [1335/2046] Wavelength range: upper bound
61- 68 A8 --- Aper Aperture used
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Seq Running sequence number
4- 13 A10 --- Name Star identification
15- 25 A11 --- SpT MK spectral type
27- 28 I2 --- r_SpT Spectral type reference (1)
30- 35 F6.2 deg GLON Galactic longitude
37- 42 F6.2 deg GLAT Galactic latitude
44- 48 F5.2 mag Vmag V-band magnitude
50- 52 F3.1 kpc Dist Distance (d) from Bowen et al. (2008,
Cat. J/ApJS/176/59) (2)
54- 57 F4.1 kpc Z z-height
59- 63 F5.1 km/s Vc Velocity correction (vc) (3)
65- 68 I4 km/s V* ? Radial stellar velocity in the LSR frame (4)
70 I1 --- R Parameter R following Bowen et al. (2008,
Cat. J/ApJS/176/59) (5)
72-130 A59 --- Comm Physical region along the line of sight (6)
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Note (1): Spectral type/luminosity class references as follows:
1 = Burgh et al. 2007ApJ...658..446B 2007ApJ...658..446B;
2 = Hiltner et al. 1969ApJ...157..313H 1969ApJ...157..313H;
3 = Houk N. 1982mcts.book.....H 1982mcts.book.....H;
4 = Houk & Cowley 1975mcts.book.....H 1975mcts.book.....H;
6 = Belczynski & Ziolkowski 2009ApJ...707..870B 2009ApJ...707..870B;
7 = Lyubimkov et al. 2002MNRAS.333....9L 2002MNRAS.333....9L;
8 = Maiz-Apellaniz et al. 2004, Cat. V/116;
9 = Mathys G. 1988A&AS...76..427M 1988A&AS...76..427M
10 = Savage et al. 2001, Cat. J/ApJS/136/631;
11 = Walborn N.R. 1972AJ.....77..312W 1972AJ.....77..312W;
Note (2): Or, if the star is not in Bowen et al., we calculated d following
their method.
Note (3): vc is the velocity correction to move the velocities from the
heliocentric frame to the LSR frame (vLSR=vhelio+vc)
Note (4): v* is the radial stellar velocity in the LSR frame
(heliocentric velocities are taken from the Simbad database).
Note (5): Following Bowen et al. (2008, Cat. J/ApJS/176/59), we use the
parameter R, which scales with the excess of 0.25-1keV X-ray excess
emission in the region surrounding the star. By definition, an R=0
value is a region free of any X-ray emission while R≥2 is a target
situated in a bright X-ray emission region, and R=1 is the
intermediate case, generally a star near a diffuse enhancement or at
the edge of a bright X-ray emission region. See section 2.1.
Note (6): Sco OB2_2: Upper Scorpius; Sco OB2_3: Upper Centaurus Lupus; Sco
OB2_4: Lower Centaurus Crux following de Zeeuw et al. (1999, Cat.
J/AJ/117/354).
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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- 2 I2 --- Seq Star identification number
4- 13 A10 --- Name Star identification
15- 18 I4 km/s LoVel Lower velocity interval profile integrated
20- 23 I4 km/s UpVel Upper velocity interval profile integrated
25- 43 A19 --- Ion Ion identification and wavelength
45- 50 F6.1 km/s va ? Average velocity
52- 55 F4.1 km/s e_va ? Uncertainty in va
57 A1 --- l_logN Limit flag on logN (1)
58- 62 F5.2 [cm-2] logN Log apparent column density
63 A1 --- u_logN [:] Uncertainty flag on logN (2)
65- 68 F4.2 [cm-2] E_logN ? Upper level uncertainty in logN
70- 73 F4.2 [cm-2] e_logN ? Lower level uncertainty in logN
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Note (1): The symbol ">" indicates that the flux reaches zero and hence the
logN value is a lower limit. The symbol "<" indicates that there
is no detection; the value quoted is a 3σ upper limit.
Note (2): Uncertain owing to uncertainties in the continuum placement.
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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- 2 I2 --- Seq Star identification number
4- 13 A10 --- Name Star identification
15 A1 --- l_logNAlIII Limit flag on logNAlIII (7)
16- 20 F5.2 [cm-2] logNAlIII ? Log apparent AlIII column density
22- 25 F4.2 [cm-2] E_logNAlIII ? Upper limit uncertainty in logNAlIII
27- 30 F4.2 [cm-2] e_logNAlIII ? Lower limit uncertainty in logNAlIII
32 A1 --- l_logNSiIV Limit flag on logNSiIV (7)
33- 37 F5.2 [cm-2] logNSiIV Log apparent SiIV column density
39- 42 F4.2 [cm-2] E_logNSiIV ? Upper limit uncertainty in logNSiIV
44- 47 F4.2 [cm-2] e_logNSiIV ? Lower limit uncertainty in logNSiIV
49 A1 --- l_logNCIV Limit flag on logNCIV (7)
50- 54 F5.2 [cm-2] logNCIV Log apparent CIV column density
56- 59 F4.2 [cm-2] E_logNCIV ? Upper limit uncertainty in logNCIV
61- 64 F4.2 [cm-2] e_logNCIV ? Lower limit uncertainty in logNCIV
66 A1 --- l_logNNV Limit flag on logNNV (7)
67- 71 F5.2 [cm-2] logNNV ? Log apparent NV column density
72 A1 --- u_logNNV [:] Uncertainty flag in logNV (8)
74- 77 F4.2 [cm-2] E_logNNV ? Upper limit uncertainty in logNNV
79- 82 F4.2 [cm-2] e_logNNV ? Lower limit uncertainty in logNNV
84 A1 --- l_logNOVI Limit flag on logNOVI (7)
85- 89 F5.2 [cm-2] logNOVI ? Log apparent OVI column density
91- 94 F4.2 [cm-2] E_logNOVI ? Upper limit uncertainty in logNOVI
96- 99 F4.2 [cm-2] e_logNOVI ? Lower limit uncertainty in logNOVI
101 A1 --- l_lognAlIII Limit flag on lognAlIII (7)
102-106 F5.2 [cm-3] lognAlIII ? Log average AlIII density
108 A1 --- l_lognSiIV Limit flag on lognSiIV (7)
109-113 F5.2 [cm-3] lognSiIV Log average SiIV density
115 A1 --- l_lognCIV Limit flag on lognCIV (7)
116-120 F5.2 [cm-3] lognCIV Log average CIV density
122 A1 --- l_lognNV Limit flag on lognNV (7)
123-127 F5.2 [cm-3] lognNV ? Log average NV density
129 A1 --- l_lognOVI Limit flag on lognOVI (7)
130-134 F5.2 [cm-3] lognOVI ? Log average OVI density
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Note (7): The symbol ">" indicates that the flux reaches zero and hence the
apparent column density value is a lower limit. The symbol "<" 1|
indicates that there is no detection; the value quoted is a 3σ
upper limit.
Note (8): Uncertain owing to uncertainties in the continuum placement.
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Seq Star identification number
4- 13 A10 --- Name Star identification
15- 19 F5.2 --- Al/Si.d ? AlIII/SiIV from column density (9)
21- 24 F4.2 --- E_Al/Si.d ? Upper limit uncertainty in Al/Si.d
26- 29 F4.2 --- e_Al/Si.d ? Lower limit uncertainty in Al/Si.d
31 A1 --- f_C/Si.d Limit flag on C/Si.d (10)
32- 36 F5.2 --- C/Si.d ? CIV/SiIV from column density (9)
38- 41 F4.2 --- E_C/Si.d ? Upper limit uncertainty in C/Si.d
43- 46 F4.2 --- e_C/Si.d ? Lower limit uncertainty in C/Si.d
48 A1 --- l_C/N.d Limit flag on C/N.d (10)
49- 53 F5.2 --- C/N.d ? CIV/NV from column density (9)
54 A1 --- u_C/N.d [:] Uncertainty flag on C/N.d (11)
56- 59 F4.2 --- E_C/N.d ? Upper limit uncertainty in C/N.d
61- 64 F4.2 --- e_C/N.d ? Lower limit uncertainty in C/N.d
66 A1 --- l_N/O.d Limit flag on N/O.d (10)
67- 71 F5.2 --- N/O.d ? NV/OVI from column density (9)
72 A1 --- u_N/O.d [:] Uncertainty flag on N/O.d (11)
74- 77 F4.2 --- E_N/O.d ? Upper limit uncertainty in N/O.d
79- 82 F4.2 --- e_N/O.d ? Lower limit uncertainty in N/O.d
84 A1 --- l_C/O.d Limit flag on C/O.d (10)
85- 89 F5.2 --- C/O.d ? CIV/OVI from column density (9)
91- 94 F4.2 --- E_C/O.d ? Upper limit uncertainty in C/O.d
96- 99 F4.2 --- e_C/O.d ? Lower limit uncertainty in C/O.d
101-105 F5.2 --- Al/Si.p ? AlIII/SiIV from column density profile (12)
107-110 F4.2 --- E_Al/Si.p ? Upper limit uncertainty in Al/Si.p
112-115 F4.2 --- e_Al/Si.p ? Lower limit uncertainty in Al/Si.p
117-121 F5.2 --- C/Si.p ? CIV/SiIV from column density profile (12)
123-126 F4.2 --- E_C/Si.p ? Upper limit uncertainty in C/Si.p
128-131 F4.2 --- e_C/Si.p ? Lower limit uncertainty in C/Si.p
133-137 F5.2 --- C/N.p ? CIV/NV from column density profile (12)
138 A1 --- u_C/N.p [:] Uncertainty flag on C/N.p (11)
140-143 F4.2 --- E_C/N.p ? Upper limit uncertainty in C/N.p
145-148 F4.2 --- e_C/N.p ? Lower limit uncertainty in C/N.p
150-154 F5.2 --- N/O.p ? NV/OVI from column density profile (12)
156-159 F4.2 --- E_N/O.p ? Upper limit uncertainty in N/O.p
161-164 F4.2 --- e_N/O.p ? Lower limit uncertainty in N/O.p
166-170 F5.2 --- C/O.p ? CIV/OVI from column density profile (12)
172-175 F4.2 --- E_C/O.p ? Upper limit uncertainty in C/O.p
177-180 F4.2 --- e_C/O.p ? Lower limit uncertainty in C/O.p
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Note (9): Estimated from the total column density summarized in Table 4.
Note (10): Values preceded by "<" in the CIV/SiIV column are upper limit
(SiIV absorption is saturated), while in the NV/OVI column those are
3σ upper limits (NV is not detected). Values preceded by ">" in
the CIV/NV column are 3σ lower limit (NV is not detected).
Note (11): Uncertain owing to uncertainties in the continuum placement.
Note (12): Average results based on the pixel-by-pixel analysis of the AOD
ratio profiles.
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Seq Star identification number
4- 13 A10 --- Name Star identification
15 A1 --- R R parameters from Bowen et al. 2008, Cat.
J/ApJS/176/59 (existence of X-ray flux)
17- 22 A6 --- Ion Ion identification (1)
24- 25 I2 --- Num Component number
27- 32 F6.1 km/s Vlsr Local Standard of Rest velocity
34- 37 F4.1 km/s e_Vlsr Uncertainty in Vlsr
39- 42 F4.1 km/s b Doppler parameter
43 A1 --- u_b [:] Uncertainty flag on b (2)
45- 48 F4.1 km/s e_b ? Uncertainty in b
50- 54 F5.2 [cm-2] logN Log apparent column density
55 A1 --- u_logN [:] Uncertainty flag on logN (2)
57- 60 F4.2 [cm-2] e_logN ? Uncertainty in logN
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Note (1): Each doublet of a given ion was simultaneously fitted, but each
species was independently fitted.
Note (2): Indicates that the flux in this component is zero in both lines of
the doublet, except for N V where it indicates that the values are
uncertain owing to uncertainties in the continuum placement.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 23-Aug-2012