J/AJ/164/106 Parameters for 130 sight lines within 100pc (Linsky+, 2022)
Inhomogeneity within Local Interstellar Clouds.
Linsky J.L., Redfield S., Ryder D., Chasan-Taber A.
<Astron. J., 164, 106 (2022)>
=2022AJ....164..106L 2022AJ....164..106L
ADC_Keywords: Interstellar medium; Magnetic fields; Ultraviolet
Keywords: Interstellar clouds ; Interstellar dynamics ; Interstellar
magnetic fields ; Ultraviolet sources
Abstract:
Analysis of interstellar absorption lines observed in high-resolution
Hubble Space Telescope spectra of nearby stars provides temperatures,
turbulent velocities, and kinetic properties of warm interstellar
clouds. A new analysis of 97 interstellar-velocity components reveals
a wide range of temperatures and turbulent velocities within the Local
Interstellar Cloud (LIC) and the nearby Cluster of Interstellar Clouds
(CLIC). These variations appear to be random with Gaussian
distributions. We find no trends of these properties with stellar
distance or angles from the Galactic Center, magnetic field, the main
source of extreme-UV radiation (the star εCMa), the center of
the LIC, or the direction of inflowing interstellar matter into the
heliosphere. The spatial scale for temperature variations in the LIC
is likely smaller than 5100au, a distance that the Sun will traverse
in 1000yr. Essentially all velocity components align with known warm
clouds. We find that within 4pc of the Sun, space is completely filled
with partially ionized clouds, but at larger distances space is only
partially filled with partially ionized clouds. We find that the
neutral hydrogen number density in the LIC and likely other warm
clouds in the CLIC is about 0.10/cm3 rather than the 0.20/cm3
density that may be representative of only the immediate environment
of the LIC. The ~<3000-12000K temperature range for the gas is wider
than the predictions of thermal equilibrium theoretical models of the
warm neutral medium and warm ionized medium, and the high degree of
inhomogeneity within clouds argues against simple theoretical models.
Description:
All of the data presented in this paper were obtained from the
Mikulski Archive for Space Telescopes (MAST) at the Space Telescope
Science Institute.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 85 130 Parameters for all available sight lines within
100pc
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See also:
J/A+A/629/A139 : Closest stars to the Sun within 50pc catalog (Torres+, 2019)
http://doi.org/10.17909/gabn-m136 : MAST information about DOI 10.17909
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- ID Catalog numbers (1)
10- 22 A13 --- Name Star name
24- 33 A10 --- Cloud Interstellar cloud (2)
35- 39 F5.2 pc Dist [1.3/94.2] Distance to star
41- 45 F5.1 deg GLON [5.1/358.3] Galactic longitude
47- 51 F5.1 deg GLAT [-80.7/89.6] Galactic latitude
53- 53 A1 --- l_Tc [<] Limit flag on Tb
55- 61 F7.1 K Tc [0/27500]? Cloud temperature
63- 68 F6.1 K e_Tc [230/9100]? Error for Tc
70- 73 F4.2 km/s Vt [0/5.76]? Turbulent velocity for cloud
75- 79 F5.3 km/s e_Vt [0.05/4]? Error in Tv
81- 85 F5.2 [-] logHI [16.1/18.8] log, neutral hydrogen column density
through cloud
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Note (1): HD catalog numbers for the star at the end of the sight line when
available. When the star is too faint to be included in the HD catalog,
the GJ star number is listed instead. The column is blank for the few
stars without HD or GJ catalog numbers.
Note (2): If no known cloud has been identified for the absorber, the term
"unassigned" is used.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 18-Nov-2022