J/A+A/676/A132 Extinction curves in the Milky Way (Siebenmorgen+, 2023)
Dark dust. III. The high-quality reddening curve sample.
Scrutinizing extinction curves in the Milky Way.
Siebenmorgen R., Smoker J., Krelowski J., Gordon K., Chini R.
<Astron. Astrophys. 676, A132 (2023)>
=2023A&A...676A.132S 2023A&A...676A.132S (SIMBAD/NED BibCode)
ADC_Keywords: Milky Way ; Stars, early-type ; Extinction ; Optical
Keywords: dust, extinction - ISM: clouds - stars: early-type
Abstract:
The nature of dust in the diffuse interstellar medium can be best
investigated by means of reddening curves where only a single
interstellar cloud lies between the observer and the background
source. Published reddening curves often suffer from various
systematic uncertainties. We merge a sample of 895 reddening curves of
stars for which both FORS2 polarisation spectra and UVES
high-resolution spectra are available. The resulting 111 sightlines
toward OB-type stars have 175 reddening curves. For these stars, we
derive their spectral type from the UVES high-resolution spectroscopy.
To obtain high-quality reddening curves we exclude stars with
composite spectra in the IUE/FUSE data due to multiple stellar
systems. Likewise, we omit stars that have uncertain spectral type
designations or stars with photometric variability. We neglect stars
that show inconsistent parallaxes when comparing DR2 and DR3 from
GAIA. Finally, we identify stars that show differences in the space
and ground-based derived reddening curves between 0.28um and the
U-band or in RV. In total, we find 53 stars with one or more
reddening curves passing the rejection criteria. This provides the
highest quality Milky Way reddening curve sample available today.
Averaging the curves from our high-quality sample, we find
RV=3.1±0.4, confirming previous estimates. A future paper in this
series will use the current sample of precise reddening curves and
combine them with polarisation data to study the properties of dark
dust.
Description:
The Milky Way reddening derived from the high-quality sample
for translucent clouds and for single-cloud sightlines of
the diffuse ISM.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
fig9d.dat 27 315 Milky Way reddening E=E(lambda-V)/E(B-V) of
the diffuse ISM
fig9t.dat 27 315 Milky Way reddening E=E(lambda-V)/E(B-V) of
translucent clouds
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See also:
J/A+A/641/A35 : Dark dust and single-cloud sightlines in ISM
(Siebenmorgen+, 2020)
Byte-by-byte Description of file: fig9d.dat fig9t.dat
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Bytes Format Units Label Explanations
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2- 9 F8.3 um lambda Wavelength
13- 18 F6.3 --- E Milky Way reddening (E(lambda-V)/E(B-V))
23- 27 F5.3 --- e_E Milky Way reddening error
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Acknowledgements:
Ralf Siebenmorgen, rsiebenm(at)eso.org
References:
Siebenmorgen et al., , Paper I 2020A&A...641A..35S 2020A&A...641A..35S, Cat. J/A+A/641/A35
Siebenmorgen, Paper II 2023A&A...670A.115S 2023A&A...670A.115S
(End) Patricia Vannier [CDS] 05-Jul-2023