J/A+A/645/A14 GIBS sources equivalent widths (Zhao+, 2021)
The diffuse interstellar band around 8620 Å:
I. Methods and application to the GIBS data set.
Zhao H., Schultheis M., Recio-Blanco A., Kordopatis G., de Laverny P.,
Rojas-Arriagada A., Zoccali M., Surot F., Valenti E.
<Astron. Astrophys. 645, A14 (2021)>
=2021A&A...645A..14Z 2021A&A...645A..14Z (SIMBAD/NED BibCode)
ADC_Keywords: Interstellar medium ; Equivalent widths
Keywords: ISM: lines and bands - dust, extinction - Galaxy: bulge
Abstract:
We developed a set of procedures to automatically detect and measure
the DIB around 8620Å (the Gaia DIB) for a wide range of
temperatures. The method was tested on about 5000 spectra from the
Giraffe Inner Bulge Survey (GIBS; Zoccali et al.,
2014A&A...562A..66Z 2014A&A...562A..66Z), and 4194 reasonable fitting results were got. We
made use of the reddenings, E(J-Ks), from the extinction map developed
by Surot et al. (2020arXiv201002723S 2020arXiv201002723S). A linear correlation between
the equivalent width (EW) and E(J-Ks) was derived as E(J-Ks)/EW =
1.875, according to E(B-V)/EW = 2.721, which is highly consistent with
previous results toward similar sightlines. After a correction based
on the Vista Variables in the Via Lactea (VVV; Minniti et al.,
2010NewA...15..433M 2010NewA...15..433M) database for both EW and E(J-Ks), the coefficient
derived from individual GIBS fields, E(J-Ks)/EW=1.884, is also in
perfect agreement with literature values. Based on a subsample of 1015
stars toward the Galactic center, we determined a rest-frame
wavelength of the Gaia DIB as 8620.55Å. A Gaussian profile is
proved to be a proper and stable assumption for the Gaia DIB as no
intrinsic asymmetry is found.
Description:
Giraffe Inner Bulge Survey (GIBS; Zoccali et al., 2014A&A...562A..66Z 2014A&A...562A..66Z)
is a survey of red clump (RC) stars selected from the Vista Variables
in the Via Lactea (VVV; Minniti et al., 2010NewA...15..433M 2010NewA...15..433M) catalogs
in the Milky Way bulge. We make use of 4797 low-resolution spectra
from 20 observational fields in GIBS survey. The GIBS spectra analyzed
here are from the GIRAFFE LR8 setup at the resolution R=6500. The DIB
features on the spectra were fitted by a Gaussian profile using the
technique based on the Gaussian process after subtracting the stellar
components by a template of RC star. The equivalent width (EW) was
then calculated by the fitted depth and width of the profile. The
error of EW was estimated considering the contributions of both the
random noise and the mismatches between the GIBS spectra and the
template.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
catalog.dat 46 4194 Catalog
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See also:
II/348 : VISTA Variable in the Via Lactea Survey DR2 (Minniti+, 2017)
J/A+A/562/A66 : GIRAFFE Inner Bulge Survey (GIBS). I. (Zoccali+, 2014)
Byte-by-byte Description of file: catalog.dat
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Bytes Format Units Label Explanations
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1- 22 A22 --- GIBS GIBS target name
24- 28 F5.2 deg GLON [] Galactic longitude
30- 34 F5.2 deg GLAT Galactic latitude
36- 40 F5.3 0.1nm EW Measured equivalent width
42- 46 F5.3 0.1nm e_EW Error of equivalent width
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Acknowledgements:
He Zhao, he.zhao(at)oca.eu
(End) Patricia Vannier [CDS] 19-Nov-2020