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591. Diffuse Interstellar Bands in 49 stars
ID:
ivo://CDS.VizieR/J/MNRAS/358/563
Title:
Diffuse Interstellar Bands in 49 stars
Short Name:
J/MNRAS/358/563
Date:
21 Oct 2021
Publisher:
CDS
Description:
We relate the equivalent widths of 11 diffuse interstellar bands, measured in the spectra of 49 stars, to different colour excesses in the ultraviolet. We find that most of the observed bands correlate positively with the extinction in the neighbourhood of the 2175{AA} bump. Correlation with colour excesses in other parts of the extinction curve is more variable from one diffuse interstellar band to another; we find that some diffuse bands (5797, 5850 and 6376{AA}) correlate positively with the overall slope of the extinction curve, while others (5780 and 6284{AA}) exhibit negative correlation. We discuss the implications of these results on the links between the diffuse interstellar band carriers and the properties of the interstellar grains.
592. Diffuse Interstellar Bands in 150 stars
ID:
ivo://CDS.VizieR/J/A+A/544/A136
Title:
Diffuse Interstellar Bands in 150 stars
Short Name:
J/A+A/544/A136
Date:
21 Oct 2021
Publisher:
CDS
Description:
Diffuse interstellar bands (DIBs) measured in stellar spectra contain information on the amount of interstellar (IS) matter that is distributed along the line-of-sight, and similarly to other absorbing species may be used to locate IS clouds. Here we present a new database of 5780.5 and 6283.8{AA} DIB measurements. Those two DIBs have the advantage that they are strong and also broad enough to be detectable in cool-star spectra. We also study their correlation with the reddening.
593. Diffuse interstellar bands. IV.
ID:
ivo://CDS.VizieR/J/ApJ/708/1628
Title:
Diffuse interstellar bands. IV.
Short Name:
J/ApJ/708/1628
Date:
21 Oct 2021
Publisher:
CDS
Description:
In a sample of 114 diffuse cloud sightlines spanning a wide range of interstellar environments, we find the equivalent widths of the diffuse interstellar bands (DIBs) {lambda}6196.0 and {lambda}6613.6 to be extremely well correlated, with a correlation coefficient of 0.986. A maximum likelihood functional relationship analysis shows that the observations are consistent with a perfect correlation if the observational errors, which are dominated by continuum placement and other systematics such as interfering lines, have been underestimated by a factor of 2. The quality of this correlation far exceeds other previously studied correlations, such as that between the {lambda}5780.5 DIB and either the color excess or the atomic hydrogen column density. The unusually tight correlation between these two DIBs would seem to suggest that they might represent the first pair of DIBs known to be due to the same molecular carrier. However, further theoretical work will be required to determine whether the different linewidths and band shapes of these two DIBs can be consistent with a common carrier. If the two DIBs do not in fact share the same molecular carrier, their two carriers must be chemically very closely related.
594. Diffuse ionized gas database DIGEDA
ID:
ivo://CDS.VizieR/J/other/RMxAA/45.261
Title:
Diffuse ionized gas database DIGEDA
Short Name:
J/other/RMxAA/45
Date:
21 Oct 2021
Publisher:
CDS
Description:
Studies of the Diffuse Ionized Gas (DIG) have progressed without providing so far any strict criterion to distinguish DIGs from HII regions. In this work, we compile the emission line measurements of 29 galaxies that are available in the scientific literature, thereby setting up the first DIG database DIGEDA. Making use of this database, we proceeded to analyze global properties of the DIG using the [NII]6583/Halpha, [OI]6300/Halpha, [OIII]5007/Hbeta and [SII]6716/Halpha lines ratios, including the Halpha emission measure. This analysis leads us to conclude that the [NII]/Halpha ratio provides an objective criterion for distinguishing whether an emission region is DIG or an HII region, while the EM(Halpha) is a useful quantity only when the galaxies are considered individually. Finally, we find that the emission regions of Irr galaxies classified as DIG in the literature appear in fact to be much more similar to HII regions than to the DIGs of spiral galaxies.
595. Diffuse ionized gas in the Antennae galaxy
ID:
ivo://CDS.VizieR/J/A+A/611/A95
Title:
Diffuse ionized gas in the Antennae galaxy
Short Name:
J/A+A/611/A95
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Antennae galaxy (NGC 4038/39) is the closest major interacting galaxy system and is therefore often studied as a merger prototype. We present the first comprehensive integral field spectroscopic dataset of this system, observed with the MUSE instrument at the ESO VLT. We cover the two regions in this system which exhibit recent star formation: the central galaxy interaction and a region near the tip of the southern tidal tail. In these fields, we detect HII regions and diffuse ionized gas to unprecedented depth. About 15% of the ionized gas was undetected by previous observing campaigns. This newly detected faint ionized gas is visible everywhere around the central merger, and shows filamentary structure. We estimate diffuse gas fractions of about 60% in the central field and 10% in the southern region. We are able to show that the southern region contains a significantly different population of HII regions, showing fainter luminosities. By comparing HII region luminosities with the HST catalog of young star clusters in the central field, we estimate that there is enough Lyman-continuum leakage in the merger to explain the amount of diffuse ionized gas that we detect. We compare the Lyman-continuum escape fraction of each HII region against emission line ratios that are sensitive to the ionization parameter. While we find no systematic trend between these properties, the most extreme line ratios seem to be strong indicators of density bounded ionization. Extrapolating the Lyman-continuum escape fractions to the southern region, we conclude that simply from the comparison of the young stellar populations to the ionized gas there is no need to invoke other ionization mechanisms than Lyman-continuum leaking HII regions for the diffuse ionized gas in the Antennae.
596. Diffuse OVII and OVIII emission from XMM
ID:
ivo://CDS.VizieR/J/ApJS/202/14
Title:
Diffuse OVII and OVIII emission from XMM
Short Name:
J/ApJS/202/14
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an all-sky catalog of diffuse OVII and OVIII line intensities, extracted from archival XMM-Newton observations. This catalog supersedes our previous catalog (Henley et al., 2010, Cat. J/ApJS/187/388), which covered the sky between l=120{deg} and l=240{deg}. We attempted to reduce the contamination from near-Earth solar wind charge exchange (SWCX) emission by excluding times of high solar wind proton flux from the data. Without this filtering, we were able to extract measurements from 1868 observations. With this filtering, nearly half of the observations became unusable, and only 1003 observations yielded measurements. The OVII and OVIII intensities are typically ~2-11 and <~3 photons/cm^2^/s/sr (line unit, L.U.), respectively, although much brighter intensities were also recorded. Our data set includes 217 directions that have been observed multiple times by XMM-Newton. The time variation of the intensities from such directions may be used to constrain SWCX models.
597. Digitized First Byurakan Survey
ID:
ivo://vopdc.obspm/dfbs
Title:
Digitized First Byurakan Survey
Short Name:
DFBS
Date:
10 Jan 2017
Publisher:
Paris Astronomical Data Centre
Description:
The First Byurakan Survey (FBS) is the largest and the first systematic objective prism survey of the extragalactic sky. It covers 17,000 sq.deg. in the Northern sky together with a high galactic latitudes region in the Southern sky. The FBS has been carried out by B.E. Markarian, V.A. Lipovetski and J.A. Stepanian in 1965-1980 with the Byurakan Observatory 102/132/213 cm (40"/52"/84") Schmidt telescope using 1.5 deg. prism. Each FBS plate contains low-dispersion spectra of some 15,000-20,000 objects; the whole survey consists of about 20,000,000 objects.
598. Digitized First Byurakan Survey (DFBS) Extracted Spectra
ID:
ivo://byu.arvo/dfbsspec/q/spectra
Title:
Digitized First Byurakan Survey (DFBS) Extracted Spectra
Date:
24 Aug 2020 16:45:07
Publisher:
The staff at the ArVO Data Center
Description:
This table contains basic metadata as well as the spectra from the Digital First Byurakan Survey (DFBS).
599. Digitized First Byurakan Survey (DFBS) Extracted Spectra
ID:
ivo://byu.arvo/dfbsspec/q/raw_spectra
Title:
Digitized First Byurakan Survey (DFBS) Extracted Spectra
Date:
06 Dec 2018 16:23:36
Publisher:
Byurakan Astrophysical Observatory
Description:
Raw metadata for the spectra, to be combined with image metadata like date_obs and friends for a complete spectrum descriptions. This also contains spectral and flux points in array-valued columns.
600. Digitized First Byurakan Survey (DFBS) Extracted Spectra
ID:
ivo://org.gavo.dc/dfbsspec/q/spectra
Title:
Digitized First Byurakan Survey (DFBS) Extracted Spectra
Short Name:
dfbsspec.spectra
Date:
27 Dec 2024 08:31:13
Publisher:
The GAVO DC team
Description:
This table contains basic metadata as well as the spectra from the Digital First Byurakan Survey (DFBS).

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