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Related papers: Identification of H$_2$CCC as a diffuse interstell…

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We present interstellar C II (1334.5323 \AA) and C II* (1335.7077 \AA) column density measurements along 14 Galactic sight-lines. These sight-lines sample a variety of Galactic disk environments and include paths that range nearly two…

Astrophysics of Galaxies · Physics 2011-02-18 Veena S. Parvathi , Ulysses J. Sofia , Jayant Murthy , B. R. S. Babu

Dwarf carbon (dC) stars, main sequence stars showing carbon molecular bands, were initially thought to be an oxymoron since only AGB stars dredge carbon into their atmospheres. Mass transfer from a former AGB companion that has since faded…

The disk around the Herbig Ae star HD\,169142 was imaged and resolved at 18.8 and 24.5\,$\mu$m using Subaru/COMICS. We interpret the observations using a 2D radiative transfer model and find evidence for the presence of a large gap. The MIR…

We present a new high signal-to-noise (S/N) observations of the Diffuse Interstellar Bands (DIBs) in the Local Bubble and its surroundings. We observed 432 sightlines and obtain the equivalent widths of $\lambda$5780 and $\lambda$5797 \AA\…

Astrophysics of Galaxies · Physics 2015-06-23 Amin Farhang , Habib G. Khosroshahi , Atefeh Javadi , Jacco Th. van Loon

We searched for shocked carbon chain chemistry (SCCC) sources with C$_3$S abundances surpassing those of HC$_5$N towards the dark cloud L1251, using the Effelsberg telescope at K-band (18 -- 26\,GHz). L1251-1 and L1251-3 are identified as…

Published interpretations of the relative intensity variations of the Unidentified Infrared Bands (UIBs) and their underlying continuum are discussed. An alternative model is proposed, in which a single carrier for both emits a) mostly a…

Astrophysics · Physics 2009-11-10 Renaud Papoular

Context: There have been many attempts to identify families of diffuse interstellar bands (DIBs) with perfectly correlating band strengths. Although major efforts have been made to classify broadly based DIB families and important insights…

The Sun lies in the middle of an enormous cavity of a million degree gas, known as the Local Bubble. The Local Bubble is surrounded by a wall of denser neutral and ionized gas. The Local Bubble extends around 100 pc in the plane of Galaxy…

Astrophysics of Galaxies · Physics 2015-11-24 Jacco Th. van Loon , Amin Farhang , Atefeh Javadi , Mandy Bailey , Habib Khosroshahi

We report about a suprisingly good correlation between the equivalent width of the diffuse interstellar band (DIB) at 8620 Ang and the interstellar reddening. Such a correlation offers bright prospects in using the 8620 Ang DIB as a tracer…

Astrophysics · Physics 2007-05-23 Ulisse Munari

The sources behind numerous key diffuse interstellar bands (DIBs) remain elusive, and thus evidence is presented here that a family of seven anionic hydrogen atomic clusters (H(-)2n+1, n = 1 to 7) are pertinent contributors. Configuration…

Astrophysics of Galaxies · Physics 2019-12-30 Lulu Huang , Cherif F. Matta , Daniel Majaess , Tina Harriott , Joseph Capitani , Lou Massa

Discovered almost a century ago, the Diffuse Interstellar Bands (DIBs) still lack convincing and comprehensive identification. Hundreds of DIBs have now been observed in the near-ultraviolet (NUV), visible and near-infrared (NIR). They are…

Astrophysics of Galaxies · Physics 2019-03-20 M. G. Rawlings , A. J. Adamson , C. C. M. Marshall , P. J. Sarre

In this work we present the results of a systematic search for diffuse bands (DBs, hereafter) in the circumstellar envelopes of a carefully selected sample of post-AGB stars. We concentrated on the analysis of 9 of the DBs most commonly…

Astrophysics · Physics 2009-11-13 R. Luna , N. L. J. Cox , M. A. Satorre , D. A. Garcia-Hernandez , O. Suarez , P. Garcia-Lario

We present the largest sample to-date of intermediate-resolution blue-to-red optical spectra of B-type supergiants in M31 and undertake the first survey of diffuse interstellar bands (DIBs) in this galaxy. Spectral classifications, radial…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Martin A. Cordiner , Nick L. J. Cox , Christopher J. Evans , Carrie Trundle , Keith T. Smith , Peter J. Sarre , Karl D. Gordon

We present the first results of a systematic search for Diffuse Interstellar Bands in a carefully selected sample of post-AGB stars observed with high resolution optical spectroscopy. These stars are shown to be ideal targets to study this…

Astrophysics · Physics 2009-11-13 P. Garcia-Lario , R. Luna , M. A. Satorre

We present ultra-high resolution (0.32 km/s) spectra obtained with the 3.9m Anglo-Australian Telescope (AAT) and Ultra-High-Resolution Facility (UHRF), of interstellar NaI D1, D2, Ca II K, K I and CH absorption toward two high galactic…

Astrophysics · Physics 2009-10-30 M. S. Sahu , J. C. Blades , L. He , D. Hartmann , M. J. Barlow , I. A. Crawford

We present deep, narrowband imaging of the nearby spiral galaxy M101 and its satellites to analyze the oxygen abundances of their HII regions. Using CWRU's Burrell Schmidt telescope, we add to the narrowband dataset of the M101 Group,…

Astrophysics of Galaxies · Physics 2023-07-17 Ray Garner , J. Christopher Mihos , Paul Harding , Aaron E. Watkins , Stacy S. McGaugh

High resolution (0.15") Very Large Array observations of 7 mm continuum and H53a line emission toward the hypercompact H II region G28.20-0.04N reveal the presence of large-scale ordered motions. We find a velocity gradient of 1000 km/s/pc…

Astrophysics · Physics 2009-06-23 M. Sewilo , E. Churchwell , S. Kurtz , W. M. Goss , P. Hofner

We use the single-dish radio telescope FAST to map the HI in the tidally interacting NGC 4631 group with a resolution of 3.24$'$ (7 kpc), reaching a 5-$\sigma$ column density limit of $10^{17.9}$ cm$^{-2}$ assuming a line width of 20 km…

Interstellar lines observed toward stellar targets change slowly over long timescales, mainly due to the proper motion of the background target relative to the intervening clouds. On longer timescales, the cloud's slowly changing physical…

In this poster we show our preliminary analysis of DIBs (Diffuse Interstellar Bands) and other interstellar absorption lines with the purpose of understanding their origin and their relationship with extinction. We use the biggest Galactic…