VLT/X-Shooter survey of near-infrared diffuse interstellar bands

AbstractIn addition to the hundreds of known visual-wavelength Diffuse Interstellar Bands (DIBs), a number of DIBs in the near-infrared (NIR) are now also known to exist. We present here high-resolution UKIRT echelle spectroscopy of two of the NIR DIBs toward sightlines exhibiting a range of visual extinctions. Variations in the strengths and profile shapes of the bands are considered in the context of known properties of the narrow DIBs at visual wavelengths.

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The new infrared diffuse interstellar bands in the Galactic center

Proceedings of the International Astronomical Union ◽

10.1017/s1743921314000192 ◽

2013 ◽

Vol 9 (S303) ◽

pp. 75-77

Author(s):

T. R. Geballe ◽

F. Najarro ◽

D. de la Fuente ◽

D. F. Figer ◽

A. J. Adamson ◽

...

Keyword(s):

Near Infrared ◽

Galactic Center ◽

Overwhelming Majority ◽

Specific Identification ◽

General Consensus ◽

Diffuse Interstellar Bands ◽

Infrared Wavelengths ◽

Band Spectra ◽

The Universe ◽

Absorption Features

The diffuse interstellar bands (DIBs) are a set of absorption features, some of which are broad (“diffuse”), that are formed in the diffuse ISM. Since their discovery nearly a century ago their numbers have increased to over 500. The strongest of these are known to be ubiquitous in the universe. There is general consensus that they are produced by large carbon-bearing molecules; however, no specific identification of any single DIB has survived scrutiny. The overwhelming majority of DIBs are at optical and very near infrared wavelengths. In 1990 two DIBs were identified in J-band spectra, at 1.18 μm and 1.31 μm by Joblin et al. (1990); until recently these were the longest wavelength examples known.

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Near-infrared diffuse interstellar bands in APOGEE telluric standard star spectra

Astronomy and Astrophysics ◽

10.1051/0004-6361/201630088 ◽

2017 ◽

Vol 600 ◽

pp. A129 ◽

Cited By ~ 11

Author(s):

M. Elyajouri ◽

R. Lallement ◽

A. Monreal-Ibero ◽

L. Capitanio ◽

N. L. J. Cox

Keyword(s):

Near Infrared ◽

Standard Star ◽

Diffuse Interstellar Bands

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Fullerenes as carriers of extinction, diffuse interstellar bands and anomalous microwave emission

Proceedings of the International Astronomical Union ◽

10.1017/s1743921308021170 ◽

2008 ◽

Vol 4 (S251) ◽

pp. 57-62 ◽

Cited By ~ 5

Author(s):

Susana Iglesias-Groth

Keyword(s):

Cross Sections ◽

Near Infrared ◽

Microwave Emission ◽

Microwave Background ◽

Potential Explanation ◽

Rotation Rates ◽

Diffuse Interstellar Bands ◽

Dipole Emission ◽

Peak Energy ◽

Semiempirical Models

AbstractAccording to semiempirical models, photoabsorption by fullerenes (single and multishell) could explain the shape, width and peak energy of the most prominent feature of the interstellar absorption, the UV bump at 2175 Å. Other weaker transitions are predicted in the optical and near-infrared providing a potential explanation for diffuse interstellar bands. In particular, we find that several fullerenes could contribute to the well known strong DIB at 4430 Å. Comparing cross sections and available data for this DIB and the UV bump we estimate a density of fullerenes in the diffuse interstellar medium of 0.1–0.2 ppm. These molecules could then be a major reservoir for interstellar carbon. We also study the rotation rates and electric dipole emission of hydrogenated icosahedral fullerenes. We investigate these molecules as potential carriers of the anomalous (dust-correlated) microwave emission recently detected by several cosmic microwave background experiments.

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Preface: Special Session SpS16 Unexplained Spectral Phenomena in the Interstellar Medium

Proceedings of the International Astronomical Union ◽

10.1017/s1743921315001672 ◽

2012 ◽

Vol 10 (H16) ◽

pp. 695-696

Keyword(s):

Interstellar Medium ◽

Near Infrared ◽

Milky Way ◽

Magellanic Clouds ◽

Special Session ◽

Milky Way Galaxy ◽

Sn 1987A ◽

Diffuse Interstellar Bands ◽

External Galaxies

There are several outstanding mysteries in interstellar medium spectroscopy which have remained unsolved after decades of effort. The diffuse interstellar bands (DIBs) have been known for almost a century (Heger 1922). Although more than 400 bands from the near UV to near infrared have been detected, none of them has been identified. In the Milky Way Galaxy, DIBs have been seen towards over one hundred stars. In the Magellanic Clouds, DIBs have been seen in the spectrum of SN 1987A as well as in the spectra of reddened stars (Ehrenfreund et al. 2002). DIB carriers in the interstellar medium of external galaxies can be probed by supernovae (Sollerman et al. 2005), and DIBs have been detected in external galaxies with redshifts up to 0.5 (Sarre 2006).

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Fullerenes, PAHs, Amino Acids and High Energy Astrophysics

Acta Polytechnica CTU Proceedings ◽

10.14311/app.2014.01.0038 ◽

2014 ◽

Vol 1 (1) ◽

pp. 38-41

Author(s):

Susana Iglesias-Groth

Keyword(s):

Amino Acids ◽

Near Infrared ◽

High Energy ◽

Laboratory Work ◽

Near Ir ◽

Diffuse Interstellar Bands ◽

The Galaxy ◽

Spectral Characterisation ◽

Fullerene Formation ◽

Ir Bands

We present theoretical, observational and laboratory work on the spectral properties of fullerenes and hydrogenated fullerenes. Fullerenes in its various forms (individual, endohedral, hydrogenated, etc.) can contribute to the UV bump in the extinction curves measured in many lines of sight of the Galaxy. They can also produce a large number of absorption features in the optical and near infrared which could be associated with diffuse interstellar bands. We summarise recent laboratory work on the spectral characterisation of fullerenes and hydrogenated fullerenes (for a range of temperatures). The recent detection of mid-IR bands of fullerenes in various astrophysical environments (planetary nebulae, reflection nebulae) provide additional evidence for a link between fullerene families and diffuse interstellar bands. We describe recent observational work on near IR bands of C<sub>60</sub><sup>+</sup> in a protoplanetary nebula which support fullerene formation during the post-AGB phase. We also report on the survival of fullerenes to irradiation by high energy particles and gamma photons and laboratory work to explore the chemical reactions that take place when fullerenes are exposed to this radiations in the presence of water, ammonia and other molecules as a potential path to form amino acids.

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The Promise of Recent and Future Observatories and Instruments

Proceedings of the International Astronomical Union ◽

10.1017/s1743921313016190 ◽

2013 ◽

Vol 9 (S297) ◽

pp. 389-398

Author(s):

L Kaper

Keyword(s):

Potential Role ◽

Near Infrared ◽

Local Group ◽

Infrared Wavelength ◽

Stellar Spectroscopy ◽

Diffuse Interstellar Bands ◽

The Galaxy ◽

Substantial Progress ◽

Large Telescopes ◽

Made In

AbstractThe identification of the carrier(s) of diffuse interstellar bands (DIBs) is one of the oldest mysteries in stellar spectroscopy. With the advent of 8-10m-class telescopes substantial progress has been made in measuring the properties of DIBs in the optical and near-infrared wavelength domain, not only in the Galaxy, but also in different environments encountered in Local Group galaxies and beyond. Still, the DIB carriers have remained unidentified. The coming decade will witness the development of extremely large telescopes (GMT, TMT and E-ELT) and their instrumentation. In this overview I will highlight the current instrumentation plan of these future observatories, emphasizing their potential role in solving the enigma of the DIBs.

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