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Nano-diamonds remain an intriguing component of the dust in the few sources where they have been observed in emission. This work focusses on the nano-diamonds observed in circumstellar discs and is an attempt to derive critical information…

Astrophysics of Galaxies · Physics 2022-09-07 Anthony P. Jones

Several interstellar environments produce 'anomalous microwave emission', with brightness-peaks at tens-of-gigahertz frequencies. The emission's origins are uncertain - rapidly-spinning nano-particles could emit electric-dipole radiation,…

Solar and Stellar Astrophysics · Physics 2018-06-13 Jane Greaves , Anna Scaife , David Frayer , Dave Green , Brian Mason , Alexis Smith

We have used different spectroscopic techniques to obtain a consistent quantitative absorption spectrum of a sample of meteoritic nano-diamonds in the wavelength range from the vacuum ultraviolet (0.12 $\mu$m) to the far infrared (100…

Astrophysics · Physics 2009-11-10 H. Mutschke , A. C. Andersen , C. Jaeger , Th. Henning , A. Braatz

The eventual presence of the diamond carbon allotrope in space is discussed in numerous theoretical and experimental studies. The review summarizes the principal mechanisms of nanodiamond formation and experimental results of spectroscopic…

Earth and Planetary Astrophysics · Physics 2024-07-30 A. A. Shiryaev

Laboratory analyses on fine-grained diamond residues from primitive meteorites have shown that nano-diamonds represent the most abundant form of presolar dust preserved in meteoritic samples. The presolar diamonds carry isotopic anomalies…

Astrophysics · Physics 2007-05-23 A. C. Andersen , U. G. Jorgensen , F. M. Nicolaisen , P. G. Sorensen , K. Glejbol

Nano-diamonds have been observed in only a handful of circumstellar regions $10-100$\,\tiny{ A.U.} from moderately bright stars ($T_{\rm eff} \sim 8,000-10,000$\,K). They have also been extracted from primitive meteorites; some of these are…

Astrophysics of Galaxies · Physics 2022-01-26 A. P. Jones

The study of scattering and extinction properties of possible nanodiamond grains in the ISM are reported. Calculations using Discrete Dipole Approximation (DDA) for varying ellipsoidal shapes and sizes from 2.5 to $10 nm$ are considered.…

Solar and Stellar Astrophysics · Physics 2015-05-14 Rakesh K Rai , Shantanu Rastogi

Nanodust, which undergoes stochastic heating by single starlight photons in the interstellar medium, ranges from angstrom-sized large molecules containing tens to thousands of atoms (e.g. polycyclic aromatic hydrocarbon molecules) to grains…

Astrophysics of Galaxies · Physics 2015-06-11 Aigen Li , Ingrid Mann

It has been proposed, or confirmed, that diamond nanoparticles exist in various environments in space: close to active galactic nuclei, in the vicinity of supernovae and pulsars, in the interior of several planets in the Solar system, in…

Solar and Stellar Astrophysics · Physics 2018-04-24 G. Bilalbegovic , A. Maksimovic , L. A. Valencic

We report on a concerted effort aimed at understanding the origin and history of the pre-solar nanodiamonds in meteorites including the astrophysical sources of the observed isotopic abundance signatures. This includes measurement of light…

Solar and Stellar Astrophysics · Physics 2012-11-27 Ulrich Ott , Astrid Besmehn , Khalil Farouqi , Oliver Hallmann , Peter Hoppe , Karl-Ludwig Kratz , Karl Melber , Anton Wallner

We explore the possibility that the steepening observed shortward of 1000A in the energy distribution of quasars may result from absorption by dust, being either intrinsic to the quasar environment or intergalactic. We find that a dust…

We have carried out a survey of 60 Herbig Ae/Be stars in the 3 micron wavelength region in search for the rare spectral features at 3.43 and 3.53 micron. These features have been attributed to the presence of large, hot, hydrogen-terminated…

Astrophysics · Physics 2009-11-11 B. Acke , M. E. van den Ancker

Based on extensive laboratory characterization of presolar nanodiamonds extracted from mete-orites, we have proposed a novel approach to detect nanodiamonds at astrophysical objects using the 7370 {\AA} emission band arising from lattice…

Solar and Stellar Astrophysics · Physics 2019-01-30 Andrey Shiryaev , Laurence Sabin , Gennady Valyavin , Gazinur Galazutdinov

Nano-crystalline diamond is a new carbon phase with numerous intriguing physical and chemical properties and applications. Small doped nanodiamonds for example do find increased use as novel quantum markers in biomedical applications.…

We calculate the dust emission expected at 3.43 and 3.53 microns if meteoritic (i.e. hydrogenated) nanodiamonds are responsible for most of the far-UV break observed in quasars. We integrate the UV flux that hydrogenated nanodiamonds must…

Astrophysics · Physics 2009-11-13 J. A. de Diego , L. Binette , P. Ogle , A. C. Andersen , S. Haro Corzo , M. Wold

The spectral energy distribution of quasars shows a sharp steepening of the continuum shortward of ~ 1100 A. The steepening could be a result of dust absorption. We present a dust extinction model which considers crystalline carbon grains…

Astrophysics · Physics 2009-11-11 L. Binette , A. C. Andersen , H. Mutschke , S. Haro-Corzo

Interstellar dust spans a wide range in size distribution, ranging from ultrasmall grains of a few Angstroms to micrometer-size grains. While the presence of nanometer-size dust grains in the Galactic interstellar medium was speculated six…

Astrophysics of Galaxies · Physics 2018-11-14 Yanxia Xie , Luis C. Ho , Aigen Li , Jinyi Shangguan

Photoluminescence spectra show that silicon impurity is present in lattice of some nanodiamond grains (ND) of various chondrites as a silicon-vacancy (SiV) defect. The relative intensity of the SiV band in the diamond-rich separates depends…

Solar and Stellar Astrophysics · Physics 2015-05-27 A. A. Shiryaev , A. V. Fisenko , L. F. Semjonova , A. A. Khomich , I. I. Vlasov

NV centers in diamond are generally recognized as highly promising as indefinitely stable highly efficient single-photon sources. We report an experimental quantification of the brightness, radiative decay rate, nonradiative decay rate and…

Optics · Physics 2015-06-12 Abbas Mohtashami , A. Femius Koenderink

Aims. A sample of early B-type stars in OB associations and the field within the solar neighbourhood is studied comprehensively. Present-day abundances for the astrophysically most interesting chemical elements are derived. Methods.…

Solar and Stellar Astrophysics · Physics 2012-03-29 Maria-Fernanda Nieva , Norbert Przybilla
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