Results 71 to 80 of about 156,409 (216)

The abundance of interstellar chlorine in the galaxy [PDF]

Monthly Notices of the Royal Astronomical Society, 1984
Des largeurs equivalentes nouvellement deduites de spectres IUE ont ete combinees a des largeurs equivalentes de Copernicus pour evaluer les abondances interstellaires du chlore pour plus de 40 lignes de visee galactiques. L'abondance presente une decroissance marquee avec l'augmentation de n(H) suivant la relation approchee a(Cl)≃4,9-0,3 log [n(H) cm −
A. W. Harris, G. E. Bromage
openaire   +1 more source

Optimizing End-to-End System Performance for Millimeter and Submillimeter Spectroscopy of Protostars: Wideband Heterodyne Receivers and Sideband-Deconvolution Techniques for Rapid Molecular-Line Surveys [PDF]

, 2011
This thesis describes the construction, integration, and use of a new 230-GHz ultra-wideband heterodyne receiver, as well as the development and testing of a new sideband-deconvolution algorithm, both designed to enable rapid, sensitive molecular-line ...
Sumner, Matthew Casey
core   +1 more source

Raman analysis of organic refractory materials after energetic processing: Evidence for amorphous carbon on TNOs and comets

Meteoritics &Planetary Science, Volume 61, Issue 8, Page 1994-2015, August 2026.
Abstract Amorphous carbon (αC) is found in various extraterrestrial particles, including those thought to originate from the outer Solar System. αC can form through two main processes involving C‐rich materials: exposure to energetic charged particles and thermal processing.
M. Germanà, A. Vyjidak, G. A. Baratta, B. M. Giuliano, R. G. Urso, C. Scirè, D. Fulvio, T. Grassi, P. Jusko, P. Caselli, M. E. Palumbo   +10 more
wiley   +1 more source

Detection of Deuterated Hydrocarbon Nanoparticles in the Whirlpool Galaxy, M51

The Astrophysical Journal Letters
Deuteration of hydrocarbon material, including polycyclic aromatic hydrocarbons (PAHs), has been proposed to account for the low gas-phase abundances of D in the interstellar medium (ISM). JWST spectra of four star-forming regions in M51 show an emission
B. T. Draine, Karin Sandstrom, Daniel A. Dale, J.-D. T. Smith, Ryan Chown, Grant P. Donnelly, Sara E. Duval, Cory M. Whitcomb, Angela Adamo, L. Armus, Danielle A. Berg, Torsten Böker, Alberto D. Bolatto, Martha L. Boyer, Daniela Calzetti, B. G. Elmegreen, Brandt A. L. Gaches, Karl D. Gordon, L. K. Hunt, R. C. Kennicutt, Ralf S. Klessen, Thomas S.-Y. Lai, Adam K. Leroy, Sean T. Linden, Alex Pedrini, Noah S. J. Rogers, Julia C. Roman-Duval, Eva Schinnerer, Evan B. Skillman, Fabian Walter, Tony D. Weinbeck, Benjamin F. Williams   +31 more
doaj   +1 more source

Interstellar Atomic Abundances

, 2003
A broad array of interstellar absorption features that appear in the ultraviolet spectra of bright sources allows us to measure the abundances and ionization states of many important heavy elements that exist as free atoms in the interstellar medium.
openaire   +2 more sources

Electrons in the cosmic radiation [PDF]

, 1990
The nature of cosmic ray electrons and their radiation in the Universe has been studied. A convection associated diffusion model is proposed to describe the main characteristics of the large-scale distribution of cosmic ray electrons in the Galaxy: (1) a
Chi, Xinyu, Chi, X
core  

The influence of galactic cosmic rays on ion-neutral hydrocarbon chemistry in the upper atmospheres of free-floating exoplanets [PDF]

, 2014
The authors highlight financial support of the European Community under the FP7 by an ERC starting grant.Cosmic rays may be linked to the formation of volatiles necessary for prebiotic chemistry.
P. B. Rimmer, C. Bilger, Rimmer, P.B., Helling, C., Bilger, C., Ch. Helling   +5 more
core   +1 more source

Molecular Deuterations in Massive Starless Clump Candidates

The Astrophysical Journal Supplement Series
Deuterated molecules are valuable probes for investigating the evolution and the kinematics in the earliest stages of star formation. In this study, we conduct a comprehensive investigation by performing a single-point survey of 101 starless clump ...
Kai Yang, Junzhi Wang, Keping Qiu, Tianwei Zhang   +3 more
doaj   +1 more source

The Barium Star HD204075: Iron Abundance and the Absence of Evidence for Accretion

Journal of Astronomy and Space Sciences, 2019
Spectroscopic observations of barium star ζ Capricornus (HD204075) obtained at the 8.2 m telescope of the European Southern Observatory, with a spectral resolving power R = 80,000 and signal to noise ratio greater than 300, were used to refine the ...
Yeuncheol Jeong, Alexander Yushchenko, Vira Gopka   +2 more
doaj   +1 more source

Out There No One Has a Right to Die

Bioethics, Volume 40, Issue 6, Page 565-572, July 2026.
ABSTRACT The eventual goal of space exploration is to colonize exoplanets and their moons outside our solar system. This is a dangerous and immoral endeavour. The extraterrestrial life forms encountered would be hostile, vulnerable or both, and the descendants of the original pioneers would be involuntarily exposed to hazardous conditions and ...
Matti Häyry
wiley   +1 more source