Results 51 to 60 of about 877,168 (238)

Interstellar Scintillation and Clouds of the Interstellar Turbulent Plasma [PDF]

open access: yesInternational Astronomical Union Colloquium, 2001
AbstractData on interstellar diffraction and refraction scintillation of pulsars are analyzed. Comparison between theory and the observational data shows that two types of spectra for electron density fluctuations are realized in the interstellar medium: pure power law and piecewise with a break. The distribution of turbulent plasma in the Galaxy has a
openaire   +2 more sources

A Reanalysis of the Carbon Abundance in the Translucent Cloud toward HD 24534 [PDF]

open access: yes, 1998
We have reanalyzed the Goddard High Resolution Spectrograph data set presented by Snow et al. which contains the interstellar intersystem C II] 2325A line through the translucent cloud toward HD 24534 (X Persei). In contrast to the results of Snow et al.,
David M. Meyer   +4 more
core   +2 more sources

The density distribution and 58.4 nm radiation intensity of interstellar helium in the heliosphere: a model simulation

open access: yesEarth and Planetary Physics
Research on the interstellar medium and its interaction with the solar system constitutes a significant topic in planetary physics. As the Sun traverses the local interstellar cloud, interstellar neutrals penetrate the heliosphere, forming the ...
JiaLing Lyu   +3 more
doaj   +1 more source

Composite Single‐Reference and Explicitly Correlated Multireference Calculations on the Mechanism of Pyrrole Pyrolysis

open access: yesJournal of Physical Organic Chemistry, Volume 39, Issue 4, April 2026.
New calculations have been applied to the pyrolysis of pyrrole under shock‐tube conditions and to the radical‐radical reaction between allyl and •CN at low temperature and pressure, using the same mechanistic scheme for both. ABSTRACT The pyrolysis of pyrrole has previously been studied in shock‐tube experiments and in jet‐stirred reactors. The results
Barry K. Carpenter
wiley   +1 more source

Structure and evolution of interstellar carbonaceous dust. Insights from the laboratory

open access: yesFrontiers in Astronomy and Space Sciences, 2022
A large fraction of interstellar carbon is locked up in solid grains. The nature, origin and evolution of these grains have been investigated for decades.
Víctor J. Herrero   +5 more
doaj   +1 more source

First Principles Rovibronic Absorption Spectra of HF Molecule

open access: yesJournal of Computational Chemistry, Volume 47, Issue 6, March 5, 2026.
Hydrogen fluoride (HF) is astrophysically important, as it has been detected in sunspots, Venus, red giants, and the interstellar medium, serving as a probe of exoplanet atmospheres. This article presents an ab initio investigation of HF rovibronic spectroscopy, combining high‐level electronic‐structure data with nuclear‐motion solutions and refinement
Nariman Abu El Kher   +5 more
wiley   +1 more source

Time-variability in the Interstellar Boundary Conditions of the Heliosphere: Effect of the Solar Journey on the Galactic Cosmic Ray Flux at Earth

open access: yes, 2011
During the solar journey through galactic space, variations in the physical properties of the surrounding interstellar medium (ISM) modify the heliosphere and modulate the flux of galactic cosmic rays (GCR) at the surface of the Earth, with consequences ...
A. Yeghikyan   +48 more
core   +1 more source

The Infrared Complex Refractive Index and Band Strengths of Coronene Thin Films

open access: yesThe Astrophysical Journal
Polycyclic aromatic hydrocarbon (PAH) molecules have long been theorized to be present in a multitude of interstellar environments. The radio-frequency detections of specific cyanosubstituted PAH molecules in the Taurus Molecular Cloud have provided new ...
J. E. Roser, L. Jovanović, A. Ricca
doaj   +1 more source

Boron abundances in diffuse interstellar clouds [PDF]

open access: yesProceedings of the International Astronomical Union, 2009
AbstractWe present a comprehensive survey of B abundances in diffuse interstellar clouds from HST/STIS observations along 56 Galactic sight lines. Our sample is the result of a complete search of archival STIS data for the B II λ1362 resonance line, with each detection confirmed by the presence of absorption from other dominant ions at the same ...
Ritchey, A. M.   +3 more
openaire   +2 more sources

Discovery and Initial Investigation of a New Low Surface Brightness Planetary Nebula Candidate at High Galactic Latitude

open access: yesAstronomische Nachrichten, Volume 347, Issue 3, March 2026.
ABSTRACT Planetary nebulae represent a late evolutionary phase of low‐ to intermediate‐mass stars. In this article, we present the serendipitous discovery of a previously unknown, faint potential Galactic planetary nebula (PN) in the constellation Camelopardalis, identified during a survey‐inspection, aiming at the detection of dwarf companions of the ...
W. E. Celnik   +12 more
wiley   +1 more source

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