Results 21 to 30 of about 1,222 (137)

Metal-enriched Neutral Gas Reservoir around a Strongly Lensed Low-mass Galaxy at z = 4 Identified by JWST/NIRISS and VLT/MUSE

The Astrophysical Journal Letters, 2023
Direct observations of low-mass, low-metallicity galaxies at z ≳ 4 provide an indispensable opportunity for detailed inspection of the ionization radiation, gas flow, and metal enrichment in sources similar to those that reionized the universe. Combining
Xiaojing Lin, Zheng Cai, Siwei Zou, Zihao Li, Zuyi Chen, Fuyan Bian, Fengwu Sun, Yiping Shu, Yunjing Wu, Mingyu Li, Jianan Li, Xiaohui Fan, J. Xavier Prochaska, Daniel Schaerer, Stephane Charlot, Daniel Espada, Miroslava Dessauges-Zavadsky, Eiichi Egami, Daniel Stark, Kirsten K. Knudsen, Gustavo Bruzual, Jacopo Chevallard   +21 more
doaj   +1 more source

Vibrationally Resolved Absorption and Fluorescence Cross Sections of Adamantane in the Far-ultraviolet Spectral Range on an Absolute Scale

The Astrophysical Journal Supplement Series, 2023
High-resolution absorption, dispersed fluorescence emission, and photoionization cross sections are presented for gas-phase adamantane excited by synchrotron radiation in the exciting-photon energy range of 6–30 eV. Relative and absolute absorption cross
Lutz Marder, Alexander Breier, Nelson de Oliveira, Philipp Reiss, Philipp Schmidt, Christian Ozga, Catmarna Küstner-Wetekam, Thomas Giesen, Laurent Nahon, Andreas Hans, André Knie, Arno Ehresmann   +11 more
doaj   +1 more source

VUV and mid‐UV photoabsorption cross sections of thin films of glycine and alanine: Application to their photochemistry in the solar system

Photochemistry and Photobiology, EarlyView.
Thin solid films of pure glycine or alanine (thicknesses ranging from 10 to 700 nm) were prepared on MgF2 windows using a vacuum sublimation/recondensation method. VUV‐UV spectroscopy of these films enabled us to characterize new absorption cross sections for glycine and alanine for VUV‐UV radiations between 120 and 300 nm.
Juliette Pastore, Hervé Cottin, Kafila Saïagh, Jodie Belilla, Fabien Stalport, Nicolas Fray, Nathalie Carrasco   +6 more
wiley   +1 more source

CLASSY VII Lyα Profiles: The Structure and Kinematics of Neutral Gas and Implications for LyC Escape in Reionization-era Analogs

The Astrophysical Journal, 2023
Ly α line profiles are a powerful probe of interstellar medium (ISM) structure, outflow speed, and Lyman-continuum escape fraction. In this paper, we present the Ly α line profiles of the Cosmic Origins Spectrograph (COS) Legacy Archive Spectroscopic ...
Weida Hu, Crystal L. Martin, Max Gronke, Simon Gazagnes, Matthew Hayes, John Chisholm, Timothy Heckman, Matilde Mingozzi, Namrata Roy, Peter Senchyna, Xinfeng Xu, Danielle A. Berg, Bethan L. James, Daniel P. Stark, Karla Z. Arellano-Córdova, Alaina Henry, Anne E. Jaskot, Nimisha Kumari, Kaelee S. Parker, Claudia Scarlata, Aida Wofford, Ricardo O. Amorín, Naunet Leonhardes-Barboza, Jarle Brinchmann, Cody Carr, Alessandra Aloisi   +25 more
doaj   +1 more source

Regarding the Detection of Interstellar C4 and C5 Molecules

The Astrophysical Journal
Analysis of very high signal-to-noise ratio (S/N) spectra of reddened stars allowed us to determine an upper limit (UL) of the column density N (C _4 ).
G. A. Galazutdinov, E. I. Kazanina, J. Krełowski   +2 more
doaj   +1 more source

Optical Radiation Pressure: Resonant Mechanical Excitation of Thin Films

Annalen der Physik, Volume 538, Issue 10, October 2026.
The modulation of a laser beam generates a modulated radiation pressure force acting on a thin film. A resonant response is observed, leading to a net average thinning of the film. ABSTRACT Optical radiation pressure was directly observed for the first time more than a century ago.
Janine Emile, Olivier Emile
wiley   +1 more source

Investigating interstellar dust along the line of sight of GX 13+1 using different dust-size distributions

Astronomy & Astrophysics
Context. High-resolution X-ray spectroscopy offers a powerful tool to investigate the physical and chemical properties of dust grains, especially through the analysis of absorption edges of elements such as oxygen, magnesium, silicon, and iron, which are
Vaia B., Zeegers S. T., Abril-Cabezas I., Costantini E.   +3 more
doaj   +1 more source

Influence of Dynamical Friction on the Unstable Manifolds of Lagrange Points in Barred Galaxies

Astronomische Nachrichten, Volume 347, Issue 8, October 2026.
ABSTRACT Some time ago the idea has been proposed that rings and spirals in barred galaxies are shaped by the unstable manifolds of the Lagrange points sitting near the ends of the bar. The topic of the present article is an investigation of whether the numerical support for this suggestion can be improved by the inclusion of dynamical friction into ...
Christof Jung
wiley   +1 more source

Mapping Our Path through the Local Interstellar Medium: High-resolution Ultraviolet Absorption Spectroscopy of Sight Lines along the Sun’s Historical Trajectory

The Astrophysical Journal
Using high-resolution UV data obtained from the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope, we focus on eight sight lines along the Sun’s historical trajectory to reconstruct the morphology of our most recent interstellar ...
Hunter Vannier, Seth Redfield, Brian E. Wood, Hans-Reinhard Müller, Jeffrey L. Linsky, Priscilla C. Frisch   +5 more
doaj   +1 more source

Chemical Kinetics of 2‐, 4‐, and 2,4‐Seleno‐Uracils at Low Temperatures: Tautomerizations and Rotamerizations on Inert Matrices

International Journal of Chemical Kinetics, Volume 58, Issue 10, Page 881-889, October 2026.
ABSTRACT In the interstellar medium, chemical reactions proceed under conditions vastly different to those on Earth; these include extremely low temperatures and densities and take place in the gas phase and on water–ice grains. Understanding the energetics and more importantly the kinetics of such reactions is of relevance to the consequences on how ...
Judith Wurmel, John M. Simmie
wiley   +1 more source