Results 121 to 130 of about 57,383 (218)

High-resolution Mid-infrared Spectroscopy of SVS13-A with EXES/SOFIA: The Surprisingly High CH3OH/H2O Ratio in the Planet-forming Zone of a Solar Mass Protostar

The Astrophysical Journal Letters
Water and methanol are key components of interstellar ices and gas in star- and planet-forming regions, but direct observations of water in low-mass protostars are challenging due to atmospheric absorption.
Curtis DeWitt, Marta De Simone, Eleonora Bianchi, Cecilia Ceccarelli, Claudio Codella, Sarah Nickerson, Keeyoon Sung, Albert Rimola, Vittorio Bariosco, Piero Uliengo, Naseem Rangwala   +10 more
doaj   +1 more source

Elemental Abundances in the Diffuse Interstellar Medium from Joint Far-ultraviolet and X-Ray Spectroscopy: Iron, Oxygen, Carbon, and Sulfur

The Astronomical Journal
In this study, we investigate interstellar absorption lines along the line of sight toward the galactic low-mass X-ray binary Cygnus X-2. We combine absorption line data obtained from high-resolution X-ray spectra collected with the Chandra and XMM ...
I. Psaradaki, L. Corrales, J. Werk, A. G. Jensen, E. Costantini, M. Mehdipour, R. Cilley, N. Schulz, J. Kaastra, J. A. García, L. Valencic, T. Kallman, F. Paerels   +12 more
doaj   +1 more source

Photocleavage of Aliphatic C–C Bonds in the Interstellar Medium

The Astrophysical Journal
Ultraviolet (UV) processing in the interstellar medium (ISM) induces the dehydrogenation of hydrocarbons. Aliphatics, including alkanes, are present in different interstellar environments, being prevalently formed in evolved stars; thus, the ...
Guillermo Tajuelo-Castilla, Jesús I. Mendieta-Moreno, Mario Accolla, Jesús M. Sobrado, Sofia Canola, Pavel Jelínek, Gary J. Ellis, José Ángel Martín-Gago, Gonzalo Santoro   +8 more
doaj   +1 more source

Measuring Interstellar Carbon Abundance via 158 μm [C ii] Absorption with SOFIA—A Potential Detection and Proof-of-concept for Depletion Studies with Future Far-IR Facilities

The Astronomical Journal
Carbon plays key roles in the interstellar medium (ISM)—as a constituent of dust, as the carrier of the dominant far-infrared (FIR) cooling line, and as a component of various important molecules.
Christopher J. R. Clark, Julia. C. Roman-Duval, Suzanne C. Madden, Marc Mertens, Claire E. Murray, Jürgen Stutzki, Elizabeth Tarantino, Kirill Tchernyshyov   +7 more
doaj   +1 more source

On interstellar Fe X forbidden line absorption toward Cepheus OB2

The Astrophysical Journal, 1984
A weak interstellar absorption line which can be identified as the forbidden line of Fe X 6375 A is observed in the spectrum of the A2 Ia star Nu Cep, which is a member of the Cepheus OB2 association. The equivalent width, width, and radial velocity of the line differ indistinguishably from those of similar absorption previously detected uniquely ...
openaire   +1 more source

The Structure of the Local Interstellar Medium. VII. Additional New Mg ii, Fe ii, and Mn ii Observations toward Stars within 100 pc

The Astrophysical Journal
We present new high-resolution ( R  ∼ 114,000), near-ultraviolet spectra in the direction of 36 nearby (
Azmain H. Nisak, Seth Redfield, Jeffrey L. Linsky, Brian E. Wood, Allison Youngblood   +4 more
doaj   +1 more source

The FAST H i 21 cm Absorption Blind Survey. II. Statistical Exploration for Associated and Intervening Systems

The Astrophysical Journal Supplement Series
We present an extragalactic H i 21 cm absorption lines catalog from a blind search at z ≤ 0.35, using drift-scan data collected in 1325.6 hr by the ongoing Commensal Radio Astronomy Fast Survey and FAST All Sky H i Survey, which spans a sky area of 6072 ...
Wenkai Hu, Yougang Wang, Yichao Li, Wenxiu Yang, Yidong Xu, Fengquan Wu, Ue-Li Pen, Jie Wang, Yingjie Jing, Chen Xu, Qingze Chen, Zheng Zheng, Di Li, Ming Zhu, Xin Zhang, Xuelei Chen   +15 more
doaj   +1 more source

SN Ia 2025bvm in the Seyfert galaxy NGC 4156: Early detection and follow-up observations

Astronomy & Astrophysics
Aims. We investigated the photometric and spectroscopic evolution of SN Ia 2025bvm to perform a detailed classification and provide an independent distance estimate for the host galaxy NGC 4156. Methods.
Tsvetkov D. Yu., Oknyansky V. L., Pavlyuk N. N., Metlov V. G., Chelouche D., Sobrino Figaredo C., Kaspi S., Ikonnikova N. P., Burlak M. A., Belinski A. A., Echeistov V. A., Dodin A. V., Potanin S. A., Shatsky N. I.   +13 more
doaj   +1 more source

Polarization of interstellar molecular radiofrequency absorption lines

The Astrophysical Journal, 1983
N. D. Kylafis, P. R. Shapiro
openaire   +1 more source

Demystifying Strange O vi Line Widths with Hydrodynamic Simulations

The Astrophysical Journal
We present a survey of O vi line widths obtained from hydrodynamic simulations that model the mixing between high-velocity clouds and the circumgalactic medium and track the nonequilibrium ionization populations of the ions.
Chen Wang, Eric Goetz, Robin Shelton
doaj   +1 more source