Results 81 to 90 of about 52,443 (248)

Overtone Transition 2ν1 of HCO+ and HOC+: Origin, Radiative Lifetime, Collisional Quenching

ChemPhysChem, Volume 25, Issue 21, November 4, 2024.
The C−H/O−H stretch vibration overtone of one of the simplest molecular ion isomeric systems HCO+/HOC+ is studied in a cryogenic ion trap experiment. Moreover, our comprehensive “zero background” method enables the determination of radiative lifetimes and select quenching reaction rates at the same time.
Miguel Jiménez‐Redondo, Liliia Uvarova, Petr Dohnal, Miroslava Kassayová, Paola Caselli, Pavol Jusko   +5 more
wiley   +1 more source

The Orientation of the Local Interstellar Magnetic Field

, 2007
The orientation of the local interstellar magnetic field introduces asymmetries in the heliosphere that affect the location of heliospheric radio emissions and the streaming direction of ions from the termination shock of the solar wind.
Gombosi, T. I., Opher, M., Stone, E. C.
core   +1 more source

Submillimeterwave Spectroscopy of and Interstellar Search for Nitrosomethane: CH3NO

The Astrophysical Journal
New measurements of nitrosomethane (CH _3 NO), a formamide isomer, were done up to 660 GHz. The molecule exhibits internal rotation motion from the CH _3 group, and therefore the analysis with a dedicated rho-axis method code, RAM36, was used. A total of
Laurent Margulès, Zachary T. P. Fried, Alex N. Byrne, Brett A. McGuire, Luyao Zou, Roman A. Motiyenko, J.-C. Guillemin   +6 more
doaj   +1 more source

Emergence of Optical Activity and Surface Morphology Changes in Racemic Amino Acid Films Under Circularly Polarized Lyman‐α Light Irradiation

Chirality, Volume 36, Issue 11, November 2024.
The photoreaction induced by Lyman‐α circularly polarized light (CPL) irradiation in racemic alanine film is more complex than simple preferential photolysis of enantiopure alanine molecules, and formation of larger molecules is observed. Circular networks of order of 100 nm scale are introduced in the alanine film surface by the irradiation.
Masahiro Kobayashi, Jun‐ichi Takahashi, Hiroshi Ota, Koichi Matsuo, Mohamed I. A. Ibrahim, Taketoshi Minato, Gen Fujimori, Masahiro Katoh, Kensei Kobayashi, Yoko Kebukawa, Hiroaki Nakamura   +10 more
wiley   +1 more source

Nearby Supernova and Cloud Crossing Effects on the Orbits of Small Bodies in the Solar System

The Astrophysical Journal Letters
Supernova (SN) blasts envelop many surrounding stellar systems, transferring kinetic energy to small bodies in the systems. Geologic evidence from ^60 Fe points to recent nearby SN activity within the past several Myr.
Leeanne Smith, Jesse A. Miller, Brian D. Fields   +2 more
doaj   +1 more source

Abundances in Diffuse Interstellar Clouds [PDF]

Highlights of Astronomy, 1980
Interstellar clouds are concentrations of cold (T ≲ 100 K) neutral gas (cf. Spitzer 1978) which are immersed within an intercloud medium. It is worthwhile to distinguish between diffuse clouds (roughly those with E[B-V] ≳ 0.5) and dark clouds (those with E[B-V] ≳ 0.5). This distinction is useful in the sense that diffuse clouds are relatively warm (T ∼
openaire   +1 more source

Probing the range of applicability of structure‐ and energy‐adjusted QM/MM link bonds III: QM/MM MD simulations of solid‐state systems at the example of layered carbon structures

Journal of Computational Chemistry, Volume 45, Issue 26, Page 2186-2197, October 5, 2024).
The QM/MM simulation protocol involving carbonic link bonds was extended for the treatment of layered carbon structures to study the adsorption and intercalation properties of graphitic materials. Abstract The previously introduced workflow to achieve an energetically and structurally optimized description of frontier bonds in quantum mechanical ...
Felix R. S. Purtscher, Thomas S. Hofer
wiley   +1 more source

The Effect of an Inert Solid Reservoir on Molecular Abundances in Dense Interstellar Clouds

Open Astronomy, 2012
The question, what is the role of freeze-out of chemical species in determining the molecular abundances in the interstellar gas is a matter of debate.
Kalvāns Juris, Shmeld Ivar
doaj   +1 more source

Theoretical Calculations for the Acidity of Cyanopolyynes HC2n+1N (n = 0–5) in Gas and Aqueous Phases Using Ab initio Methods

ARO-The Scientific Journal of Koya University, 2019
Cyanopolyynes have been found in the interstellar medium, cold dust cloud Taurus Molecular Cloud-1, and the Titan’s atmosphere. Theoretical calculations are carried out to predict gas and aqueous phase acidities of a series of cyanopolyynes acids.
Hassan H. Abdallah
doaj   +1 more source

Toward an efficient second‐order method for computing the surface gravitational potential on spherical‐polar meshes

Astronomische Nachrichten, Volume 345, Issue 8, October 2024.
Abstract Astrophysical accretion discs that carry a significant mass compared with their central object are subject to the effect of self‐gravity. In the context of circumstellar discs, this can, for instance, cause fragmentation of the disc gas, and—under suitable conditions—lead to the direct formation of gas‐giant planets.
Oliver Gressel, Udo Ziegler
wiley   +1 more source