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Related papers: Modelling CH$_3$OH masers: Sobolev approximation a…

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The collisional pumping of H$_2$O and CH$_3$OH masers in magnetohydrodynamic nondissociative C-type shocks is considered. A grid of C-type shock models with speeds in the range $5-70$ km s$^{-1}$ and preshock gas densities $n_{\rm H_2,0} =…

Astrophysics of Galaxies · Physics 2022-08-02 A. V. Nesterenok

We have carried out a multi-epoch simultaneous survey of 22 GHz H$_2$O and 44 GHz Class I CH$_3$OH masers toward 103 ultracompact HII regions (UCHIIs) between 2010 and 2017. We detected H$_2$O and CH$_3$OH maser emission in 74 (72%) and 55…

Solar and Stellar Astrophysics · Physics 2019-09-04 Won-Ju Kim , Kee-Tae Kim , Kwang-Tae Kim

The collisional excitation of methanol molecule in non-dissociative magnetohydrodynamic shock waves is considered. All essential chemical processes that determine methanol abundance in the gas are taken into account in the shock model. The…

Astrophysics of Galaxies · Physics 2022-01-05 A. V. Nesterenok

We report a multi-epoch, simultaneous 22 GHz H2O and 44 GHz class I CH3OH maser line survey towards 180 intermediate-mass young stellar objects, including 14 Class 0, 19 Class I objects, and 147 Herbig Ae/Be stars. We detected H2O and CH3OH…

Astrophysics of Galaxies · Physics 2015-05-30 Jae-Han Bae , Kee-Tae Kim , So-Young Youn , Won-Ju Kim , Do-Young Byun , Hyunwoo Kang , Chung Sik Oh

We report on a large 44 GHz ($7_0-6_1$ A$^+$) methanol (CH$_3$OH) maser survey of the Galactic Center (GC). The Karl G. Jansky Very Large Array was used to search for CH$_3$OH maser emission covering a large fraction of the region around…

Solar and Stellar Astrophysics · Physics 2016-12-07 Bridget McEwen , Loránt Sjouwerman , Ylva Pihlström

The collisional pumping of CH3OH and OH masers in non-dissociative C-type shock waves is studied. The chemical processes responsible for the evolution of molecule abundances in the shock wave are considered in detail. The large velocity…

Astrophysics of Galaxies · Physics 2021-12-15 A. V. Nesterenok

We have used the Karl G. Jansky Very Large Array (VLA) to search for 36 GHz and 44 GHz methanol (CH3OH) lines in a sample of 21 Galactic supernova remnants (SNRs). Mainly the regions of the SNRs with 1720 MHz OH masers were observed.…

Astrophysics of Galaxies · Physics 2015-06-18 Y. M. Pihlström , L. O. Sjouwerman , D. A. Frail , M. J. Claussen , R. A. Mesler , B. C. McEwen

We report simultaneous single-dish surveys of 22 GHz H2O and 44 and 95 GHz class I CH3OH masers toward 299 Red MSX Sources in the protostellar stage. The detection rates are 45% at 22 GHz, 28% at 44 GHz, and 23% at 95 GHz. There are 15, 53,…

Astrophysics of Galaxies · Physics 2018-05-23 Chang-Hee Kim , Kee-Tae Kim , Yong-Sun Park

We present results from calculations of the physical conditions necessary for the occurrence of 36.169 ($4_{-1}-3_{0}\, E$), 44.070 ($7_{0}-6_{1}\,A^+$), 84.521 ($5_{-1}-4_{0}\,E$), and 95.169 ($8_{0}-7_{1}\,A^+$) GHz methanol (CH$_3$OH)…

Solar and Stellar Astrophysics · Physics 2015-06-22 Bridget C. McEwen , Ylva M. Pihlström , Loránt O. Sjouwerman

We discuss advanced statistical methods to improve parameter estimation of nuclear models. In particular, using the Liquid Drop Model for nuclear binding energies, we show that the area around the global $\chi^2$ minimum can be efficiently…

Nuclear Theory · Physics 2018-11-26 M. Shelley , P. Becker , A. Gration , A. Pastore

We present the first detection of a 6.7 GHz Class II methanol (CH3OH) maser in the Andromeda galaxy (M31). The CH3OH maser was found in a Very Large Array (VLA) survey during the fall of 2009. We have confirmed the methanol maser with the…

Astrophysics of Galaxies · Physics 2015-05-20 Lorant O. Sjouwerman , Claire E. Murray , Ylva M. Pihlstrom , Vincent L. Fish , Esteban D. Araya

Among the tracers of the earliest phases in the massive star formation process, methanol masers have gained increasing importance. The phenomenological distinction between Class I and II methanol masers is based on their spatial association…

Astrophysics of Galaxies · Physics 2015-05-18 F. Fontani , R. Cesaroni , R. S. Furuya

Methanol masers which are traditionally divided into two classes provide possibility to study important parts of the star forming regions: Class~II masers trace vicinities of the massive YSOs while class~I masers are likely to trace more…

A two level sampling method is applied to variational Monte Carlo (VMC) that samples the one and two body parts of the wave function separately. The method is demonstrated on a single Li_2 molecule in free space and 32 H_2 molecules in a…

Computational Physics · Physics 2016-09-08 Mark Dewing

Progress in computing various meson-baryon scattering amplitudes is presented on a single ensemble from the Coordinated Lattice Simulations (CLS) consortium with $m_\pi=200$ MeV and $N_f=2+1$ dynamical fermions. The finite-volume L\"uscher…

High Energy Physics - Lattice · Physics 2021-11-16 Colin Morningstar , John Bulava , Andrew D. Hanlon , Ben Hörz , Daniel Mohler , Amy Nicholson , Sarah Skinner , André Walker-Loud

Very long baseline interferometry (VLBI) monitoring of the 6.7 GHz methanol maser allows us to measure the internal proper motions of the maser spots and therefore study the gas motion around high-mass young stellar objects. To this end, we…

We report the detection of the millimeter CH$_3$OH masers including a new detection of class I (11$_{0,11}$-10$_{1,10}$A) and class II (6$_{1,5}$-5$_{2,4}$E) maser transitions toward the high-mass protostar S255IR NIRS3 in post-burst phase.…

Solar and Stellar Astrophysics · Physics 2023-09-06 Giseon Baek , Jeong-Eun Lee , Neal J. Evans , Tomoya Hirota , Yuri Aikawa , Ji-hyun Kang , Jungha Kim , Jes K. Jørgensen

{The variability study of 6.7\,GHz methanol masers has become a useful way to improve our understanding of the physical conditions in high-mass star-forming regions.} {Based on the single-dish monitoring using the Irbene telescopes, we…

Astrophysics of Galaxies · Physics 2023-07-10 A Aberfelds , A Bartkiewicz , M Szymczak , J Šteinbergs , G Surcis , A Kobak , M Durjasz , I Shmeld

Bio-image analysis is challenging due to inhomogeneous intensity distributions and high levels of noise in the images. Bayesian inference provides a principled way for regularizing the problem using prior knowledge. A fundamental choice is…

Computer Vision and Pattern Recognition · Computer Science 2014-03-04 Ivo F. Sbalzarini , Sophie Schneider , Janick Cardinale

When modeling physical properties of molecules with machine learning, it is desirable to incorporate $SO(3)$-covariance. While such models based on low body order features are not complete, we formulate and prove general completeness…

Machine Learning · Computer Science 2024-09-05 Hartmut Maennel , Oliver T. Unke , Klaus-Robert Müller
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