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Related papers: Hyperfine structure of methanol lines at 25 GHz

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Methyl formate in its first torsionally excited state (vt=1 at 131 cm-1) is detected for the first time toward W51 e2. All transitions from excited methyl formate within the observed spectral range are actually detected (82 transitions) and…

Astrophysics · Physics 2009-11-13 Karine Demyk , Georges Wlodarczak , Miguel Carvajal

We present the results from arcsecond resolution observations of various line transitions at 1.3 mm toward hypercompact HII region G28.20-0.04N. With the SMA data, we have detected and mapped the transitions in the CH$_{3}$CN, CO,…

Astrophysics · Physics 2009-11-13 Sheng-Li Qin , Maohai Huang , Yuefang Wu , Rui Xue , Sheng Chen

We have used the Australia Telescope Compact Array (ATCA) to undertake the first high angular resolution observations of 37.7-GHz ($7_{-2} - 8_{-1}E$) methanol masers towards a sample of eleven high-mass star formation regions which host…

Astrophysics of Galaxies · Physics 2018-08-15 Simon Ellingsen , Maxim Voronkov , Shari Breen , Jim Caswell , Andrej Sobolev

A survey of 27 galactic star-forming regions in the 6_K-5_K, 5_K-4_K, and 8_K-7_K CH3CN lines at 110, 92, and 147 GHz, respectively, is made. Twenty-five sources are detected at 110 GHz, nineteen at 92 GHz, and three at 147 GHz. The…

Astrophysics · Physics 2009-10-31 S. V. Kalenskii , V. G. Promislov , A. V. Alakoz , A. Winnberg , L. E. B. Johansson

A two-step, two-color laser spectroscopy technique has been used to measure the hyperfine splitting of the 7p$_{1/2}$ excited state in $^{203}$Tl and $^{205}$Tl, as well as the isotope shift within the 7s$_{1/2}$ - 7p$_{1/2}$ transition.…

Atomic Physics · Physics 2015-06-17 G. Ranjit , D. Kealhofer , G. D. Vukasin , P. K. Majumder

We report on preliminary results from a systematic study of the hyperfine (HF) structure of antiprotonic helium. This precise measurement which was commenced in 2006, has now been completed. Our initial analysis shows no apparent density or…

Atomic Physics · Physics 2015-05-13 T. Pask

We report the detection of bursts of 6.7 GHz methanol maser emission in a high-mass star-forming region, G33.64-0.21. One of the spectral components of the maser in this source changed its flux density by 7 times that of the previous day,…

We present first-principles calculations of the electronic band structure and spin-orbit effects in graphene functionalized with methyl molecules in dense and dilute limits. The dense limit is represented by a 2$\times$2 graphene supercell…

Mesoscale and Nanoscale Physics · Physics 2016-01-27 Klaus Zollner , Tobias Frank , Susanne Irmer , Martin Gmitra , Denis Kochan , Jaroslav Fabian

A non-LTE radiative transfer treatment of cis-methyl formate (HCOOCH3) rotational lines is presented for the first time using a set of theoretical collisional rate coefficients. These coefficients have been computed in the temperature range…

Astrophysics of Galaxies · Physics 2015-06-18 Alexandre Faure , Anthony J. Remijan , Krzysztof Szalewicz , Laurent Wiesenfeld

We present observations of the H91$\alpha$ recombination line emission towards a sample of nine HII regions associated with 6.7-GHz methanol masers, and report arcsecond-scale emission around compact cores. We derive physical parameters for…

Astrophysics · Physics 2009-11-11 Stanislav Shabala , Simon Ellingsen , Stan Kurtz , Larry Forbes

Positronium is an ideal system for the research of QED in the bound state. The hyperfine splitting of positronium (Ps-HFS: about 203 GHz) is a good tool to test QED and also sensitive to new physics beyond the Standard Model. Previous…

Instrumentation and Detectors · Physics 2010-12-01 Akira Miyazaki

In the early days of methanol maser discoveries the 9(2)-10(1) A+ transition at 23.1 GHz was found to exhibit maser characteristics in the northern star-forming region W3(OH), and probable maser emission in two other sources. Attention…

Astrophysics · Physics 2009-11-10 D. M. Cragg , A. M. Sobolev , J. L. Caswell , S. P. Ellingsen , P. D. Godfrey

The ground state hyperfine splitting of positronium, $\Delta_{\mathrm{HFS}}$, is sensitive to high order corrections of QED. A new calculation up to $\mathrm{O}(\alpha ^3 \ln \alpha)$ has revealed a $3.9\sigma$ discrepancy between the QED…

High Energy Physics - Experiment · Physics 2010-05-03 A. Ishida , G. Akimoto , Y. Sasaki , T. Suehara , T. Namba , S. Asai , T. Kobayashi , H. Saito , M. Yoshida , K. Tanaka , A. Yamamoto

Some experimental evidences for methane are produced that the simple transition from frequency scanning of nonlinear-optical resonances to magnetic one may be accompanied with transition from sub-Doppler collisionally broadened structure to…

Chemical Physics · Physics 2009-11-10 K. I. Gus'kov , V. I. Kovalevsky , A. G. Rudavets , E. G. Saprykin

Iram 30-m Observations towards eight protostellar outflow sources were taken in the 96-\SI{176}{\giga\hertz} range. Transitions of CH$_3$OH and CH$_3$CHO were detected in seven of them. The integrated emission of the transitions of each…

We investigate the kinematics of high mass protostellar objects within the high mass star forming region IRAS 19410+2336. We performed high angular resolution observations of 6.7-GHz methanol and 22 GHz water masers using the MERLIN…

Astrophysics of Galaxies · Physics 2021-05-25 M. S. Darwish , K. A. Edris , A. M. S. Richards , S. Etoka , M. S. Saad , M. M. Beheary , G. A Fuller

We report new experimental hyperfine structure (HFS) constants of neutral and singly ionized scandium (Sc I and Sc II). We observed spectra of Sc-Ar and Sc-Ne hollow cathode discharges in the region 200-2500 nm (50,000-4000 cm$^{-1}$) using…

Atomic Physics · Physics 2022-09-26 Hala , G. Nave

The results of interferometric observations of the star-forming region S255IR in the frequency range 210--250 GHz are presented. The observations were carried out with the antenna array SMA (Hawaii, USA). Fifty-three molecules were…

Astrophysics of Galaxies · Physics 2026-02-17 E. A. Mikheeva , S. V. Kalenskii , S. -Y. Liu , A. M. Sobolev , S. Kurtz

We present LVG and non-local radiative transfer calculations involving the rotational and hyperfine structure of the spectrum of N$_2$H$^+$ with collisional rate coefficients recently derived by us. The goal of this study is to check the…

Astrophysics · Physics 2008-11-26 F. Daniel , J. Cernicharo , M. -L. Dubernet

Recent high-dispersion spectroscopy from ground-based telescopes and high-precision spectroscopy from space observatories have enabled atmospheric observations of substellar objects, such as brown dwarfs and hot gaseous exoplanets, with…

Earth and Planetary Astrophysics · Physics 2025-03-31 Ko Hosokawa , Takayuki Kotani , Hajime Kawahara , Yui Kawashima , Kento Masuda , Aoi Takahashi , Kazuo Yoshioka