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相关论文: Methanol as a tracer of fundamental constants

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We report on the using of torsion-rotational transitions in the CH3OH and (13)CH3OH molecules to evaluate possible variations of the physical constant mu=m_e/m_p - the electron-to-proton mass ratio - from spectral observations of emission…

星系天体物理 · 物理学 2024-05-09 J. S. Vorotyntseva , S. A. Levshakov

We present results on numerical calculations of the sensitivity coefficients, Qmu, of microwave molecular transitions in (13C)H3OH and CH3(18O)H to the hypothetical variation in the fundamental physical constant mu - the electron-to-proton…

星系天体物理 · 物理学 2023-11-17 J. S. Vorotyntseva , M. G. Kozlov , S. A. Levshakov

In this paper, we show that methanol (CH3OH) torsional-rotational transitions, which have increased sensitivity to small variations of mu - the electron-to-proton mass ratio, are shifted relative to less sensitive transitions in the…

星系天体物理 · 物理学 2026-03-09 J. S. Vorotyntseva , S. A. Levshakov

Numerical calculations of the sensitivity coefficients, Q_mu, of microwave molecular transitions in the ground torsion-rotation state of deuterated methanol (CH3OD, CD3OH, and CD3OD) to small variations in the fundamental physical constant…

高能物理 - 唯象学 · 物理学 2024-06-18 J. S. Vorotyntseva , S. A. Levshakov , M. G. Kozlov

Torsion-rotation transitions in molecules exhibiting hindered internal rotation possess enhanced sensitivities to a variation of the proton-to-electron mass ratio. This enhancement occurs due to a cancellation of energies associated with…

原子物理 · 物理学 2013-06-06 Paul Jansen , Li-Hong Xu , Isabelle Kleiner , Hendrick L. Bethlem , Wim Ubachs

Recently, methanol was identified as a sensitive target system to probe variations of the proton-to-electron mass ratio $\mu$ [Jansen \emph{et al.} Phys. Rev. Lett. \textbf{106}, 100801 (2011)]. The high sensitivity of methanol originates…

化学物理 · 物理学 2012-03-07 Paul Jansen , Isabelle Kleiner , Li-Hong Xu , Wim Ubachs , Hendrick L. Bethlem

Methanol (CH$_{3}$OH) is a key complex organic molecule (COM) in the interstellar medium, widely used as a tracer of dense gas and hot molecular cores (HMCs). Using high-resolution ALMA observations from the ATOMS survey, we investigate the…

Recently, the extremely sensitive torsion-rotation transitions in methanol have been used to set a tight constraint on a possible variation of the proton-to-electron mass ratio over cosmological time scales. In order to improve this…

Microwave and submillimeter molecular transition frequencies between nearly degenerated rotational levels, tunneling transitions, and mixed tunneling-rotational transitions show an extremely high sensitivity to the values of the…

原子物理 · 物理学 2016-10-26 M. G. Kozlov , S. A. Levshakov

Methanol is an abundant molecule in space. The column density of CH$_3^{18}$OH is in some star-forming regions so high that the search for CH$_3^{17}$OH is promising. But only very few transition frequencies of CH$_3^{17}$OH with a…

星系天体物理 · 物理学 2024-08-28 Holger S. P. Müller , Vadim V. Ilyushin , Arnaud Belloche , Frank Lewen , Stephan Schlemmer

Quantum mechanical tunneling inversion transition in ammonia NH3 is actively used as a sensitive tool to study possible variations of the electron-to-proton mass ratio, mu = m_e/m_p. The molecule H3O+ has the inversion barrier significantly…

宇宙学与河外天体物理 · 物理学 2011-01-27 M. G. Kozlov , S. A. Levshakov

Methanol is observed in a wide range of astrophysical sources throughout the universe, and comprehensive databases of the millimeter and THz spectra of CH3OH and its principal isotopologues represent important tools for the astronomical…

天体物理仪器与方法 · 物理学 2015-06-22 Li-Hong Xu , R. M. Lees , Yun Hao , H. S. P. Mueller , C. P. Endres , F. Lewen , S. Schlemmer , K. M. Menten

Methanol is an important tracer to probe physical and chemical conditions in the interstellar medium of galaxies. Methanol is also the most sensitive target molecule for probing potential space-time variations of the proton-electron mass…

星系天体物理 · 物理学 2021-08-04 S. Muller , W. Ubachs , K. M. Menten , C. Henkel , N. Kanekar

The dependence of the proton-to-electron mass ratio, mu, on the local matter density was investigated using methanol emission in the dense dark cloud core L1498. Towards two different positions in L1498, five methanol transitions were…

宇宙学与河外天体物理 · 物理学 2017-10-18 M. Daprà , C. Henkel , S. A. Levshakov , K. M. Menten , S. Muller , H. L. Bethlem , S. Leurini , A. V. Lapinov , W. Ubachs

We report Karl G. Jansky Very Large Array (VLA) absorption spectroscopy in four methanol (CH$_3$OH) lines in the $z = 0.88582$ gravitational lens towards PKS1830-211. Three of the four lines have very different sensitivity coefficients…

宇宙学与河外天体物理 · 物理学 2015-06-23 N. Kanekar , W. Ubachs , K. M. Menten , J. Bagdonaite , A. Brunthaler , C. Henkel , S. Muller , H. L. Bethlem , M. Dapra

We present a (sub)millimeter line survey of the methanol maser outflow located in the massive star-forming region DR21(OH) carried out with the Submillimeter Array (SMA) at 217/227 GHz and 337/347 GHz. We find transitions from several…

太阳与恒星天体物理 · 物理学 2018-12-26 Ma. T. Orozco-Aguilera , Antonio Hernández-Gómez , Luis A. Zapata

We present results on simultaneous observations of Class~I methanol masers at 25, 36, and 44 GHz towards 22 Galactic targets carried out with the Effelsberg 100-m telescope. The study investigates relations between the hyperfine (HF)…

Ethylene glycol in its ground conformation has tunneling transition with the frequency about 7 GHz. This leads to a rather complicated tunneling-rotational spectrum. Because tunneling and rotational energies have different dependence on the…

原子物理 · 物理学 2015-06-18 A. V. Viatkina , M. G. Kozlov

A limit on a possible cosmological variation of the proton-to-electron mass ratio $\mu$ is derived from methanol (CH$_3$OH) absorption lines in the benchmark PKS1830$-$211 lensing galaxy at redshift $z = 0.89$ observed with the Effelsberg…

宇宙学与河外天体物理 · 物理学 2013-12-11 Julija Bagdonaite , Mario Daprà , Paul Jansen , Hendrick L. Bethlem , Wim Ubachs , Sébastien Muller , Christian Henkel , Karl M. Menten

We report accurate laboratory measurements of selected methanol transition frequencies between 0.834 and 230 GHz in order to facilitate astronomical velocity analyses. New data have been obtained between 10 and 27 GHz and between 60 and 119…

天体物理学 · 物理学 2011-03-02 H. S. P. Mueller , K. M. Menten , H. Maeder
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