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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

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

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

We determine the sensitivity to a possible variation of the proton-to-electron mass ratio \mu for torsion-wagging-rotation transitions in the ground state of methylamine (CH3NH2). Our calculation uses an effective Hamiltonian based on a…

The possible cosmological variation of the proton-to-electron mass ratio was estimated by measuring the H_2 wavelengths in the high-resolution spectrum of the quasar Q~0347-382. Our analysis yielded an estimate for the possible deviation of…

天体物理学 · 物理学 2009-11-07 A. Ivanchik , P. Petitjean , E. Rodriguez , D. Varshalovich

Aims. To validate the Einstein equivalence principle (local position invariance) by limiting the fractional changes in the electron-to-proton mass ratio, mu = m_e/m_p, measured in Galactic plane objects. Methods. High resolution spectral…

星系天体物理 · 物理学 2015-06-17 S. A. Levshakov , D. Reimers , C. Henkel , B. Winkel , A. Mignano , M. Centurion , P. Molaro

We estimate sensitivity coefficients Q_\mu to variation of the electron-to-proton mass ratio \mu for microwave transitions in partly deuterated ammonia NH2D and ND2H. Because of the mixing between rotational and inversion degrees of freedom…

原子物理 · 物理学 2010-03-26 M. G. Kozlov , A. V. Lapinov , S. A. Levshakov

The Standard Model of particle physics assumes that the so-called fundamental constants are universal and unchanging. Absorption lines arising in molecular clouds along quasar sightlines offer a precise test for variations in the…

天体物理学 · 物理学 2009-08-18 Michael T. Murphy , Victor V. Flambaum , Sebastien Muller , Christian Henkel

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

We report on new tests that improve our previous (2009-2010) estimates of the electron-to-proton mass ratio variation, mu = m_e/m_p. Subsequent observations (2011-2013) at the Effelsberg 100-m telescope of a sample of eight molecular cores…

宇宙学与河外天体物理 · 物理学 2013-10-02 S. A. Levshakov , C. Henkel , D. Reimers , P. Molaro

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

The variation of the dimensionless fundamental physical constant mu=m_p/m_e can be checked through observation of Lyman and Werner lines of molecular hydrogen in the spectra of distant QSOs. Our intention is to asses the accuracy of the…

宇宙学与河外天体物理 · 物理学 2016-02-03 Martin Wendt , Paolo Molaro

Near (~100 pc) and far (~8.7 kpc) relative to the Galactic center, the molecular clouds SgrB2(N) and Orion-KL exhibit different values of the fundamental physical constant mu=m_e/m_p - the electron-to-proton mass ratio. Measured frequency…

星系天体物理 · 物理学 2025-03-25 J. S. Vorotyntseva , S. A. Levshakov

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

We present a strong constraint on variation of the proton-to-electron mass ratio, mu, over cosmological time scales using molecular hydrogen transitions in optical quasar spectra. Using high quality spectra of quasars Q0405-443, Q0347-383…

天体物理学 · 物理学 2010-05-12 Julian A. King , John K. Webb , Michael T. Murphy , Robert F. Carswell

The possibility of using astrophysical observations of rotational transitions in the methanol molecule to measure, or constrain temporal and spatial variations in the proton-to-electron mass ratio (mu) has recently been investigated by…

宇宙学与河外天体物理 · 物理学 2015-06-03 Simon Ellingsen , Maxim Voronkov , Shari Breen

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

Exotic cosmologies predict variability of the fundamental physical constants over the cosmic time. Using the VLT/UVES high resolution spectra of the quasar Q0347-3819 and unblended electronic - vibrational - rotational lines of the H2…

天体物理学 · 物理学 2014-10-13 S. A. Levshakov , M. Dessauges-Zavadsky , S. D'Odorico , P. Molaro

Transitions in atoms and molecules provide an ideal test ground for constraining or detecting a possible variation of the fundamental constants of nature. In this Perspective, we review molecular species that are of specific interest in the…

化学物理 · 物理学 2015-06-18 Paul Jansen , Hendrick L. Bethlem , Wim Ubachs

Spatial and temporal variations in the electron-to-proton mass ratio, mu, and in the fine-structure constant, alpha, are predicted in non-Standard models aimed to explain the nature of dark energy. Among them the so-called chameleon-like…

宇宙学与河外天体物理 · 物理学 2009-11-20 S. A. Levshakov , I. I. Agafonova , P. Molaro , D. Reimers
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