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Related papers: Proton-electron mass ratio from HD$^+$ revisited

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An almost model-independent parametrization for the ratio of the total cross section to the elastic slope, as function of the center of mass energy, is introduced. The analytical result is based on the approximate relation of this quantity…

High Energy Physics - Phenomenology · Physics 2012-02-02 D. A. Fagundes , M. J. Menon

We study the electromagnetic contribution to the proton-neutron mass splitting by combining lattice simulations and the modified Cottingham sum rule of Walker-Loud, Carlson and Miller. This analysis yields an estimate of the isovector…

Nuclear Theory · Physics 2015-03-05 A. W. Thomas , X. G. Wang , R. D. Young

We summarize and explain the current status of time variations of the electron mass in cosmology, showing that such variations allow for significant easing of the Hubble tension, from the current $\sim5\sigma$ significance, down to between…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-03 Nils Schöneberg , Léo Vacher

Recent polarization transfer measurements of the proton electromagnetic form factors yield very different results from previous Rosenbluth extractions. This inconsistency implies uncertainties in our knowledge of the form factors and raises…

Nuclear Experiment · Physics 2009-11-10 J. Arrington

We discuss that it is quite possible to realize the smooth transition of the universe between a matter/radiation dominated deceleration and a dark energy dominated acceleration, even with a variation of proton-to-electron mass ratio. The…

General Relativity and Quantum Cosmology · Physics 2021-07-14 Soumya Chakrabarti

Vibrational overtones in deeply bound molecules are sensitive probes for variation of the proton-to-electron mass ratio $\mu$. In nonpolar molecules, these overtones may be driven as two-photon transitions. Here, we present procedures for…

Atomic Physics · Physics 2019-01-03 Ryan Carollo , Alexander Frenett , David Hanneke

The impact of higher-order final-state photonic corrections on the precise determination of the W-boson mass at the Tevatron and LHC colliders is evaluated. In the presence of realistic selection criteria, the shift in the W mass from a fit…

High Energy Physics - Phenomenology · Physics 2009-11-10 C. M. Carloni Calame , G. Montagna , O. Nicrosini , M. Treccani

We report the results of a new Rosenbluth measurement of the proton form factors at Q^2 values of 2.64, 3.20 and 4.10 GeV^2. Cross sections were determined by detecting the recoiling proton in contrast to previous measurements in which the…

Context. Molecular hydrogen and its cation H+2 are among the first species formed in the early Universe, and play a key role in the thermal and chemical evolution of the primordial gas. In molecular clouds, H+2 ions formed through…

Absorption lines of H$_2$ and HD molecules observed at high redshift in the line of sight towards quasars are a test ground to search for variation of the proton-to-electron mass ratio $\mu$. For this purpose, results from astronomical…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-13 W. Ubachs , E. J. Salumbides , M. T. Murphy , H. Abgrall , E. Roueff

Molecular hydrogen (H2) absorption features observed in the line-of-sight to Q2348-011 at redshift zabs = 2.426 are analysed for the purpose of detecting a possible variation of the proton-to-electron mass ratio mu=mp/me. By its structure…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Julija Bagdonaite , Michael T. Murphy , Lex Kaper , Wim Ubachs

The collision-energy resolved rate coefficient for dissociative recombination of HD+ ions in the vibrational ground state is measured using the photocathode electron target at the heavy-ion storage ring TSR. Rydberg resonances associated…

The systematic shifts of the transition frequencies in the molecular hydrogen ions are of relevance to ultra-high-resolution radio-frequency, microwave and optical spectroscopy of these systems, performed in ion traps. We develop the…

Atomic Physics · Physics 2015-06-16 Dimitar Bakalov , Stephan Schiller

A procedure is described for the precise nonrelativistic evaluation of the dipole polarizabilities of H_2^+ and D_2^+ that avoids any approximation based on the size of the electron mass relative to the nucleus mass. The procedure is…

Atomic Physics · Physics 2007-05-23 J. M. Taylor , A. Dalgarno , J. F. Babb

A non-moving electron hydrogen model is proposed, resolving a long standing contradiction (94 years) in the hydrogen atom. This, however, forces to not use the "in an orbit point particle kinetic energy" as the phenomenon responsible for…

General Physics · Physics 2007-05-23 Omar Yepez

The extremely narrow natural linewidths of rovibrational energy levels in the molecular hydrogen ion $\textrm{H}_2^{\,+}$, and the prospect of synthesising its antimatter counterpart $\overline{\textrm{H}}_2^{\,-}$, make it a promising…

Atomic Physics · Physics 2026-04-20 Graham M. Shore

We discuss recent experimental results concerning the cross section ratio of positron over electron elastic scattering on protons, and compare with the predictions of a pre-existent calculation. The deviation from unity of this ratio,…

High Energy Physics - Phenomenology · Physics 2019-02-27 V. V. Bytev , E. Tomasi-Gustafsson

The ratio of the proton's elastic electromagnetic form factors $G_{Ep}/G_{Mp}$ was obtained by measuring $P_{t}$ and $P_{\ell}$, the transverse and longitudinal recoil proton polarization, respectively. For the elastic reaction $\vec e p…

Background: Measurements of exclusive meson production are a useful tool in the study of hadronic structure. In particular, one can discern the relevant degrees of freedom at different distance scales through these studies. Purpose: To…

Spectroscopy of hydrogen can be used for a search into physics beyond the Standard Model. Differences between the absorption spectra of H$_2$ as observed at high redshift and those measured in the laboratory can be interpreted in terms of…

Atomic Physics · Physics 2017-08-23 Wim Ubachs , Jeroen C. J. Koelemeij , Kjeld S. E. Eikema , Edcel J. Salumbides