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Accepted values of the masses of several subatomic particles have been under debate since recent measurements in Penning traps produced more precise yet incompatible results, implying possible inconsistencies in closely related physical…

We report on a new test of Lorentz invariance performed by comparing the resonance frequencies of two orthogonal cryogenic optical resonators subject to Earth's rotation over 1 year. For a possible anisotropy of the speed of light c, we…

Classical Physics · Physics 2008-11-26 Holger Mueller , Sven Herrmann , Claus Braxmaier , Stephan Schiller , Achim Peters

After six years of continuous observations in space, the Alpha Magnetic Spectrometer experiment has released new data on the temporal evolution of the proton and helium fluxes in cosmic rays. These data revealed that the ratio between…

High Energy Astrophysical Phenomena · Physics 2018-12-24 Nicola Tomassetti , Fernando Barão , Bruna Bertucci , Emanuele Fiandrini , José Figueiredo , João Barreira , Miguel Orcinha

One of the fundamental issues in cosmic ray physics is to explain the nature of cosmic ray acceleration and propagation mechanisms. Thanks to the precise cosmic ray data measured by recent space experiments, we are able to investigate the…

High Energy Astrophysical Phenomena · Physics 2022-09-20 Yu Wang , Juan Wu , Wei-Cheng Long

A robust variational approach is used to investigate the sensitivity of the rotation-vibration spectrum of phosphine (PH$_3$) to a possible cosmological variation of the proton-to-electron mass ratio, $\mu$. Whilst the majority of computed…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-17 Alec Owens , Sergei N. Yurchenko , Vladimir Špirko

A new equation of motion, which is derived previously by imposing Neumann boundary condition on cosmological perturbation equations (Shenavar 2016 a), is investigated. By studying the precession of perihelion, it is shown that the new…

Astrophysics of Galaxies · Physics 2019-09-04 Hossein Shenavar

Faraday rotation measures (RMs) of extragalactic radio sources provide information on line-of-sight magnetic fields, including contributions from our Galaxy, source environments, and the intergalactic medium (IGM). Looking at differences in…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-26 T. Vernstrom , B. Gaensler , L. Rudnick , H. Andernach

Accurate spectroscopic measurements of calculable systems provide a powerful method for testing the Standard Model and extracting fundamental constants. Recently, spectroscopic measurements of finite nuclear size effects in normal and…

Atomic Physics · Physics 2023-06-06 Y. van der Werf , K. Steinebach , R. Jannin , H. L. Bethlem , K. S. E. Eikema

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…

Atomic Physics · Physics 2010-03-26 M. G. Kozlov , A. V. Lapinov , S. A. Levshakov

A measurement of the Lamb shift of 49,881.88(76) GHz in muonic hydrogen in conjunction with theoretical estimates of the proton structure effects was recently used to deduce an accurate but rather small radius of the proton. Such an…

High Energy Physics - Phenomenology · Physics 2015-06-04 N. G. Kelkar , F. Garcia Daza , M. Nowakowski

We report tests of local position invariance based on measurements of the ratio of the ground state hyperfine frequencies of 133Cs and 87Rb in laser-cooled atomic fountain clocks. Measurements extending over 14 years set a stringent limit…

Astrophysical tests of the stability of Nature's fundamental couplings are a key probe of the standard paradigms in fundamental physics and cosmology. In this report we discuss updated constraints on the stability of the fine-structure…

High Energy Physics - Phenomenology · Physics 2015-08-26 S. M. João , C. J. A. P. Martins , I. S. A. B. Mota , P. M. T. Vianez

We compare the long-term fractional frequency variation of four hydrogen masers that are part of an ensemble of clocks comprising the National Institute of Standards and Technology,(NIST), Boulder, timescale with the fractional frequencies…

General Relativity and Quantum Cosmology · Physics 2018-02-21 Neil Ashby , Thomas E. Parker , Bijunath R. Patla

Studies of the abundances of deuterium in different astrophysical sites are of fundamental importance to answering the question about how much deuterium was produced during big bang nucleosynthesis and what fraction of it was destroyed…

HC$_3$N is an ubiquitous molecule in interstellar environments, from external galaxies, to Galactic interstellar clouds, star forming regions, and planetary atmospheres. Observations of its rotational and vibrational transitions provide…

The "proton radius puzzle" was recently solved by reducing the four-standard deviation discrepancy between the results for electronic hydrogen ($H$) and muonic hydrogen ($\mu H$) atoms to $3.3$ value. The value of the root-mean-square…

Atomic Physics · Physics 2021-03-30 D. Solovyev , T. Zalialiutdinov , A. Anikin

We propose a high precision satellite experiment to further test Einstein's General Relativity and constrain extended theories of gravity. We consider the frequency shift of a photon radially exchanged between two observers located on Earth…

General Relativity and Quantum Cosmology · Physics 2020-03-18 Luca Buoninfante , Gaetano Lambiase , Antonio Stabile

We present results of interferometric polarization observations of the recently discovered magnetar J1745-2900 in the vicinity of the Galactic center. The observations were made with the Karl G. Jansky Very Large Array (VLA) on 21 February…

Astrophysics of Galaxies · Physics 2016-05-13 E. V. Kravchenko , W. D. Cotton , F. Yusef-Zadeh , Y. Y. Kovalev

The measurement by Pohl et al. [1] of the 2S_1/2^F=1 to 2P_3/2^F=2 transition in muonic hydrogen and the subsequent analysis has led to a conclusion that the rms charge radius of the proton differs from the accepted (CODATA [2]) value by…

Atomic Physics · Physics 2015-05-28 J. D. Carroll , A. W. Thomas , J. Rafelski , G. A. Miller

We present Faraday Rotation Measure (RM) properties of seven active galactic nuclei (AGN), observed with the NRAO VLA at three epochs in 2012-2014. Data was taken at 1.4, 2.2, 5.0, 8.2, 15.4, 22.4, 33.5 and 43.1 GHz quasi simultaneously in…

High Energy Astrophysical Phenomena · Physics 2015-06-23 E. V. Kravchenko , W. D. Cotton , Y. Y. Kovalev
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