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In the WMAP era of high precision cosmology an accurate determination of the matter power spectrum from lyman-alpha forest data becomes crucial. When combining the matter power spectrum derived from CMB experiments with that inferred from…

Astrophysics · Physics 2007-05-23 Matteo Viel

We determine the $\mathcal{O}(\alpha)$ correction to the energy spectrum of electrons produced in the decay of muons bound in atoms. We focus on the high-energy end of the spectrum that constitutes a background for the muon-electron…

High Energy Physics - Phenomenology · Physics 2016-01-20 Robert Szafron , Andrzej Czarnecki

Last year I talked at this meeting about a possible time dependence of the QCD coupling constant $\alpha_s$. This year I shall look into the problem once more, without fully repeating the arguments given last year. Astrophysical indications…

High Energy Physics - Phenomenology · Physics 2009-11-10 Harald Fritzsch

We present an effective field theory (EFT) approach to extract fundamental cosmological parameters from the Lyman-alpha forest flux fluctuations as an alternative to the standard simulation-based techniques. As a first application, we…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-21 Mikhail M. Ivanov , Michael W. Toomey , Naim Göksel Karaçaylı

I review recent constraints on and claimed detections of a time-varying fine-structure constant $\alpha$, and discuss our own work, particularly on the effects of $\alpha$ in the cosmic microwave background and large-scale structure. Our…

Astrophysics · Physics 2007-05-23 C. J. A. P. Martins

We show that constraints from perturbative QCD calculations play a role in the nucleon to Delta(1232) electromagnetic transition even at moderate momentum transfer scales. The pQCD constraints, tied to real photoproduction data and…

High Energy Physics - Phenomenology · Physics 2009-10-31 Carl E. Carlson , Nimai C. Mukhopadhyay

Parity-violating elastic electron-nucleon scattering at low momentum transfer allows one to access the nucleon's weak charge, the vector coupling of the $Z$-boson to the nucleon. In the Standard Model and at tree level, the weak charge of…

Nuclear Theory · Physics 2016-11-23 Mikhail Gorchtein , Hubert Spiesberger

In this paper, we combine the latest observational data, including the WMAP five-year data (WMAP5), BOOMERanG, CBI, VSA, ACBAR, as well as the Baryon Acoustic Oscillations (BAO) and Type Ia Supernoave (SN) "Union" compilation (307 sample)…

Astrophysics · Physics 2008-11-26 Jun-Qing Xia , Hong Li , Gong-Bo Zhao , Xinmin Zhang

We present constraints on neutrino masses, the primordial fluctuation spectrum from inflation, and other parameters of the $\Lambda$CDM model, using the one-dimensional Ly$\alpha$-forest power spectrum measured by Palanque-Delabrouille et…

Many cosmological models invoke rolling scalar fields to account for the observed acceleration of the expansion of the universe. These theories generally include a potential V(phi) which is a function of the scalar field phi. Although…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Rodger I. Thompson , C. J. A. P. Martins , P. E. Vielzeuf

We estimate sensitivity coefficients to variation of the fine-structure constant alpha and electron-to-proton mass ratio mu for microwave Lambda-type transitions in CH molecule and for inversion-rotational transitions in partly deuterated…

Cosmology and Nongalactic Astrophysics · Physics 2009-10-27 M. G. Kozlov , A. V. Lapinov , S. A. Levshakov

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

We obtain constraints on the variation of the fundamental constants from the full shape of the redshift-space correlation function of a sample of luminous galaxies drawn from the Data Release 9 of the Baryonic Oscillations Spectroscopic…

Should muon-to-electron conversion in the field of a nucleus be found in the current generation of experiments, the measurement of the atomic number dependence of the process will become an important experimental goal. We present a new…

High Energy Physics - Phenomenology · Physics 2025-05-28 Léo Borrel , David G. Hitlin , Sophie Middleton

This article describes the various experimental bounds on the variation of the fundamental constants of nature. After a discussion on the role of fundamental constants, of their definition and link with metrology, the various constraints on…

High Energy Physics - Phenomenology · Physics 2008-11-26 Jean-Philippe Uzan

The large-scale maximum at k~0.05 identified in the power-spectrum of galaxy fluctuations provides a co-moving scale for measuring cosmological curvature. In shallow 3D surveys the peak is broad, but appears to be well resolved in 1D, at…

Astrophysics · Physics 2007-05-23 Tom Broadhurst , Andrew H. Jaffe

The data on atmospheric neutrinos can be explained assuming the existence of oscillations between muon neutrinos and light sterile neutrinos with mixing close to maximal, and Delta_m^2 approximately equal to 3 E-3 (eV^2). This…

High Energy Physics - Phenomenology · Physics 2017-09-06 Pasquale Di Bari , Paolo Lipari , Maurizio Lusignoli

We consider the possibility of the coupling constants of the $SU(3)\times SU(2)\times U(1)$ gauge interactions at the time of big bang nucleosynthesis having taken different values from what we measure at present, and investigate the…

High Energy Physics - Phenomenology · Physics 2009-11-07 Kazuhide Ichikawa , M. Kawasaki

This paper describes the search for a high-mass narrow-width scalar particle decaying into a Z boson and a photon. The analysis is performed using proton-proton collision data recorded with the CMS detector at the LHC at center-of-mass…

High Energy Physics - Experiment · Physics 2017-01-24 CMS Collaboration

We consider the inference of the cosmic radiation density, traditionally parameterised as the effective number of neutrino species N_eff, from precision cosmological data. Paying particular attention to systematic effects, notably…

Astrophysics · Physics 2008-11-26 Jan Hamann , Steen Hannestad , Georg G. Raffelt , Yvonne Y. Y. Wong
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