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This paper presents the constraints on the time variation of the fine structure constant at recombination relative to its present value, Delta_alpha = (alpha_rec-alpha_0) / alpha_0, obtained from the analysis of the WMAP-3yr Cosmic…

Astrophysics · Physics 2008-11-26 Petruta Stefanescu

We have measured the diameters of the Cepheid variables delta Cephei (18 nights) and eta Aquilae (11 nights) with the Navy Prototype Optical Interferometer. The primary results of these observations are the mean angular diameters…

We present a detailed analysis of redshift-space distortions in the two-point correlation function of the 6dF Galaxy Survey (6dFGS). The K-band selected sub-sample which we employ in this study contains 81971 galaxies distributed over…

A new method based on large-scale structure observations is proposed to probe a possible time variation of the fine-structure constant ($\alpha$). Our analyses are based on time-delay of Strong Gravitational Lensing and Type Ia Supernovae…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-09 L. R. Colaço , J. E. Gonzalez , R. F. L. Holanda

We present a novel technique to measure $\sigma_8$, by measuring the dependence of the second-order bias of a density field on $\sigma_8$ using two separate techniques. Each technique employs area-averaged angular correlation functions…

Astrophysics · Physics 2011-04-20 Ashley J. Ross , Robert J. Brunner , Adam D. Myers

We detail a powerful indirect method for the study of damped Lyman alpha systems (DLAs) at low redshift. We increase the probability of finding a low-redshift DLA to nearly 50% by targeting QSOs that are known to have strong low-redshift…

Astrophysics · Physics 2016-01-27 Daniel B. Nestor , Sandhya Rao , David Turnshek

The metal-poor damped Lyman alpha (DLA) system at z = 3.04984 in the QSO SDSSJ1419+0829 has near-ideal properties for an accurate determination of the primordial abundance of deuterium, (D/H)_p. We have analysed a high-quality spectrum of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Max Pettini , Ryan Cooke

Aims. We constrain a hypothetical variation in the fundamental physical constants over the course of cosmic time. Methods. We use unique observations of the CO(7-6) rotational line and the [CI] 3P_2 - 3P_1 fine-structure line towards a…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-12 S. A. Levshakov , F. Combes , F. Boone , I. I. Agafonova , D. Reimers , M. G. Kozlov

Most of the successful physical theories rely on the constancy of few fundamental quantities (such as the speed of light, $c$, the fine-structure constant, \alpha, the proton to electron mass ratio, \mu, etc), and constraining the possible…

Astrophysics · Physics 2008-11-26 Raghunathan Srianand , Hum Chand , Patrick Petitjean , Bastien Aracil

Recent papers have shown that a small systematic redshift shift ($\Delta z\sim 10^{-5}$) in measurements of type Ia supernovae can cause a significant bias ($\sim$1\%) in the recovery of cosmological parameters. Such a redshift shift could…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-25 Josh Calcino , Tamara Davis

The muon decay parameter delta characterizes momentum dependence of the parity-violating muon decay asymmetry. A new measurement of delta has been performed using the first physics data recorded by the TWIST experiment at TRIUMF. The…

High Energy Physics - Experiment · Physics 2011-04-18 Andrei Gaponenko

Strong evidence has recently emerged for a variation in the fine structure constant, $\alpha\equiv e^2/\hbar c$, over the history of the Universe. This was concluded from a detailed study of the relative positions of redshifted optical…

Astrophysics · Physics 2009-11-10 S. J. Curran , N. Kanekar , J. K. Darling

We present a new algorithm having a time complexity of O(N log N) and designed to retrieve the phase at which an input signal and a set of not necessarily orthogonal templates match best in a weighted chi-squared sense. The proposed…

Instrumentation and Methods for Astrophysics · Physics 2017-09-28 L. Delchambre

We use high resolution Eulerian hydrodynamics simulations to study kinematic properties of the low ionization species in damped Ly-alpha systems at redshift z=3. Our adaptive mesh refinement simulations include most key ingredients relevant…

Astrophysics · Physics 2009-11-13 Alexei O. Razoumov , Michael L. Norman , Jason X. Prochaska , Arthur M. Wolfe

We propose a method to determine the cosmic mass density Omega from redshift-space distortions induced by large-scale flows in the presence of nonlinear clustering. Nonlinear structures in redshift space such as fingers of God can…

Astrophysics · Physics 2009-10-30 B. C. Bromley , M. S. Warren , W. H. Zurek

In this paper, new bounds on possible variations of the fine structure constant, $\alpha$, for a class of runaway dilaton models are performed. By considering a possible evolution with redshift, $z$, such as…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-01 R. F. L. Holanda , L. R. Colaço , R. S. Gonçalves , J. S. Alcaniz

We present the first experimental study of the carrier density dependence of the composite fermion conductivity $\sigma^{CF}_{xx}$ at Landau level filling factors $\nu= {1/2}$ and $\nu= {3/2}$ in high-quality front-gated…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 C. -T. Liang , M. Y. Simmons , D. A. Ritchie , M. Pepper

We image 19 quasars with 22 damped Lyman alpha (DLA) systems using the F160W filter and the Near-Infrared Camera and Multiobject Spectrograph aboard the Hubble Space Telescope, in both direct and coronagraphic modes. We reach 5 sigma…

Astrophysics · Physics 2009-11-07 James W. Colbert , Matthew A. Malkan

Testing the spatial variation of fine-structure constant $\alpha$ indicated in [Webb et al., Phys. Rev. Lett. 107, 191101 (2011)] with terrestrial laboratory atomic measurements requires at least $\dot{\alpha}/\alpha \sim…

Atomic Physics · Physics 2016-01-20 V. A. Dzuba , M. S. Safronova , U. I. Safronova , V. V. Flambaum

A measurement of Bs J/psi phi decay parameters, including the CP-violating weak phase phi_s and the decay width difference Delta Gamma_s is reported, using 4.9 fb-1 of integrated luminosity collected in 2011 by the ATLAS detector from LHC…

High Energy Physics - Experiment · Physics 2013-06-11 ATLAS Collaboration
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