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Related papers: The UVES Large Program for testing fundamental phy…

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Astrophysical tests of the stability of fundamental couplings are becoming an increasingly important probe of new physics. Motivated by the recent availability of new and stronger constraints we update previous works testing the consistency…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-31 C. J. A. P. Martins , A. M. M. Pinho

We use weak lensing data from the Hubble Space Telescope COSMOS survey to measure the second- and third-moments of the cosmic shear field, estimated from about 450,000 galaxies with average redshift <z> ~ 1.3. We measure two- and…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Elisabetta Semboloni , Tim Schrabback , Ludovic van Waerbeke , Sanaz Vafaei , Jan Hartlap , Stefan Hilbert

Molecular transitions recently discovered at redshift z_abs=2.059 toward the bright background quasar J2123-0050 are analysed to limit cosmological variation in the proton-to-electron mass ratio, mu=m_p/m_e. Observed with the Keck…

We analyze the consistency of different astronomical data of the variation in the fine-structure constant obtained with KECK and VLT. We tested the consistency using the Student test and confidence intervals. We splited the data sets in to…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-27 Lucila Kraiselburd , Susana J. Landau , Claudio Simeone

Using the Cosmic Origins Spectrograph (COS) aboard the Hubble Space Telescope with both far-UV (FUV) and near-UV (NUV) gratings, we measure the ionizing spectra of two bright, intermediate-redshift quasars in their rest-frame extreme…

Astrophysics of Galaxies · Physics 2025-08-15 J. Michael Shull , Rongmon Bordoloi , Charles W. Danforth

High-fidelity spectroscopy presents challenges for both observations and in designing instruments. High-resolution and high-accuracy spectra are required for verifying hydrodynamic stellar atmospheres and for resolving intergalactic…

Instrumentation and Methods for Astrophysics · Physics 2015-05-18 Dainis Dravins

We find that the Fe III$\lambda\lambda$2039-2113 spectral feature in quasars appears systematically redshifted by amounts accountable under the hypothesis of gravitational redshift induced by the central supermassive black hole. Our…

Astrophysics of Galaxies · Physics 2018-08-08 E. Mediavilla , J. JimÉnez-Vicente , C. Fian , J. A. MuÑoz , E. Falco , V. Motta , E. Guerras

We present a detailed analysis of present and future Cosmic Microwave Background constraints of the value of the fine-structure constant, $\alpha$. We carry out a more detailed analysis of the WMAP first-year data, deriving state-of-the-art…

One of the topical problems of contemporary physics is a possible variability of the fundamental constants. Here we consider possible variability of two dimensionless constants which are most important for calculation of atomic and…

Atomic Physics · Physics 2016-09-08 D. A. Varshalovich , A. Y. Potekhin , A. V. Ivanchik

The detection of a spatial variation of the fine-structure constant, alpha, based on study of quasar absorption systems has recently been reported. The physics that causes this alpha-variation should have other observable manifestations,…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-16 J. C. Berengut , V. V. Flambaum , J. A. King , S. J. Curran , J. K. Webb

We present deep Keck/MOSFIRE near-infrared spectroscopy of a strong Lyman alpha emitting source at z=6.1292, HSC J142331.71-001809.1, which was discovered by the SHELLQS program from imaging data of the Subaru Hyper Suprime-Cam (HSC)…

In the second paper of this series we extend our Bayesian reanalysis of the evidence for a cosmic variation of the fine structure constant to the semi-parametric modelling regime. By adopting a mixture of Dirichlet processes prior for the…

Instrumentation and Methods for Astrophysics · Physics 2013-09-12 Ewan Cameron , Tony Pettitt

In a recent publication [Ferreira {\it et al.}, Phys. Rev. D89 (2014) 083011] we tested the consistency of current astrophysical tests of the stability of the fine-structure constant $\alpha$ and the proton-to-electron mass ratio…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 M. C. Ferreira , C. J. A. P. Martins

We probe the evolution of the fine-structure constant, alpha, with cosmic time. Accurate positions of the FeII lines 1608, 2382,and 2600 A are measured in the z = 1.84 absorption system from a high-resolution (FWHM = 3.8 km/s) and high…

We measure quasar variability using the Panoramic Survey Telescope and Rapid Response System 1 Survey (Pan-STARRS1 or PS1) and the Sloan Digital Sky Survey (SDSS) and establish a method of selecting quasars via their variability in 10,000…

We publicly release a new sample of $34$ medium resolution quasar spectra at $5.77\leq z_{\rm em}\leq6.54$ observed with the Echellette Spectrograph and Imager (ESI) on the Keck telescope. This quasar sample represents an ideal laboratory…

Astrophysics of Galaxies · Physics 2018-09-05 Anna-Christina Eilers , Frederick B. Davies , Joseph F. Hennawi

Recently, two classes of quasar samples were identified, which are promising as new cosmological probes extending to higher redshifts. The first sample uses the nonlinear relation between the ultraviolet and X-ray luminosities of quasars to…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-15 Xiaogang Zheng , Shuo Cao , Marek Biesiada , Xiaolei Li , Tonghua Liu , Yuting Liu

A sample of 14 pre-main sequence visual binary systems in southern star-forming regions were imaged at 2 um with the Keck I telescope to search for tertiary companions, scattered-light disks, and compact nebulae at linear scales of 5-100…

Astrophysics · Physics 2009-11-07 C. D. Koresko

We use Fisher Matrix analysis techniques to forecast the cosmological impact of astrophysical tests of the stability of the fine-structure constant to be carried out by the forthcoming ESPRESSO spectrograph at the VLT (due for commissioning…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-01 C. S. Alves , T. A. Silva , C. J. A. P. Martins , A. C. O. Leite

Endeavours of the unification of the four fundamental interactions have resulted in a development of theories having cosmological solutions in which low-energy limits of fundamental physical constants vary with time. The validity of such…

Astrophysics · Physics 2011-05-23 A. V. Ivanchik , A. Y. Potekhin , D. A. Varshalovich
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