English
Related papers

Related papers: Constraints on the spacetime variation of the fine…

200 papers

We present constraints on the spacetime variation of the fine-structure constant $\alpha$ at redshifts $2.5\le z<9.5$ using JWST emission-line galaxies. The galaxy sample consists of 621 high-quality spectra with strong and narrow [O III]…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-22 Linhua Jiang , Shuqi Fu , Feige Wang , Sarah E. I. Bosman , Zheng Cai , Hyunsung D. Jun , Zhiwei Pan , Fengwu Sun , Jinyi Yang , Huanian Zhang

From the Sloan Digital Sky Survey (SDSS) Data Release 12, which covers the full Baryonic Oscillation Spectroscopic Survey (BOSS) footprint, we investigate the possible variation of the fine-structure constant over cosmological time-scales.…

The [O III] $\lambda\lambda\ 4960,5008$ emission lines in the optical spectra of galaxies and quasars have been widely used to investigate the possible variation of the fine-structure constant $\alpha$ over cosmic time. In this work, we…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-08 Jin-Nan Wei , Rui-Jie Chen , Jun-Jie Wei , Martín López-Corredoira , Xue-Feng Wu

[O III]$\lambda\lambda$4960,5008 doublet are often the strongest narrow emission lines in starburst galaxies and quasi-stellar objects (QSOs), and thus are a promising probe to possible variation of the fine-structure constant $\alpha$ over…

Astrophysics of Galaxies · Physics 2023-10-30 Ge Li , Luming Sun , Xiangjun Chen , Hongyan Zhou

We report a robust constrain on the possible variation of fine-structure constant, alpha = e^2/(hbar*c), obtained using O III 4959,5007, nebular emission lines from QSOs. We find Delta-alpha/alpha=-(2.1 +/- 1.6) x 10^(-5) based on a well…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 H. Rahmani , N. Maheshwari , R. Srianand

We report a new constraint on the variation of the fine-structure constant based on the analysis of 15 Si IV doublets selected from a ESO-UVES sample. We find \Delta\alpha/\alpha = (+0.15+/-0.43) x 10^-5 over a redshift range of 1.59< z <…

Astrophysics · Physics 2009-11-10 Hum Chand , Patrick Petitjean , Raghunathan Srianand , Bastien Aracil

The Dark Energy Spectroscopic Instrument (DESI) will precisely constrain cosmic expansion and the growth of structure by collecting $\sim$40 million extra-galactic redshifts across $\sim$80\% of cosmic history and one third of the sky. The…

A method offering an order of magnitude sensitivity gain is described for using quasar spectra to investigate possible time or space variation in the fine structure constant, alpha. Applying the technique to a sample of 30 absorption…

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…

Star-forming galaxies at high redshifts are the ideal targets to probe the hypothetical variation of the fine-structure constant alpha over cosmological time scales. We propose a modification of the alkali doublets method which allows us to…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-10 S. A. Levshakov , M. G. Kozlov

The offsets between the radial velocities of the rotational transitions of carbon monoxide and the fine structure transitions of neutral and singly ionized carbon are used to test the hypothetical variation of the fine structure constant,…

Astrophysics of Galaxies · Physics 2017-08-23 S. A. Levshakov , K. -W. Ng , C. Henkel , B. Mookerjea

It was hypothesized in the literature that some physical parameters may be time-evolving and the astrophysical data can serve as a probe. Recently, James Webb Space Telescope (JWST) have released its early observations. In this work, we…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-15 Ze-Fan Wang , Lei Lei , Lei Feng , Yi-Zhong Fan

The optical spectra of objects classified as QSOs in the SDSS DR6 are analyzed with the aim of determining the value of the fine structure constant in the past and then check for possible changes in the constant over cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 C. M. Gutierrez , M. Lopez-Corredoira

We investigate the variation of the fine-structure constant, {\alpha}, in symmetron models using N-body simulations in which the full spatial distribution of {\alpha} at different redshifts has been calculated. In particular, we obtain…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-29 Marvin F. Silva , Hans A. Winther , David F. Mota , C. J. A. P. Martins

The Dark Energy Spectroscopic Instrument (DESI) is a massively multiplexed fiber-fed spectrograph that will make the next major advance in dark energy in the timeframe 2018-2022. On the Mayall telescope, DESI will obtain spectra and…

Spectroscopic surveys such as the Dark Energy Spectroscopic Instrument (DESI) and Euclid are mapping the spatial distribution of millions of galaxies, with Emission Line Galaxies (ELGs) serving as the dominant tracer in the redshift range…

As an extension of the method by Bahcall et al. (2004) to investigate the time dependence of the fine structure constant, we describe an approach based on new observations of forbidden line multiplets from different ionic species. We obtain…

Astrophysics · Physics 2008-11-26 Dirk Grupe , Anil K. Pradhan , Stephan Frank

The large scale structure catalogs within DESI Data Release 1 (DR1) use nearly 6 million galaxies and quasars as tracers of the large-scale structure of the universe to measure the expansion history with baryon acoustic oscillations and the…

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
‹ Prev 1 2 3 10 Next ›