Constraining the Variation in Fine-Structure Constant Using SDSS DR8 QSO
Spectra
H. Rahmani, N. Maheshwari, and R. Srianand. (2013)cite arxiv:1312.5324Comment: 5 pages, 3 figures; Accepted for publication in MNRAS Letter.
Abstract
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 selected sample of 2347 QSOs from Sloan Digital Sky Survey Data
Release 8 with 0.02 < z < 0.74. Our result is consistent with a non-varying
alpha at a level of 2 x 10^(-5) over approximately 7 Gyr. This is the largest
sample of extragalactic objects yet used to constrain the variation of alpha.
While this constraint is not as stringent as those determined using
many-multiplet method it is free from various systematic effects. A factor of ~
4 improvement in Delta-alpha/alpha achieved here compared to the previous study
(Bahcall et al. 2004) is just consistent with what is expected based on a
factor of 14 times bigger sample used here. This suggests that errors are
mainly dominated by the statistical uncertainty. We also find the ratio of
transition probabilities corresponding to the O III 5007 A and 4959 A lines to
be 2.933+/-0.002, in good agreement with the National Institute of Standards
and Technology measurements.
Description
[1312.5324] Constraining the Variation in Fine-Structure Constant Using SDSS DR8 QSO Spectra
%0 Generic
%1 rahmani2013constraining
%A Rahmani, H.
%A Maheshwari, N.
%A Srianand, R.
%D 2013
%K constant sdss structure variation
%T Constraining the Variation in Fine-Structure Constant Using SDSS DR8 QSO
Spectra
%U http://arxiv.org/abs/1312.5324
%X 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 selected sample of 2347 QSOs from Sloan Digital Sky Survey Data
Release 8 with 0.02 < z < 0.74. Our result is consistent with a non-varying
alpha at a level of 2 x 10^(-5) over approximately 7 Gyr. This is the largest
sample of extragalactic objects yet used to constrain the variation of alpha.
While this constraint is not as stringent as those determined using
many-multiplet method it is free from various systematic effects. A factor of ~
4 improvement in Delta-alpha/alpha achieved here compared to the previous study
(Bahcall et al. 2004) is just consistent with what is expected based on a
factor of 14 times bigger sample used here. This suggests that errors are
mainly dominated by the statistical uncertainty. We also find the ratio of
transition probabilities corresponding to the O III 5007 A and 4959 A lines to
be 2.933+/-0.002, in good agreement with the National Institute of Standards
and Technology measurements.
@misc{rahmani2013constraining,
abstract = {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 selected sample of 2347 QSOs from Sloan Digital Sky Survey Data
Release 8 with 0.02 < z < 0.74. Our result is consistent with a non-varying
alpha at a level of 2 x 10^(-5) over approximately 7 Gyr. This is the largest
sample of extragalactic objects yet used to constrain the variation of alpha.
While this constraint is not as stringent as those determined using
many-multiplet method it is free from various systematic effects. A factor of ~
4 improvement in Delta-alpha/alpha achieved here compared to the previous study
(Bahcall et al. 2004) is just consistent with what is expected based on a
factor of 14 times bigger sample used here. This suggests that errors are
mainly dominated by the statistical uncertainty. We also find the ratio of
transition probabilities corresponding to the O III 5007 A and 4959 A lines to
be 2.933+/-0.002, in good agreement with the National Institute of Standards
and Technology measurements.},
added-at = {2013-12-20T15:54:06.000+0100},
author = {Rahmani, H. and Maheshwari, N. and Srianand, R.},
biburl = {https://www.bibsonomy.org/bibtex/288fd9ff7fd0daf820b35b967f9b04b1b/miki},
description = {[1312.5324] Constraining the Variation in Fine-Structure Constant Using SDSS DR8 QSO Spectra},
interhash = {331a2c5a6f9983c6fbd133ce4d8200c5},
intrahash = {88fd9ff7fd0daf820b35b967f9b04b1b},
keywords = {constant sdss structure variation},
note = {cite arxiv:1312.5324Comment: 5 pages, 3 figures; Accepted for publication in MNRAS Letter},
timestamp = {2013-12-20T15:54:06.000+0100},
title = {Constraining the Variation in Fine-Structure Constant Using SDSS DR8 QSO
Spectra},
url = {http://arxiv.org/abs/1312.5324},
year = 2013
}