scholarly journals Atomic Transition Frequencies, Isotope Shifts, and Sensitivity to Variation of the Fine Structure Constant for Studies of Quasar Absorption Spectra

2011 ◽  
pp. 9-16 ◽  
Author(s):  
J. C. Berengut ◽  
V. A. Dzuba ◽  
V. V. Flambaum ◽  
J. A. King ◽  
M. G. Kozlov ◽  
...  
Keyword(s):  
Fine Structure ◽  
Absorption Spectra ◽  
Structure Constant ◽  
Atomic Transition ◽  
Fine Structure Constant ◽  
Isotope Shifts

scholarly journals An Updated Constraint on Variations of the Fine-Structure Constant Using Wavelengths of Fe II Absorption Line Multiplets

Symmetry ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 722 ◽  
Author(s):  
T. D. Le
Keyword(s):  
Fine Structure ◽  
Absorption Line ◽  
Absorption Spectra ◽  
Structure Constant ◽  
Fine Structure Constant ◽  
The Future ◽  
Stringent Limit

A new stringent limit relating to the variation of the fine-structure constant (α= e2/4πε0ℏc) has been extracted from Ritz wavelengths of 27 quasi_stellar object (QSO) absorption spectra lines of Fe II. The calculation was combined with laboratory wavelengths and QSO spectra to obtain the result ∆α/α=(0.027±0.832)×10-6. This result suggests how dedicated astrophysical estimations can improve these limits in the future and can also constrain space_time variations.

scholarly journals Search for variation of the fundamental constants in atomic, molecular, and nuclear spectra

2009 ◽  
Vol 87 (1) ◽  
pp. 25-33 ◽  
Author(s):  
V V Flambaum ◽  
V A Dzuba
Keyword(s):  
Fine Structure ◽  
Absorption Spectra ◽  
Atomic Clock ◽  
Structure Constant ◽  
Fine Structure Constant ◽  
Frequency Change ◽  
Fundamental Constants ◽  
Mass Ratio ◽  
Proton Mass ◽  
Nuclear Transitions

The search for variation of the fundamental constants such as the fine-structure constant α (α = e2/hc) and the ratios of fundamental masses (for example, electron-to-proton mass ratio μ = me/mp) is reviewed. Strong emphasis is given to establishing the relationships between the change in the measured frequencies of atomic, molecular, or nuclear transitions and the corresponding change of the fundamental constants. Transitions in which the sensitivity of the frequency change to the variation of the fine-structure constant is strongly enhanced are discussed and most recent experimental results are presented. Most attention is given to the use of atomic, molecular, and nuclear transitions in the study of quasar absorption spectra and in atomic clock experiments.PACS Nos.: 31.25.Eb, 31.25.Jf

scholarly journals Atomic calculations and search for variation of the fine-structure constant in quasar absorption spectra

2009 ◽  
Vol 87 (1) ◽  
pp. 15-23 ◽  
Author(s):  
V A Dzuba ◽  
V V Flambaum
Keyword(s):  
Fine Structure ◽  
Absorption Spectra ◽  
Periodic Table ◽  
Structure Constant ◽  
Electron Structure ◽  
Special Consideration ◽  
Fine Structure Constant ◽  
Critical Compilation

A brief review of the search for variation of the fine-structure constant in quasar absorption spectra is presented. Special consideration is given to the role of atomic calculations in the analysis of the observed data. A range of methods that allows us to perform calculations for atoms or ions with different electron structure and which cover practically all the Periodic Table of elements is discussed. Critical compilation of the results of the calculations as well as a review of the most recent results of the analysis are presented.PACS Nos.: 31.25.Eb, 31.25.Jf

scholarly journals New Limit on Space-Time Variations in the Proton-to-Electron Mass Ratio from Analysis of Quasar J110325-264515 Spectra

Symmetry ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 344
Author(s):  
T. D. Le
Keyword(s):  
Fine Structure ◽  
Structure Constant ◽  
Space Time ◽  
Fine Structure Constant ◽  
Electron Mass ◽  
Mass Ratio ◽  
Quasar Spectra ◽  
Time Variations ◽  
Using Data ◽  
The Universe

Astrophysical tests of current values for dimensionless constants known on Earth, such as the fine-structure constant, α , and proton-to-electron mass ratio, μ = m p / m e , are communicated using data from high-resolution quasar spectra in different regions or epochs of the universe. The symmetry wavelengths of [Fe II] lines from redshifted quasar spectra of J110325-264515 and their corresponding values in the laboratory were combined to find a new limit on space-time variations in the proton-to-electron mass ratio, ∆ μ / μ = ( 0.096 ± 0.182 ) × 10 − 7 . The results show how the indicated astrophysical observations can further improve the accuracy and space-time variations of physics constants.

scholarly journals Measurement of the running of the fine structure constant below 1 GeV with the KLOE detector

2019 ◽  
Vol 218 ◽  
pp. 02012
Author(s):  
Graziano Venanzoni
Keyword(s):  
Fine Structure ◽  
Energy Region ◽  
Direct Evidence ◽  
Branching Ratio ◽  
Structure Constant ◽  
Fine Structure Constant ◽  
Recent Measurement ◽  
Single Measurement ◽  
Lepton Universality ◽  
Hadronic Contribution

I will report on the recent measurement of the fine structure constant below 1 GeV with the KLOE detector. It represents the first measurement of the running of α(s) in this energy region. Our results show a more than 5σ significance of the hadronic contribution to the running of α(s), which is the strongest direct evidence both in time-and space-like regions achieved in a single measurement. From a fit of the real part of Δα(s) and assuming the lepton universality the branching ratio BR(ω → µ+µ−) = (6.6 ± 1.4stat ± 1.7syst) · 10−5 has been determined

scholarly journals Fine structure constant and the CMB damping scale

2012 ◽  
Vol 85 (10) ◽  
Author(s):  
Eloisa Menegoni ◽  
Maria Archidiacono ◽  
Erminia Calabrese ◽  
Silvia Galli ◽  
C. J. A. P. Martins ◽  
...  
Keyword(s):  
Fine Structure ◽  
Structure Constant ◽  
Fine Structure Constant
Sign in / Sign up

Export Citation Format

Share Document