Constraining Variations in the Fine-structure Constant, Quark Masses and the Strong Interaction

Details Constraining Variations in the Fine-structure Constant, Quark Masses and the Strong Interaction Constraining Variations in the Fine-structure Constant, Quark Masses and the Strong Interaction

2003-10-11

arxiv.org/abs/astro-ph/0310318v3

Lect.Notes Phys.648:131-150,2004

Astronomy and Astrophysics

Astrophysics

20 pages, 6 Figures (9 EPS files), 1 Table, to appear in Lecture Notes in Physics, Proc. 302 WE Heraeus Seminar: Astrophysics,

Scientific paper

We present evidence for variations in the fine-structure constant from Keck/HIRES spectra of 143 quasar absorption systems over the redshift range 0.2 < z_abs < 4.2. This includes 15 new systems, mostly at high-z (z_abs > 1.8). Our most robust estimate is a weighted mean da/a=(-0.57 +/- 0.11)x10^{-5}. We respond to recent criticisms of the many-multiplet method used to extract these constraints. The most important potential systematic error at low-z is the possibility of very different Mg heavy isotope abundances in the absorption clouds and laboratory: {\it higher} abundances of {25,26}Mg in the absorbers may explain the low-z results. Approximately equal mixes of {24}Mg and {25,26}Mg are required. Observations of Galactic stars generally show {\it lower} {25,26}Mg isotope fractions at the low metallicities typifying the absorbers. Higher values can be achieved with an enhanced population of intermediate mass stars at high redshift, a possibility at odds with observed absorption system element abundances. At present, all observational evidence is consistent with the varying-alpha results. Another promising method to search for variation of fundamental constants involves comparing different atomic clocks. Here we calculate the dependence of nuclear magnetic moments on quark masses and obtain limits on the variation of alpha and m_q/Lambda_QCD from recent atomic clock experiments with hyperfine transitions in H, Rb, Cs, Hg+ and an optical transition in Hg+.

Affiliated with

Also associated with

No associations

Rating

Constraining Variations in the Fine-structure Constant, Quark Masses and the Strong Interaction does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Constraining Variations in the Fine-structure Constant, Quark Masses and the Strong Interaction, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Constraining Variations in the Fine-structure Constant, Quark Masses and the Strong Interaction will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-543213