Searching for chameleon-like scalar fields with the ammonia method

Details Searching for chameleon-like scalar fields with the ammonia method Searching for chameleon-like scalar fields with the ammonia method

2009-11-19

arxiv.org/abs/0911.3732v2

Astronomy and Astrophysics

Astrophysics

Cosmology and Extragalactic Astrophysics

23 pages, 11 figures, 6 tables. Accepted for publication in A&A. Title and text corrected, references updated

Scientific paper

(Abridged) The ammonia method, which has been proposed to explore the electron-to-proton mass ratio, mu = m_e/m_p, is applied to nearby dark clouds in the Milky Way. This ratio, which is measured in different physical environments of high (terrestrial) and low (interstellar) densities of baryonic matter is supposed to vary in chameleon-like scalar field models, which predict strong dependence of both masses and coupling constant on the local matter density. High resolution spectral observations of molecular cores in lines of NH3 (J,K) = (1,1), HC3N J = 2-1, and N2H+ J = 1-0 were performed at three radio telescopes to measure the radial velocity offsets, DeltaV = V_rot - V_inv, between the inversion transition of NH3 (1,1) and the rotational transitions of other molecules with different sensitivities to the parameter dmm = (mu_obs - mu_lab)/mu_lab. The measured values of DeltaV exhibit a statistically significant velocity offset of 23 +/- 4_stat +/- 3_sys m/s. When interpreted in terms of the electron-to-proton mass ratio variation, this infers that dmm = (2.2 +/- 0.4_stat +/- 0.3_sys)x10^{-8}. If only a conservative upper bound is considered, then the maximum offset between ammonia and the other molecules is |DeltaV| <= 30 m/s. This gives the most accurate reference point at z = 0 for dmm: |dmm| <= 3x10^{-8}.

Affiliated with

Also associated with

No associations

Rating

Searching for chameleon-like scalar fields with the ammonia method 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 Searching for chameleon-like scalar fields with the ammonia method, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Searching for chameleon-like scalar fields with the ammonia method will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-452708