Physics – High Energy Physics – High Energy Physics - Phenomenology
Scientific paper
1997-08-07
Phys.Rev. D56 (1997) 8074-8081
Physics
High Energy Physics
High Energy Physics - Phenomenology
21pp RevTeX, 1 eps fig, uses graphics style, typo corrected, and corrected file sent this time. To appear in Physical Review D
Scientific paper
10.1103/PhysRevD.56.8074
A particular class of variant axion models with two higgs doublets and a singlet is studied. In these models the axion couples either to the $u$-quark or $t$-quark or both, but not to $b$, $c$, $s$, or $d$. When the axion couples to only one quark the models possess the desirable feature of having no domain wall problem, which makes them viable candidates for a cosmological axion string scenario. We calculate the axion couplings to leptons, photons and nucleons, and the astrophysical constraints on the axion decay constant $v_a$ are investigated and compared to the DFSZ axion model. We find that the most restrictive lower bound on $v_a$, that from SN1987a, is lowered by up to a factor of about 30, depending on the model and also the ratio of the vacuum expectation values of the higgs doublets. For scenarios with axionic strings, the allowed window for $v_a$ in the $u$ quark model can be more than two orders of magnitude. For inflationary scenarios, the cosmological upper bound on $v_a/N$, where $N$ is the QCD anomaly factor, is unaffected: however, the variant models have $N$ either 3 or 6 times smaller than the DFSZ model.
Hindmarsh Mark
Moulatsiotis Photis
No associations
LandOfFree
Constraints on Variant Axion Models 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 Constraints on Variant Axion Models, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Constraints on Variant Axion Models will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-452270