Searcharxiv⌕ Search
Home/Archive/arXiv

arXiv · hep-ph/0603251

Constraint on Right-Handed Squark Mixings from B_s - B_sbar Mass Difference

Motoi Endo·Satoshi Mishima
View original source ↗Read source document ↗Export metadata ↓

Abstract

We point out that the right-handed squark mixings can sizably enhance SUSY contributions to Delta M_s by taking into account renormalization group effects via the CKM matrix. The recent result of Delta M_s from the D0 experiment at the Tevatron thus implies a strong constraint on the right-handed mixings.

Explore related subjects

hep-ph

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Motoi Endo, Satoshi Mishima. 2006-07-29. Constraint on Right-Handed Squark Mixings from B_s - B_sbar Mass Difference. https://doi.org/10.1016/j.physletb.2006.07.061

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Chiral perturbation theory with vector mesons and the pion electromagnetic form factor

We formulate chiral perturbation theory with vector mesons kept as explicit intermediate degrees of freedom, in the regime where the momentum carried by a vector meson is of order $Q$ while its mass is of order $Λ_χ$. This is the regime relevant to vector-meson exchange in nuclear forces and low-energy nuclear electroweak processes. We use the corresponding power counting and show that it gives a consistent one-loop expansion, with the divergences generated by the leading-order Lagrangian absorbed by next-to-leading-order counterterms. As an application, we calculate the pion electromagnetic form factor. The vector mesons introduce a single new leading-order parameter, $a$. For the KSRF value $a=2$, the nonlocal one-loop contribution to the direct photon--pion vertex vanishes at NLO, while the remaining local term is found to be consistent with zero when fixed from the pion charge radius and $ρ$-meson decay data. Vector-meson dominance therefore emerges as a good numerical approximation at this order. The explicit $ρ$ propagator, kept in its resummed form, also reproduces the observed curvature of the form factor more efficiently than vector-meson-less one-loop ChPT. We also present a phenomenological extension of the form factor into the $ρ$ resonance region, using a resummation of the $ρ$ self-energy. The relation to other formulations with explicit vector mesons is also discussed.

hep-ph↗
arXiv2026

New Supernova Constraints on Vector-Mediated Neutrinophilic Dark Sector

Supernova cooling has long been used to constrain physics beyond the Standard Model, typically involving new mediators or dark matter (DM) particles that couple to nucleons or electrons. In this work, we show that the large density of neutrinos inside the neutrinosphere of supernovae also makes them powerful laboratories to study nonstandard neutrino interactions with a {\it neutrinophilic} dark sector, i.e.~DM and mediator particles interacting primarily with neutrinos. In this case, we find that the existing constraints are rather weak, and for a wide range of currently unconstrained parameter space, neutrino annihilation within a supernova could copiously produce such neutrinophilic DM at a large enough rate to cause noticeable anomalous cooling. From the non-observation of such anomalous cooling in SN1987A, we thus set new constraints on neutrino-DM interactions, which provide up to five orders of magnitude improvement in the effective coupling over the existing constraints for DM masses below ${\cal O}$(100 MeV).

hep-ph↗
arXiv2026

First simultaneous analysis of transverse momentum dependent and collinear parton distributions in the proton

We present the first simultaneous global QCD analysis of unpolarized transverse momentum dependent (TMD) and collinear parton distribution functions (PDFs) in the proton. Our study incorporates data from deep-inelastic scattering, Drell-Yan, inclusive weak boson, $W$+\,charm, and jet production involving PDFs, as well as TMD Drell-Yan and $Z$-boson production data from fixed target and collider experiments sensitive to both TMD and collinear distributions. The analysis is performed at next-to-next-to-leading logarithmic accuracy for QCD resummation in TMD observables and next-to-leading order for observables described in collinear factorization. The combined analysis improves knowledge of both TMD and collinear PDFs, particularly in the sea-quark sector, providing a consistent simultaneous description of the aforementioned observables.

hep-ph↗