Search arXivSearch

arXiv · 1105.2818

Phenomenological consequences of radiative flavor violation in the MSSM

Abstract

In this article we investigate the consequences of radiative flavor violation (RFV) in the Minimal Supersymmetric Standard Model (MSSM). In this framework the small off-diagonal elements of the Cabibbo-Kobayashi-Maskawa (CKM) matrix and the small quark masses of the first two generations are generated from the trilinear supersymmetry-breaking terms. The impact of RFV on flavor-physics observables is studied in detail. We focus on the limiting cases in which the CKM matrix is either generated in the down-sector, i.e. by the soft SUSY-breaking mass insertions delta^dLR_i3 (i=1,2), or in the up-quark sector, i.e. by the mass insertions delta^uLR_i3. In the first case we find an enhancement of b->s gamma, which constrains the allowed range of sparticle masses (Fig. 3). In addition, neutral Higgs penguins significantly contribute to B_s,d->mu^+mu^- and, if also delta^dLR_32 is different from zero, these Higgs effects are capable of explaining the observed CP phase in the B_s system. If, on the other hand, the CKM generation takes place in the up-sector, |epsilon_K| receives additional positive contributions enforcing large squark and gluino masses (see Fig. 8). In this case also the rare decay K->pi nu nu receives sizable contributions. In conclusion we find that for SUSY masses around 1 TeV RFV is an interesting alternative to Minimal Flavor Violation (MFV).

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Andreas Crivellin, Lars Hofer, Ulrich Nierste, Dominik Scherer. 2011-12-06. Phenomenological consequences of radiative flavor violation in the MSSM. https://doi.org/10.1103/physrevd.84.035030

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

KEEP EXPLORING

Related papers

Stochastic Ultralight Dark Matter Fluctuations in Pulsar Timing Arrays

Metric perturbations induced by ultralight dark matter (ULDM) fields have long been identified as a potential target for pulsar timing array (PTA) observations. Previous works have focused on the coherent oscillation of metric perturbations at the characteristic frequency set by the ULDM mass. In this work, we show that ULDM fields source low-frequency stochastic metric fluctuations and that these low-frequency fluctuations can produce distinctive detectable signals in PTA data. Using the NANOGrav 12.5-year data set and synthetic data sets mimicking present and future PTA capabilities, we show that the current and future PTA observations provide the strongest probe of ULDM density within the solar system for masses in the range of $10^{-18}\;{\rm eV}-10^{-16}\;{\rm eV}$.

hep-ph

On the Origin of QCD Collectivity in High-Multiplicity Jets: A Transport Model Study

The CMS Collaboration has observed an enhancement of elliptic azimuthal anisotropy ($v^{\ast}_2$) in high-multiplicity jets. To investigate its microscopic origin, we employ a hybrid transport model that couples jets generated with \textsc{PYTHIA~8} to partonic and hadronic rescattering. The analysis is performed in the jet frame, where the jet momentum defines the longitudinal axis. We characterize the initial-state geometry using the eccentricity vectors of shower partons and quantify the geometric response by correlating them with the final-state flow vectors of hadrons. By systematically varying the partonic and hadronic interactions, we find that the anisotropy enhancement is dominated by hadronic rescattering in the present model and increases with the initial eccentricity. We further classify jets using the Soft Drop variable $z_gθ_g^β$ and show that this momentum-space substructure variable is sensitive to the initial coordinate-space geometry, although the predicted substructure dependence differs from the current CMS measurement. These results support a geometry--response mechanism for collective behavior inside jets and establish jet substructure as a promising experimental handle on the initial geometry. They also motivate models that treat parton branching and transport interactions concurrently.

hep-ph

Comprehensive effective field theory framework for coherent elastic neutrino-nucleus scattering

Coherent elastic neutrino-nucleus scattering (CE$ν$NS) stands out as a pivotal process for precision tests of the Standard Model electroweak sector, investigations of neutrino properties, and searches for new physics. Recent experimental measurements by COHERENT, CONUS+, and ton-scale xenon detectors--including PandaX-4T and XENONnT--underscore the need for a systematic theoretical framework to bridge high-energy physics scenarios with low-energy observational data. In this work, we develop a comprehensive end-to-end effective field theory (EFT) framework for CE$ν$NS, encompassing the complete energy scale hierarchy spanning the ultraviolet regime down to the nuclear sector. We consider the low-energy EFT (LEFT) operators up to dimension 8, incorporating their QCD renormalization group running effects, and employ the systematic spurion method to achieve matching between these operators and the chiral Lagrangian. A full power counting analysis is performed, extending to nuclear response functions, which evaluates contributions from LEFT operators up to dimension 8 while accounting for the nucleon number enhancement effect intrinsic to CE$ν$NS. Moreover, we match the relevant LEFT operators for CE$ν$NS onto operators up to dimension 8 within the Standard Model EFT. By also providing their complete tree-level ultraviolet completions, this procedure establishes a consistent top-down theoretical workflow. Leveraging a broad suite of CE$ν$NS experimental data, this framework enables a combined analysis to extract constraints on the scales of EFT operators and neutrino non-standard interaction parameters.

hep-ph