11 research outputs found
Belle II Executive Summary
Belle II is a Super Factory experiment, expected to record 50 ab
of collisions at the SuperKEKB accelerator over the next decade. The
large samples of mesons, charm hadrons, and tau leptons produced in the
clean experimental environment of collisions will provide the basis of
a broad and unique flavor-physics program. Belle II will pursue physics beyond
the Standard Model in many ways, for example: improving the precision of weak
interaction parameters, particularly Cabibbo-Kobayashi-Maskawa (CKM) matrix
elements and phases, and thus more rigorously test the CKM paradigm, measuring
lepton-flavor-violating parameters, and performing unique searches for
missing-mass dark matter events. Many key measurements will be made with
world-leading precision.Comment: 7 pages, to be submitted to the "Rare and Precision Measurements
Frontier" of the APS DPF Community Planning Exercise Snowmass 202
Mobile Acceptance and Commitment Therapy With Distressed First-Generation College Students: Microrandomized Trial
BackgroundExtant gaps in mental health services are intensified among first-generation college students. Improving access to empirically based interventions is critical, and mobile health (mHealth) interventions are growing in support. Acceptance and commitment therapy (ACT) is an empirically supported intervention that has been applied to college students, via mobile app, and in brief intervals.
ObjectiveThis study evaluated the safety, feasibility, and effectiveness of an ACT-based mHealth intervention using a microrandomized trial (MRT) design.
MethodsParticipants (N=34) were 18- to 19-year-old first-generation college students reporting distress, who participated in a 6-week intervention period of twice-daily assessments and randomization to intervention. Participants logged symptoms, moods, and behaviors on the mobile app Lorevimo. After the assessment, participants were randomized to an ACT-based intervention or no intervention. Analyses examined proximal change after randomization using a weighted and centered least squares approach. Outcomes included values-based and avoidance behavior, as well as depressive symptoms and perceived stress.
ResultsThe findings indicated the intervention was safe and feasible. The intervention increased values-based behavior but did not decrease avoidance behavior. The intervention reduced depressive symptoms but not perceived stress.
ConclusionsAn MRT of an mHealth ACT-based intervention among distressed first-generation college students suggests that a larger MRT is warranted. Future investigations may tailor interventions to contexts where intervention is most impactful.
Trial RegistrationClinicalTrials.gov NCT04081662; https://clinicaltrials.gov/show/NCT04081662
International Registered Report Identifier (IRRID)RR2-10.2196/1708
Snowmass 2021 White Paper on Upgrading SuperKEKB with a Polarized Electron Beam: Discovery Potential and Proposed Implementation
Upgrading the SuperKEKB electron-positron collider with polarized electron
beams opens a new program of precision physics at a center-of-mass energy of
10.58 GeV. This white paper describes the physics potential of this `Chiral
Belle' program. It includes projections for precision measurements of
that can be obtained from independent left-right asymmetry
measurements of transitions to pairs of electrons, muons, taus, charm
and b-quarks. The precision obtainable at SuperKEKB will match
that of the LEP/SLC world average, but at the centre-of-mass energy of 10.58
GeV. Measurements of the couplings for muons, charm, and -quarks will be
substantially improved and the existing discrepancy between the SLC
and LEP measurements will be addressed. Precision
measurements of neutral current universality will be more than an order of
magnitude more precise than currently available. As the energy scale is well
away from the -pole, the precision measurements will have sensitivity to
the presence of a parity-violating dark sector gauge boson, . The
program also enables the measurement of the anomalous magnetic moment
form factor of the to be made at an unprecedented level of precision. A
precision of level is accessible with 40~ab and with more data
it would start to approach the level. This technique would provide
the most precise information from the third generation about potential new
physics explanations of the muon anomaly. Additional and
QCD physics programs enabled or enhanced with having polarized electron beams
are also discussed in this White Paper. This paper includes a summary of the
path forward in R&D and next steps required to implement this upgrade and
access its exciting discovery potential.Comment: 74 pages, 56 figures, contribution to Snowmass 202
Snowmass 2021 White Paper on Upgrading SuperKEKB with a Polarized Electron Beam: Discovery Potential and Proposed Implementation
74 pages, 56 figures, contribution to Snowmass 2021Upgrading the SuperKEKB electron-positron collider with polarized electron beams opens a new program of precision physics at a center-of-mass energy of 10.58 GeV. This white paper describes the physics potential of this `Chiral Belle' program. It includes projections for precision measurements of that can be obtained from independent left-right asymmetry measurements of transitions to pairs of electrons, muons, taus, charm and b-quarks. The precision obtainable at SuperKEKB will match that of the LEP/SLC world average, but at the centre-of-mass energy of 10.58 GeV. Measurements of the couplings for muons, charm, and -quarks will be substantially improved and the existing discrepancy between the SLC and LEP measurements will be addressed. Precision measurements of neutral current universality will be more than an order of magnitude more precise than currently available. As the energy scale is well away from the -pole, the precision measurements will have sensitivity to the presence of a parity-violating dark sector gauge boson, . The program also enables the measurement of the anomalous magnetic moment form factor of the to be made at an unprecedented level of precision. A precision of level is accessible with 40~ab and with more data it would start to approach the level. This technique would provide the most precise information from the third generation about potential new physics explanations of the muon anomaly. Additional and QCD physics programs enabled or enhanced with having polarized electron beams are also discussed in this White Paper. This paper includes a summary of the path forward in R&D and next steps required to implement this upgrade and access its exciting discovery potential
Fano-Resonances in High Index Dielectric Nanowires for Directional Scattering
International audienceHigh refractive index dielectric nanostructures provide original optical properties thanks to the occurrence of size- and shape-dependent optical resonance modes. These modes commonly present a spectral overlap of broad, low-order modes (\textit{e.g}. dipolar modes) and much narrower, higher-order modes. The latter are usually characterized by a rapidly varying frequency-dependent phase, which - in superposition with the lower order mode of approximately constant phase - leads to typical spectral features known as Fano resonances. Interestingly, such Fano resonances occur in dielectric nanostructures of the simplest shapes. In spheroidal nanoparticles, interference between broad magnetic dipole and narrower electric dipole modes can be observed. In high aspect-ratio structures like nanowires, either the electric or the magnetic dipolar mode (depending on the illumination conditions) interferes with higher order multipole contributions of the same nature (electric or magnetic). Using the analytical Mie theory, we analyze the occurrence of Fano resonances in high-index dielectric nanowires and discuss their consequences like unidirectional scattering. By means of numerical simulations, we furthermore study the impact on those Fano resonances of the shape of the nanowire cross-sections as well as the coupling of two parallel nanowires. The presented results show that all-dielectric nanostructures, even of simple shapes, provide a reliable low-loss alternative to plasmonic nanoantennas