10 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
Colour polymorphism and correlated characters: genetic mechanisms and evolution
Colour polymorphisms (CP’s) continue to be of interest to evolutionary biologists because of their general tractability, importance in studies of selection and potential role in speciation. Since some of the earliest studies of CP, it has been evident that alternative colour morphs often differ in features other than colour. Here we review the rapidly accumulating evidence concerning the genetic mechanisms underlying correlations between CP and other traits in animals. We find that evidence for genetic correlations is now available for taxonomically diverse systems and that physical linkage and regulatory mechanisms including transcription factors, cis-regulatory elements, and hormone systems provide pathways for the ready accumulation or modification of these correlations. Moreover, physical linkage and regulatory mechanisms may both contribute to genetic correlation in some of the best-studied systems. These results raise the possibility that negative frequency-dependent selection and disruptive selection might often be acting on suites of traits and that the cumulative effects of such selection, as well as correlational selection, may be important to CP persistence and evolution. We consider additional evolutionary implications. We recommend continued efforts to elucidate the mechanisms underlying CP-correlated characters and the more frequent application of comparative approaches, looking at related species that vary in character correlations and patterns of selection. We also recommend efforts to elucidate how frequency-dependent selection may act on suites of characters
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
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