Heavy Quark Lifetimes, Mixing and CP Violation

This paper emphasizes four topics that represent some of the year's highlights in heavy quark physics. First of all, a review is given of charm lifetime measurements and how they lead to better understanding of the mechanisms of charm decay. Secondly, the CLEO collaboration's new search for charm mixing is reported, which significantly extends the search for new physics in that sector. Thirdly, important updates in Bs mixing are summarized, which result in a new limit on the mass difference, and which further constrain the unitarity triangle. Finally, the first efforts to measure CP violation in the B system are discussed. Results are shown for the CDF and ALEPH measurements of sin(2beta), as well as the CLEO branching fraction measurements of B-->Kpi,pipi, which have implications for future measurements of alpha.Comment: 25 pages, 15 figures. Talk given at the XIX International Symposium on Lepton and Photon Interactions, Stanford University, August 9-14, 199

Interpreting experimental bounds on D^0 - \bar{D^0} mixing in the presence of CP violation

We analyse the most recent experimental data regarding D^0 - \bar{D^0} mixing, allowing for CP violation. We focus on the dispersive part of the mixing amplitude, M^D_{12}, which is sensitive to new physics contributions. We obtain a constraint on the mixing amplitude: |M^D_{12}| < 6.2\times 10^{-11} MeV at 95% C.L. . This constraint is weaker by a factor of about three than the one which is obtained when no CP violation is assumed.Comment: 9 pages, revtex4; One reference updated, one reference added, footnote 3 correcte

The EPR paradox, Bell's inequality, and the question of locality

Most physicists agree that the Einstein-Podolsky-Rosen-Bell paradox exemplifies much of the strange behavior of quantum mechanics, but argument persists about what assumptions underlie the paradox. To clarify what the debate is about, we employ a simple and well-known thought experiment involving two correlated photons to help us focus on the logical assumptions needed to construct the EPR and Bell arguments. The view presented in this paper is that the minimal assumptions behind Bell's inequality are locality and counterfactual definiteness, but not scientific realism, determinism, or hidden variables, as is often suggested. We further examine the resulting constraints on physical theory with an illustration from the many-worlds interpretation of quantum mechanics -- an interpretation that we argue is deterministic, local, and realist, but that nonetheless violates the Bell inequality.Comment: 28 pages; change of title, minor wording changes, move to TeX forma

Convalescent plasma in patients admitted to hospital with COVID-19 (RECOVERY): a randomised controlled, open-label, platform trial

SummaryBackground Azithromycin has been proposed as a treatment for COVID-19 on the basis of its immunomodulatoryactions. We aimed to evaluate the safety and efficacy of azithromycin in patients admitted to hospital with COVID-19.Methods In this randomised, controlled, open-label, adaptive platform trial (Randomised Evaluation of COVID-19Therapy [RECOVERY]), several possible treatments were compared with usual care in patients admitted to hospitalwith COVID-19 in the UK. The trial is underway at 176 hospitals in the UK. Eligible and consenting patients wererandomly allocated to either usual standard of care alone or usual standard of care plus azithromycin 500 mg once perday by mouth or intravenously for 10 days or until discharge (or allocation to one of the other RECOVERY treatmentgroups). Patients were assigned via web-based simple (unstratified) randomisation with allocation concealment andwere twice as likely to be randomly assigned to usual care than to any of the active treatment groups. Participants andlocal study staff were not masked to the allocated treatment, but all others involved in the trial were masked to theoutcome data during the trial. The primary outcome was 28-day all-cause mortality, assessed in the intention-to-treatpopulation. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936.Findings Between April 7 and Nov 27, 2020, of 16 442 patients enrolled in the RECOVERY trial, 9433 (57%) wereeligible and 7763 were included in the assessment of azithromycin. The mean age of these study participants was65·3 years (SD 15·7) and approximately a third were women (2944 [38%] of 7763). 2582 patients were randomlyallocated to receive azithromycin and 5181 patients were randomly allocated to usual care alone. Overall,561 (22%) patients allocated to azithromycin and 1162 (22%) patients allocated to usual care died within 28 days(rate ratio 0·97, 95% CI 0·87–1·07; p=0·50). No significant difference was seen in duration of hospital stay (median10 days [IQR 5 to >28] vs 11 days [5 to >28]) or the proportion of patients discharged from hospital alive within 28 days(rate ratio 1·04, 95% CI 0·98–1·10; p=0·19). Among those not on invasive mechanical ventilation at baseline, nosignificant difference was seen in the proportion meeting the composite endpoint of invasive mechanical ventilationor death (risk ratio 0·95, 95% CI 0·87–1·03; p=0·24).Interpretation In patients admitted to hospital with COVID-19, azithromycin did not improve survival or otherprespecified clinical outcomes. Azithromycin use in patients admitted to hospital with COVID-19 should be restrictedto patients in whom there is a clear antimicrobial indication

Sciphile.org — an Online Science Library for Teachers

Prof. Blaylock will demonstrate a website (http://sciphile.org) he has developed to help teachers and parents teach science. The site hosts a growing library of short science activities and lessons, which strive to complement traditional lectures with engaging in-class materials. For college teachers, the site offers a number of opportunities. At the most basic level, it can be source of inspiration for their own courses and a place to publish and share teaching materials they develop. Instructors can also use Sciphile.org as a laboratory for college students to contribute to a shared body of science education resources. Students can create materials, share them privately with instructors, and later submit them for general publication if they like. By publishing their work, students have the opportunity to receive public feedback and commentary and produce work with a legacy beyond the confines of the university course. Sciphile.org also allows several authors to collaborate on the same work, providing opportunities for group projects

Sciphile.org — an Online Science Library for Teachers

Prof. Blaylock will demonstrate a website (http://sciphile.org) he has developed to help teachers and parents teach science. The site hosts a growing library of short science activities and lessons, which strive to complement traditional lectures with engaging in-class materials. For college teachers, the site offers a number of opportunities. At the most basic level, it can be source of inspiration for their own courses and a place to publish and share teaching materials they develop. Instructors can also use Sciphile.org as a laboratory for college students to contribute to a shared body of science education resources. Students can create materials, share them privately with instructors, and later submit them for general publication if they like. By publishing their work, students have the opportunity to receive public feedback and commentary and produce work with a legacy beyond the confines of the university course. Sciphile.org also allows several authors to collaborate on the same work, providing opportunities for group projects

Direct measurement of the decays of charmed D mesons

Charmed D mesons produced in the decay of the t/1(3770) are observed by the Mark III detector at SPEAR. A new technique is applied to these data to derive D branching fractions which do not rely on the measurement of D production cross sections. Measurements are presented for three decay modes of the D0 ( K-1pi+, K-1pi-1pi+ 1pi+ and K-1pi+ 1pi0 ) and four decay modes of the n+ ( K-1pi+ 1pi+, K-1pi+1pi+1pi0 , K-1pi+ and K-1pi+1pi0 ). The resulting branching fractions are significantly larger than previous measurements.U of I OnlyThesi