This award provides continued one-year support for the heavy flavor-physics program of the experimental high-energy physics group at the University of Cincinnati (UC), Michael Sokoloff - PI. The intellectual merit focuses on key questions in Electroweak Symmetry Breaking and the potential existence of new particles. The proposed research using the BaBar data set will advance our understanding of Standard Model physics and provide students with opportunities to engage in high quality data analyses. The broader impact includes the education and mentoring of graduate and undergraduate students and continued involvement in the UC QuarkNet program as well as beneficial contributions in intensive computing and medical applications.
The primary purpose of this grant was to support efforts to bring analyses of data from the BaBar experiment to conclusion, Zahary Huard completed his Ph.D. dissertation research during this period: Precision measurement of the D*(2010)+ natural line width and D*(2010)+, D0 mass difference. (5/10/12). The results have been submited in short form to PRL (arXiv:1304.5657v1) and in archival form for PRD (arXiv:1304.5009v1). Cheryl Pappenheimer, an undergraduate, has essentially completed a precise measurement of the D0 mass using D0 → K- K- K+ π+ decays. She presented the results at the APS meeting in Denver in April 2013, and also at a topical group meeting a few days earlier. The draft paper is currently (May 2013) in Collaboration Wide Review, the last step before submission for publication. Phil Campos, another undergraduate, worked on a precise measurement of the D+ mass using D+ → K- K- K+ π+π+ decays. To our surprise, we observed no signal, indicating a significantly lower branching fraction than anticipated. Measuring an upper limit for this branching fraction using the BaBar data s a relatively low priority for us. We expect that the LHCb experiment (our next project) can do this at least as well with the data already recorded. Buddhi Pushpawela, a graduate student, is using BaBar data to measure D0 - antiD0 oscillations using D0 → K π π0 decays from the full dataset. This work is progressing, and we anticipate she will defend her dissertation no later than April 2014. Our group participated in the reviews of many BaBar analysess during the grant period. Brian Meadows served as Chair of the Collaboration Council. BaBar finished taking data in early 2008, and many of the subsequent analyses, including searches for CP violation in charm decays and studies of D0 - antiD0 mixing, are sensitive probes of physics beyond the Standard Model, also called New Physics (NP). To contue this field of research, we decided to join the LHCb experiment at CERN. Brian Meadows arranged to take his sabbatical working on LHCb at Oxford in the 2012-2013 academic year, and Michael Sokoloff began working on LHCb in late 2011 and 2012, during his sabbatical year. We have subsequently been supported by a new NSF grant to work on LHCb, and our post-doc and new students are working on that experiment while we finish analyses of BaBar data. Working with Jeff Rodriguez from Anderson High School, we sponsored QuarkNet programs for high school teachers and students during both years of this grant period (including the No-Cost-Extension). Summer Institutes for teachers were held each summer. Also, four high school students and one teacher spent six weeks doing research with us each year.