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Backgrounds to 7 studies below charm threshold
| Content Provider | Semantic Scholar |
|---|---|
| Author | Kirkby, Jasper |
| Copyright Year | 1989 |
| Abstract | Using DELCO data obtained at SPEAR, we evaluate the backgrounds to r+rdata samples below open charm threshold at the r-charm Factory (TcF). With a singletagging signature (electron and missing energy, Emiss), which is unique to the rcF, the backgrounds are found to be below 0.1%. 1 Requirements for future T data samples In order to make significant progress in r physics, future data samples must have: 1. high statistics, 2. low backgrounds, and 3. reduced systematic biases. The precisions of current measurements are limited by one or more of these aspects. For example, searches for rare decays are generally limited only by statistics, whereas an improved sensitivity to the v, mass requires both more statistics and a reduction of heavyflavour backgrounds. On the other hand, present measurements of the exclusive one-prong branching ratios are limited by systematics and backgrounds and by the need for better detector performance, rather than by statistics. The r-charm Factory attacks each of these three present limitations as follows: 1. Large increase in statistics: the yearly rate exceeds the total present data by two orders of magnitude. 2. Elimination of heavy flavour backgrounds by operating below 00 threshold (3.73 GeV); at th ese energies, T decay is the only sourc.e of prompt leptons. Furthermore, all non-7 backgrounds are internally calibrated by taking data below T+Tthreshold (3.57 GeV). 3. Single-tagging of rSrevents, e.g. e + Emissa This imposes no requirements on the decay of the second r, thereby permitting a bias-free study of its decay. Furthermore, single-tagging allows absolute branching ratios to be measured, without the need for assumptions of the T+Tcross-section or measurements of the luminosity. The combination of these features, which are described below in more detail, provides the r-charm Factory with a sensitivity to precise and rare T physics that is unmatched elsewhere. |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | http://www.slac.stanford.edu/pubs/slacreports/reports02/tau89-032.pdf |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
