Search for the Rare Decay K(L) ---] Pi0 Pi0 Gamma


Book Description

The KTeV E799 experiment has conducted a search for the rare decay K{sub L} 2![pi]°°[gamma] via the topology K{sub L} 2![pi]°[pi]°{sub D}[gamma] (where [pi]°{sub D} 2![gamma]ee−). Due to Bose statistics of the [pi]° pair and the real nature of the photon, the K{sub L} 2![pi]°[pi]°[gamma] decay is restricted to proceed at lowest order by the CP conserving direct emission (DE) of an E2 electric quadrupole photon. The rate of this decay is interesting theoretically since chiral perturbation theory predicts that this process vanishes at level O(p4). Therefore, this mode probes chiral perturbation theory at O(p6). In this paper we report a determination of an upper limit of 2.43 x 10−7 (90% CL) for K{sub L} 2![pi]°[pi]°[gamma]. This is approximately a factor of 20 lower than previous results.










Probabilistic Reliability Engineering


Book Description

With the growing complexity of engineered systems, reliability hasincreased in importance throughout the twentieth century. Initiallydeveloped to meet practical needs, reliability theory has become anapplied mathematical discipline that permits a priori evaluationsof various reliability indices at the design stages. Theseevaluations help engineers choose an optimal system structure,improve methods of maintenance, and estimate the reliability on thebasis of special testing. Probabilistic Reliability Engineeringfocuses on the creation of mathematical models for solving problemsof system design. Broad and authoritative in its content, Probabilistic ReliabilityEngineering covers all mathematical models associated withprobabilistic methods of reliability analysis, including--unique tothis book--maintenance and cost analysis, as well as many newresults of probabilistic testing. To provide readers with all necessary background material, thistext incorporates a thorough review of the fundamentals ofprobability theory and the theory of stochastic processes. Itoffers clear and detailed treatment of reliability indices, thestructure function, load-strength reliability models, distributionswith monotone intensity functions, repairable systems, the Markovmodels, analysis of performance effectiveness, two-pole networks,optimal redundancy, optimal technical diagnosis, and heuristicmethods in reliability. Throughout the text, an abundance of realworld examples and case studies illustrate and illuminate thetheoretical points under consideration. For engineers in design, operations research, and maintenance, aswell as cost analysts and R&D managers, ProbabilisticReliability Engineering offers the most lucid, comprehensivetreatment of the subject available anywhere. About the editor JAMES A. FALK is Professor and Chairman of the Department ofOperations Research at George Washington University. In addition tohis numerous publications, Dr. Falk has lectured internationally asa Fulbright Lecturer. Of related interest... The reliability-testing "bible" for three generations of EasternEuropean scientists, adapted for Western scientists andengineers... HANDBOOK OF RELIABILITY ENGINEERING Originally published in the USSR, Handbook of ReliabilityEngineering set the standard for the reliability testing oftechnical systems for nearly three generations of appliedscientists and engineers. Authored by a group of prominent Sovietspecialists in reliability, it provides professionals and studentswith a comprehensive reference covering mathematical formulas andtechniques for incorporating reliability into engineering designsand testing procedures. Divided into twenty-four self-containedchapters, the Handbook details reliability fundamentals, examinescommon reliability problems and solutions, provides a collection ofcomputation formulas, and illustrates practical applications. The Handbook's Russian editor and internationally recognized expertIgor A. Ushakov has joined with American engineering professionalsto bring this indispensable resource to English-speaking engineersand scientists. 1994 (0-471-57173-3) 663 pp.




Search For the Rare Decay K(L) ---] Pi0 Pi0 Gamma


Book Description

This thesis describes a search for the rare decay K{sub L} {yields} {pi}{sup 0}{pi}{sup 0}{gamma} using data from the KTeV experiment, using the topology K{sub L} {yields} {pi}{sup 0}{pi}{sub D}{sup 0}{gamma} (where {pi}{sub D}{sup 0} {yields} {gamma}e{sup +}e{sup -}). Due to Bose statistics and the real nature of the photon, the K{sub L} {yields} {pi}{sup 0}{pi}{sup 0}{gamma} decay can proceed at lowest order only by the Cp conserving direct emission of an E2 photon. The decay vanishes to O(p{sup 4}) in chiral perturbation theory and is a probe of the theory to the sixth order. The primary background to this decay consists of K{sub L} {yields} {pi}{sup 0}{pi}{sup 0}{pi}{sub D}{sup 0} events with one lost photon. The upper limit for the decay K{sub L} {yields} {pi}{sup 0}{pi}{sup 0}{gamma} presented in this thesis is 2.32 x 10{sup -7} at the 90% confidence level. This upper limit was derived from both 1997 and 1999 data, using a blind analysis. The upper limit was derived from a Feldman-Cousins method, based on a weighted total of 0.53 data events in the signal region with an expected K{sub L} {yields} {pi}{sup 0}{pi}{sup 0}{pi}{sub D}{sup 0} background of 0.37 {+-} 0.28 events. The previous upper limit for this decay was 5.6 x 10{sup -6} at the 90% confidence level.