Download or read book A Search for K Sup Yields Pi Sup Nu Nu and Other Rare K Sup Decays written by and published by . This book was released on 1990 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book SEARCH FOR THE RARE KAON DECAY K sup yields pi sup nu bar nu written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis describes the search for the rare decay K[sup+][yields][pi][sup+][nu][bar[nu]] in the pion momentum region 140 MeV/c[le] P[sub[pi][sup+]][le] 195 MeV/c. This is a Flavor Changing Neutral Current (FCNC) decay which is forbidden to the first order in the Standard Model (SM) by the GIM mechanism. However, this decay mode is allowed in the second order by two Z-Penguin and one box diagram and is expected to have a branching ratio of (0.72[+-] 0.21) x 10[sup -10]. This decay mode is sensitive to the coupling of top to down quark and therefore a measurement of the branching ratio for this decay mode provides a measurement of the Cabibbo-Kobayashi-Maskawa matrix element V[sub td]. The recent observation of two events in the pion momentum region 211 MeV/c[le] P[sup[pi][sup+]][le] 229 MeV/c estimates a branching ratio of 1.57[sub -0.82][sup+1.75] x 10[sup -10] for the same decay mode. We have extended the search for this decay to the lower pion momentum region. Data collected by the Experiment E787 at Brookhaven National Laboratory during the 1996 and 1997 run were analyzed in this thesis.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book g om trie variable written by and published by . This book was released on 1986 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Annual Index written by and published by . This book was released on with total page 1720 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sections 1-2. Keyword Index.--Section 3. Personal author index.--Section 4. Corporate author index.-- Section 5. Contract/grant number index, NTIS order/report number index 1-E.--Section 6. NTIS order/report number index F-Z.

Download or read book Cities and Their Vital Systems written by Advisory Committee on Technology and Society and published by National Academies Press. This book was released on 1989 with total page 1298 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cities and Their Vital Systems asks basic questions about the longevity, utility, and nature of urban infrastructures; analyzes how they grow, interact, and change; and asks how, when, and at what cost they should be replaced. Among the topics discussed are problems arising from increasing air travel and airport congestion; the adequacy of water supplies and waste treatment; the impact of new technologies on construction; urban real estate values; and the field of "telematics," the combination of computers and telecommunications that makes money machines and national newspapers possible.

Download or read book Energy Research Abstracts written by and published by . This book was released on 1990 with total page 852 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Search for the Flavor changing Neutral Current Decay K Sup Yields Pi Sup Nu Nu written by and published by . This book was released on 1990 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: The observation that flavor-changing neutral currents (FCNC) in weak decays are highly suppressed was first explained by Glashow, Iliopoulos and Maiani in 1970, and their idea has since become a cornerstone of the Standard Model. They proposed a model of the weak interaction that included a then new fourth quark and which, in a natural way, allowed the existence of a neutral vector boson without inducing FCNC's at tree level. Thus the couplings of the neutral intermediary{hor ellipsis}cause no embarrassment.'' In higher order through, decays like K →?l{bar l} can proceed. Measurements of such processes provide a detailed test of the Standard Model since definite predictions for their rates can be calculated. Conversely, if no contradictions are found and the standard model is assumed to describe the physics, measurements limit the allowed values of the parameters of the model. As is often the case in studying processes that are highly suppressed and heretofore unseen, improvements in the sensitivity of experiments allow the possibility for the discovery of new physics that exhibits a similar experimental signature. This paper describes experiment 787 at Brookhaven which is expected to address some of these issues. The status and future of the experiment will be described here. The main goal of E787 is to measure the rate of K →?+?{bar {nu}} at the standard model level. In addition, the experiment has sensitivity to other FCNC decays of the charged kaon, in particular the decays K+ →?+?+?− and K+ →?+??

Download or read book Government Reports Announcements Index written by and published by . This book was released on 1993 with total page 1032 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Search For the Rare Decay K L Pi0 Pi0 Gamma written by David Edward Smith and published by . This book was released on 2006 with total page 141 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book 919 Evidence for K sup r arrow pi sup nu bar nu from E787 written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A collaboration from KEK, INS, Osaka, TRIUMF, Princeton, and BNL is currently running E787 at the AGS. The experiment is designed primarily to search for the rare decay K[sup+][yields][pi][sup+][nu][bar[nu]], with an expected branching ratio of[approximately] 10[sup[minus]10]. The authors report evidence that they have observed this decay. They also discuss the future outlook for the experiment.

Download or read book Study of the Decay K L Pi E Nu E E to Probe the Semileptonic K pi Structure written by Katsushige Kotera and published by . This book was released on 2006 with total page 135 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors observed a new neutral kaon decay mode, K{sub L} {yields} {pi}{sup {+-}}e{sup {-+}}{bar {nu}}e{sup +}e{sup -} for the first time. Based on the 20225 events including 1018 {+-} 25 background events, they determined the branching ratio, B(K{sub L} {yields} {pi}{sup {+-}}e{sup {-+}}{bar {nu}}e{sup +}e{sup -}; M{sub e{sup +}e{sup -}}> 5 MeV/c{sup 2}, E*{sub e{sup +}e{sup -}}> 30 MeV) = (1.281 {+-} 0.041) x 10{sup -5}. This branching ratio agrees with a theoretical prediction based on the chiral perturbation theory ({chi}PT) calculation at {Omicron}(p{sup 4}). Most of the kinematical distributions agree with the {chi}PT {Omicron}(p{sup 4}) calculation. They also measured one of the low energy coupling constants for the {chi}PT {Omicron}(p{sup 4}), L{sub 9}{sup r} = (8.0 {+-} 1.6) x 10{sup -3}. The M{sub e{sup +}e{sup -}} distribution below 100 MeV showed a 3 {sigma} deviation from the {chi}PT {Omicron}(p{sup 4}) calculation. This requires further studies in theory and experiments.

Download or read book Search for the Decay K Sub L Sup 0 Yields Pi Sup 0 E Sup E Sup Minus written by and published by . This book was released on 1990 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: Results are presented of a recent search by AGS Experiment 845 for the CP violating decay K{sub L}° →?°ee−. The 90% C.L. limit B(K{sub L}° →?°e+e−)

Download or read book E787 a Search for the Rare Decay K sup written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent results from the first phase of the E787 experiment and an update on the current status are presented. From the first phase the limit on the K[sup+][r-arrow][pi][sup+][nu][ovr[nu]] branching ratio is BR(K[sup+][r-arrow][pi][sup+][nu][ovr[nu]])

Download or read book Search for the Decay K sub L 0 Yields Pi sup 0 e e written by and published by . This book was released on 1990 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Annual Index Keyword A L written by and published by . This book was released on 1987 with total page 1260 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book EXPERIMENTAL STATUS OF K YIELDS PVV written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The experimental program for the study of the rare kaon decays, K+[pi][nu][bar[nu]] is summarized. A review of recent results is provided along with a discussion of prospects for the future of this program. The primary focus of the world-wide kaon program is the two golden modes: K[sup+][yields][pi][sup+][nu][bar[nu]] and K[sub L][sup o][yields][pi][sup o][nu][bar[nu]]. The first step in an ambitious program to precisely measure both branching ratios has been successfully completed with the observation of two K[sup+][yields][pi][sup+][nu][bar[nu]] events by E787. The E949 experiment is poised to reach an order of magnitude further in sensitivity and to observe[approx]10 Standard Model events, and the CKM experiment should observe[approx]100 SM events by the end of this decade. Limits on the neutral analog K[sub L][sup o][yields][pi][sup o][nu][bar[nu]] have been set by KTeV and within the next couple of years will be pushed by E391a. Measurements of the branching ratio should be made within the next 10 years by KOPIO, with a goal of[approx]50 events, and at the JHF, with a goal of up to 1000 events.