Download or read book Final Results from the KTeV Experiment on the Decay K L Pi0 Gamma Gamma written by and published by . This book was released on 2008 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors report on a new measurement of the branching ratio B(K{sub L} → [pi]°[gamma][gamma]) using the KTeV detector. They reconstruct 1982 events with an estimated background of 608, that results in B(K{sub L} → [pi]°[Gamma][gamma]) = (1.29 ± 0.03{sub stat} ± 0.05{sub syst}) x 10−6. They also measure the parameter, a{sub V}, which characterizes the strength of vector meson exchange terms in this decay. They find a{sub V} = -0.31 ± 0.05{sub stat} ± 0.07{sub syst}. These results utilize the full KTeV data set collected from 1997 to 2000 and supersede earlier KTeV measurements of the branching ratio and a{sub V}.
Download or read book Study on the Decay of KL to Pi0 Gamma Gamma written by Jianbo Wang and published by . This book was released on with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: We study on the rare decay
Download or read book Search for the Rare Decay K L Pi0 Pi0 Gamma written by and published by . This book was released on 2007 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Search for the Decay KL to Pi0 E E and Study of the Decay KL to E E Gamma Gamma written by Peter L. Mikelsons and published by . This book was released on 1999 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Measurement of the Branching Ratio of the pi 0 Dalitz Decay Using K L 2 3 pi 0 Decays from KTeV written by and published by . This book was released on 2007 with total page 183 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors present a measurement of B([pi]0 2!e+e-[gamma])/B([pi]0 2![gamma][gamma]) using data taken in 1999 by the E832 KTeV experiment at Fermilab. The [pi]0s were produced by KL decays in flight that are fully reconstructed. They find 63,693 KL 2!3[pi]0 2![gamma][gamma] [gamma][gamma] e+e-[gamma] decays in KTeV data (an increase of a factor of ~ 20 in event statistics over previous experiments), and normalize to KL 2!3[pi]0 2!6[gamma], to extract B([pi]0 2!e+e-[gamma], me+e-> 15 MeV/c2
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 Study of the Rare Decay K L Pi0 Gamma Gamma at KTeV written by and published by . This book was released on 2007 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors study on the rare decay K{sub L} 2![pi]°[gamma][gamma], measure a{sub V}, and branching ratio by analyzing 96, 97 and 99 data. The measurements were taken by KTeV at Fermi National Accelerator Laboratory. After all cuts, they have 1982 K{sub L} 2![pi]°[gamma][gamma] candidate. The background level is estimated as 30%. K{sub L} 2![pi]°[gamma][gamma] branching ratio is measured as (1.29 ± 0.03(stat) ± 0.04(sys)) x 10−6. By using D'Ambrosio's theory to fit a{sub V}, a{sub V} = -( -0.31 ± 0.05(stat) ± 0.07(sys)).
Download or read book Twist n Learn written by and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Epsilon prime epsilon and Rare KL Decays from KTeV Experiment written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors update the current status for the measurement of the direct-CP violation parameters????????/? in the KTeV experiment at Fermilab. Substantial statistics have been accumulated during the 1996-7 run and 1999 run for both????????/? and rare K{sub L} decay searches. The first KTeV result on????????/? published last year was Re(????????/?) = (28.0 ± 4.1) x 10{sup −4} based on the 23% data from 1996-7 run. Combining with the previous E731, NA31 and the recent preliminary NA48 results, the grand average is Re(????????/?) = (19.3 ± 3.6) x 10{sup −4} (with S = 1:49), more than 5? above zero. More data from both KTeV and NA48 after completing the analysis will further improve the precision of this measurement in the near future and hopefully further improve the agreement. New results on the branching ratio and form factor measurements of K{sub L} →??{sup −}? using 1997 data are also presented. We find that BR(K{sub L} →?+?{sup −}?) = (3.66 ± 0.04{sub stat} ± 0.07{sub syst}) x 10{sup −7}. The form factor parameter?{sub K}* is measured to be?{sub K}* = −0.157{sub −0.027}{sup +0.025}. We make the first measurement of the parameter? from the D'Ambrosio, Isidori, and Portoles form factor, finding? = −1.53 ± 0.09. This measurement of? limits the CKM parameter?> −0.2.
Download or read book Search for the Rare Decay K L right Arrow pi 0 pi 0 gamma written by David Edward Smith and published by . This book was released on 2006 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experimental Study of the Decay K arrow Leads to Right pi 0 E gamma written by Robert W. Garland and published by . This book was released on 1967 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Study of the K to Pi Pi0 Gamma Decays at the NA48 2 Experiment at the CERN SPS written by Silvia Goy López and published by . This book was released on 2006 with total page 201 pages. Available in PDF, EPUB and Kindle. Book excerpt: The NA48/2 experiment at the CERN SPS has collected a large sample of K to pi pi0 gamma decays.Two amplitudes contribute to these decays. The dominant one comes from Inner Bremsstrahlung (IB) in the K to pi pi0 process. The second one is given by the Direct Emission (DE) of the photon at the weak vertex from an intermediate state of the decay. The simplest radiative transitions are electric dipole (E1) and magnetic dipole (M1). Electric amplitudes can interfere with IB, and CP violation and possible non-SM effects can show up in th e corresponding interference (INT) term.In this work a sub sample of the data has been analyzed. About 120000 K to pi pi0 gamma decays, with negligible background contamination have been reconstructed in the ranges 0.2
Download or read book Dissertation Abstracts International written by and published by . This book was released on 2000 with total page 846 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A New Measurement of the Pi0 Radiative Decay Width written by and published by . This book was released on 2011 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: High precision measurements of the differential cross sections for $\pi^0$ photoproduction at forward angles for two nuclei, $^{12}$C and $^$Pb, have been performed for incident photon energies of 4.9 - 5.5 GeV to extract the ${\pi^0 \to \gamma\gamma}$ decay width. The experiment was done at Jefferson Lab using the Hall~B photon tagger and a high-resolution multichannel calorimeter. The ${\pi^0 \to \gamma\gamma}$ decay width was extracted by fitting the measured cross sections using recently updated theoretical models for the process. The resulting value for the decay width is $\Gamma{(\pi^0 \to \gamma\gamma)} = 7.82 \pm 0.14 ~({\rm stat.}) \pm 0.17 ~({\rm syst.}) ~{\rm eV}$. With the 2.8\% total uncertainty, this result is a factor of 2.5 more precise than the current PDG average of this fundamental quantity and it is consistent with current theoretical predictions.
Download or read book B Decays written by Sheldon Stone and published by World Scientific. This book was released on 1994 with total page 676 pages. Available in PDF, EPUB and Kindle. Book excerpt: This 2nd edition is an extensive update of "B Decays?. The revisions are necessary because of the extensive amount of new data and new theoretical ideas. This book reviews what is known about b-quark decays and also looks at what can be learned in the future.The importance of this research area is increasing, as evidenced by the approval of the luminosity upgrade for CESR and the asymmetric B factories at SLAC and KEK, and the possibility of experiments at hadron colliders.The key experimental observations made thus far, measurement of the lifetimes of the different B species, B0-B0 mixing, the discovery of ?Penguin? mediated decays, and the extraction of the CKM matrix elements Vub and Vcb from semileptonic decays, as well as more mundane results, are described in great detail by the experimentalists who have been closely involved with making the measurements. Theoretical progress in understanding b-quark decays using HQET and lattice gauge techniques are described by theorists who have developed and used these techniques.Synthesizing the experimental and theoretical information, several articles discuss the implications for the ?Standard Model? and how further tests can be done using measurements of CP violation in the B system.
Download or read book From the PS to the LHC 50 Years of Nobel Memories in High Energy Physics written by Luis Alvarez-Gaumé and published by Springer. This book was released on 2013-04-05 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This collection of lectures and essays by eminent researchers in the field, many of them nobel laureates, is an outgrow of a special event held at CERN in late 2009, coinciding with the start of LHC operations. Careful transcriptions of the lectures have been worked out, subsequently validated and edited by the lecturers themselves. This unique insight into the history of the field includes also some perspectives on modern developments and will benefit everyone working in the field, as well as historians of science.
Download or read book Dictionary of Medical Acronyms and Abbreviations written by Stanley Jablonski and published by Hanley & Belfus. This book was released on 2004-09 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dictionary lists acronyms and abbreviations occurring with a reasonable frequency in the literature of medicine and the health care professions. Abbreviations and acronyms are given in capital letters, with no punctuation, and with concise definitions. The beginning sections also include symbols, genetic symbols, and the Greek alphabet and symbols.
