Download or read book The K Pi S wave from the D K Pi Pi Decay written by and published by . This book was released on 2009 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Study of the S wave K pi 2 Amplitude Using the Decay D 2 K pi pi written by and published by . This book was released on 2007 with total page 145 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this work the S-wave component of the K[pi] amplitude from decay of D+ → K+[pi]+[pi]+ it is directly measured. The data come from the Fermilab E831/FOCUS experiment. The amplitude measurement is made using the partial wave analysis without any preliminary assumption about the nature of the S-wave component of the K[pi] system. The phase and magnitude of the S-wave amplitude are generic functions to be determined directly through the Dalitz plot fit. For the sake of comparison, our results the same decay is analyzed using the isobar model, which is the standard way to analyze the Dalitz plot. The data fit obtained with the partial wave analysis is better than the data fit from the isobar model. The phase variation with respect to the invariant mass K[pi] is compared with the measurement of the phase [Delta]$0\atop{I=1/2}$ (mK[pi]) from K[pi] → K[pi] scattering. The difference between both analysis is discussed considering: a difference in the composition of the isospin components I = 1/2 and I = 3/2 of the K[pi] system between D+ decay and the K[pi] → K[pi] scattering; and the final state interaction involving all particles from decay.
Download or read book Simultaneous Measurement of KS and KL Decays Into written by and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: With the E731 apparatus at Fermilab, we have simultaneously collected 6859 K(L) and K(S) decays into pi+pi-gamma. Using our sample of over 370000 pi+pi- decays for normalization we have determined that the ratio GAMMA(K0 --> pi+pi-gamma)/GAMMA(K0 --> pi+pi- ) is (23.0 +/- 0.7) x 10( -3) for K(L) and (7.10 +/- 0.22) x 10( -3) for K(S), for photon energies greater than 20 MeV in the kaon center of mass. After removing the inner-bremsstrahlung contribution, we find that the photon energy spectrum of the direct emission decay of the K(L) is consistent with the presence of a vector meson propagator in the form factor.
Download or read book Determination of the S Wave Pi Pi Scattering Lengths From a Study of K to Pi Pi0 Pi0 Decays written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We report the results from a study of the full sample of ≈6.031 x 107 K{sup {+-}} →?{sup {+-}}?°?° decays recorded by the NA48/2 experiment at the CERN SPS. As first observed in this experiment, the?°?° invariant mass (M00) distribution shows a cusp-like anomaly in the region around M00 = 2m+, where m+ is the charged pion mass. This anomaly has been interpreted as an effect due mainly to the final state charge exchange scattering process??− →?°?° in K{sup {+-}} →?{sup {+-}}?+?− decay. Fits to the M00 distribution using two different theoretical formulations provide the presently most precise determination of a0 - a2, the difference between the?? S-wave scattering lengths in the isospin I = 0 and I = 2 states. Higher-order?? rescattering terms, included in the two formulations, allow also an independent, though less precise, determination of a2.
Download or read book Phase Motion of the Scalar pi pi Amplitudes in D sup D sub S sup yields pi sup pi sup pi sup Decays written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We make a direct and model-independent measurement of the low[pi][sup+][pi][sup -] mass phase motion in the D[sup+][yields][pi][sup -][pi][sup+][pi][sup+] decay. Our preliminary results show a strong phase variation, compatible with the isoscalar[sigma](500) meson. This result confirms our previous result[1] where we found evidence for the existence of this scalar particle using full Dalitz-plot analysis. We apply the Amplitude Difference (AD) method[2] to the same Fermilab E791 data sample used in the preceding analysis. We also give an example of how we extract the phase motion of the scalar amplitude, looking at the f[sub 0](980) in D[sub s][sup+][yields][pi][sup -][pi][sup+][pi][sup+] decay.
Download or read book CP Violation in B s 0 J psi phi Decays written by Sabato Leo and published by Springer. This book was released on 2014-07-24 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis reports on the final measurement of the flavor-mixing phase in decays of strange-bottom mesons (B_s) into J/psi and phi mesons performed in high-energy proton-antiproton collisions recorded by the Collider Experiment at Fermilab. Interference occurs between direct decays and decays following virtual particle-antiparticle transitions (B_s-antiB_s). The phase difference between transition amplitudes (“mixing phase”) is observable and extremely sensitive to contributions from non-standard-model particles or interactions that may be very hard to detect otherwise – a fact that makes the precise measurement of the B_s mixing phase one of the most important goals of particle physics. The results presented include a precise determination of the mixing phase and a suite of other important supplementary results. All measurements are among the most precise available from a single experiment and provide significantly improved constraints on the phenomenology of new particles and interactions.
Download or read book Measurement of the Decay UPSILON 2S Pi Pi UPSILON 1S written by and published by . This book was released on 1985 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The hadronic transitions UPSILON(2S) .-->. .pi.°.pi. UPSILON(1S) .-->. .gamma gamma gamma gamma.ll− (l = .mu. or e) are investigated using the Crystal Ball detector. The analysis is based on 193,000 UPSILON(2S) events produced at the DORIS II ee− storage ring from November 1982 to February 1984. We observe 44 events with a muon pair and 46 events with an electron pair in the final state. The signals in both channels are relatively background free. Assuming lepton universality, we average the results for the two channels and obtain the product branching ratio B(UPSILON(2S) .-->. .pi.°.pi.°UPSILON(1S)) x B/sub ll/(UPSILON(1S)) = (2.3 +- 0.3 +- 0.3) x 10−3 where the first error is statistical and the second is systematic. Using the present world average value of B/sub ll/(UPSILON(1S)) = (2.9 +- 0.3)% we derive a branching ratio B(UPSILON(2S) .-->. .pi.°.pi.°UPSILON(1S)) = (8.0 +- 1.5)% where the statistical and systematic errors have been added in quadrature. This result is compared with previous results for the charged pion transitions UPSILON(2S) .-->. .pi.+.pi.−UPSILON(1S) and with the expectation from theory. We have also investigated the mass spectrum M/sub .pi.°.pi.°/ resulting from these decays and find a peaking toward high masses not accounted for the phase space alone. Fits to the .pi.°.pi.° mass spectrum are in quantitative agreement with previous results for the .pi.+.pi.− transitions. Angular distribution for the .pi.°.pi.° system and its decay products are presented in reference frames appropriate for analyzing the spin of the .pi.°.pi.° system, even if the initial UPSILON(1S) and the di-pion system are emitted in a relative S-wave. We find the decay distributions to be consistent with those expected for a spin zero di-pion system emitted in a relative S-wave with the UPSILON(1S).
Download or read book Dalitz Plot Analysis of Ds pi pi pi written by and published by . This book was released on 2009 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: A Dalitz plot analysis of ≈ 13, 000 D{sub s} decays to?+?+?− has been performed. A 384 fb−1 data sample, recorded by the BABAR detector at the PEP-II asymmetric-energy e+e− storage ring running at center of mass energies near 10.6 GeV, is used. Amplitudes and phases of the intermediate resonances which contribute to this final state are measured. A high precision measurement of the ratio:?(D{sub s}+ →?+?+?−)/?(D{sub s}+ → K+K−?+) = 0.199 ± 0.004 ± 0.006 is performed. Using a model independent partial wave analysis the amplitude and phase of the S-wave have been measured.
Download or read book Study of the D0 K K Pi Pi written by and published by . This book was released on 2004 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: Using data from the FOCUS (E831) experiment at Fermilab, the authors present a new measurement for the Cabibbo-suppressed decay mode D° 2!KK−?+?−. They measure:?(D° 2!K+K−?+?−)/?(D° 2!K−?−?+?+) = 0.0295 ± 0.0011 ± 0.0008. An amplitude analysis has been performed in order to determine the resonant substructure of this decay mode. The dominant components are the decays D° 2!K1(1270)+ K−, D° 2!K1(1400)+K− and D° 2!?(770)°?(1020).
Download or read book Measurement of the K Pi Pi E V E Form Factors and of the Pi Pi Scattering Length a 0 0 written by and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The quark condensate is a fundamental free parameter of Chiral Perturbation Theory ($chi PT$), since it determines the relative size of the mass and momentum terms in the power expansion. In order to confirm or contradict the assumption of a large quark condensate, on which $chi PT$ is based, experimental tests are needed. In particular, the $S$-wave $pipi$ scattering lengths $a_0^0$ and $a_0^2$ can be predicted precisely within $chi PT$ as a function of this parameter and can be measured very cleanly in the decay $K^{pm} to pi^{+} pi^{-} e^{pm} stackrel{mbox{tiny( --- )}}{nu_e}$ ($K_{e4}$). About one third of the data collected in 2003 and 2004 by the NA48/2 experiment were analysed and 342,859 $K_{e4}$ candidates were selected. The background contamination in the sample could be reduced down to 0.3% and it could be estimated directly from the data, by selecting events with the same signature as $K_{e4}$, but requiring for the electron the opposite charge with respect to the kaon, the so-called ``wrong sign'' events. This is a clean background sample, since the kaon decay with $Delta S=-Delta Q$, that would be the only source of signal, can only take place through two weak decays and is therefore strongly suppressed. The Cabibbo-Maksymowicz variables, used to describe the kinematics of the decay, were computed under the assumption of a fixed kaon momentum of 60 GeV/$c$ along the $z$ axis, so that the neutrino momentum could be obtained without ambiguity. The measurement of the form factors and of the $pipi$ scattering length $a_0^0$ was performed in a single step by comparing the five-dimensional distributions of data and MC in the kinematic variables. The MC distributions were corrected in order to properly take into account the trigger and selection efficiencies of the data and the background contamination. The following parameter values were obtained from a binned maximum likelihood fit, where $a_0^2$ was expressed as a function of $a_0^0$ according to the predict.
Download or read book Study of the D0 Pi Pi Pi Pi Decay written by and published by . This book was released on 2007 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: Using data from the FOCUS (E831) experiment at Fermilab, they present new measurements for the Cabbibo-suppressed decay mode D° →?−??−?+. They measure the branching ratio?(D° →?+?−?+?−)/?(D° → K−?+?−?+) = 0.0914 ± 0.0018 ± 0.0022. An amplitude analysis has been performed, a first for this channel, in order to determine the resonant substructure of this decay mode. The dominant component is the decay D° → a1(1260)+?−, accounting for 60% of the decay rate. The second most dominant contribution comes from the decay D° →?(770)°?(770)°, with a fraction of 25%. They also study the a1(1260) line shape and resonant substructure. Using the helicity formalism for the angular distribution of the decay D° →?(770)°?(770)°, they measure a longitudinal polarization of P{sub L} = (71 ± 4 ± 2)%.
Download or read book Ambiguity Free Measurement of Cos2beta written by B. Aubert and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We present results on B {yields} J/{psi} K{pi} decays using e{sup +}e{sup -} annihilation data collected with the BABAR detector at the {Upsilon}(4S) resonance. The detector is located at the PEP-II asymmetric-energy storage ring facility at the Stanford Linear Accelerator Center. Using approximately 88 million B{bar B} pairs, we measure the decay amplitudes for the flavor eigenmodes and observe strong-phase differences indicative of final-state interactions with a significance of 7.6 standard deviations. We use the interference between the K{pi} S-wave and P-wave amplitudes in the region of the K*(892) to resolve the ambiguity in the determination of these strong phases. We then perform an ambiguity-free measurement of cos 2{beta} using the angular and time-dependent asymmetry in B {yields} J/{psi} K*{sup 0} (K{sub S}{sup 0}{pi}{sup 0}) decays. With sin2{beta} fixed at its measured value and cos2{beta} treated as an independent parameter, we find cos 2{beta} = 2.72{sub -0.79}{sup +0.50}(stat) {+-} 0.27(syst), determining the sign of cos 2{beta} to be positive at 86% CL.
Download or read book A partial wave analysis of the decay D K s K s pi pi written by and published by . This book was released on 1993 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Measurement of the Branching Ratio of K pi mu mu Decays in the Hyper CP Experiment written by and published by . This book was released on 2001 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Large samples of hyperon and kaon decays were collected with the Hyper CP spectrometer during two fixed-target runs at Fermilab. Based on an analysis of 110 million K pm decays from the 1997 data sample we present a branching ratio for K pm right arrow pi pm mu+ mu-. This is the first observation of K- right arrow pi- mu+ mu- decay.
Download or read book Partial Wave Analysis of the low mass K pi pi systems produced diffractively and by Charge exchange in 4 2 GeV c K p interactions written by Joris Stanislaus Maria Vergeest and published by . This book was released on 1979 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Production of Pi Pi K K P and Pbar in Light uds C and B Jets from Z0 Decays written by K. Abe and published by . This book was released on 2003 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present improved measurements of the differential production rates of stable charged particles in hadronic Z{sup 0} decays, and of charged pions, kaons and protons identified over a wide momentum range using the SLD Cherenkov Ring Imaging Detector. In addition to flavor-inclusive Z{sup 0} decays, measurements are made for Z{sup 0} decays into light (u, d, s), c and b primary flavors, selected using the upgraded Vertex Detector. Large differences between the flavors are observed that are qualitatively consistent with expectations based upon previously measured production and decay properties of heavy hadrons. These results are used to test the predictions of QCD in the Modified Leading Logarithm Approximation, with the ansatz of Local Parton-Hadron Duality, and the predictions of three models of the hadronization process. The light-flavor results provide improved tests of these predictions, as they do not include the contribution of heavy-hadron production and decay; the heavy-flavor results provide complementary model tests. In addition we have compared hadron and antihadron production in light quark (as opposed to antiquark) jets. Differences are observed at high momentum for all three charged hadron species, providing direct probes of leading particle effects, and stringent constraints on models.
Download or read book Partial Wave Analysis of the Low mass K Pi Pi Systems Produced Diffractively and by Charge exchange in 4 2 GeV c K p Interactions written by Joris Stanislaus Maria Vergeest and published by . This book was released on 1979 with total page 109 pages. Available in PDF, EPUB and Kindle. Book excerpt:
