Download or read book Study of Lambda c Cabibbo Favored Decays Containing a Lambda Baryon in the Final State written by and published by . This book was released on 2005 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: Using data from the FOCUS experiment (FNAL-E831), they study the decay of ?{sub c}+ baryons into final states contain a ? hyperon. The branching fractions of ?{sub c}+ into ??+, ??+?+?− and ?{bar K}°K+ relative to that into pK− ?+ are measured to be 0.217 ± 0.013 ± 0.020, 0.508 ± 0.024 ± 0.024 and 0.142 ± 0.018 ± 0.022, respectively. New measurements are also reported. Further, an analysis of the subresonant structure for the ?{sub c}+ → ??+?+?− decay mode is presented.

Download or read book Measurement of Lambda C Branching Fractions of Cabibbo Suppressed Decay Modes in the BABAR Experiment written by Muhammad Saleem and published by . This book was released on 2006 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation reports on a study of the relative branching fraction measurement of the charmed baryon {Lambda}{sub c} decaying to the Cabibbo-suppressed modes.

Download or read book Measurement of Lambda C Branching Fractions of Cabibbo Suppressed Decay Modes in the BABAR Experiment written by Muhammad Saleem and published by . This book was released on 2006 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation reports on a study of the relative branching fraction measurement of the charmed baryon {Lambda}{sub c} decaying to the Cabibbo-suppressed modes.

Download or read book A Study of Charm Baryons Containing a Lambda Baryon in the Final State written by Joseph Alexander Swiatek and published by . This book was released on 1995 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Study of the Decay Properties of the Charmed Baryon Charmed Positive Lambda Baryon written by C.E.K. Charlesworth and published by . This book was released on 1992 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The charmed baryon $\Lambda\sbsp{c}{+}$ has been observed using the ARGUS detector in the DORIS II $e\sp{+}e\sp-$ storage ring at DESY. The ARGUS experiment is a 4$\pi$ magnetic solenoidal detector used to observe $e\sp{+}e\sp-$ annihilations at center-of-mass energies around 10.4 GeV. We have studied 5 decays modes of the $\Lambda\sbsp{c}{+}$. The decay mode $\Lambda\sbsp{c}{+}\to pK\sp-\pi\sp+$ was used to measure the $\Lambda\sbsp{c}{+}$ fragmentation properties. A value of 0.24 $\pm$ 0.04 was found for the Peterson et al. parameter $\epsilon$, and the $\sigma(\Lambda\sbsp{c}{+}$) $\cdot\ BR(\Lambda\sbsp{c}{+}\to pK\sp-\pi\sp+$) was measured to be 12.0 $\pm$ 1.1 $\pm$ 1.3) pb. The decay modes $\Lambda\sbsp{c}{+}\to\Lambda\pi\sp+$ and $\Lambda\sbsp{c}{+}\to\Sigma\sp0\pi\sp+$ were also studied. In the former the asymmetry parameter $\alpha\sb{\Lambda\sb{c}}$ was measured to be $-$1.0 $\pm$ 0.5, indicating that parity is maximally violated in this decay. The two production cross section times branching ratios were measured to be (2.2 $\pm$ 0.3 $\pm$ 0.3) pb and (2.0 $\pm$ 0.7 $\pm$ 0.3) pb respectively. Finally, a search was made for evidence of W-exchange in the decay $\Lambda\sbsp{c}{+}\to\Xi\sp-K\sp+\pi\sp+$. This final state can arise through a simple spectator decay or via the more exotic W-exchange decay into $\Xi\sp{*0}K\sp+$, where the $\Xi\sp{*0}$ subsequently decays into $\Xi\sp-\pi\sp+$. The two body rate was measured to be (35 $\pm$ 17)% of the three body rate, indicating that a significant portion of the $\Xi\sp-K\sp+\pi\sp+$ final state may occur via W-exchange.

Download or read book Searches for the Baryon and Lepton number Violating Decays B 0 rightarrow Lambda c ell B rightarrow Lambda ell and B rightarrow bar Lambda ell written by and published by . This book was released on 2011 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: Searches for B mesons decaying to final states containing a baryon and a lepton are performed, where the baryon is either [Lambda]{sub c} or [Lambda] and the lepton is a muon or an electron. These decays violate both baryon and lepton number and would be a signature of physics beyond the standard model. No significant signal is observed in any of the decay modes, and upper limits in the range (3.2 - 520) x 10−8 are set on the branching fractions at the 90% confidence level.

Download or read book Measurements of Lambda c Branching Fractions of Cabibbo Suppressed Decay Modes Involving Lambda and Sigma 0 written by J. C. Chen and published by . This book was released on 2006 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Semileptonic Decays of Heavy Lambda Baryons in a Quark Model written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The semileptonic decays of [Lambda]{sub c} and [Lambda]{sub b} are treated in the framework of a constituent quark model. Both nonrelativistic and semirelativistic Hamiltonians are used to obtain the baryon wave functions from a fit to the spectra, and the wave functions are expanded in both the harmonic oscillator and Sturmian bases. The latter basis leads to form factors in which the kinematic dependence on q2 is in the form of multipoles, and the resulting form factors fall faster as a function of q2 in the available kinematic ranges. As a result, decay rates obtained in the two models using the Sturmian basis are significantly smaller than those obtained using the harmonic oscillator basis. In the case of the [Lambda]{sub c}, decay rates calculated using the Sturmian basis are closer to the experimentally reported rates. However, we find a semileptonic branching fraction for the [Lambda]{sub c} to decay to excited [Lambda]* states of 11% to 19%, in contradiction with what is assumed in available experimental analyses. Our prediction for the [Lambda]{sub b} semileptonic decays is that decays to the ground state [Lambda]{sub c} provide a little less than 70% of the total semileptonic decay rate. For the decays [Lambda]{sub b} → [Lambda]{sub c}, the analytic form factors we obtain satisfy the relations expected from heavy-quark effective theory at the non-recoil point, at leading and next-to-leading orders in the heavy-quark expansion. In addition, some features of the heavy-quark limit are shown to naturally persist as the mass of the heavy quark in the daughter baryon is decreased.

Download or read book Production and Decay of the Lambda C Charmed Baryon from Fermilab E791 written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Results are presented for the 500 GeV/c pion production asymmetry and polarization of the [Lambda]{sub c} ({bar [Lambda]}{sub c}) charmed baryon from Fermilab experiment E791. An analysis of the decay to the p{bar K}[pi] final state is described. Resonant sub-channel fractions and phases are given and possible resonant effects in the low mass p{bar K} system discussed. Significant decay to {Lambda}{sub c} → [Delta]2K− establishes for the first time the importance of a W exchange mechanism in charmed baryon decay.

Download or read book Observation And Study of B Meson Decays with Lambda C Baryons with the BaBar Detector written by and published by . This book was released on 2013 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Measurements of Lambda sub C sup Branching Fractions of Cabibbo Suppressed Decay Modes written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors have measured the branching fractions of the Cabibbo-suppressed decays [Lambda][sub c][sup +] --> [Lambda][sup 0]K[sup +] and [Lambda][sub c][sup +] --> [Sigma][sup 0]K[sup +] relative to the Cabibbo-allowed decay modes [Lambda][sub c][sup +] --> [Lambda][sup 0][pi][sup +] and [Lambda][sub c][sup +] --> [Sigma][sup 0][pi][sup +] to be 0.044 [+-] 0.004 (stat.) [+-] 0.002 (syst.) and 0.040 [+-] 0.005 (stat.) [+-] 0.004 (syst.), respectively. They also present the first observation of [Lambda][sub c][sup +] --> [Lambda][sup 0]K[sup +][pi][sup +][pi][sup -] and have measured the branching fraction relative to [Lambda][sub c][sup +] --> [Lambda][sup 0][pi][sup +] to be 0.266 [+-] 0.027 (stat.) [+-] 0.032 (syst.). The upper limit of the branching fraction into the decay [Lambda][sub c][sup +] --> [Sigma][sup 0]K[sup +][pi][sup +][pi][sup -] relative to [Lambda][sub c][sup +] --> [Sigma][sup 0][pi][sup +] has been measured to be

Download or read book Charm Baryon Studies at BaBar written by V. Ziegler and published by . This book was released on 2006 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors present a precision measurement of the mass of the {Lambda}{sub c}{sup +} and studies of the production and decay of the {Omega}{sub c}{sup 0} and {Xi}{sub c}{sup 0} charm baryons using data collected by the BABAR experiment. To keep the systematic uncertainty as low as possible, the {Lambda}{sub c}{sup +} mass measurement is performed using the low Q-value decays, {Lambda}{sub c}{sup +} {yields} {Lambda}{sup 0} K{sub S}{sup 0}K{sup +} and {Lambda}{sub c}{sup +} {yields} {Sigma}{sup 0} K{sub S}{sup 0}K{sup +}. Several hadronic final states involving an {Omega}{sup -} and a {Xi}{sup -} hyperon are analyzed to reconstruct the {Xi}{sub c}{sup 0} and the {Omega}{sub c}{sup 0}.

Download or read book Measurements of Lambda sub C Branching Fractions of Cabibbo Suppressed Decay Modes written by and published by . This book was released on 2004 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors have measured the branching fractions of the Cabibbo-suppressed decays?{sub c} -->?°K+ and?{sub c}+ -->?°K+ relative to the Cabibbo-allowed decay modes?{sub c}+ -->?°?+ and?{sub c}+ -->?°?+ to be 0.044 ± 0.004 (stat.) ± 0.002 (syst.) and 0.040 ± 0.005 (stat.) ± 0.004 (syst.), respectively. They also present the first observation of?{sub c}+ -->?°K+?+?− and have measured the branching fraction relative to?{sub c}+ -->?°?+ to be 0.266 ± 0.027 (stat.) ± 0.032 (syst.). The upper limit of the branching fraction into the decay?{sub c}+ -->?°K+?+?− relative to?{sub c}+ -->?°?+ has been measured to be

Download or read book A Measurement of the Lambda c Baryon Decays to Proton Kaon Pion Absolute Branching Fraction with the BaBar Detector written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A measurement of [Beta]([Lambda][sub c][sup +] [yields] pK[sup -] [pi][sup +]) is presented based on data collected with the BaBar detector at the Stanford Linear Accelerator Center. Branching fraction measurements represent a large portion of what is known about short-lived particles, the strong force that binds them, and the weak force that causes them to decay. While the majority of branching fraction measurements are done as ratios between two decay modes, it is the absolute measurements of a few particular decay modes that set the scale for these relative measurements. The [Lambda][sub c][sup +] particle is one of the four weakly decaying hadrons into which more than 90% of the known heavy quark hadrons will eventually decay. Thus, an absolute measurement of the branching fraction for [Lambda][sub c][sup +] [yields] pK[sup -][pi][sup +] is important for many studies of the heavy quark sector, from spectroscopy to B meson decays. The number of produced [Lambda][sub c][sup +]'s is inferred from the number of events reconstructed with an antiproton and an accompanying D meson. The final result of [Beta]([Lambda][sub c][sup +] [yields] pK[sup -] [pi][sup +]) = [6.12 [+-] 0.31(stat.) [+-] 0.42(syst.)]% represents more than a two-fold improvement in precision over the world average. The dominant source of systematic uncertainty is the irreducible background of [Xi][sub c] baryons.

Download or read book Measurements of cal B overline B 0 to Lambda c overline p and cal B B to Lambda c overline p pi and Studies of Lambda c pi Resonances written by and published by . This book was released on 2008 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors present an investigation of the decays {bar B}° →?{sub c}{bar p} and B− →?{sub c}+{bar p}?− based on 383 x 106?(4S) → B{bar B} decays recorded with the BABAR detector. They measure the branching fractions of these decays; their ratio is?(B− →?{sub c}+{bar p}?−)/?({bar B}° →?{sub c}+{bar p}) = 15.4 ± 1.8 ± 0.3. The B− →?{sub c}+{bar p}?− process exhibits an enhancement at the?{sub c}+{bar p} threshold and is a laboratory for searches for excited charm baryon states. They observe the resonant decays B− →?{sub c}(2455)°{bar p} and B−?{sub c}(2800)°{bar p} but see no evidence for B− →?{sub c}(2520)°{bar p}. This is the first observation of the decay B− →?{sub c}(2800)°{bar p}; however, the mass of the observed excited?{sub c}° state is (2846 ± 8 ± 10) MeV/c2, which is somewhat inconsistent with previous measurements. Finally, they examine the angular distribution of the B− →?{sub c}(2455)°{bar p} decays and measure the spin of the?{sub c}(2455)° baryon to be 1/2, as predicted by the quark model.

Download or read book Search for Decays of the Lambda B Baryon written by and published by . This book was released on 2011 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Strange Decays of Nonstrange Baryons written by and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The strong decays of excited nonstrange baryons into the final states [Lambda]K, [Sigma]K, and for the first time into [Lambda](1405)K, [Lambda](1520)K, [Sigma](1385)K, [Lambda]K{sup *}, and [Sigma]K{sup *}, are examined in a relativized quark pair creation model. The wave functions and parameters of the model are fixed by previous calculations of N[pi] and N[pi][pi], etc., decays. The results show that it should be possible to discover several new negative parity excited baryons and confirm the discovery of several others by analyzing these final states in kaon production experiments. They also establish clear predictions for the relative strengths of certain states to decay to [Lambda](1405)K and [Lambda](1520)K, which can be tested to determine if a three-quark model of the [Lambda](1405)K is valid. The authors results compare favorably with the results of partial wave analyses of the limited existing data for the [Lambda]K and [Sigma]K channels. They do not find large [Sigma]K decay amplitudes for a substantial group of predicted and weakly established negative-parity states, in contrast to the only previous work to consider decays of these states into the strange final states [Lambda]K and [Sigma]K.