Download or read book Charmed Baryon Decays Observed in Ee Annihilation at SPEAR written by and published by . This book was released on 1981 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Various weak decays of the charmed baryon ..lambda../sub c/ are observed in the Mark II detector at the SLAC ee− storage ring SPEAR. Hadronic decays ..lambda../sub c/ ..-->.. pK−..pi..+ and ..lambda../sub c/+ ..-->.. pK/sub s/° and their conjugates are observed as peaks in invariant mass spectra at m(..lambda../sub c/) = (2286 +- 6) MeV/c2. An estimate of the charmed baryon production cross section, sigma(..lambda../sub c/) + sigma (anti ..lambda../sub c/) = (1.7 +- 0.4) nb, derived from Mark II measurements of the inclusive baryon cross sections R/sub p/ and R/sub ..lambda../ as functions of center-of-mass energy, is used to calculate branching ratios for these hadronic decays: BR (..lambda../sub c/+ ..-->.. p K− ..pi..+) = (2.0 +- 0.8)%; BR (..lambda../sub c//sup +/ ..-->.. p k/sub s/°)/BR (..lambda../sub c//sup +/ ..-->.. p K− ..pi../sup +/) = (36 +- 16)%. An attempt is also made to observe higher mass charmed baryons by reconstructing cascade decays ..sigma../sub c/ ..-->.. ..lambda../sub c/..pi ... Evidence for the observation of semileptonic decays of the charmed baryon is presented. Direct electrons are observed in events containing antiprotons, lambdas and antilambdas. The number of electrons per baryon event, after background subtraction and efficiency correction, is used, together with an estimate of the charmed baryon content of proton and lambda events, to calculate inclusive and semi-inclusive semileptonic branching ratios of the ..lambda../sub c.
Download or read book Charmed Baryon Decays Observed in E e Annihilation at SPEAR written by Eric Nelson Vella and published by . This book was released on 1982 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Observation of a Charmed Baryon Decaying to D0 P at a Mass Near 2 94 GeV c2 written by B. Aubert and published by . This book was released on 2006 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: A search for charmed baryons decaying to D{sup 0}p reveals two states: the {Lambda}{sub c}(2880){sup +} baryon and a previously unobserved state at a mass of [2939.8 {+-} 1.3 (stat.) {+-} 1.0 (syst.)] MeV/c{sup 2} and with an intrinsic width of [17.5 {+-} 5.2 (stat.) {+-} 5.9 (syst.)] MeV. Consistent and significant signals are observed for the K{sup -}{pi}{sup +} and K{sup -}{pi}{sup +}{pi}{sup -}{pi}{sup +} decay modes of the D{sup 0} in 287 fb{sup -1} annihilation data recorded by the BABAR detector at a center-of-mass energy of 10.58 GeV. There is no evidence in the D{sup +}p spectrum of doubly-charged partners. The mass and intrinsic width of the {Lambda}{sub c}(2880){sup +} baryon and relative yield of the two baryons are also measured.
Download or read book Observation of an Excited Charm Baryon Omega C Decaying to Omega 0 C Gamma written by B. Aubert and published by . This book was released on 2006 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors report the first observation of an excited singly-charmed baryon {Omega}*{sub c} (css) in the radiative decay {Omega}{sub c}{sup 0}{gamma}, where the {Omega}{sub c}{sup 0} baryon is reconstructed in the decays to the final states {Omega}{sup -}{pi}{sup +}, {Omega}{sup -} {pi}{sup +}{pi}{sup 0}, {Omega}{sup -}{pi}{sup +}{pi}{sup -}{pi}{sup +}, and {Xi}{sup -} K{sup -} {pi}{sup +}{pi}{sup +}. This analysis is performed using a dataset of 230.7 fb{sup -1} collected by the BABAR detector at the PEP-II asymmetric-energy B Factory at the Stanford Linear Accelerator Center. The mass difference between the {Omega}*{sub c} and the {Omega}{sub c}{sup 0} baryons is measured to be 70.8 {+-} 1.0(stat) {+-} 1.1(syst) MeV/c{sup 2}. They also measure the ratio of inclusive production cross sections of {Omega}*{sub c} and {Omega}{sub c}{sup 0} in e{sup +}e{sup -} annihilation.
Download or read book Energy Research Abstracts written by and published by . This book was released on 1982 with total page 1744 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings written by and published by . This book was released on 1979 with total page 678 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Weak annihilation in charm baryon decays written by I. I. Bigi and published by . This book was released on 1981 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book D Meson Production in E e Annihilation written by Petros-Afentoulis Rapidis and published by . This book was released on 1979 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Observation of the charmed baryon A 1tnc Ac in e 1hn e 1hn annihilation at 10 GeV written by and published by . This book was released on 1988 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Review of Charmed Baryons in Ee Annihilation written by and published by . This book was released on 1980 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A resonance is observed in pK−.pi., anti pK.pi.−, pK/sub S/° and anti pK/sub S/° invariant-mass spectra at 2.285 +- 0.006 GeV/c2 which is associated with the lowest-lying charmed baryon (.lambda./sub c/). The Dalitz plot and limits on other modes and on the production of other states are presented. Measurements of inclusive p and .lambda. cross sections are also presented and allow an estimate of the branching ratios B(.lambda./sub c//sup +/ .-->. pK−.pi./sup +/) = (2.2 +- 1.0)% and B(.lambda./sub c//sup +/.-->. p anti K°) = (1.1 +- 0.7)%.
Download or read book Observation of the Charmed Baryon lambda c in E e Annihilation at 10 GeV written by ARGUS Collaboration and published by . This book was released on 1988 with total page 8 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 Physics Briefs written by and published by . This book was released on 1989 with total page 1124 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Study of Double Charm and Charm Strange Baryons InElectron Positron Annihilations written by and published by . This book was released on 2007 with total page 161 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this dissertation I describe a study of double-charm and charm-strange baryons based on data collected with the BABAR Detector at the Stanford Linear Accelerator Center. In this study I search for new baryons and make precise measurements of their properties and decay modes. I seek to verify and expand upon double-charm and charm-strange baryon observations made by other experiments. The BABAR Detector is used to measure subatomic particles that are produced at the PEP-II storage rings. I analyze approximately 300 million e+e- → c{bar c} events in a search for the production of double-charm baryons. I search for the double-charm baryons?{sub cc} (containing the quarks ccd) and?{sup ++}{sub cc} (ccu) in decays to?+{sub c}K−?+ and?+{sub c}K−?+?+, respectively. No statistically significant signals for their production are found, and upper limits on their production are determined. Statistically significant signals for excited charm-strange baryons are observed with my analysis of approximately 500 million e+e- → c{bar c} events. The charged charm-strange baryons?{sub c}(2970)+,?{sub c}(3055)+,?{sub c}(3123)+ are found in decays to?+{sub c}K−?+, the same decay mode used in the?+{sub cc} search. The neutral charm-strange baryon?{sub c}(3077)° is observed in decays to?+{sub c}K?−. I also search for excited charm-strange baryon decays to?+{sub c}K8,?+{sub c}K−,?+{sub c}K8?−?+, and?+{sub c}K−?−?+. No significant charm-strange baryon signals a f h these decay modes. For each excited charm-strange baryon state that I observe, I measure its mass, natural width (lifetime), and production rate. The properties of these excited charm-strange baryons and their decay modes provide constraints for phenomenological models of quark interactions through quantum chromodynamics. My discovery of the two new charm-strange baryons?{sub c}(3055)+ and?{sub c}(3123)+ influences our theoretical understanding of charm-strange baryon states.
Download or read book Proceedings of Topical Workshop on the Production of New Particles in Super High Energy Collisions Oct 1979 University of Wisconsin Madison Dept of Physics written by Vernon Barger and published by . This book was released on 1979 with total page 706 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Observation of Exclusive B Decays to Final States Containing a Charmed Baryon written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Using data collected in the region of the[Upsilon](4S) resonance with the CLEO-II detector, they report on the first observation of exclusive decays of the B meson to final states with a charmed baryon. They have measured the branching fractions[Beta](B[sup -][yields][Lambda][sub c][sup+][bar p][pi][sup -])= (0.62[sub -0.20][sup+0.23][+-] 0.11[+-] 0.10) x 10[sup -3] and[Beta]([bar B][sup 0][yields][Lambda][sub c][sup+][bar p][pi][sup+][pi][sup -])= (1.33[sub -0.42][sup+0.46][+-] 0.31[+-] 0.21) x 10[sup -3]. In addition, they report upper limits for final states of the form[bar B][yields][Lambda][sub c][sup+][bar p](n[pi]) and[Lambda][sub c][sup+][bar p](n[pi])[pi][sup 0] where (n[pi]) denotes up to four charged pions.
