EBookClubs

Read Books & Download eBooks Full Online

EBookClubs

Read Books & Download eBooks Full Online

Book Search for a New Bottomonium State Decaying to   Upsilon 1S  pi   pi    in Pp Collisions at   sqrt s

Download or read book Search for a New Bottomonium State Decaying to Upsilon 1S pi pi in Pp Collisions at sqrt s written by and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The results of a search for the bottomonium counterpart, denoted as $X_b$, of the exotic charmonium state X(3872) is presented. The analysis is based on a sample of pp collisions at $\sqrt{s}$ = 8 TeV collected by the CMS experiment at the LHC, corresponding to an integrated luminosity of 20.7 inverse femtobarns. The search looks for the exclusive decay channel $X_b \to \Upsilon(1S) \pi^+ \pi^-$ followed by $\Upsilon(1S) \to \mu^+ \mu^-$. No evidence for an $X_b$ signal is observed. Upper limits are set at the 95% confidence level on the ratio of the inclusive production cross sections times the branching fractions to $\Upsilon(1S) \pi^+ \pi^-$ of the $X_b$ and the $\Upsilon$(2S). The upper limits on the ratio are in the range 0.9-5.4% for $X_b$ masses between 10 and 11 GeV. These are the first upper limits on the production of a possible $X_b$ at a hadron collider.

Book Observation of   Upsilon 4S  Decays To  pi  pi   Upsilon 1S   and   pi  pi   Upsilon 1S

Download or read book Observation of Upsilon 4S Decays To pi pi Upsilon 1S and pi pi Upsilon 1S 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 present the first measurement of {Upsilon}(4S) decays to {pi}{sup +}{pi}{sup -} {Upsilon}(1S) and {pi}{sup +}{pi}{sup -} {Upsilon}(2S) based on a sample of 230 x 10{sup 6} {Upsilon}(4S) mesons collected with the BABAR detector. They measure the product branching fractions {Beta}({Upsilon}(4S) {yields} {pi}{sup +}{pi}{sup -} {Upsilon}(1S)) x {Beta}({Upsilon}(1S) {yields} {mu}{sup +}{mu}{sup -}) = (2.23 {+-} 0.25{sub stat} {+-} 0.27{sub sys}) x 10{sup -6} and {Beta}({Upsilon}(4S) {yields} {pi}{sup +}{pi}{sup -}{Upsilon}(2S)) x {Beta}({Upsilon}(2S) {yields} {mu}{sup +}{mu}{sup -}) = (1.69 {+-} 0.26{sub stat} {+-} 0.20{sub sys}) x 10{sup -6}, from which they derive the partial widths {Lambda}({Upsilon}(4S) {yields} {pi}{sup +}{pi}{sup -} {Upsilon}(1S)) = (1.8 {+-} 0.4) keV and {Lambda}({Upsilon}(4S) {yields} {pi}{sup +}{pi}{sup -}{Upsilon}(2S)) = (2.7 {+-} 0.8) keV.

Book Observation of the Bottomonium Ground State in the Decay Y 3S  to Ynb

Download or read book Observation of the Bottomonium Ground State in the Decay Y 3S to Ynb 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 the results of a search for the bottomonium ground state [eta]{sub b}(1S) in the photon energy spectrum with a sample of (109 ± 1) million of [Upsilon](3S) recorded at the [Upsilon](3S) recorded at the [Upsilon](3S) energy with the BABAR detector at the PEP-II B factory at SLAC. They observe a peak in the photon energy spectrum at E{sub [gamma]} = 921.2{sub -2.8}{sup +2.1}(stat) ± 2.4(syst) MeV with a significance of 10 standard deviations. They interpret the observed peak as being due to monochromatic photons from the radiative transition [Upsilon](3S) → {gamma} [eta]{sub b}(1S). This photon energy corresponds to an [eta]{sub b}(1S) mass of 9388.9{sub -2.3}{sup +3.1}(stat) ± 2.7(syst) MeV/c2. The hyperfine [Upsilon](1S)-[eta]{sub b}(1S) mass splitting is 71.4{sub -3.1}{sup +2.3}(stat) ± 2.7(syst) MeV/c2. The branching fraction for this radiative [Upsilon](3S) decay is estimated to be (4.8 ± 0.5(stat) ± 1.2(syst)) x 10−4.

Book Observation of the Decay  tau Into Pi Upsilon

Download or read book Observation of the Decay tau Into Pi Upsilon written by PLUTO Collaboration and published by . This book was released on 1978 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Observation of the Decay  tau Becomes Rho Pi Pi Upsilon T  a  u

Download or read book Observation of the Decay tau Becomes Rho Pi Pi Upsilon T a u written by ARGUS Collaboration and published by . This book was released on 1990 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Search for Radiative Decays of Upsilon 1S  Into Eta and Eta prime

Download or read book Search for Radiative Decays of Upsilon 1S Into Eta and Eta prime written by Vijay Singh Potlia and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: We conducted a new search for the radiative decay of Upsilon(1S) to the pseudoscalar mesons eta and eta-prime in (21.2"0.2) x 106 Upsilon(1S) decays collected with the CLEO III detector operation at the Cornell Electron Strorage Ring (CESR). The eta meson was reconstructed in the three modes eta to gamma gamma, eta to pipi−pi0 or eta to pi0 pi0 pi0. The eta-prime meson was reconstructed in the mode eta-prime to pi pi− eta with eta decaying through any of the above three modes; and also eta-prime to gamma rho0, where rho0 to pi+ pi−-. The first six of these decay chains were searched for in the previous CLEO II analysis on this subject, which used a data sample 14.6 times smaller. Five of the seven submodes were virtually background free. We found no signal events in four of them. The only exception was Upsilon(1S) to gamma eta-prime; eta to pi+ pi− pi0 where we observed two good signal candidates. The other two submodes (eta to gamma gamma and eta-prime to gamma rho) are background limited, and showed no excess of events in the signal region. We combined the results from different channels and obtained 90% confidence level (C.L.) upper limits branching fraction(Upsilon(1S) to gamma eta)

Book Measurement of the Decay UPSILON 2S        Pi      Pi    UPSILON 1S

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).

Book Measurement of the Decay  Upsilon  S2   approaches   Pi Pi Upsilon  1S

Download or read book Measurement of the Decay Upsilon S2 approaches Pi Pi Upsilon 1S written by CRYSTAL BALL Collaboration and published by . This book was released on 1985 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Observation of the Bottomonium Ground State  Eta b  at BaBar

Download or read book Observation of the Bottomonium Ground State Eta b at BaBar written by and published by . This book was released on 2008 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors present the first observation of the bottomonium ground state [eta]{sub b}(1S) in the photon energy spectrum using a sample of (109 ± 1) million of [Upsilon](3S) events recorded at the [Upsilon](3S) energy with the BaBar detector at the PEP-II B factory at SLAC. A peak at E{sub [gamma]} = 921.2{sub -2.8}{sup +2.1}(stat) ± 2.4(syst) MeV observed with a significance of 10 standard deviations in the photon energy spectrum is interpreted as being due to the radiative transition [Upsilon](3S) → {gamma} [eta]{sub b}(1S). This photon energy corresponds to an [eta]{sub b}(1S) mass of 9388.9{sub -2.3}{sup +3.1}(stat) ± 2.7(syst) MeV/c2. The hyperfine [Upsilon](1S)-[eta]{sub b}(1S) mass splitting is 71.4{sub -3.1}{sup +2.3}(stat) ± 2.7(syst) MeV/c2. The branching fraction for this radiative [Upsilon](3S) decay is obtained as (4.8 ± 0.5(stat) ± 1.2(syst)) x 10−4.

Book Measurement of the Decay  Upsilon  2S       pi 0 pi 0 Upsilon  1S

Download or read book Measurement of the Decay Upsilon 2S pi 0 pi 0 Upsilon 1S written by David Michael Gelphman and published by . This book was released on 1985 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Study of Hadronic Transitions Between  Upsilon States and Observation of  Upsilon 4S  To eta Upsilon 1S  Decay

Download or read book Study of Hadronic Transitions Between Upsilon States and Observation of Upsilon 4S To eta Upsilon 1S Decay written by and published by . This book was released on 2008 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors present a study of hadronic transitions between [Upsilon](mS) (m = 4,3,2) and [Upsilon](nS) (n = 2,1) resonances based on 347.5 fb−1 of data taken with the BABAR detector at the PEP-II storage rings.

Book Observation of the Decays B  to Ds     K  Pi

Download or read book Observation of the Decays B to Ds K Pi written by B. Aubert and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors report first observations of the decays B{sup -} {yields} D{sub s}{sup (*)+} K{sup -}{pi}{sup -}, using 292 fb{sup -1} of data collected at the {Upsilon}(4S) resonance energy by the BABAR detector at the PEP-II e{sup +}e{sup -} collider. The branching fractions are measured to be {Beta}(B{sup -} {yields} D{sub s}{sup +}K{sup -}{pi}{sup -}) = (1.88 {+-} 0.13 {+-} 0.41) {center_dot} 10{sup -4} and {Beta}(B{sup -} {yields} D{sub s}{sup *+}K{sup -}{pi}{sup -}) = (1.84 {+-} 0.19 {+-} 0.40) {center_dot} 10{sup -4}.