107,252 research outputs found
INCLUSIVE CHI-C AND B-QUARK PRODUCTION IN (P)OVER-BAR-P COLLISIONS AT ROOT-S = 1.8 TEV
No full textWe report the full reconstruction of chi(c) mesons through the decay chain chi(c) --> J/psigamma, J/psi --> mu+mu-, using data obtained at the Collider Detector at Fermilab in 2.6 +/- 0.2 pb-1 of ppBAR collisions at square-root s = 1.8 TeV. This exclusive chi(c) sample is used to measure the chi(c)-meson production cross section times branching fractions. We obtain sigma x B = 3.2 +/- 0.4(stat)-1.1(+1.2)(syst) nb for chi(c) mesons decaying to J/psi with p(T) > 6.0 GeV/c and pseudorapidity Absolute value of eta 8.5 GeV/c and \y(b)\ < 1
Measurement of sigma B-chi c2(chi(c2)-> J/psi gamma)/sigma B-chi c1(chi(c1)-> J/psi gamma) in p(p)over-bar collisions at root s=1.96 TeV
Full text linkWe measure the ratio of cross section times branching fraction, R-p=sigma B-chi c2(chi(c2)-> J/psi gamma)/sigma B-chi c1(chi(c1)-> J/psi gamma), in 1.1 fb(-1) of p (p) over bar collisions at root s=1.96 TeV. This measurement covers the kinematic range p(T)(J/psi)> 4.0 GeV/c, |eta(J/psi) 1.0 GeV/c. For events due to prompt processes, we find R-p=0.395 +/- 0.016(stat)+/- 0.015(syst). This result represents a significant improvement in precision over previous measurements of prompt chi(c1,2) hadro production
Production of chi(c1) and chi(c2) in p(p)over-bar collisions at root s=1.8 TeV
No full textWe have measured the ratio of prompt production rates of the charmonium states chi(c1) and chi(c2) in 110 pb(-1) of pp collisions at sqrt[s] = 1.8 TeV. The photon from their decay into J/psi(gamma) is reconstructed through conversion into e+e- pairs. The energy resolution this technique provides makes the resolution of the two states possible. We find the ratio of production cross sections sigma(chi(c2))/sigma(chi(c1)) = 0.96+/-0.27(stat)+/-0.11(syst) for events with pT(J/psi) > 4.0 GeV/c, /eta(J/psi)/ 1.0 GeV/c
Observation of chi(cJ) -> 4K(S)(0)
No full textKolcu, Onur Buğra (Arel Author)By analyzing (448.1 +/- 2.9) x 10(6) psi(3686) events collected with the BESIII detector operating at the BEPCII collider, the decays of chi(c)(J) -> 4K(S)(0) (J = 0, 1, 2) are observed for the first time with statistical significances of 26.5 sigma, 5.9 sigma and 11.4 sigma, respectively. The product branching fractions of psi(3686) -> gamma chi(cJ), chi(cJ) -> 4K(S)(0 )are presented, and the branching fractions of chi(cJ) -> 4K(S)(0) decays are determined to be B-chi c0 -> 4KS0 = (5.76 +/- 0.34 +/- 0.38) x 10(-4), B-chi c1 -> 4KS0 = (0.35 +/- 0.09 +/- 0.03) x 10(-4) and B-chi c2 -> 4KS0( )= (1.14 +/- 0.15 +/- 0.08) x 10(-4), where the first uncertainties are statistical and the second are systematic, respectively
Maximally selected chi-square statistics and umbrella orderings
Full text linkBinary outcomes that depend on an ordinal predictor in a non-monotonic way are common in medical data analysis. Such patterns can be addressed in terms of cutpoints: for example, one looks for two cutpoints that define an interval in the range of the ordinal predictor for which the probability of a positive outcome is particularly high (or low). A chi-square test may then be performed to compare the proportions of positive outcomes in and outside this interval. However, if the two cutpoints are chosen to maximize the chi-square statistic, referring the obtained chi-square statistic to the standard chi-square distribution is an inappropriate approach. It is then necessary to correct the p-value for multiple comparisons by considering the distribution of the maximally selected chi-square statistic instead of the nominal chi-square distribution. Here, we derive the exact distribution of the chi-square statistic obtained by the optimal two cutpoints. We suggest a combinatorial computation method and illustrate our approach by a simulation study and an application to varicella data
As the Lightest State
No full textThe state has recently been demoted by the Particle Data Group from its previous status as the conventional state, largely due to the absence of expected decays. We propose that is actually the lightest state, and calculate the spectrum of such states using the diquark model, identifying many of the observed charmoniumlike states that lack open-charm decay modes as . Among other results, we argue that is a state that has been not been seen in two-photon fusion largely as a consequence of the Landau-Yang theorem.The state χc0(3915) has recently been demoted by the Particle Data Group from its previous status as the conventional cc¯ 23P0 state, largely due to the absence of expected DD¯ decays. We propose that χc0(3915) is actually the lightest cc¯ss¯ state, and calculate the spectrum of such states using the diquark model, identifying many of the observed charmoniumlike states that lack open-charm decay modes as cc¯ss¯. Among other results, we argue that Y(4140) is a JPC=1++ cc¯ss¯ state that has been not been seen in two-photon fusion largely as a consequence of the Landau-Yang theorem.The state has recently been demoted by the Particle Data Group from its previous status as the conventional state, largely due to the absence of expected decays. We propose that is actually the lightest state, and calculate the spectrum of such states using the diquark model, identifying many of the observed charmoniumlike states that lack open-charm decay modes as . Among other results, we argue that is a state that has been not been seen in two-photon fusion largely as a consequence of the Landau-Yang theorem
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Inclusive {chi}{sub c} production in {bar p}p collisions at {radical}s = 1.8 TeV
No full textWe report the full reconstruction of X, mesons through the decay chain {chi}{sub c} {yields} J/{psi}{gamma}, J/{psi} {yields} {mu}{sup +}{mu}{sup {minus}}, using data obtained at the Collider Detector at Fermilab in {bar p}p collisions at {radical}s = 1.8 TeV. This sample, the first observed at a hadron collider, is then used to measure the {chi}{sub s} meson production cross section times branching fractions. We obtain {sigma} {center_dot} Br = 3.2 {plus_minus} 0.4(stat) {plus_minus} 1.1(syst) nb for {chi}{sub s}, mesons with P{sub T} > T.0 GeV/c{sup 2} and pseudorapidity {vert_bar}{eta}{vert_bar} < 0.5. From this and the inclusive J/ {psi} cross section we calculate the inclusive b-quark crow section
Wen-Chi Chang Oboe Recital Program Notes
No full textThe essay is the program notes of Wen-Chi Chang`s Oboe Recital which was performed on May 9th, 2019. The recital includes four different periods of oboe repertoire, baroque period, classical music period, romantic music period, and modern music period. The recital opened with Antonio Lucio Vivaldi: Oboe Concerto in D Major, RV. 453, Vivaldi was the most important Italian composer and violinist in the Baroque period. His numerous works are in a great astonishment which are including various genres. The second peice is Domenico Cimarosa: Oboe Concerto in C Major, Cimarosa is the most famous Italian opera composer in the 18th century. His opera works are mainly comedy.
\ue3\ue3 The second half of the recital was opened with Charles Camille Saint-Sa\uc3\uabns: Sonata for oboe and Piano, Op. 166, Saint-Sa\uc3\uabns was a French composer, keyboardist and music educator. He has created many important musical works and has a profound influence on future generations. And ended was Paul Hindemith: Sonata for Oboe and Piano, Hindemith was the most representative German composer in the early twentieth century, and an outstanding music performer and music educator. In this program notes article, I will use these four musical works as the topic to overview the life of the four composers, the background of the music composition and the interpretation of each works
Psychosocial Adjustment along the Posttraumatic Flow in Adult Survivors of the Taiwan 1999 Chi-Chi Earthquake: A Four-Year Longitudinal Study
No full textMeasurement of the ratio of prompt χ c to J / ψ production in pp collisions at √s = 7 TeV
Full text linkThe prompt production of charmonium χ c and J / ψ states is studied in proton-proton collisions at a centre-of-mass energy of √s = 7 TeV at the Large Hadron Collider. The χ c and J / ψ mesons are identified through their decays χ c → J / ψ γ and J / ψ → μ + μ - using 36 pb - 1 of data collected by the LHCb detector in 2010. The ratio of the prompt production cross-sections for χ c and J / ψ, σ (χ c → J / ψ γ) / σ (J / ψ), is determined as a function of the J / ψ transverse momentum in the range 2 < p T J / ψ < 15 GeV / c. The results are in excellent agreement with next-to-leading order non-relativistic expectations and show a significant discrepancy compared with the colour singlet model prediction at leading order, especially in the low p T J / ψ region
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