Search results for "Branch"
showing 10 items of 1278 documents
Beta-delayed particle emission of 36K
1980
Abstract 36 Ar targets of 19 μg cm 2 thickness were made by a sandwich technique in which a 70 nm layer of Al was evaporated onto the implanted Al surface between five successive implantations of 36 Ar ions. The sources of 36 K were prepared by depositing the recoil atoms from the 36 Ar(p, n) 36 K reaction by means of a helium jet onto a fast transport tape. The measured delayed particle spectra revealed 11 proton groups (0.5 MeV E p E α 36 K. Total proton and α-particle branching ratios were measured to be 4.8 × 10 −4 and 3 × 10 −5 , respectively. Partial level widths and reduced proton and α-particle transition widths were determined for several individual levels with the aid of additiona…
Observation of the electromagnetic doubly OZI-suppressed decayJ/ψ→ϕπ0
2015
Using a sample of 1.31 billion J/psi events accumulated with the BESIII detector at the BEPCII collider, we report the observation of the decay J/psi -> phi pi(0), which is the first evidence for a doubly Okubo-Zweig-Iizuka suppressed electromagnetic J/psi decay. A clear structure is observed in the K+K- mass spectrum around 1.02 GeV/c(2), which can be attributed to interference between J/psi -> phi pi(0) and J/psi -> K+K- pi(0) decays. Due to this interference, two possible solutions are found. The corresponding measured values of the branching fraction of J/psi -> phi pi(0) are [2.94 +/- 0.16(stat) +/- 0.16(syst)] x 10(-6) and [1.24 +/- 0.33(stat) +/- 0.30(syst)] x 10(-7).
Measurements ofψ(3686)→K−ΛΞ¯++c.c.andψ(3686)→γK−ΛΞ¯++c.c.
2015
Using a sample of 1.06 x 10(8) psi(3686) events produced in e(+)e(-) collisions at root s = 3.686 GeV and collected with the BESIII detector at the BEPCII collider, we present studies of the decays psi(3686) -> K-Lambda(Xi) over bar (+) + c.c. and psi(3686) -> gamma K-Lambda(Xi) over bar (+) + c.c. We observe two hyperons, Xi(1690)(-) and Xi(1820)(-), in the K-Lambda invariant mass distribution in the decay psi(3686) -> K-Lambda(Xi) over bar (+) + c.c. with significances of 4.9 sigma and 6.2 sigma, respectively. The branching fractions of psi(3686) -> K-Lambda(Xi) over bar (+) + c.c., psi(3686) -> K-Sigma(0)(Xi) over bar (+) + c.c, psi(3686) -> gamma chi cJ -> gamma K-Lambda(Xi) over bar (+…
Decay study of 246Fm at SHIP
2011
The decay chain of 246Fm has been investigated employing the SHIP separator at GSI Darmstadt. The 246Fm nuclei were produced via the 40Ar(208Pb, 2n)246Fm fusion-evaporation reaction. Improved values of the half-life, T 1/2 = 1.54(4) s, and of the spontaneous fission branching ratio, b SF = 0.068(6) , of 246Fm were obtained. The $ \beta^{+}_{}$ /electron capture branching ratio, b EC = 0.39(3) , of 242Cf was deduced. Possible structures of high-K states in 246Fm are discussed within the framework of a model calculation based on the Woods-Saxon potential.
Search for the decayB+→K¯*0(892)K+
2007
We report on a search for the process B+ -> (K) over bar*(0)(892)K+ using 232 X 10(6) Y(4S) -> B (B) over bar B decays collected with the BABAR detector at the PEP-II asymmetric-energy B factory at SLAC. From a signal yield of 25 +/- 13[stat] +/- 7[syst] B+ -> (K) over bar*(0)(892)(-> K-pi(+))K+ events, we place an upper limit on the branching fraction B(B+ -> (K) over bar*(0)(892)K+) of 1.1 X 10(-6), at the 90% confidence level.
Measurement of branching fractions in radiativeBdecays toηKγand search forBdecays toη′Kγ
2006
We present measurements of the B ->eta K gamma branching fractions and upper limits for the B ->eta K-'gamma branching fractions. For B+->eta K+gamma we also measure the time-integrated charge asymmetry. The data sample, collected with the BABAR detector at the Stanford Linear Accelerator Center, represents 232x10(6) produced B (B) over bar pairs. The results for branching fractions and upper limits at 90% confidence level in units of 10(-6) are: B(B-0 ->eta K-0 gamma)=11.3(-2.6)(+2.8)+/- 0.6, B(B+->eta K+gamma)=10.0 +/- 1.3 +/- 0.5, B(B-0 ->eta K-'(0)gamma) eta K-'(+)gamma) eta K+gamma is A(ch)=-0.09 +/- 0.12 +/- 0.01. The first errors are statistical and the second systematic.
Measurements of the branching fractions of chargedBdecays toK±π∓π±final states
2004
We present results of searches for B-meson decays to K+ pi- pi+ with the BaBar detector. With a data sample of 61.6 million BBbar pairs, we measure the branching fractions and 90% confidence-level upper limits averaged over charge-conjugate states (the first error is statistical and the second is systematic): B+ --> K*0 pi+ = (15.5 +/- 1.8 +1.5 -4.0) x 10^-6, B+ --> f0 K+, f_0 --> pi+ pi- = (9.2 +/- 1.2 +2.1 -2.6) x 10^-6, B+ --> D0bar pi+, D0bar --> K+ pi- = (184.6 +/- 3.2 +/- 9.7) x 10^-6. B+ --> rho K+ K+ pi- pi+ non-resonant < 17 x 10^-6.
Observation of the decayB¯0→Λc+p¯π0
2010
In a sample of 467 x 10(6) B (B) over bar pairs collected with the BABAR detector at the PEP- II collider at SLAC we have observed the decay (B) over bar (0) -> Lambda(+)(c)(p) over bar pi(0) and measured the branching fraction to be (1.94 +/- 0.17 +/- 0.14 +/- 0.50 x 10(-4), where the uncertainties are statistical, systematic, and the uncertainty on the Lambda(+)(c) -> pK(-)pi(+) branching fraction, respectively. We determine an upper limit of 1.5 x 10(-6) at 90% C.L. for the product branching fraction B((B) over bar (0) -> Sigma(+)(c) (2455)(p) over bar) x B(Lambda(+)(c) -> pK(-) pi(+)). Furthermore, we observe an enhancement at the threshold of the invariant mass of the baryon- antibaryo…
Dalitz plot analysis of B−→D+π−π−
2009
We report on a Dalitz plot analysis of B- -> D+pi(-)pi(-) decays, based on a sample of about 383 x 10(6) Y(4S) -> B (B) over bar decays collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. We find the total branching fraction of the three-body decay: B(B- -> D+ pi(-)pi(-)) = (1.08 +/- 0.03 +/- 0.05) x 10(-3). We observe the established D-2*(0) and confirm the existence of D-0*(0) in their decays to D+pi(-), where the D-2*(0) and D-0*(0) are the 2(+) and 0(+) c (u) over bar P-wave states, respectively. We measure the masses and widths of D-2*(0) and D-0*(0) to be: m(D2)*(0) = (2460.4 +/- 1.2 +/- 1.2 +/- 1.9) MeV/c(2), Gamma(D2*0) = (41.8 +/- 2.5 +/- 2.1 +/- 2.…
Search forB+→X(3872)K+,X(3872)→J/ψγ
2006
In a study of B+ --> J/psi gamma K+ decays, we find evidence for the radiative decay X(3872) --> J/psi gamma with a statistical significance of 3.4 sigma. We measure the product of branching fractions BF(B+ --> X(3872) K+).BF(X(3872) --> J/psi gamma) = (3.3 +/- 1.0 +/- 0.3) x 10^-6, where the uncertainties are statistical and systematic, respectively. We also measure the branching fraction BF(B+ --> chi_c1 K+) = (4.9 +/- 0.2 +/- 0.4) x 10^-4. These results are obtained from (287+/-3) million BBar decays collected at the Y(4S) resonance with the BaBar detector at the PEP-II B Factory at SLAC.