Measurements of decay branching fractions of H→b■/c■/gg in associated (e^+e^-/μ^+μ^-)H production at the CEPC

The high-precision measurement of Higgs boson properties is one of the primary goals of the Circular Electron Positron Collider(CEPC).The measurements ofH→bb/cc/gg decay branching fraction in the CEPC experiment is presented,considering a scenario of analysing 5000 fb-1 e^+e^-collision data with the center-of-mass energy of 250 Ge V.In this study the Higgs bosons are produced in association with a pair of leptons,dominantly mediated by the ZH production process.The statistical uncertainty of the signal cross section is estimated to be about 1%in theH→bb final state,and approximately 5%-10%in theH→cc/gg final states.In addition,the main sources of the systematic uncertainties and their impacts to the measurements of branching fractions are discussed.This study demonstrates the potential of precise measurement of the hadronic final states of the Higgs boson decay at the CEPC,and will provide key information to understand the Yukawa couplings between the Higgs boson and quarks,which are predicted to be the origin of quarks’masses in the standard model.

An Explanation for the Violation of Lepton Universality in Beauty-Quark Decays: The Binary Isotope Mixture of Beauty-Quarks

This paper purposes an explanation for the recent evidence for the violation of lepton universality in beauty-quark decays at CERN’s Large Hadron Collider. A beauty meson (B+) transforms into a strange meson (K+) with the emission of either electron-positron (e+e-) or muon-antimuon (μ+μ-). The ratio (RK) of branching fractions for B+ → K+μ+μ- and B+→ K+e+e- decays is measured to be RK = 0.846 instead of 1 in the violation of lepton universality in the Standard Model. This paper proposes that the violation is derived from the binary isotope mixture of two beauty-quarks, b7 (4979 MeV mass) and b8 (143,258 MeV mass) whose masses are calculated from the periodic table of elementary particles. b7 is the observable B, while b8 is the hidden B to preserve the generation number symmetry between the three lepton family generations and the three quark family generations in the Standard Model. The preservation of the generation number symmetry forbids b8 to decay into K+μ+μ-. In the transition state involving the virtual particles (γ, W± and Z°) before the decay, b7 and b8 emerge to form the binary isotope mixture from B. The rates of emergence as the rates of diffuse in Graham’s law of diffusion are proportional to inverse square root of mass. The rate ratio between b8/b7 is (4979/143,258)1/2 = 0.1864. Since b7 decays into K+, e+e-, and μ+μ-, while b8 decays into K+, e+e-, and forbidden μ+μ-, the calculated ratio (RK) of branching fractions for B+→ K+μ+μ- and B+→ K+e+e- is 0.5/(0.1864 × 0.5+ 0.5) = 0.843 in excellent agreement with the observed 0.846. The agreement between the calculated RK and the observed RK confirms the validity of the periodic table of elementary particles which provides the answers for the dominance of matter over antimatter, dark-matter, and the mass hierarchy of elementary particles.

Three-Dimensional Generalized Inverse Matrix Rational Interpolation

In this paper, a three dimensional matrix valued rational interpolant (TGMRI) is first constructed by making use of the generalized inverse of matrices. The interpolants are of the Thiele type branched continued fraction form, with matrix numerator and scalar denominator. Some properties of TGMRI are given. An efficient recursive algorithm is proposed. The results in the paper can be extend to n variable.

Study of the production of Λ_b^0 band ~0 hadrons in pp collisions and first measurement of the Λ_b^0→J/ψpK^- branching fraction

The product of the ∧0/b （-B/0） differential production cross-section and the branching fraction of the decay ∧0/b→ J/ψ pK-（-B/0→ J/ψ-K＊（892）0）is measured as a function of the beauty hadron transverse momentum, PT, and rapidity, y. The kinematic region of the measurements is pT〈20 GeV/c and 2.0 〈g〈4.5.The measurements use a data sample corresponding to an integrated luminosity of 3fb-1 collected by the LHCb detector in pp collisions at centre-of-mass energies √s=7 TeV in 2011 and √s=8 TeV in 2012. Based on previous LHCb results of the fragmentation fraction ratio,f∧0/b/fd,the branching fraction of the decay ∧0/b→ J/ψ pK-is measured to be B（∧0/b→ J/ψ pK-）=（3.17±0.04±0.07±0.34＋0.45/-0.28）×10-4,where the first uncertainty is statistical, the second is systematic, the third is due to the uncertainty on the branching fraction of the decay -B/0 →J/ψ-K＊（892）0,and the fourth is due to the knowledge of f∧0/b/fd.The sum of the asymmetries in the production and decay between ∧0/b and ∧0/bis also measured as a function of PT and y.The previously published branching fraction of ∧0/b→ J/ψ pπ-,relative to that of ∧0/b→ J/ψ pK-,is updated. The branching fractions of ∧0/b→P＋c（→ J/ψp）K-are determined.

Measurement of the absolute branching fraction of D^+→K^0e^+v_e via K^0→π~0π~0

By analyzing 2.93 fb-1 data collected at the center-of-mass energy v/S = 3.773 GeV with the BESIII detector, we measure the absolute branching fraction of the semileptonic decay D＋- k0e＋ ve via k0-π0π0 - （8.59 ± 0.14 ± 0.21）% using k0- k0-π0π0, where the first uncertainty is statistical and the second systematic. Our result is consistent with previous measurements within uncertainties..

baryonic decays branching fraction alpha distribution

The decay ψ（2S）→Ω-Ω＋ is analyzed using 14×106 ψ（2S） events recorded by the Beijing Spectrometer Ⅱ （BESⅡ） at the Beijing Electron Positron Collider （BEPC）. Based upon events with no missing charged tracks and a satisfactory four-constraint kinematic t, we determine the upper limit for the branching fraction of ψ（2S）→Ω-Ω＋ to be 1.5×104 at a 90% confidence level. By including events with one missing charged track, we are able to report the first evidence of an Ω＋ signal with a statistical signi cance of 3.1｜σ. The branching fraction of ψ（2S）Ω＋ is determined to be （4.80±1.56（stat）±1.30（sys））105.

Λ_(c)^(+)→Λh^(+)和Λc+→∑^(0)h^(+)(h=K,π)衰变道CP破坏的寻找和其分支比与衰变不对称参数的测量

本文报告了粲重子Λ_(c)^(+)的四个弱衰变道Λ_(c)^(+)→Λh^(+)和Λ_(c)^(+)→∑^(0)h^(+)(h=K,π)的系列研究.基于在KEKB能量不对称的正负电子对撞机上的Belle探测器收集的980 fb-1数据样本,作者测量了粲重子两体单卡比玻压低(SCS)衰变过程中的直接电荷共轭-宇称(CP)不对称:ACPdir(Λ_(c)^(+)→ΛK^(+))=+0.021±0.026±0.001和ACPdir(Λ_(c)^(+)→∑^(0)K^(+))=+0.025±0.054±0.004;精确测量了衰变不对称参数(α)和其引起的CP不对称度:AC^(α)_(P)(Λ_(c)^(+)→ΛK^(+))=-0.023±0.086±0.071和AC^(α)_(P)(Λ_(c)^(+)→∑^(0)K^(+))=+0.08±0.035±0.14.这是粲重子SCS衰变的第一个AC^(α)_(P)结果;其次,作者在实验上利用粲重子衰变来寻找超子CP破坏,即利用Λ_(c)^(+)→(Λ,∑^(0))π^(+)衰变获得AC^(α)_(P)(Λ→pπ-)=+0.013±0.007±0.011.以上测量均未发现重子CP破坏的证据.此外,该文还报告了Λ_(c)^(+)两个SCS衰变道的分支比测量:B(Λ_(c)^(+)-ΛK^(+))=(6.57±0.17±0.11±0.35)×10^(-4)和B(Λ_(c)^(+)→∑^(0)K^(+))=(3.58±0.19±0.06±0.19)×10^(-4),这些均为目前最精确的结果.

Search for the rare decays W^(+)→D_(s)^(+)γ and Z→D^(0)γ at LHCb

A search for the rare decays W^(+)→D_(s)^(+)γ and Z→D0γis performed using proton-proton collision data collected by the LHCb experiment at a centre-of-mass energy of 13TeV,corresponding to an integrated luminosity of 2.0fb−1.No significant signal is observed for either decay mode and upper limits on their branching fractions are set using W^(+)→D_(s)^(+)γ and Z→μ+μ−decays as normalization channels.The upper limits are 6.5×10^(−4) and 2.1×10^(−3) at 95% confidence level for the W^(+)→D_(s)^(+)γ and Z→D^(0)γ decay modes,respectively.This is the first reported search for the Z→D^(0)γ decay,while the upper limit on the W+→D+sγbranching fraction improves upon the previous best limit.

Observations of the Cabibbo-Suppressed decays Λ_(c)^(+)→nπ+π^(0),nπ^(+)π^(-)π^(+) and the Cabibbo-Favored decay Λ_(c)^(+)→nK^(-)π^(+)π^(+)

Using electron-positron annihilation data samples corresponding to an integrated luminosity of 4.5 fb-1,collected by the BESⅢdetector in the energy region between 4599.53 MeV and 4698.82 MeV,we report the first observations of the Cabibbo-suppressed decaysΛ_(c)^(+)→nπ^(+)π^(0),Λ_(c)^(+)→nπ^(+)π^(-)π^(+),and the Cabibbo-favored decayΛ_(c)^(+)→nK^(-)π^(+)π^(+)with statistical significances of 7.9σ,7.8σ,and>10σ,respectively.The branching fractions of these decays are measured to be B(Λ_(c)^(+)→nπ^(+)π^(0))=(0.64±0.09±0.02)%,B(Λ_(c)^(+)→nπ^(+)π^(-)π^(+))=(0.45±0.07±0.03)%,and B(Λ_(c)^(+)→nK^(-)π^(+)π^(+))=(1.90±0.08±0.09)%,where the first uncertainties are statistical and the second are systematic.We find that the branching fraction of the decayΛ_(c)^(+)→nπ^(+)π^(0)is about one order of magnitude higher than that ofΛ_(c)^(+)→nπ^(+).

τ lepton decay

We discuss recent results on τ lepton physics obtained at the BABAR, Belle and KEDR detectors They include tests of lepton universality using new measurements of T lepton mass and some branching fractions Also described are selected results on τ lepton hadronic decays coming from BABAR and Belle.

BIVARIATE RATIONAL IN TERPOLANTS WITHRECTANGLE-HOLE-STRUCTURE

Bivariate vector valued rational interpolants are established by means of Thiele-type branched continued fractions and Samelson inverse over rectangular grids with holes, characterisation theorem with topologic structure is brought in light and uniqueness theorem in some sense is obtained.

Discovery potentials of doubly charmed baryons

The existence of doubly heavy flavor baryons has not been well established experimentally so far. In this Letter we systematically investigate the weak decays of the doubly charmed baryons, Ξ;and Ξ;, which should be helpful for experimental searches for these particles. The long-distance contributions are first studied in the doubly heavy baryon decays, and found to be significantly enhanced. Comparing all the processes, Ξ;→Λ;K;π;π;andΞ;π;are the most favorable decay modes for experiments to search for doubly heavy baryons.

Search for new physics in the B→K^((*))l^+l^- decays at BABAR

Based on a data sample of 384 million BB pairs collected with the BABAR detector at the PEP-Ⅱ asymmetric e ＋ e ￣ storage ring,we measure branching fractions,direct CP,isospin and lepton-flavor asymmetries for the rare decays B → K （＊） l ＋ l￣ in two di-lepton mass bins above and below the J/ψ resonance.For the B → K＊ l ＋ l￣ decay,we also measure the K＊ longitudinal polarization fraction and the di-lepton forwardbackward asymmetry.

Search for the rare decay B^(0)→J/ψФ

A search for the rare decay B^(0)→J/ψФis performed using Pp collision data collected with the LHCb dete-ctor at centre-of-mass energies of 7,8 and 13 TeV,corresponding to an integrated luminosity of9 fb.No significant signal of the decay is observed and an upper limitof 1.1x 10^(-7)at 90%confidence level is set on the branching fraction.

Pseudoscalar mixing in J/ψ and ψ(2S) decay

Based on the branching fractions of J/ψ（ψ（2S））→ VP from different collaborations, pseudoscalar mixing is extensively discussed with a well established phenomenological model. The mixing angle is determined to be -14° by fitting to the new world average if only quark content is considered. After taking into account the gluonic content in η and η＇ simultaneously, the investigation shows that η favors only consisting of light quarks, while the gluonic content of η＇ is Z2η＇, = 0.30±0.24.

Weak decays of doubly heavy baryons:B_(cc)→BD^(*)

The discovery of Ξ_(cc)^(++)has inspired new interest in studying doubly heavy baryons.In this study,the weak decays of a doubly charmed baryon B_(cc)to a light baryon B and a charm meson D^(*)(either a pseudoscalar or a vector one)are calculated.Following our previous work,we calculate the short distance contributions under the factorization hypothesis,whereas the long distance contributions are modeled as the final state interactions,which are calculated with the one particle exchange model.We find that the B_(cc)→BD^(*)decays'branching ratios are obviously larger,as they receive contributions of more polarization states.Among the decays that we investigate,the following have the largest branching fractions:BR(Ξ_(cc)^(++)→∑^(+)D^(*+))∈[0.46%,3.33%]estimated with τΞ_(cc)^(++)=256 fs;BR(Ξ_(cc)^(+)→AD^(*+))∈[0.38%,2.63%]and BR(Ξ_(cc)^(+)→∑^(0)D^(*+))∈[0.45%,3.16%]with τΞ_(cc)^(++)=45 fs;and BR(Ω_(cc)^(+)→Ξ^(0)D^(+))∈[0.27%,1.03%),BR(Ω_(cc)^(+)→∑^(0)D^(*+))∈[0.07%,0.44%],and BR(Ω_(cc)^(+)→∑^(0)D^(*+))∈[0.06%,0.45%] with τ_(Ω_(cc))^(+)=75 fs.By comparing the decay widths of pure color commensurate channels with those of pure bow-tie ones we find that the bow-tie mechanism plays an important role in charm decays.

Search for ψ(4S) → ηJ/ψ in B~±→ ηJ/ψK~± and e^+e^-→ ηJ/ψ processes

We search for the ψ（4S）state in the B±→ηJ/ψK± and e＋e-→η/Jψ processes based on the Belle measurements with the assumed mass M =（4230±8）MeV/C2 and width Г=（38±12）MeV. No significant signal is observed in the in mass spectra. The 90% confidence level upper limit on the product branching fraction B（B±→（4S）→e＋e-to be 0.63 keV,a branching fraction limit B（ψ（4S）→ηJ/ψ）〈1.3% is obtained at the 90% confidence level in e＋e-→η/Jψ,which is consistent with the theoretical prediction.

Measurement of J/ψ decays into Λ■ π^+π^-

Based on 58 million J/ψ events collected by the BESⅡ detector at the BEPC, J/ψ→ΛΛ π＋π- is observed for the first time. The branching fraction is measured to be Br（J/ψ→ΛΛ π＋π-）=（4.30±0.13±0.99）×10-3, excluding the decays to intermediate states, namely J/ψ→Ξ-Ξ＋, J/ψ→Σ（1385）-Σ（1385）＋, and J/ψ→Σ（1385）＋Σ（1385）-. The branching fractions for these intermediate resonance channels are measured to be：Br（J/ψ→Ξ-Ξ＋）=（0.90±0.03±0.18）×10-3, Br（J/ψ→Σ（1385）-Σ（1385）＋）=（1.23±0.07±0.30）×10-3,and Br（J/ψ→Σ（1385）＋Σ（1385）-）=（1.50±0.08±0.38）×10-3, respectively. The angular distribution is of the form dN/d（cosθ）α（1＋αcos2θ） with α=（0.35±0.29±0.06） for J/ψ→Ξ-Ξ＋, α=（-0.54±0.22±0.10） for J/ψ→Σ（1385）-Σ（1385）＋, and α=（-0.35±0.29±0.06） for J/ψ→Σ（1385）＋Σ（1385）-.