2621524
Study of the mass and spin-parity of the Higgs boson candidate via its decays to Z boson pairs.
A study is presented of the mass and spin-parity of the new boson recently observed at the LHC at a mass near 125 GeV. An integrated luminosity of 17.3 fb(-1), collected by the CMS experiment in proton-proton collisions at center-of-mass energies of 7 and 8 TeV, is used. The measured mass in the ZZ channel, where both Z bosons decay to e or μ pairs, is 126.2 ± 0.6(stat) ± 0.2(syst) GeV. The angular distributions of the lepton pairs in this channel are sensitive to the spin-parity of the boson. Under the assumption of spin 0, the present data are consistent with the pure scalar hypothesis, while disfavoring the pure pseudoscalar hypothesis.
116971112
Search for B0 Meson Decays to pi0 K0(S) K0(S), eta K0(S) K0(S), and eta-prime K0(S) K0(S)
We describe searches for B-0 meson decays to the charmless final states pi(KSKS0)-K-0-K-0, eta(KSKS0)-K-0, and eta(KSKS0)-K-'-K-0. The data sample corresponds to 467x10(6) BB pairs produced in e(+)e(-) annihilation and collected with the BABAR detector at the SLAC National Accelerator Laboratory. We find no significant signals and determine the 90% confidence level upper limits on the branching fractions, in units of 10(-7), B(B-0 ->pi(KSKS0)-K-0-K-0) eta(KSKS0)-K-0) eta(KSKS0)-K-'-K-0)< 20.
122803232
Search for Microscopic Black Hole Signatures at the Large Hadron Collider
A search for microscopic black hole production and decay in pp collisions at a center-of-mass energy of 7 TeV has been conducted by the CMS Collaboration at the LHC, using a data sample corresponding to an integrated luminosity of 35 inverse picobarns. Events with large total transverse energy are analyzed for the presence of multiple high-energy jets, leptons, and photons, typical of a signal expected from a microscopic black hole. Good agreement with the expected standard model backgrounds, dominated by QCD multijet production, is observed for various final-state multiplicities. Limits on the minimum black hole mass are set, in the range 3.5 -- 4.5 TeV, for a variety of parameters in a model with large extra dimensions, along with model-independent limits on new physics in these final states. These are the first direct limits on black hole production at a particle accelerator.
10609473
Precise measurement of the e+e- --> pi+pi-(gamma) cross section with the initial state radiation method at BABAR.
A precise measurement of the cross section of the process e(+)e(-) --> pi(+)pi(-)(gamma) from threshold to an energy of 3 GeV is obtained with the initial state radiation (ISR) method using 232 fb(-1) of data collected with the BABAR detector at e(+)e(-) center-of-mass energies near 10.6 GeV. The ISR luminosity is determined from a study of the leptonic process e(+)e(-) --> mu(+)mu(-)gamma(gamma). The leading-order hadronic contribution to the muon magnetic anomaly calculated using the pipi cross section measured from threshold to 1.8 GeV is (514.1 +/- 2.2(stat) +/- 3.1(syst)) x 10(-10).
110632418
The BABAR detector: Upgrades, operation and performance
The BaBar detector operated successfully at the PEP-II asymmetric e +e- collider at the SLAC National Accelerator Laboratory from 1999 to 2008. This report covers upgrades, operation, and performance of the collider and the detector systems, as well as the trigger, online and offline computing, and aspects of event reconstruction since the beginning of data taking.
10401636
Search for di-muon decays of a low-mass Higgs boson in radiative decays of the Υ(1S)
We search for di-muon decays of a low-mass Higgs boson (A^0) produced in radiative Υ(1S) decays. The Υ(1S) sample is selected by tagging the pion pair in the Υ(2S,3S) → π^+ π^-Υ(1S) transitions, using a data sample of 92.8 × 10^6 Υ(2S) and 116.8 × 10^6 Υ(3S) events collected by the BABAR detector. We find no evidence for A^0 production and set 90% confidence level upper limits on the product branching fraction B(Υ(1S) → γA^0) × B(A^0 → μ^ +μ^-) in the range of (0.28-9.7) × 10^(-6) for 0.212 ≤ m_A^0 ≤ 9.20  GeV/c^2. The results are combined with our previous measurements of Υ(2S,3S) → γA^0, A^0 → μ^+μ^- to set limits on the effective coupling of the b quark to the A^0.
53364111
Proton-air cross section measurement with the ARGO-YBJ cosmic ray experiment
The proton-air cross section in the energy range 1-100 TeV has been measured by the ARGO-YBJ cosmic ray experiment. The analysis is based on the primary cosmic ray flux attenuation for different atmospheric depths (i.e. zenith angles) and exploits the detector capabilities of selecting the shower development stage by means of hit multiplicity, density and lateral profile measurements at ground. The effects of shower fluctuations, the contribution of heavier primaries and the uncertainties of the hadronic interaction models, have been taken into account. The results have been used to estimate the total proton-proton cross section at center-of-mass energies between 70 and 500 GeV, where no accelerator data are currently available.
52266731
Measurement of the cosmic ray antiproton/proton flux ratio at TeV energies with the ARGO-YBJ detector
B. Bartoli, 2 P. Bernardini, 4 X.J. Bi, C. Bleve, 4 I. Bolognino, 7 P. Branchini, A. Budano, A.K. Calabrese Melcarne, P. Camarri, 11 Z. Cao, R. Cardarelli, S. Catalanotti, 2 C. Cattaneo, S.Z. Chen, T.L. Chen, Y. Chen, P. Creti, S.W. Cui, B.Z. Dai, G. D’Aĺı Staiti, 16 Danzengluobu, I. De Mitri, 4 B. D’Ettorre Piazzoli, 2 T. Di Girolamo, 2 X.H. Ding, G. Di Sciascio, ∗ C.F. Feng, Zhaoyang Feng, Zhenyong Feng, E. Giroletti, 7 Q.B. Gou, Y.Q. Guo, H.H. He, Haibing Hu, Hongbo Hu, Q. Huang, M. Iacovacci, 2 R. Iuppa, 11, † I. James, 19 H.Y. Jia, Labaciren, H.J. Li, J.Y. Li, X.X. Li, G. Liguori, 7 C. Liu, C.Q. Liu, J. Liu, M.Y. Liu, H. Lu, X.H. Ma, G. Mancarella, 4 S.M. Mari, 19 G. Marsella, 20 D. Martello, 4 S. Mastroianni, P. Montini, 19 C.C. Ning, A. Pagliaro, M. Panareo, B. Panico, 11 L. Perrone, P. Pistilli, 19 X.B. Qu, F. Ruggieri, P. Salvini, R. Santonico, 11 P.R. Shen, X.D. Sheng, F. Shi, C. Stanescu, A. Surdo, Y.H. Tan, P. Vallania, 23 S. Vernetto, 23 C. Vigorito, 24 B. Wang, H. Wang, C.Y. Wu, H.R. Wu, B. Xu, L. Xue, Y.X. Yan, Q.Y. Yang, X.C. Yang, Z.G. Yao, A.F. Yuan, M. Zha, H.M. Zhang, Jilong Zhang, Jianli Zhang, L. Zhang, P. Zhang, X.Y. Zhang, Y. Zhang, Zhaxiciren, Zhaxisangzhu, X.X. Zhou, F.R. Zhu, Q.Q. Zhu, and G. Zizzi
52995463
OBSERVATION OF TeV GAMMA RAYS FROM THE CYGNUS REGION WITH THE ARGO-YBJ EXPERIMENT
We report the observation of TeV γ-rays from the Cygnus region using the ARGO-YBJ data collected from 2007 November to 2011 August. Several TeV sources are located in this region including the two bright extended MGRO J2019+37 and MGRO J2031+41. According to the Milagro data set, at 20 TeV MGRO J2019+37 is the most significant source apart from the Crab Nebula. No signal from MGRO J2019+37 is detected by the ARGO-YBJ experiment, and the derived flux upper limits at the 90% confidence level for all the events above 600 GeV with medium energy of 3 TeV are lower than the Milagro flux, implying that the source might be variable and hard to be identified as a pulsar wind nebula. The only statistically significant (6.4 standard deviations) γ-ray signal is found from MGRO J2031+41, with a flux consistent with the measurement by Milagro.
122785773
XYZ physics at BESIII
In this talk, we present the recent study on the charmonium-like states from the BESIII Collaboration based on large data samples above D ¯ D threshold. The observation of X(3872) from the Y(4260) radiative transition, the study of the Y states from the e + e − → π + π − hc process, and the observation of the charged Zc states are included .
125260045
Evidence of sigma particle in J / psi ---> omega pi pi