23122779
Search for new physics in the multijet and missing transverse momentum final state in proton-proton collisions at √s = 7 TeV.
A search for physics beyond the standard model is performed in events with at least three jets and large missing transverse momentum produced in proton-proton collisions at a center-of-mass energy of √s=7 TeV. No significant excess of events above the expected backgrounds is observed in 4.98 fb(-1) of data collected with the CMS detector at the Large Hadron Collider. The results are presented in the context of the constrained minimal supersymmetric extension of the standard model and more generically for simplified models. For the simplified models of gluino-gluino and squark-squark production, gluino masses below 1.0 TeV and squark masses below 0.76 TeV are excluded in case the lightest supersymmetric particle mass is below 200 GeV. These results significantly extend previous searches.
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.
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).
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.
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.
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.
55435603
Radon contribution to single particle counts of the ARGO-YBJ detector
The ARGO-YBJ experiment is an air shower detector for gamma ray astronomy and cosmic ray studies with an energy threshold of ∼500 GeV. Working in “single particle mode”, i.e. counting the single particles hitting the detector at fixed time intervals, ARGO-YBJ can monitor cosmic ray and gamma ray transients at energies of a few GeV. 
 
The single particle counting rate is modulated by the atmospheric pressure and temperature, and is affected by the local radioactivity from soil and air. Among the radioactive elements, radon gas is of particular importance since its concentration in air can vary significantly, according to environmental conditions. In this paper we evaluate the contribution of the radon daughter gamma ray emitters to the single particle counting rate measured by ARGO-YBJ. According to our analysis, the radon gas contribution is roughly 1–2%, producing a counting rate modulation of the same order of magnitude of the atmospheric effects.
123410881
Test of the hadronic interaction models at around *10 TeV with Tibet EAS core data
A hybrid experiment has been started by ASγ collaboration at Tibet, China, since May 2009, that consists of a burst-detector-grid (YAC, Yangbajing Air shower Core array) and the Tibet air-shower array (Tibet-III). The first step of YAC, called YAC-I, contains 16 detector units and observes high energy electromagnetic particles in air-shower cores within several meters from the shower axis, and Tibet-III array measures the total energy and the arrival direction of air showers. YAC-I is used to check hadronic interaction models currently used for air-shower simulations such as QGSJET, SIBYLL , EPOS etc. through the multi-parameter measurement in air-shower cores. In this paper, we used a data set collected from May 1st 2009 through February 23rd 2010 by the YAC-I. The effective live time used for the present analysis is 169.65 days. The preliminary results of the interaction model checking at *10 TeV energy region is reported in this paper.
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
124551811
The forward particle production in the energy range of 1 PeV as seen with the Tibet hybrid experiment
We are now operating the 500 m Yangbajing air-shower core (YAC-II) array near the center of the Tibet air-shower array ( Tibet-III ) to observe cosmic-ray chemical composition at the knee energy region since February 2011. The first step of YAC, called YAC-I, containing 16 detector units, was operated from May, 2009 to February, 2010. In this paper, we used the YAC-I and Tibet-III coincident data set obtained from May, 2009 through January, 2010 to present the electromagnetic spectrum of air shower cores at around 10 eV energy region. The effective live time is calculated as 100.5 days. We would like to report the comparison of our experimental data with MC model prediction in this paper.
52993839
OBSERVATION OF TeV GAMMA RAYS FROM THE UNIDENTIFIED SOURCE HESS J1841–055 WITH THE ARGO-YBJ EXPERIMENT
We report the observation of a very high energy γ-ray source whose position is coincident with HESS J1841–055. This source has been observed for 4.5 years by the ARGO-YBJ experiment from 2007 November to 2012 July. Its emission is detected with a statistical significance of 5.3 standard deviations. Parameterizing the source shape with a two-dimensional Gaussian function, we estimate an extension , which is consistent with the HESS measurement. The observed energy spectrum is dN/dE = (9.0 ± 1.6) × 10–13(E/5 TeV)–2.32 ± 0.23 photons cm–2 s–1 TeV–1, in the energy range 0.9-50 TeV. The integral γ-ray flux above 1 TeV is 1.3 ± 0.4 Crab, which is 3.2 ± 1.0 times the flux derived by HESS. The differences in the flux determination between HESS and ARGO-YBJ and possible counterparts at other wavelengths are discussed.