Search for new physics in final states with low transverse energy photon and missing transverse energy in proton-proton collisions at $\sqrt{s} = 8$ TeV [electronic resource]

• Ngôn ngữ: eng
• Ký hiệu phân loại: 530.14 Field and wave theories
• Thông tin xuất bản: Washington, D.C. : Oak Ridge, Tenn. : United States. Dept. of Energy. Office of High Energy Physics ; Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2015
• Mô tả vật lý: Size: 121 p. : , digital, PDF file.
• Bộ sưu tập: Metadata
• ID: 268228
• Chủ đề: 1. 72 physics of elementary particles and fields; 2. Photons; 3. Proton-proton interactions; 4. Tev range 01-10; 5. Transverse momentum

Tóm tắt

 A search for new physics in the ?+E<
 sub>
 T<
 /sub>
  final state is performed using pp collision data corresponding to an integrated luminosity of 7.3 fb<
 sup>
 -1<
 /sup>
  collected at ?s = 8 TeV using low threshold triggers in a phase space region defined by E<
 sub>
 T<
 /sub>
  >
  45 GeV and E-slash<
 sub>
 T<
 /sub>
  >
  40 GeV. The data are also examined using optimized selections for maximum sensitivity to an exotic (gravitino/neutralino) decay of the Higgs boson predicted in a low-scale SUSY breaking scenario. The results are found to be compatible with the Standard Model hypothesis. These results are the first limits on this model from collider searches. Furthermore, proton-proton collision events containing high-energy photon and missing transverse momentum have been investigated. No deviations from the standard model have been observed using the ?s = 8 TeV data set corresponding to 19.6 fb<
 sup>
 -1<
 /sup>
  of integrated luminosity. Further constraints are set on ? production and translated into upper limits on vector and axial-vector contributions to the ?-nucleon scattering cross section. For M<
 sub>
 ?<
 /sub>
  = 10 GeV, the ?-nucleon cross section is constrained to be 2.6 x 10<
 sup>
 -39<
 /sup>
  cm<
 sup>
 2<
 /sup>
  (9.6 x 10<
 sup>
 -41<
 /sup>
  cm<
 sup>
 2<
 /sup>
 ) for a spin-independent (spin-dependent) interaction at 90% confidence level. In addition the most stringent limits to date are obtained on the effective Planck scale in the ADD model with large spatial extra dimensions and on the brane tension scale in the branon model.