Next-to-leading order QCD predictions for the signal of dark matter and photon associated production at the LHC
Abstract
We study the potential of the LHC to discover the signal of dark matter associated production with a photon induced by a dimension six effective operator, including next-to-leading order QCD corrections. We investigate the main backgrounds from the standard model, i.e. Z boson and a photon associated production with invisible decay of Z boson, and Z boson and a jet production with the jet misidentified as a photon. We find that the pTγ distributions of the backgrounds decrease faster than that of the signal with increasing of the transverse momentum of the photon. The ηγ distributions of the backgrounds are almost flat in the full range of ηγ. In contrast, the signal lies mainly in the central region of ηγ. These characteristics may help to select the events in experiments. We show that in the parameter space allowed by the relic abundance constraint, which we have calculated at the next-to-leading-order QCD level, the LHC with S=7TeV may discover this signal at the 5σ level after collecting an integrated luminosity of 1fb-1. On the other hand, if this signal is not observed at the LHC, we can set a lower limit on the new physics scale at the 3σ level.
- Publication:
-
Physical Review D
- Pub Date:
- October 2011
- DOI:
- 10.1103/PhysRevD.84.075011
- arXiv:
- arXiv:1107.2048
- Bibcode:
- 2011PhRvD..84g5011W
- Keywords:
-
- 12.38.Bx;
- 14.65.Jk;
- 14.70.Bh;
- 95.35.+d;
- Perturbative calculations;
- Photons;
- Dark matter;
- High Energy Physics - Phenomenology;
- High Energy Physics - Experiment
- E-Print:
- 20 pages, 14 figures, version published in Phys.Rev.D