Search for Production of Heavy Particles Decaying to Top Quarks and Invisible Particles in pp[over-bar] Collisions at [sqrt]s=1.96 TeV
We present a search for a new particle T′ decaying to top quark via T′-->t+X, where X is an invisible particle. In a data sample with 4.8 fb[superscript -1] of integrated luminosity collected by the CDF II detector at Fermilab in pp[over-bar] collisions with [sqrt]s=1.96 TeV, we search for pair...
| Main Authors: | , , , , |
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| Other Authors: | |
| Format: | Article |
| Language: | en_US |
| Published: |
American Physical Society
2011
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| Online Access: | http://hdl.handle.net/1721.1/67299 https://orcid.org/0000-0002-6047-4211 |
| Summary: | We present a search for a new particle T′ decaying to top quark via T′-->t+X, where X is an invisible particle. In a data sample with 4.8 fb[superscript -1] of integrated luminosity collected by the CDF II detector at Fermilab in pp[over-bar] collisions with [sqrt]s=1.96 TeV, we search for pair production of T′ in the lepton+jets channel, pp[over-bar] -->tt[over-bar] +X+X-->ℓνbqq′b+X+X. We interpret our results primarily in terms of a model where T′ are exotic fourth generation quarks and X are dark matter particles. Current direct and indirect bounds on such exotic quarks restrict their masses to be between 300 and 600 GeV/c[superscript 2], the dark matter particle mass being anywhere below mT′. The data are consistent with standard model expectations, and we set 95% confidence level limits on the generic production of T′T[over-bar] ′-->tt[over-bar] +X+X. For the dark matter model we exclude T′ at 95% confidence level up to mT′=360 GeV/c[superscript 2] for mX[less than or equal to]100 GeV/c[superscript 2]. |
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