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(-1) of integrated luminosity collected by the CDF II detector at Fermilab in p (p) over bar collisions with root s = 1.96 TeV, we search for pair production of T' in the lepton + jets channel, p (p) over bar -> t (t) over bar + X + X -> lvbqq'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(2), the dark matter particle mass being anywhere below m(T'). The data are consistent with standard model expectations, and we set 95% confidence level limits on the generic production of T'(T) over bar -> t (t) over bar + X + X. For the dark matter model we exclude T' at 95% confidence level up to m(T)' = 360 GeV/c(2) for m(X) <= 100 GeV/c(2).

Search for Production of Heavy Particles Decaying to Top Quarks and Invisible Particles in p(p)over-bar Collisions at root s=1.96 TeV

INTROZZI, GIANLUCA;
2011

Abstract

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(-1) of integrated luminosity collected by the CDF II detector at Fermilab in p (p) over bar collisions with root s = 1.96 TeV, we search for pair production of T' in the lepton + jets channel, p (p) over bar -> t (t) over bar + X + X -> lvbqq'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(2), the dark matter particle mass being anywhere below m(T'). The data are consistent with standard model expectations, and we set 95% confidence level limits on the generic production of T'(T) over bar -> t (t) over bar + X + X. For the dark matter model we exclude T' at 95% confidence level up to m(T)' = 360 GeV/c(2) for m(X) <= 100 GeV/c(2).
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/11571/570830
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 28
  • ???jsp.display-item.citation.isi??? 31
social impact