AI Article Synopsis
- Researchers are investigating a new particle called T', which would decay into a top quark and another undetected particle (X).
- They conducted experiments using data from p p collisions at the Fermilab Tevatron, focusing on specific decay channels where T' pairs are produced.
- Their findings align with standard model predictions and establish a limit on the existence of T' as a fourth generation quark, excluding its presence up to a mass of 400 GeV/c² when considering X has a mass less than or equal to 70 GeV/c².
Article Abstract
We present a search for a new particle T' decaying to a top quark via T' → t + X, where X goes undetected. We use a data sample corresponding to 5.7 fb(-1) of integrated luminosity of p p collisions with sqrt[s] = 1.96 TeV, collected at Fermilab Tevatron by the CDF II detector. Our search for pair production of T' is focused on the hadronic decay channel, pp → T'T' → tt + XX → bqq b qq + XX. We interpret our results in terms of a model where T' is an exotic fourth generation quark and X is a dark matter particle. The data are consistent with standard model expectations. We set a limit on the generic production of T'T' → tt + XX, excluding the fourth generation exotic quarks T' at 95% confidence level up to m(T') = 400 GeV/c(2) for m(X) ≤ 70 GeV/c(2).
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| http://dx.doi.org/10.1103/PhysRevLett.107.191803 | DOI Listing |
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