A search for a manifestly exotic S = -2 baryon state decaying to Xi(-) pi(-), and its neutral partner decaying to Xi(-) pi(+), has been performed using 220 pb(-1) of pp collisions at root s = 1.96 TeV collected by the Collider Detector at Fermilab. The Xi(-) trajectories were measured in a silicon tracker before their decay, resulting in a sample with low background and excellent position resolution. No evidence was found for S = -2 pentaquark candidates in the invariant mass range of 1600-2100 MeV/c(2). Upper limits on the product of pentaquark production cross section times its branching fraction to Xi(-) pi(+, -), relative to the cross section of the well-established Xi(1530) resonance, are presented for neutral and doubly negative candidates with p(T) > 2 GeV/c and vertical bar y vertical bar < 1 as a function of pentaquark mass. At 1862 MeV/c(2), these upper limits for neutral and doubly negative final states were found to be 3.2% and 1.7% at the 90% confidence level, respectively.

Search for exotic S =-2 baryons in p(p)over-bar collisions at root s=1.96 TeV

BISELLO, DARIO;BUSETTO, GIOVANNI;LUCCHESI, DONATELLA;ROSSIN, ROBERTO;
2007

Abstract

A search for a manifestly exotic S = -2 baryon state decaying to Xi(-) pi(-), and its neutral partner decaying to Xi(-) pi(+), has been performed using 220 pb(-1) of pp collisions at root s = 1.96 TeV collected by the Collider Detector at Fermilab. The Xi(-) trajectories were measured in a silicon tracker before their decay, resulting in a sample with low background and excellent position resolution. No evidence was found for S = -2 pentaquark candidates in the invariant mass range of 1600-2100 MeV/c(2). Upper limits on the product of pentaquark production cross section times its branching fraction to Xi(-) pi(+, -), relative to the cross section of the well-established Xi(1530) resonance, are presented for neutral and doubly negative candidates with p(T) > 2 GeV/c and vertical bar y vertical bar < 1 as a function of pentaquark mass. At 1862 MeV/c(2), these upper limits for neutral and doubly negative final states were found to be 3.2% and 1.7% at the 90% confidence level, respectively.
File in questo prodotto:
Non ci sono file associati a questo prodotto.
Pubblicazioni consigliate

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: https://hdl.handle.net/11577/2535972
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 6
  • ???jsp.display-item.citation.isi??? 6
  • OpenAlex ND
social impact