We present a measurement of the B(0) -> (Lambda) over barp pi(-) branching fraction performed using the BABAR detector at the PEP-II asymmetric e(+)e(-) collider. Based on a sample of 467 x 10(6) B (B) over bar pairs we measure B(B(0) -> (Lambda) over barp pi(-)) = [3.07 +/- 0.31(stat) +/- 0.23(syst)] x 10(-6). The measured differential spectrum as a function of the dibaryon invariant mass m((Lambda) over barp) shows a near-threshold enhancement similar to that observed in other baryonic B decays. We study the (Lambda) over bar polarization as a function of (Lambda) over bar energy in the B(0) rest frame (E((Lambda) over bar)*) and compare it with theoretical expectations of fully longitudinally right-polarized (Lambda) over bar at large E((Lambda) over bar)*.
Measurement of the branching fraction and (Lambda)over-bar polarization in B(0)->(Lambda)over bar p pi(-) RID C-5223-2009
ANGELINI, CARLO;BATIGNANI, GIOVANNI;BETTARINI, STEFANO;CALDERINI, GIOVANNI;FORTI, FRANCESCO;GIORGI, MARCELLO;PAOLONI, EUGENIO;RIZZO, GIULIANA;
2009-01-01
Abstract
We present a measurement of the B(0) -> (Lambda) over barp pi(-) branching fraction performed using the BABAR detector at the PEP-II asymmetric e(+)e(-) collider. Based on a sample of 467 x 10(6) B (B) over bar pairs we measure B(B(0) -> (Lambda) over barp pi(-)) = [3.07 +/- 0.31(stat) +/- 0.23(syst)] x 10(-6). The measured differential spectrum as a function of the dibaryon invariant mass m((Lambda) over barp) shows a near-threshold enhancement similar to that observed in other baryonic B decays. We study the (Lambda) over bar polarization as a function of (Lambda) over bar energy in the B(0) rest frame (E((Lambda) over bar)*) and compare it with theoretical expectations of fully longitudinally right-polarized (Lambda) over bar at large E((Lambda) over bar)*.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
