Search results for " weak D"

Pion radiative weak decays in nonlocal chiral quark models

2010

We analyze the radiative pion decay pi+ -> e+ nu_e gamma within nonlocal chiral quark models that include wave function renormalization. In this framework we calculate the vector and axial-vector form factors FV and FA at q^2=0 --where q^2 is the (e+ ��_e) squared invariant mass-- and the slope a of FV(q^2) at q^2 -> 0. The calculations are carried out considering different nonlocal form factors, in particular those taken from lattice QCD evaluations, showing a reasonable agreement with the corresponding experimental data. The comparison of our results with those obtained in the (local) NJL model and the relation of FV and a with the form factor in pi^0 -> gamma* gamma decays are d…

Weak D and partial D: our experience in daily activity

2011

Coherent Conditional Previsions and Proper Scoring Rules

2012

In this paper we study the relationship between the notion of coherence for conditional prevision assessments on a family of finite conditional random quantities and the notion of admissibility with respect to bounded strictly proper scoring rules. Our work extends recent results given by the last two authors of this paper on the equivalence between coherence and admissibility for conditional probability assessments. In order to prove that admissibility implies coherence a key role is played by the notion of Bregman divergence.

Precision Measurement of the Mass and Lifetime of the Xi(-)(b) Baryon

2016

We report on measurements of the mass and lifetime of the Ξ[- over b] baryon using about 1800 Ξ[- over b] decays reconstructed in a proton-proton collision data set corresponding to an integrated luminosity of 3.0  fb[superscript -1] collected by the LHCb experiment. The decays are reconstructed in the Ξ[- over b] → Ξ[0 over c]π[superscript -], Ξ[0 over c] → pK[superscript -]K[superscript -]π[superscript +] channel and the mass and lifetime are measured using the Λ[0 over b] → Λ[+ over c]π[superscript -] mode as a reference. We measure M(Ξ[- over b] - M(Λ[0 over b]) = 178.36 ± 0.46 ± 0.16  MeV/c[superscript 2], (τ[subscript Ξ[- over b]/τ[subscript Λ[0 over b]) = 1.089 ± 0.026 ± 0.011, where…

Jet fragmentation transverse momentum distributions in pp and p-Pb collisions at √s, √sNN = 5.02 TeV

2021

Jet fragmentation transverse momentum (jT) distributions are measured in proton-proton (pp) and proton-lead (p-Pb) collisions at √sNN = 5.02 TeV with the ALICE experiment at the LHC. Jets are reconstructed with the ALICE tracking detectors and electromagnetic calorimeter using the anti-kT algorithm with resolution parameter R = 0.4 in the pseudorapidity range |η| < 0.25. The jT values are calculated for charged particles inside a fixed cone with a radius R = 0.4 around the reconstructed jet axis. The measured jT distributions are compared with a variety of parton-shower models. Herwig and Pythia 8 based models describe the data well for the higher jT region, while they underestimate the low…

Coherent conditional probabilities and proper scoring rules

2011

In this paper we study the relationship between the notion of coherence for conditional probability assessments on a family of conditional events and the notion of admissibility with respect to scoring rules. By extending a recent result given in literature for unconditional events, we prove, for any given strictly proper scoring rule s, the equivalence between the coherence of a conditional probability assessment and its admissibility with respect to s. In this paper we focus our analysis on the case of continuous bounded scoring rules. In this context a key role is also played by Bregman divergence and by a related theoretical aspect. Finally, we briefly illustrate a possible way of defin…