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in creator/contributor: "/Pisa, Scuola Normale Superiore"

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First observation of the Bs->K+K- decay mode, and measurement of the B0 and Bs mesons decay-rates into two-body charmless final states at CDF

The authors searched for decays of the type B{sub (s)}{sup 0} {yields} h{sup +}h{prime}{sup -} (where h, h{prime} = K or {pi}) in a sample corresponding to 180 pb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV, collected by the upgraded Collider Detector at the Fermilab Tevatron. A total signal of approximately 900 events was reconstructed, and the relative branching fractions ({Beta}) of each decay mode were determined with a likelihood fit.

Date: November 1, 2006

Creator: Tonelli, Diego & /Pisa, Scuola Normale Superiore

Item Type: Thesis or Dissertation

Partner: UNT Libraries Government Documents Department

open access

Measurements of CP asymmetries and branching fractions of two-body charmless decays of B^0 and B^0_s mesons

The thesis is organized as follows: Chapter 1 describes the theoretical framework of non-leptonic B{sub (s)}{sup 0} {yields} H{sup +}h{prime}{sup -} decays, with a simple overview of the CP violation mechanism within the Standard Model and of the most used phenomenological approaches in the evaluation of strong interaction contributions. The chapter contains also a review of the theoretical expectations and the current experimental measurements along with a discussion about the importance of st… more

Date: December 1, 2007

Creator: Morello, Michael Joseph & /Pisa, Scuola Normale Superiore

Item Type: Thesis or Dissertation

Partner: UNT Libraries Government Documents Department

open access

Branching fractions and direct CP asymmetries of charmless decay modes at the Tevatron

The authors present new CDF results on the branching fractions and time-integrated direct CP asymmetries for B{sup 0} and B{sub s}{sup 0} decay modes into pairs of charmless charged hadrons (pion or kaon). The data set for this update amounts to 1 fb{sup -1} of {bar p}p collisions at {radical}s = 1.96 TeV. They report the first observation of the B{sub s}{sup 0} {yields} K{sup -}{pi}{sup +} mode and a measurement of its branching fraction and direct CP asymmetry. They also observe for the first… more

Date: December 1, 2006

Creator: Morello, Michael & /Pisa, Scuola Normale Superiore /INFN, Pisa

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Branching fractions and CP asymmetries in B ---> H+ Hh'-

Relative branching fractions of B{sub d,s} {yields} h{sup +}h'{sup -} decays (where h, h' = K or {pi}) and direct CP asymmetry in B{sub d} {yields} K{sup +}{pi}{sup -} have been measured with 180 pb{sup -1} of data collected by the CDFII detector at the Tevatron collider. This includes the first BR measurement of a charmless B{sub s} {yields} PP decay (B{sub s} {yields} K{sup +}K{sup -}).

Date: April 1, 2005

Creator: Punzi, Giovanni & /Pisa, Scuola Normale Superiore /INFN, Pisa

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Measurement of the Tau Lepton Lifetime with BaBar

The mean lifetime of the tau lepton is measured from the decay length distribution of 3-prong tau decays from e{sup +}e{sup -} collisions at the {Upsilon}(4S) resonance. A data sample of 80.0 fb{sup -1} collected with the BABAR detector at the PEP-II B Factory is used for this measurement. The measured tau lifetime is: {tau}{sub {tau}} = 289.40 {+-} 0.91 (stat.) {+-} 0.90 (syst.) fs. All the results are preliminary.

Date: June 27, 2005

Creator: Lusiani, A. & /Pisa, Scuola Normale Superiore /INFN, Pisa

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

BaBar Tests of Lorentz and CPT Symmetry

Tests of CPT and T symmetries and a limit on the difference between the decay rates of the two mass eigenstates in B{sup 0}-mesons oscillations are reported. The reconstructed B decays, comprising both CP and flavor eigenstates, are obtained from {Upsilon}(4S) {yields} B{bar B} decays collected by the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. Sensitivity projections for sidereal time modulation of the CPT-violating parameter based on an explicit and general CPT-breaking … more

Date: August 24, 2005

Creator: Martinez-Vidal, F. & /Valencia U. /Pisa, Scuola Normale Superiore /Pisa U. /INFN, Pisa

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

On the escape of particles from cosmic ray modified shocks

The solution of the problem of particle acceleration in the non-linear regime, when the dynamical reaction of the accelerated particles cannot be neglected, shows strong shock modification.When stationarity is imposed by hand, the solution may show a prominent energy flux away from the shock towards upstream infinity. This feature is peculiar of cosmic ray modified shocks, while being energetically insignificant in the test particle regime. The escape flux appears also in situations in which it… more

Date: July 1, 2008

Creator: Caprioli, D.; /Pisa, Scuola Normale Superiore; Blasi, P.; /Fermilab, /Arcetri Observ.; Amato, E. & Observ., /Arcetri

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Dynamical Feedback of Self-generated Magnetic Fields in Cosmic Rays Modified Shocks

We present a semi-analytical kinetic calculation of the process of non-linear diffusive shock acceleration (NLDSA) which includes magnetic field amplification due to cosmic ray induced streaming instability, the dynamical reaction of the amplified magnetic field and the possible effects of turbulent heating. This kinetic calculation allows us to show that the net effect of the amplified magnetic field is to enhance the maximum momentum of accelerated particles while reducing the concavity of th… more

Date: July 1, 2008

Creator: Caprioli, D.; /Pisa, Scuola Normale Superiore; Blasi, P.; /Fermilab, /Arcetri Observ.; Amato, E.; Observ., /Arcetri et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Study of sequential semileptonic decays of b hadrons produced at the Tevatron

The authors present a study of rates and kinematical properties of lepton pairs contained in central jets with transverse energy E{sub T} {ge} 15 GeV that re produced at the Fermilab Tevatron collider. They compare the data to a QCD prediction based on the HERWIG and QQ Monte Carlo generator programs. They find that the data are poorly described by the simulation, in which sequential semileptonic decays of single b quarks (b {yields} l c X with c {yields} l s X) are the major source of such lep… more

Date: July 1, 2005

Creator: Apollinari, G.; Fiori, I.; Giromini, P.; Happacher, F.; Miscetti, S.; Parri, A. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Contraints on New Physics in MFV models: a model-independent analysis of \DeltaF=1 processes

We analyze the constraints on dimension-six {Delta}F = 1 effective operators in models respecting the MFV hypothesis, both in the one-Higgs doublet case and in the two-Higgs doublet scenario with large tan {beta}. The constraints are derived mainly from the b {yields} s inclusive observables measured at the B factories. The implications of these bounds in view of improved measurements in exclusive and inclusive observables in b {yields} s{ell}{sup +}{ell}{sup -} and s {yields} d{nu}{bar {nu}} t… more

Date: November 5, 2008

Creator: Hurth, Tobias; /SLAC, /CERN; Isidori, Gino; /Pisa, Scuola Normale Superiore /INFN, Pisa /Frascati; Kamenik, Jernej F.; /Frascati /Stefan Inst., Ljubljana et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Search for narrow resonances below the Upsilon mesons

The authors have investigated the invariant mass spectrum of dimuons collected by the CDF experiment during the 1992-1995 run of the Fermilab Tevatron collider to improve the limit on the existence of narrow resonances set by the experiments at the SPEAR e{sup +}e{sup -} collider. In the mass range 6.3-9.0 GeV/c{sup 2} they derive an average 90% upper credible limit of 8 eV to the leptonic width of possible resonances. This limit is much worse at the mass of 7.2 GeV/c{sup 2} due to an excess of… more

Date: July 1, 2005

Creator: Apollinari, G.; Barone, M.; Carithers, W.; Dell'Orso, M.; Dorigo, T.; Fiori, I et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Design and Initial Tests of the Tracker-Converter ofthe Gamma-ray Large Area Space Telescope

The Tracker subsystem of the Large Area Telescope (LAT) science instrument of the Gamma-ray Large Area Space Telescope (GLAST) mission has been completed and tested. It is the central detector subsystem of the LAT and serves both to convert an incident gamma-ray into an electron-positron pair and to track the pair in order to measure the gamma-ray direction. It also provides the principal trigger for the LAT. The Tracker uses silicon strip detectors, read out by custom electronics, to detect ch… more

Date: April 16, 2007

Creator: Atwood, W.B.; Bagagli, R.; Baldini, L.; Bellazzini, R.; Barbiellini, G.; Belli, F. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Search for Higgs bosons decaying into b anti-b and produced in association with a vector boson in p anti-p collisions at 1.8-TeV

The authors present a new search for H{sup 0}V production, where H{sup 0} is a scalar Higgs boson decaying into b{bar b} with branching ratio {beta}, and V is a Z{sup 0} boson decaying into e{sup +}e{sup -}, {mu}{sup +}{mu}{sup -}, or {nu}{bar {nu}}. This search is then combined with previous searches for H{sup 0}V where V is a W{sup {+-}} boson or a hadronically decaying Z{sup 0}. The data sample consists of 106 {+-} 4 pb{sup -1} or p{bar p} collisions at {radical}s = 1.8 TeV accumulated by th… more

Date: March 1, 2005

Creator: Acosta, D.; Affolder, Anthony A.; Albrow, M. G.; Ambrose, D.; Amidei, D.; Anikeev, K. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

SuperB Progress Report: Detector

This report describes the present status of the detector design for SuperB. It is one of four separate progress reports that, taken collectively, describe progress made on the SuperB Project since the publication of the SuperB Conceptual Design Report in 2007 and the Proceedings of SuperB Workshop VI in Valencia in 2008.

Date: February 14, 2012

Creator: Grauges, E.; /Barcelona U., ECM; Donvito, G.; Spinoso, V.; /INFN, Bari /Bari U.; Manghisoni, M. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department