The LHCb simulation application, Gauss, consists of two independent phases, the generation of the primary event and the tracking of particles produced in the experimental setup. For the LHCb ...experimental program it is particularly important to model B meson decays: the EvtGen code developed in CLEO and BABAR has been chosen and customized for non-coherent B production as occuring in pp collisions at the LHC. The initial proton-proton collision is provided by a different generator engine, currently PYTHIA 6 for massive production of signal and generic pp collisions events. Beam gas events, background events originating from proton halo, cosmics and calibration events for different detectors can be generated in addition to pp collisions. Different generator packages as available in the physics community or specifically developed in LHCb are used for the different purposes. Running conditions affecting the generated events such as the size of the luminous region, the number of collisions occuring in a bunch crossing and the number of spill-over events from neighbouring bunches are modeled via dedicated algorithms appropriately configured. The design of the generator phase of Gauss will be described: a modular structure with well defined interfaces specific to the various tasks, e.g. pp collisions, particle decays, selections, etc. has been chosen. Different implementations are available for the various tasks allowing selecting and combining them as most appropriate at run time as in the case of PYTHIA 6 for pp collisions or HIJING for beam gas. The advantages of such structure, allowing for example to adopt transparently new generators packages, will be discussed.
The status of the unitary triangle beyond the standard model including the most recent results on Deltams on dilepton asymmetries and on width differences is presented. Even allowing for general new ...physics loop contributions the unitarity triangle must be very close to the standard model result. With the new measurements from the Fermilab Tevatron, we obtain for the first time a significant constraint on new physics in the Bs sector. We present the allowed ranges of new physics contributions to DeltaF=2 processes and of the time-dependent CP asymmetry in Bs-->J/psivarphi decays.
The recently measured B→τν branching ratio allows to test the Standard Model by probing virtual effects of new heavy particles, such as a charged Higgs boson. The accuracy of the test is currently ...limited by the experimental error on BR(B→τν) and by the uncertainty on the parameters fB and |Vub|. The redundancy of the Unitarity Triangle fit allows to reduce the error on these parameters and thus to perform a more precise test of the Standard Model. Using the current experimental inputs, we obtain BR(B→τν)SM=(0.84±0.11)×10−4, to be compared with BR(B→τν)exp=(1.73±0.34)×10−4. The Standard Model prediction can be modified by New Physics effects in the decay amplitude as well as in the Unitarity Triangle fit. We discuss how to disentangle the two possible contributions in the case of minimal flavour violation at large tanβ and generic loop-mediated New Physics. We also consider two specific models with minimal flavour violation: the Type-II Two Higgs Doublet Model and the Minimal Supersymmetric Standard Model.
A
bstract
We update the analysis of
D
meson mixing including the latest experimental results as of January 2014. We derive constraints on the parameters
M
12
, Γ
12
and Φ
12
that describe
D
meson ...mixing using all available data, allowing for CP violation. We also provide posterior distributions for observable parameters appearing in
D
physics.
To assess whether the addition of clinical Gleason score (Gs) 3+4 to the Prostate Cancer Research International: Active Surveillance (PRIAS) criteria affects pathologic results in patients who are ...potentially suitable for active surveillance (AS) and to identify possible clinical predictors of unfavourable outcome.
Three hundred and twenty-nine men who underwent radical prostatectomy with complete clinical and follow-up data and who would have fulfilled the inclusion criteria of the PRIAS protocol at the time of biopsy except for the addition of biopsy Gs=3+4 and with at least 10 cores taken have been evaluated. One experienced genitourinary pathologist selected those with real Gs=3+3 and 3+4 in only one core according to the 2005 International Society of Urological Pathology criteria. The primary end point was the proportion of unfavourable outcome (nonorgan confined disease or Gs⩾4+3). Logistic regressions explored the association between preoperative characteristics and the primary end point.
Two hundred and four patients were evaluated and 46 (22.5%) patients harboured unfavourable disease at final pathology. After a median follow-up of 73.5 months, there was no cancer-specific death, and 4 (2.0%) patients had biochemical relapse. There were no significant differences in terms of high Gs, locally advanced disease, unfavourable disease and biochemical relapse-free survival among patients with clinical Gs=3+3 vs Gs=3+4. At multivariable analysis, the presence of atypical small acinar proliferation (ASAP) and lower number of core taken were independently associated with a higher risk of unfavourable disease.
The inclusion of Gs=3+4 in patients suitable to AS does not enhance the risk of unfavourable disease after radical prostatectomy. Additional factors such as number of cores taken and the presence of ASAP should be considered in patients suitable for AS.
The LHCb simulation application. Gauss, consists or two independent phases, the generation of the primary event and the tracking of particles produced in the experimental setup. For the LHCh ...experimental program it is particularly important to model B meson decays: the EvtGcn code developed in CLEO and BaBah has been chosen and customized for non-coherent B production as occurring in pp collisions at the LHC, The initial proton-proton collision is provided by a different generator engine, currently PYTHIA 6 for massive production of signal and generic pp collisions events. Beam gas events, background events originating from proton halo, cosmics and calibration events for different detectors can be generated in addition to pp collisions. Different generator packages as available in the physics community or specifically developed in LHCb are used for the different purposes. Running conditions affecting the events generated such as the size of the luminous region, the number of collisions occuring in a bunch crossing and the number of spill-over events from neighbouring bunches are modeled via dedicated algorithms appropriately configured. The design of the generator phase of Gauss will be described: a modular structure with well defined interfaces specific to the various tasks, e.g. pp collisions, particles' decays, selections, etc. has been chosen. Different implementations are available for the various tasks allowing selecting and combining them as most appropriate at run time as in the case of Pythia 6 im pp collisions or HIJING for beam gas. The advantages of such structure, allowing for example to adopt transparently new generators packages will be discussed.
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