The CCube reconstruction algorithm for the SoLid experiment Abreu, Y.; Amhis, Y.; Arnold, L. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
09/2024, Letnik:
1066
Journal Article
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The SoLid experiment is a very-short-baseline experiment aimed at searching for nuclear-reactor-produced active-to-sterile antineutrino oscillations. The detection principle is based on the pairing ...of two types of solid scintillators: polyvinyl toluene and 6LiF:ZnS(Ag), which is a new technology used in this field of Physics. In addition to good neutron-gamma discrimination, this setup allows the detector to be highly segmented (the basic detection unit is a 5 cm side cube). High segmentation provides numerous advantages, including the precise location of inverse beta decay (IBD) products, the derivation of the antineutrino energy estimator based on the isolated positron energy, and a powerful background reduction tool based on the topological signature of the signal. Finally, the system is read out by a network of wavelength-shifting (WLS) fibres coupled to a photodetectors. This paper describes the design of the reconstruction algorithm that allows maximum use of the granularity of the detector. The goal of the algorithm is to convert the output of the optical-fibre readout to the list of the detection units from which it originated. This paper provides a performance comparison for three methods and concludes with a choice of the baseline approach for the experiment.
Evidence of B + → τ + ν decays with hadronic B tags Grauges, E.; Palano, A.; Eigen, G. ...
Physical review. D, Particles, fields, gravitation, and cosmology,
08/2013, Letnik:
88, Številka:
3
Journal Article
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We present a search for the decay B + → τ + ν using 467.8 × 10 6 B ¯¯¯ B pairs collected at the Υ ( 4 S ) resonance with the BABAR detector at the SLAC PEP-II B -Factory. We select a sample of events ...with one completely reconstructed B − in the hadronic decay mode ( B − → D ( * ) 0 X − and B − → J / ψ X − ). We examine the rest of the event to search for a B + → τ + ν decay. We identify the τ + lepton in the following modes: τ + → e + ν ¯ ν , τ + → μ + ν ¯ ν , τ + → π + ¯ ν and τ + → ρ + ¯ ν . We find an excess of events with respect to the expected background, which excludes the null signal hypothesis at the level of 3.8 σ (including systematic uncertainties) and corresponds to a branching fraction value of B ( B + → τ + ν ) = ( 1.83 + 0.53 − 0.49 ( stat ) ± 0.24 ( syst ) ) × 10 − 4 .
In a sample of 471 × 10 6 B ¯¯¯ B events collected with the BABAR detector at the PEP-II e + e − collider we study the rare decays B → K ( * ) ℓ + ℓ − , where ℓ + ℓ − is either e + e − or μ + μ − . ...We report results on partial branching fractions and isospin asymmetries in seven bins of dilepton mass-squared. We further present C P and lepton-flavor asymmetries for dilepton masses below and above the J / ψ resonance. We find no evidence for C P or lepton-flavor violation. The partial branching fractions and isospin asymmetries are consistent with the Standard Model predictions and with results from other experiments.
We search for di-muon decays of a low-mass Higgs boson ( A 0 ) produced in radiative Υ ( 1 S ) decays. The Υ ( 1 S ) sample is selected by tagging the pion pair in the Υ ( 2 S , 3 S ) → π + π − Υ ( 1 ...S ) transitions, using a data sample of 92.8 × 10 6 Υ ( 2 S ) and 116.8 × 10 6 Υ ( 3 S ) events collected by the BABAR detector. We find no evidence for A 0 production and set 90% confidence level upper limits on the product branching fraction B ( Υ ( 1 S ) → γ A 0 ) × B ( A 0 → μ + μ − ) in the range of ( 0.28 − 9.7 ) × 10 − 6 for 0.212 ≤ m A 0 ≤ 9.20 GeV / c 2 . The results are combined with our previous measurements of Υ ( 2 S , 3 S ) → γ A 0 , A 0 → μ + μ − to set limits on the effective coupling of the b quark to the A 0 .
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