Evidence for B¯s0→Λc+Λ¯π Adachi, I.; Asner, D. M.; Aushev, T. ...
Physics letters. B,
08/2013, Letnik:
726, Številka:
1-3
Journal Article
Recenzirano
Odprti dostop
Using 121.4 fb–1 of data collected with the Belle detector at the Y(5S) resonance at the KEKB asymmetric-energy e+e- collider, we report evidence for the B¯$^{0}_{s}$ → Λ$^{+}_{c}$Λ¯π– decay mode ...with a measured branching fraction (3.6 ± 1.1stat.$^{+0.3}_{-0.5}$syst. ± 0.9Λ$^{+}_{c}$ ± 0.7 NB¯$^{0}_{s}$) x 10–4 and a significance of 4.4 standard deviations. Here, this is the first evidence for a baryonic B$^{0}_{s}$ decay.
The Belle II Physics Book Kou, E; Beneke, M; Crivellin, A ...
Progress of theoretical and experimental physics,
12/2019, Letnik:
2019, Številka:
12
Journal Article
Recenzirano
Odprti dostop
We present the physics program of the Belle II experiment, located on the intensity frontier SuperKEKB e+e- collider. Belle II collected its first collisions in 2018, and is expected to operate for ...the next decade. It is anticipated to collect 50/ab of collision data over its lifetime. This book is the outcome of a joint effort of Belle II collaborators and theorists through the Belle II theory interface platform (B2TiP), an effort that commenced in 2014. The aim of B2TiP was to elucidate the potential impacts of the Belle II program, which includes a wide scope of physics topics: B physics, charm, tau, quarkonium, electroweak precision measurements and dark sector searches. It is composed of nine working groups (WGs), which are coordinated by teams of theorist and experimentalists conveners: Semileptonic and leptonic B decays, Radiative and Electroweak penguins, phi_1 and phi_2 (time-dependent CP violation) measurements, phi_3 measurements, Charmless hadronic B decay, Charm, Quarkonium(like), tau and low-multiplicity processes, new physics and global fit analyses. This book highlights "golden- and silver-channels", i.e. those that would have the highest potential impact in the field. Theorists scrutinised the role of those measurements and estimated the respective theoretical uncertainties, achievable now as well as prospects for the future. Experimentalists investigated the expected improvements with the large dataset expected from Belle II, taking into account improved performance from the upgraded detector.
The security system of personal radiographic inspection for detection of explosive materials and plastic weapons was developed in BINP recently. Basic system parameters are: maximum scanning height—
...2000
mm
, image width—
800
mm
, number of detector channels—768, channel size—
1.05×1
mm
, charge collecting time for one line—2,
5
ms
, scanning speed—
40
cm/s
, maximum scanning time—
5
s
, radiation dose per one inspection
<5
μSv
. The detector is a multichannel ionization Xe chamber. The image of inspected person will appear on the display just after scanning. The pilot sample of this system was put into operation in March, 2003.b
Broadband dielectric spectroscopy from Hz up to the infrared (IR) range and temperature interval 10-300 K was carried out for xBaZrO3-(1-x)BaTiO3 (BZT-x, x = 0.6, 0.7, 0.8) solid solution ceramics ...and compared with similar studies for x = 0, 0.2, 0.4, 1 ceramics published recently (Phys. Rev. B 86, 014106 (2012)). Rather complex IR spectra without appreciable mode softening are ascribed to Last-Slater transverse optic (TO) phonon eigenvector mixing and possible two-mode mixed crystal behavior. Fitting of the complete spectral range requires a relaxation in the 100 GHz range for all the samples. Below 1 GHz another relaxation appears, which is thermally activated and obeys the same Arrhenius behavior for all the relaxor BZT samples. The frequently reported Vogel-Fulcher behavior in BZT relaxors is shown to be an artifact of the evaluation from the permittivity or loss vs. temperature dependences instead of its evaluation from loss vs. frequency maxima. The relaxation is assigned to local hopping of the off-centered Ti4+ ions in the frozen BTO clusters, whose size is rather small and cannot grow on cooling. Therefore BZT is to be considered as a dipolar glass rather than relaxor ferroelectric.
We report measurements of B→χc1γK and χc2γK decays using 772×106 B B¯ events collected at the Υ ( 4S ) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. Evidence of a new ...resonance in the χc1γ final state is found with a statistical significance of 3.8σ . This state has a mass of 3823.1±1.8 ( stat ) ±0.7 ( syst ) MeV/c2 , a value that is consistent with theoretical expectations for the previously unseen 1D23 c c¯ meson. We find no other narrow resonance and set upper limits on the branching fractions of the X ( 3872 ) →χc1γ and χc2γ decays.
The phenomenon of a significant increase in the photoinduced changes in refractive index, non-linear refraction, and nonlinear third-order optical susceptibility in organic materials based on ...polyimides, pyridines, and prolinols upon the introduction of fullerenes and carbon nanotubes (CNTs) into the organic matrix is briefly considered (with emphasis on the dominating effect of CNTs). It is established that the values of these photorefractive parameters determined in said fullerene- and CNT-doped materials using a four-wave-mixing scheme are close to the analogous values in bulk silicon-based materials. The results can be useful in developing thin-film nonlinear filters, thin diffraction gratings for passive data recording, and optically-addressed light modulators, in medical applications, and in display technology (e.g., for creating a three-dimensional medium prototype).