106 research outputs found
Search for the Electric Dipole Moment of the tau Lepton
We have searched for a CP violation signature arising from an electric dipole
moment (d_tau) of the tau lepton in the e+e- -> tau+tau- reaction. Using an
optimal observable method and 29.5 fb^{-1} of data collected with the Belle
detector at the KEKB collider at sqrt{s} = 10.58 GeV, we find Re(d_tau) = (1.15
+- 1.70) x 10^{-17} ecm and Im(d_tau) = (-0.83 +- 0.86) x 10^{-17} ecm and set
the 95% confidence level limits -2.2 < Re(d_tau) < 4.5 (10^{-17}ecm) and -2.5 <
Im(d_tau) < 0.8 (10^{-17}ecm).Comment: 15 pages, LaTeX, 21 figures, submitted to Phys. Lett.
Electron accelerator for energy up to 5.0 MeV and beam power up to 50 kW with Х-ray converter
The paper describes the industrial electron accelerator ILU-10 for electron energy up to 5 MeV and beam power
up to 50 kW specially designed for use in industrial applications. The ILU-10 accelerator generates the vertical electron beam. The beam line turns the beam through an angle of 90° and transports the beam to the vertically posed Xray converter to generate the horizontal beam of X-rays.Приводиться опис прискорювача електронів ІЛУ-10 на енергію 5 МеВ потужністю 50 кВт, спеціально
розробленого для таких комплексів. Для спрощення конструкції конвеєрної системи подачі оброблюваної
продукції в зону опромінення використовується випускний пристрій з поворотом пучка на 90 градусів інаступною конвертацією електронного пучка в гамма-випромінювання на вертикально розташованій
мішені.Приводится описание ускорителя электронов ИЛУ-10 на энергию 5 МэВ мощностью 50 кВт, специально разработанного для таких комплексов. Для упрощения конструкции конвейерной системы подачи обрабатываемой продукции в зону облучения используется выпускное устройство с поворотом пучка на 90 градусов и последующей конвертацией электронного пучка в гамма-излучение на вертикально расположенной мишени
Study of Decays
We report on a study of decays using
29.1 fb of annihilation data recorded at the
resonance with the Belle detector at the KEKB storage ring. Making no
assumptions about the intermediate mechanism, the branching fractions for
and are
determined to be and respectively. An analysis of candidates yields to the first observation of the color-suppressed
hadronic decay with the branching fraction . We measure the ratio of branching fractions
= 1.6 0.8.Comment: 13 pages, LaTex, 4 figures, submitted to Phys. Lett.
Measurements of Branching Fractions and Decay Amplitudes in B-> J/\psi K^* decays
The branching fractions and the decay amplitudes of B -> J/psi K^* decays are
measured in a 29.4/fb data sample collected with the Belle detector at the KEKB
electron-positron collider. The decay amplitudes of helicity states of the
J/psi K^* system are determined from the full angular distribution of the final
state particles in the transversity basis. The branching fractions are measured
to be (1.29\pm0.05\pm0.13) \times 10^{-3} for neutral mesons and
(1.28\pm0.07\pm0.14) \times 10^{-3} for charged mesons. The measured
longitudinal and transverse (perpendicular to the transversity plane)
amplitudes are |A_0|^2 = 0.62\pm0.02\pm0.03 and |A_{\perp}|^2 =
0.19\pm0.02\pm0.03, respectively. The value of |A_{\perp}|^2 shows that the CP
even component dominates in the B^0 \to J/\psi K^{*0}(K_S\pi^0) decay.Comment: 17 pages, 3 figures, 5 tables, to appear in Phys. Lett.
Work status of 5 MeV 300 kW electron accelerator
Design work has been completed for the accelerating structure of high-power electron accelerator with 5 MeV,
300 kW, 176 MHz parameters. The structure is being produced in BINP workshop. The paper presents the design of
the accelerating structure which consists of a chain of coaxial cavities, and block diagram of experimental
workbench. Structure of the main accelerator blocks and their degree of fabrication are viewed.Закончены проектные работы по ускоряющей структуре мощного электронного ускорителя 5 МэВ,
300 кВт, 176 МГц и ведется ее изготовление в опытном производстве Института. Дается описание
конструкции ускоряющей структуры, состоящей из цепочки связанных коаксиальных резонаторов.
Приводится блок-схема испытательного стенда, рассматривается устройство отдельных узлов ускорителя и
состояние их готовности.Закінчено проектні роботи із прискорювальної структури потужного електронного прискорювача 5 МеВ,
300 кВт, 176 МГц і ведеться її виготовлення в дослідному виробництві інституту. Дається опис конструкції
прискорювальної структури, що складається з ланцюжка зв'язаних коаксіальних резонаторів. Приводиться
блок-схема іспитового стенда, розглядається будова окремих вузлів прискорювача і стан їх готовності
Measurement of the inclusive semileptonic branching fraction of B mesons and |Vcb|
We present a measurement of the electron spectrum from inclusive semileptonic
{\it B} decay, using 5.1 fb of data collected with the
Belle detector. A high-momentum lepton tag was used to separate the
semileptonic {\it B} decay electrons from secondary decay electrons. We
obtained the branching fraction, , with minimal model dependence.
From this measurement, we derive a value for the Cabibbo-Kobayashi-Maskawa
matrix element .Comment: 16 pages, 3 figures, 3 table
A Measurement of the Branching Fraction for the Inclusive B --> X(s) gamma Decays with the Belle Detector
We have measured the branching fraction of the inclusive radiative B meson
decay B --> X(s) gamma to be Br(B->X(s)gamma)=(3.36 +/- 0.53(stat) +/-
0.42(sys) +0.50-0.54(th)) x 10^{-4}.
The result is based on a sample of 6.07 x 10^6 BBbar events collected at the
Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric e^+e^-
storage ring.Comment: 14 pages, 6 Postsript figures, uses elsart.cl
The first observation of decay
We present the first measurement of tau-decays to hadronic final states with
a -meson. This is based on 401.4 fb of data accumulated at the
Belle experiment. The branching ratio obtained is .Comment: 10 pages, 5 figures, ICHEP2006 contribution pape
Search for Lepton Flavor Violating tau- Decays Including with a K0s Meson
We have searched for the lepton flavor violating decays \tau^-\to \ell^-\ks
(), using a data sample of 281 fb collected with the
Belle detector at the KEKB asymmetric-energy collider. No evidence for
a signal was found in either of the decay modes, and we set the following upper
limits for the branching fractions: {\cal{B}}(\tau^-\to e^-\ks) < 5.6\times
10^{-8} and {\cal{B}}(\tau^-\to \mu^-\ks) < 4.9\times 10^{-8} at the 90%
confidence level. These results improve the previously published limits set by
the CLEO collaboration by factors of 16 and 19, respectively.Comment: 9 pages, 3figures, submitted to Phys.Lett.
Measurement of Branching Fractions for at Belle
We have measured the branching fractions for the exclusive decay modes using a data sample collected by the
Belle detector at the KEKB asymmetric-energy collider. The measured
branching fractions for , ,
and decay modes are
, ,
and ,
respectively, where the first error is statistical and the second error is
systematic. We do not observe statistically significant signals for the decay modes and set upper limits at the 90% confidence
level. We also study the helicity distribution for decay
mode and show that the longitudinal polarization component is dominant. {{\it
Keywords:} {-meson, Charmonium, Branching Fractions, Polarization}} {{\it
PACS:} 13.25.Hw, 11.30.Er}Comment: 21 pages, 5 figures, 3 tables. Submitted to PL
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