The cross section for e(+)e(-)-->pi(+)pi(-)J/psi between 3.8 and 5.5 GeV/c(2) is measured using a 548 fb(-1) data sample collected on or near the Upsilon(4S) resonance with the Belle detector at ...KEKB. A peak near 4.25 GeV/c(2), corresponding to the so called Y(4260), is observed. In addition, there is another cluster of events at around 4.05 GeV/c(2). A fit using two interfering Breit-Wigner shapes describes the data better than one that uses only the Y(4260), especially for the lower-mass side of the 4.25 GeV enhancement.
We examine the branch structure of radial diffusion-limited aggregation (DLA) clusters for evidence of multifractality. The lacunarity of DLA clusters is measured and the generalized dimensions D(q) ...of their mass distribution is estimated using the sandbox method. We find that the global n-fold symmetry of the aggregates can induce anomalous scaling behavior into these measurements. However, negating the effects of this symmetry, standard scaling is recovered.
The cross section for e+ e- --> pi+ pi- psi(2S) between threshold and sqrts=5.5 GeV is measured using 673 fb(-1) of data on and off the Upsilon(4S) resonance collected with the Belle detector at ...KEKB. Two resonant structures are observed in the pi+ pi- psi(2S) invariant-mass distribution, one at 4361 +/- 9 +/- 9 MeV/c2 with a width of 74 +/- 15 +/- 10 MeV/c2, and another at 4664 +/- 11 +/- 5 MeV/c2 with a width of 48 +/- 15 +/- 3 MeV/c2, if the mass spectrum is parametrized with the coherent sum of two Breit-Wigner functions. These values do not match those of any of the known charmonium states.
The IEEE 1451 set of standards defines an architectural model for interfacing multiple ‘smart transducers’ in a distributed environment, which can gate to a fieldbus or local area network. However, ...the IEEE 1451 standards do not support strict real-time message scheduling within the transducer cluster environment. This work proposes that a time-triggered control network, TTCAN (time-triggered controller area network), be employed as the multiplexed interface for smart transducers. Such a development would allow a deterministic control message scheduling matrix to be defined so that all transducer message scheduling can be guaranteed. The proposal effectively changes the IEEE 1451 architecture from an event-driven system to a true time-driven system. The existing set of IEEE 1451 standards are briefly reviewed and the new TTCAN control network is described. A complete prototype design implementation of the proposed system is presented. The prototype system demonstrates that the concept is feasible and workable. Time-triggered networks are synchronous control networks where the scheduling of control messages is progressed, based strictly on the passage of time, based on the network's sense of global time. Such time-triggered networks are being developed primarily for the automotive industry to support reliable scheduling for safety-critical control systems such as brake-by-wire and steer-by-wire systems. This work shows that it is now possible to apply such time-triggered paradigms to general transducer interfacing environments.
We report the first observation of e;{+}e;{-}-->Upsilon(1S)pi;{+}pi;{-}, Upsilon(2S)pi;{+}pi;{-}, and first evidence for e;{+}e;{-}-->Upsilon(3S)pi;{+}pi;{-}, Upsilon(1S)K+K-, near the peak of the ...Upsilon(5S) resonance at sqrts approximately 10.87 GeV. The results are based on a data sample of 21.7 fb;{-1} collected with the Belle detector at the KEKB e;{+}e;{-} collider. Attributing the signals to the Upsilon(5S) resonance, the partial widths Gamma(Upsilon(5S)-->Upsilon(1S)pi;{+}pi;{-})=0.59+/-0.04(stat)+/-0.09(syst) MeV and Gamma(Upsilon(5S)-->Upsilon(2S)pi;{+}pi;{-})=0.85+/-0.07(stat)+/-0.16(syst) MeV are obtained from the observed cross sections. These values exceed by more than 2 orders of magnitude the previously measured partial widths for dipion transitions between lower Upsilon resonances.
Vertex detector for super Belle experiment Kawasaki, T.; Barbero, M.; Friedl, M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
05/2006, Volume:
560, Issue:
1
Journal Article
Peer reviewed
Using a high resolution silicon vertex detector and a large number of B meson decays, the Belle experiment has succeeded in measuring time-dependent CP asymmetry with high precision. To continue the ...search for physics beyond the standard model, an upgrade of the KEKB collider to a luminosity of
10
35
–
36
cm
-
2
s
-
1
is proposed. Such a luminosity upgrade will also require an upgraded (“Super”) Belle experiment. Discussions have started on the conceptual design for the silicon vertexing upgrade of this detector. Since the momenta of particles is not high in B factory operating at the
ϒ
(
4
S
)
resonance, it is important to avoid high occupancy while keeping the material budget low. A fast data acquisition system and radiation hardness are also required. In this report, the conceptual design of a vertex detector for the Super Belle experiment is shown. The status of R&D topics is also reported.
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