4,719 research outputs found
Pi N sigma-term and chiral-odd twist-3 distribution function e(x) of the nucleon in the chiral quark soliton model
The isosinglet combination of the chiral-odd twist-3 distribution function
of the nucleon has outstanding properties that its first moment
is proportional to the well-known sigma-term and that it contains a
-function singularity at . These two features are inseparably
connected in that the above sum rule would be violated, if there is no such a
singularity in . Very recently, we found that the physical
origin of this -function singularity can be traced back to the
long-range quark-quark correlation of scalar type, which signals the
spontaneous chiral symmetry breaking of the QCD vacuum. The main purpose of the
present paper is to give complete theoretical predictions for the chiral-odd
twist-3 distribution function of each flavor on the basis of the
chiral quark soliton model, without recourse to the derivative expansion type
approximation. These theoretical predictions are then compared with the
empirical information extracted from the CLAS data of the semi-inclusive DIS
processes by assuming the Collins mechanism only. A good agreement with the
CLAS data is indicative of a sizable violation of the sigma-term sum
rule, or equivalently, the existence of a -function singularity in
.Comment: 35 pages, 10 figure
Belle II iTOP Optics: Design, Construction and Performance
The imaging-Time-of-Propogation (iTOP) counter is a new type of ring-imaging
Cherenkov counter developed for particle identification at the Belle II
experiment. It consists of 16 modules arranged azimuthally around the beam
line. Each module consists of one mirror, one prism and two quartz bar
radiators. Here we describe the design, acceptance test, alignment, gluing and
assembly of the optical components. All iTOP modules have been successfully
assembled and installed in the Belle II detector by the middle of 2016. After
installation, laser and cosmic ray data have been taken to test the performance
of the modules. First results from these tests are presented.Comment: Proceedings of TIPP 2017, May 22 - 26, Beijing, China, 2017;
University of Cincinnati preprint UCHEP-17-07. arXiv admin note: text overlap
with arXiv:1709.0993
Mechanical Behavior of Cohesive Soil under Repeated Loading
A new triaxial apparatus which can control the stress condition automatically in a constant mean principal stress under repeated loading was developed, Mechanical behavior of cohesive soils under repeated loading was investigated. Excess pore water pressure generated in loading cycles was measured and the experimental results were interpreted in terms of effective stress by using elasto-plastic models
Indication of intrinsic spin Hall effect in 4d and 5d transition metals
We have investigated spin Hall effects in 4 and 5 transition metals,
Nb, Ta, Mo, Pd and Pt, by incorporating the spin absorption method in the
lateral spin valve structure; where large spin current preferably relaxes into
the transition metals, exhibiting strong spin-orbit interactions. Thereby
nonlocal spin valve measurements enable us to evaluate their spin Hall
conductivities. The sign of the spin Hall conductivity changes systematically
depending on the number of electrons. This tendency is in good agreement
with the recent theoretical calculation based on the intrinsic spin Hall
effect.Comment: 5 pages, 4 figure
Jet-fluid string formation and decay in high-energy heavy-ion collisions
We propose a new hadronization mechanism, jet-fluid string (JFS) formation
and decay, to understand observables in intermediate to high- regions
comprehensively. In the JFS model, hard partons produced in jet lose their
energy in traversing the QGP fluid, which is described by fully
three-dimensional hydrodynamic simulations. When a jet parton escapes from the
QGP fluid, it picks up a partner parton from a fluid and forms a color singlet
string, then it decays to hadrons. We find that high- values in JFS
are about two times larger than in the independent fragmentation model.Comment: 6 pages, 2 figures; Proceeding for poster sessions at Quark Matter
2006, Shanghai, China, 14-20 November 2006; to appear in Int. J. of Mod.
Phys.
Search for a Ridge Structure Origin with Shower Broadening and Jet Quenching
We investigate the role of jet and shower parton broadening by the strong
colour field in the - correlation of high
particles. When anisotropic momentum broadening () is
given to jet and shower partons in the initial stage, a ridge-like structure is
found to appear in the two hadron correlation. The ratio of the peak to the
pedestal yield is overestimated.Comment: Talk given at 20th Int. Conf. on Ultra-Relativistic Nucleus-Nucleus
Collisions, Jaipur, India, Feb.4-10, 200
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