1,138 research outputs found
On the linearly polarized gluon distributions in the color dipole model
We show that the linearly polarized gluon distributions appear in the color
dipole model as we derive the full cross sections of the DIS dijet production
and the Drell-Yan dijet ( jet correlation) process. Together with the
normal Weizs\"acker-Williams gluon distribution, the linearly polarized one
will contribute to the DIS dijet production cross section as the coefficient of
the term in the correlation limit. We also derive the
exact results for the cross section of the Drell-Yan dijet process, and find
that the linearly polarized dipole gluon distribution which is identical to the
normal dipole gluon distribution involves in the cross section. The results
obtained in this paper agree with the previous transverse momentum dependent
factorization study. We further derive the small- evolution of these
linearly polarized gluon distributions and find that they rise as gets
small at high energy.Comment: 10 pages,v2 with minor revisio
Characterization and Localization of Cyclin B3 Transcript in Both Oocyte and Spermatocyte of the Rainbow Trout (Oncorhynchus Mykiss)
B-type cyclins are regulatory subunits with distinct roles in the cell cycle. To date, at least three subtypes of B-type cyclins (B1, B2, and B3) have been identified in vertebrates. Previously, we reported the characterization and expression profiles of cyclin B1 and B2 during gametogenesis in the rainbow trout (Oncorhynchus mykiss). In this paper, we isolated another subtype of cyclin B, cyclin B3 (CB3), from a cDNA library of the rainbow trout oocyte. The full-length CB3 cDNA (2,093 bp) has an open reading frame (1,248 bp) that encodes a protein of 416 amino acid residues. The CB3 transcript was widely distributed in all the examined tissues, namely, eye, gill, spleen, brain, heart, kidney, stomach, skin, muscle, and, especially, gonad. Northern blot analysis indicated only one form of the CB3 transcript in the testis and ovary. In situ hybridization revealed that, in contrast to cyclin B1 and B2 transcripts, CB3 transcripts were localized in the oocytes, spermatocytes, and spermatogonia. These findings strongly suggest that CB3 plays a role not only as a mitotic cyclin in spermatogonial proliferation during early spermatogenesis but also during meiotic maturation of the spermatocyte and oocyte in the rainbow trout
Empirical metallicity-dependent calibrations of effective temperature against colours for dwarfs and giants based on interferometric data
We present empirical metallicity-dependent calibrations of effective
temperature against colours for dwarfs of luminosity classes IV and V and for
giants of luminosity classes II and III, based on a collection from the
literature of about two hundred nearby stars with direct effective temperature
measurements of better than 2.5 per cent. The calibrations are valid for an
effective temperature range 3,100 - 10,000 K for dwarfs of spectral types M5 to
A0 and 3,100 - 5,700 K for giants of spectral types K5 to G5. A total of
twenty-one colours for dwarfs and eighteen colours for giants of bands of four
photometric systems, i.e. the Johnson (), the Cousins
(), the Sloan Digital Sky Survey (SDSS, ) and the Two
Micron All Sky Survey (2MASS, ), have been calibrated. Restricted
by the metallicity range of the current sample, the calibrations are mainly
applicable for disk stars ([Fe/H]). The normalized percentage
residuals of the calibrations are typically 2.0 and 1.5 per cent for dwarfs and
giants, respectively. Some systematic discrepancies at various levels are found
between the current scales and those available in the literature (e.g. those
based on the infrared flux method IRFM or spectroscopy). Based on the current
calibrations, we have re-determined the colours of the Sun. We have also
investigated the systematic errors in effective temperatures yielded by the
current on-going large scale low- to intermediate-resolution stellar
spectroscopic surveys. We show that the calibration of colour ()
presented in the current work provides an invaluable tool for the estimation of
stellar effective temperature for those on-going or upcoming surveys.Comment: 28 pages, 19 figures, 8 tables, accepted for publication in MNRA
Solving for Dispersivity in Field Dispersion Test of Unsteady Flow in Mixing Flow Field: Mass Transport Modeling
AbstractA combined groundwater flow and mass transport model was constructed to simulate the migration of contaminants and to obtain dispersion parameters from a field dispersion test in unsteady flow in mixing flow field in groundwater. Aquifer parameters were obtained by a pumping test. Tracer tests were carried out in order to characterize the characteristics of groundwater flow and to determine the velocity of the pollutant diffusion process from the source to the pumping well. Groundwater head and velocity were analyzed in the groundwater flow model and the total dissolved solids (TDS) concentration was computed in the mass transport model. The observed drawdown and the observed TDS concentration were found to respectively match closely with the computed drawdown and TDS concentration
Edge Charge Asymmetry in Top Pair Production at the LHC
In this brief report, we propose a new definition of charge asymmetry in top
pair production at the LHC, namely the edge charge asymmetry (ECA). ECA
utilizes the information of drifting direction only for single top (or
anti-top) with hadronically decay. Therefore ECA can be free from the
uncertainty arising from the missing neutrino in the event
reconstruction. Moreover rapidity of top (or anti-top) is required to be
greater than a critical value in order to suppress the symmetric
events mainly due to the gluon-gluon fusion process. In this paper
ECA is calculated up to next-to-leading order QCD in the standard model and the
choice of the optimal is investigated.Comment: 10 pages, 6 figure
- …