393,855 research outputs found
Cytological study of Allium cepa and Allium sativum
The large number of species in the Allium genus has necessitated comparative analysis of related species which has always been used in many cases to describe patterns and directions of chromosomal evolution within a group. This study was carried out to cytologically analyse two species of Allium- Allium cepa and Allium sativum. All the four stages of cell division were observed in both species, although well spread metaphase chromosomes could not be observed in A. sativum which limited the extent to which we could cytologically evaluate the species. Allium cepa in this study show cell with a complement of sixteen chromosomes. A total chromosome length of 577.5 µm was observed in the best c-metaphase spread with the longest chromosome being 43.4µm and the shortest 27.9 µm. Further studies are still required in the karyotype analysis of A. sativum from Nigeri
CGC/saturation approach for soft interactions at high energy: a two channel model
In this paper we continue the development of a model for strong interactions
at high energy, based on two ingredients: CGC/saturation approach and the BFKL
Pomeron. In our approach, the unknown mechanism of confinement of quarks and
gluons, is characterized by several numerical parameters, which are extracted
from the experimental data. We demonstrate that the two channel model,
successfully describes the experimental data, including both the value of the
elastic slope and the energy behavior of the single diffraction cross section.
We show that the disagreement with experimental data of our previous single
channel eikonal model [6] stems from the simplified approach used for the
hadron structure, and is not related to our principal theoretical input, based
on the CGC/saturation approach.Comment: 20 pp., 20 figure in eps file
CGC/saturation approach for soft interactions at high energy: inclusive production
In this letter we demonstrate that our dipole model is successful in
describing the inclusive production within the same framework as diffractive
physics. We believe that this achievement stems from the fact that our approach
incorporates the positive features of the Reggeon approach and CGC/saturation
effective theory, for high energy QCComment: 8 pages, 6 figures in.eps file
Long range rapidity correlations in soft interaction at high energies
In this paper we take the next step (following the successful description of
inclusive hadron production) in describing the structure of the bias events
without the aid of Monte Carlo codes. Two new results are presented :(i) a
method for calculating the two particle correlation functions in the
BFKLPomeron calculus in zero transverse dimension;and (ii) an estimation of the
values of these correlations in a model of soft interactions. Comparison with
the multiplicity data at the LHC is given.Comment: 23pp. 13 figures in eps.file
CGC/saturation approach for high energy soft interactions: `soft' Pomeron structure and in hadron and nucleus collisions from Bose-Einstein correlation
In the framework of our model of soft interactions at high energy based on
CGC/saturation approach,we show that Bose-Einstein correlations of identical
gluons lead to large values of . We demonstrate how three dimensional
scales of high energy interactions: hadron radius, typical size of the wave
function in diffractive production of small masses (size of the constituent
quark), and the saturation momentum, influence the values of BE correlations,
and in particular, the values of . Our calculation shows that the
structure of the `dressed' Pomeron leads to values of which are close to
experimental values for proton-proton scattering, 20\% smaller than the
observed values for proton-lead collisions, and close to lead-lead collisions
for 0-10\% centrality. Bearing this result in mind, we conclude that it is
premature to consider, that the appearance of long range rapidity azimuthal
correlations are due only to the hydrodynamical behaviour of the quark-gluon
plasma.Comment: 26pp. 25 figures in .eps file
A model for strong interactions at high energy based on the CGC/saturation approach
We present our first attempt to develop a model for soft interactions at high
energy, based on the BFKL Pomeron and the CGC/saturation approach. We construct
an eikonal-type model, whose opacity is determined by the exchange of the
dressed BFKL Pomeron. The Green's function of the Pomeron is calculated in the
framework of the CGC/saturation approach. Using five parameters we achieve a
good description of the experimental data at high energies (
). The model results in different behaviour for the single
and double diffraction cross sections at high energies. The single diffraction
cross section reaches a saturated value (about 10 mb) at high energies, while
the double diffraction cross section continues growing slowlyComment: 21 pp. 16 figures in eps file
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