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141.
Dipak Ghosh Madhumita Lahiri Argha Deb Susobhan Das Krishnadas Purkait Biswanath Biswas Jayanta Roy Choudhury Rini Chatterjee Abdul Kayum Jafry 《Zeitschrift fur Physik C Particles and Fields》1996,71(1):243-249
The scaled factorial moments and the multifractal moments have been investigated in differentη-intervals to study the dynamical fluctuation of pions produced in 200 AGeV32S-Ag/Br interaction. In order to investigate the detail characteristics of intermittency behaviour, theF-moments are extracted up to the eighth order of moments in differentM-intervals. The analysis indicates a non-thermal phase transition and different regime of particle production during the hadronisation process. 相似文献
142.
Final-state interaction and screening have a great influence on $q\bar q$ production cross sections, which are important quantities in many problems in quark-gluon plasma physics. They lead to an enhancement of the cross section for a $q\bar q$ color-singlet state and a suppression for a color-octet state. The effects are large near the production threshold. The presence of screening gives rise to resonances for $q\bar q$ production just above the threshold at specific plasma temperatures. These resonances, especially $c\bar c$ and $b\bar b$ resonances, may be utilized to search for the quark-gluon plasma by studying the temperature dependence of heavy-quark pair production just above the threshold. 相似文献
143.
T. T. Kam S. S. Chatterjee K. E. Heusler 《Applied Physics A: Materials Science & Processing》1984,35(4):219-226
Etch pit densities on iron (110) surfaces in sulphuric acid grow linearly with the interfacial hydrogen activity in excess of a critical activity. The hydrogen activity is approximately proportional to the square root of the cathodic current density. At constant cathodic current density the etch pit density increases with temperature and decreases with external stress. Dislocations at which the excess etch pits form penetrate into the iron at a rate proportional to the hydrogen activity and the square root of time. Effects of prior hydrogen deposition on the shape of etch pits are seen at depths greater than the penetration depth of hydrogen generated dislocations. Changes of etch pit shape similar to those produced by hydrogen are also found when external stress is applied.The results are compared to Prussin's theory in which the assumption is made that stresses accompanying diffusion of an impurity are fully relieved by plastic deformation and formation of dislocations for stresses exceeding a critical stress. While some of the predictions of the theory are met by the experiments, the dislocations penetrate into the iron much slower than diffusion of hydrogen, since dislocations cannot move fast enough, i.e. stresses are not fully relieved. 相似文献
144.
145.
The total (p, n) reaction cross section for48Ca has been measured as a function of proton energy in the energy range 1.885 to 5.100 MeV with an overall resolution of ∼
2 keV and in ∼ 5 keV energy steps. The fluctutions in fine resolution data have been analysed to determine the average coherence
width 〈Γ〉. The excitation function averaged over large energy intervals has been analyzed in terms of the optical model. The
isobaric analogue resonances atE
p
∼ 1.95 and 4 MeV have been shape-analyzed to extract the proton partial width and the spectroscopic factorS
n
. A comparison of the gross structures observed in ∼ 55 keV averaged excitation function with the predictions of Izumo’s partial
equilibrium model has also been made. 相似文献
146.
147.
J.M. Chatterjee S. Basu-Roy S.S. Ghugre S. Chattopadhyay R.P. Singh G.O. Rodrigues R.K. Chattopadhyay R.K. Bhowmik 《The European Physical Journal A - Hadrons and Nuclei》1998,1(1):55-59
A search for new isomers of nanosecond lifetimes were carried out in 153Eu via the 150Nd(7Li,xnγ) reaction. The single particle angular momentum alignment and dynamical moment of inertia estimated from the experimental
data indicate a configuration change at rotational energy ħω∼ 0.30 MeV. A decrease of B(E2) values is also observed at the
same frequency. An isomeric level is identified at an excitation energy of 3100 keV (Jπ=35/2−) which corresponds to this frequency. The lifetime of the level is found to be 8.6 ± 1.3 nanosecond.
Received: 22 April 1997 / Revised version: 26 September 1997 相似文献
148.
We present a method for stabilizing ferromagnetism in Mn doped ZnO. We find that Mn doped ZnO show anti-ferromagnetic order in the absence of additional carriers. When Mn doped ZnO is co-doped with C atom at O sites ferromagnetic state gets stabilized. The C doping creates holes which leads to stabilization of ferromagnetic state via hole mediated double exchange mechanism. 相似文献
149.
150.