Journal of Physics G-nuclear and Particle Physics, 2009
Based on the quantum molecular dynamics (QMD) picture, we calculate the energy and mass dependenc... more Based on the quantum molecular dynamics (QMD) picture, we calculate the energy and mass dependence of fragment production. For the present study, we simulated the reactions of $^{20}Ne+^{20}Ne$, $^{40}Ar+^{45}Sc$, $^{58}Ni+^{58}Ni$, $^{86}Kr+^{93}Nb$,$^{129}Xe+^{124}Sn$ and $^{197}Au+^{197}Au$ at central geometry. Our findings clearly show a linear mass dependence for the peak center-of-mass energy at which the maximal IMF production occurs. Such linear dependence for peak center-of-mass energy on the system size has also been observed in recent experimental studies. We also predict a similar behavior for the multiplicities of different kinds of fragments. Experiments are called for to verify this prediction.
The Asian Pacific Association for the Study of the Liver (APASL) set up a Working Party on Portal... more The Asian Pacific Association for the Study of the Liver (APASL) set up a Working Party on Portal Hypertension in 2002, with a mandate to develop consensus guidelines on various clinical aspects of portal hypertension relevant to disease patterns and clinical practice in the Asia-Pacific region. Variceal bleeding is a consequence of portal hypertension, which, in turn, is the major complication of liver cirrhosis. Primary prophylaxis to prevent the first bleed from varices is one of the most important strategies for reducing the mortality in cirrhotic patients. Experts predominantly from the Asia-Pacific region were requested to identify the different aspects of primary prophylaxis and develop the consensus guidelines. The APASL Working Party on Portal Hypertension evaluated the various therapies that have been used for the prevention of first variceal bleeding. A 2-day meeting was held on January 12 and 13, 2007, at New Delhi, India, to discuss and finalize the consensus statements. Only those statements that were unanimously approved by the experts were accepted. These statements were circulated to all the experts and were subsequently presented at the annual conference of the APASL at Kyoto, Japan, in March 2007.
Journal of Physics G-nuclear and Particle Physics, 2010
We here study fragmentation using \emph{simulated annealing clusterization algorithm} (SACA) with... more We here study fragmentation using \emph{simulated annealing clusterization algorithm} (SACA) with binding energy at a microscopic level. In an earlier version, a constant binding energy (4 MeV/nucleon) was used. We improve this binding energy criterion by calculating the binding energy of different clusters using modified Bethe-Weizs\"{a}cker mass (BWM) formula. We also compare our calculations with experimental data of ALADiN group. Nearly no effect is visible of this modification.
The entropy production in medium energy heavy-ion collisions is analyzed in terms of ratio of deu... more The entropy production in medium energy heavy-ion collisions is analyzed in terms of ratio of deuteronlike to protonlike clusters ( d/p) using quantum molecular dynamics (QMD) model. The yield ratios of deuteronlike-to-protonlike clusters calculated as a function of participant proton multiplicity closely agree with experimental trends. Our model predictions indicate that full thermodynamical equilibrium may not be there even for the central geometry. The apparent entropy extracted from the yield ratios of deuteronlike-to-protonlike clusters, however, reflects the universality characteristics i.e. it is governed by the volume of reaction independent of the target-projectile combination. Our calculations for apparent entropy produced in central collisions of Ca + Ca and Nb + Nb at different bombarding energies are in good agreement with 4 π Plastic Ball data.
We report the consequences of implementing momentum dependent interactions (MDI) on multifragment... more We report the consequences of implementing momentum dependent interactions (MDI) on multifragmentation in heavy-ion reactions over entire collision geometry. The evolution of a single cold nucleus using static soft equation of state and soft momentum dependent equation of state demonstrates that inclusion of momentum dependence increases the emission of free nucleons. However, no heavier fragments are emitted artificially. The calculations performed within the framework of quantum molecular dynamics approach suggest that MDI strongly influence the system size dependence of fragment production. A comparison with ALADiN experimental data justifies the use of momentum dependent interactions in heavy-ion collisions.
Journal of Physics G-nuclear and Particle Physics, 2009
Based on the quantum molecular dynamics (QMD) picture, we calculate the energy and mass dependenc... more Based on the quantum molecular dynamics (QMD) picture, we calculate the energy and mass dependence of fragment production. For the present study, we simulated the reactions of $^{20}Ne+^{20}Ne$, $^{40}Ar+^{45}Sc$, $^{58}Ni+^{58}Ni$, $^{86}Kr+^{93}Nb$,$^{129}Xe+^{124}Sn$ and $^{197}Au+^{197}Au$ at central geometry. Our findings clearly show a linear mass dependence for the peak center-of-mass energy at which the maximal IMF production occurs. Such linear dependence for peak center-of-mass energy on the system size has also been observed in recent experimental studies. We also predict a similar behavior for the multiplicities of different kinds of fragments. Experiments are called for to verify this prediction.
The Asian Pacific Association for the Study of the Liver (APASL) set up a Working Party on Portal... more The Asian Pacific Association for the Study of the Liver (APASL) set up a Working Party on Portal Hypertension in 2002, with a mandate to develop consensus guidelines on various clinical aspects of portal hypertension relevant to disease patterns and clinical practice in the Asia-Pacific region. Variceal bleeding is a consequence of portal hypertension, which, in turn, is the major complication of liver cirrhosis. Primary prophylaxis to prevent the first bleed from varices is one of the most important strategies for reducing the mortality in cirrhotic patients. Experts predominantly from the Asia-Pacific region were requested to identify the different aspects of primary prophylaxis and develop the consensus guidelines. The APASL Working Party on Portal Hypertension evaluated the various therapies that have been used for the prevention of first variceal bleeding. A 2-day meeting was held on January 12 and 13, 2007, at New Delhi, India, to discuss and finalize the consensus statements. Only those statements that were unanimously approved by the experts were accepted. These statements were circulated to all the experts and were subsequently presented at the annual conference of the APASL at Kyoto, Japan, in March 2007.
Journal of Physics G-nuclear and Particle Physics, 2010
We here study fragmentation using \emph{simulated annealing clusterization algorithm} (SACA) with... more We here study fragmentation using \emph{simulated annealing clusterization algorithm} (SACA) with binding energy at a microscopic level. In an earlier version, a constant binding energy (4 MeV/nucleon) was used. We improve this binding energy criterion by calculating the binding energy of different clusters using modified Bethe-Weizs\"{a}cker mass (BWM) formula. We also compare our calculations with experimental data of ALADiN group. Nearly no effect is visible of this modification.
The entropy production in medium energy heavy-ion collisions is analyzed in terms of ratio of deu... more The entropy production in medium energy heavy-ion collisions is analyzed in terms of ratio of deuteronlike to protonlike clusters ( d/p) using quantum molecular dynamics (QMD) model. The yield ratios of deuteronlike-to-protonlike clusters calculated as a function of participant proton multiplicity closely agree with experimental trends. Our model predictions indicate that full thermodynamical equilibrium may not be there even for the central geometry. The apparent entropy extracted from the yield ratios of deuteronlike-to-protonlike clusters, however, reflects the universality characteristics i.e. it is governed by the volume of reaction independent of the target-projectile combination. Our calculations for apparent entropy produced in central collisions of Ca + Ca and Nb + Nb at different bombarding energies are in good agreement with 4 π Plastic Ball data.
We report the consequences of implementing momentum dependent interactions (MDI) on multifragment... more We report the consequences of implementing momentum dependent interactions (MDI) on multifragmentation in heavy-ion reactions over entire collision geometry. The evolution of a single cold nucleus using static soft equation of state and soft momentum dependent equation of state demonstrates that inclusion of momentum dependence increases the emission of free nucleons. However, no heavier fragments are emitted artificially. The calculations performed within the framework of quantum molecular dynamics approach suggest that MDI strongly influence the system size dependence of fragment production. A comparison with ALADiN experimental data justifies the use of momentum dependent interactions in heavy-ion collisions.
Uploads
Papers by Yogesh Puri