Alexandru Jipa | University of Bucharest (original) (raw)
Papers by Alexandru Jipa
Journal of Archaeological Science, 2002
Abstract. An analysis of the intermittency in peripheral He-Li collisions at 4.5 A GeV/c is perfo... more Abstract. An analysis of the intermittency in peripheral He-Li collisions at 4.5 A GeV/c is performed to search for a limit in the collision geometry to evidence anomal states in nuclear matter at different densities and temperatures. The Bialas-Peschanski formalism has been ...
Cyberbullying as an Internet adapted form of the traditional bullying can seriously impact on the... more Cyberbullying as an Internet adapted form of the traditional bullying can seriously impact on the health and the personality of those involved in an e-learning activity. The cyberbullying can affect all types of educational resources used in an e-learning course.
In Romania, e-learning as a teacher training activity is at the beginning and has o lot of oppone... more In Romania, e-learning as a teacher training activity is at the beginning and has o lot of opponents, due to technical, economical, social and ethical problems associated with it. Some of these problems are the subject of this paper.
We present some results obtained by applying the chaos theory on the numerical study of one three... more We present some results obtained by applying the chaos theory on the numerical study of one threedimensional, relativistic, many-body quark system. The asymptotic freedom property is introduced by employing a harmonic term in the bi-particle potential. In this context, we used also the outcome of a semiclassical study, applied to the quark constituents of nucleons. Depending on the initial temperature parameter, the system can evolve toward an oscillating or an expansion regime. It is important to notice also a transition region, characterized by a partial fragmentation (higher degree of order). This effect can be observed near the critical temperature and is related to the partial overcoming of the potential barrier (corresponding to the farthest particles from the system). The "degree of fragmentation" is defined on the Shannon entropy basis and using the graphs theory. For analyzing the expansion tendency of one relativistic many-body system, we employed also the "virial coefficient".
In nucleus- nucleus collisions at high energies the collision geometry is very important. The par... more In nucleus- nucleus collisions at high energies the collision geometry is very important. The participant- spectator picture is used to o btain information on the c ollision dynamics from the experimental results. In this paper a method to find the contributions of the two regions to the multiplicity distributions of the negative and charged particles is discussed. The ordinary moments
Romanian Reports in Physics
In our work we have analysed the ability of light nuclei ((2)H,(3)H,(3)He,(4)He) formation in sel... more In our work we have analysed the ability of light nuclei ((2)H,(3)H,(3)He,(4)He) formation in self-conjugate 4n-nuclei interactions. We have use the FLUKA simulation code with RQMD-2.4 implementation model to describe nucleus-nucleus collision at 100 MeV/nucleon, intermediate energy. For this purpose, a direct reaction system (12)C+(40)Ca and an inverse reaction system (40)Ca+(12)C is chose. Interesting results and conclusions are obtained on competition emission of light nuclei, reaction channel of light nuclei from QP and how the kinematics of reaction influenced the light nuclei formation.
Romanian Reports in Physics
The main objective of this work is the analysis of the alpha structures that can go out from the ... more The main objective of this work is the analysis of the alpha structures that can go out from the quasi-projectile systems in nuclear collisions at intermediate energies (similar to 100 A MeV). In the modelation of the mechanisms of such structures we used different simulation codes, as FLUKA and Geant4. Another objective in our analysis was to check the properties of alpha structures in comparison with properties of alpha particles that are expected to be created by nuclear Bose-Einstein condensation mechanisms. Interesting results are obtained for (12)C+(40)Ca nuclear system.
With the advent of intense accelerator-based sources of neutrinos and the demand of neutrino osci... more With the advent of intense accelerator-based sources of neutrinos and the demand of neutrino oscillation experiments to more precisely determine signal and background rates in their detectors has precipitated a resurged interest for neutrino interactions in the few-GeV energy range. Such measurements have not been updated for decades, having first been measured in bubble and spark chamber experiments. New measurements are sorely needed and yield important constraints for present and future neutrino oscillation experiments operating in this energy range. In the present contribution, we studied neutrino interactions in the few-GeV energy range. We used GENIE, a new neutrino Monte Carlo generator, to generate events and compute the cross sections for neutrino-nucleus interactions. Events are generated for particular user-defined situation: neutrinos scattered off a fix nuclear target (40 Ar nucleus). We present the obtained results, after we analyzed the event samples, on relevant dist...
The muons represent the EAS penetrating component and carry information about the mass and the en... more The muons represent the EAS penetrating component and carry information about the mass and the energy of the primary cosmic particle, under the influence of the Earth magnetic field. The study of the high energy muon flux brings new informations regarding the muon multiplicities and the hadronic interaction models. The high energy muons represent, also, the main contribution at the natural radiation dose in underground which is important for low background measurements. A new experimental facility for studies of high energy muons is proposed as underground facility in a salt mine in Slanic Prahova, Romania. Simulation studies using CORSIKA and MUSIC codes estimate the expected muon rate at aprox. 600 mwe (meter water equivalent). The energy cut off is estimated to be 150–200 GeV. A new mobile laboratory which permit measurements at surface and in underground is in construction. For the future a muon experiment (MUON-UG) is planned to get installed in the mine to study hadronic inter...
Romanian Journal of Physics
TL measurements, independently performed on 114 rock salt samples collected at a depth of between... more TL measurements, independently performed on 114 rock salt samples collected at a depth of between 130 and 210 m from the Cantacuzino mine located in the Slanic-Prahova halite deposits and on Fimel TM GR200A TL dosimeters, showed a monotonous decrease of the dose rate with depth in good correlation with the muon flux. The latter was calculated on the bases of experimental determinations on the salt deposits surface as well as at 210 m depth. Concurrently, the gamma spectra of salt samples collected from the same locations showed a quasi-absence of the natural radioactive elements. This, which in correlation with TL data and muon flux vertical profile points towards muon as the main depositor of energy in salt, makes the Slanic-Prahova rock-sat deposits a sui generis natural muon detector.
Procedia - Social and Behavioral Sciences, 2010
The basic communication skills are improved by the Information and Communication Technology (ICT)... more The basic communication skills are improved by the Information and Communication Technology (ICT), which has a great impact in our society and also in teaching and learning of the scientific concepts. In the present work we intent to present our SWOT analysis referring to implementation of the Intel® Teach Program, in Romanian education.
Il Nuovo Cimento A, 1994
ABSTRACT
Il Nuovo Cimento A, 1993
Summary The physical information offered by the participants in some nucleus-nucleus collisions ... more Summary The physical information offered by the participants in some nucleus-nucleus collisions at 4.5 GeV/c per nucleon are discussed in this paper. The connections of the participants with the multiplicity, the mass and atomic numbers of the two colliding nuclei, the temperature of the overlapping region between nuclei at the emission of the negative pions are considered. The experiments have been
Procedia - Social and Behavioral Sciences, 2011
The utilization of the e-learning environments for teacher training programs is at the beginning ... more The utilization of the e-learning environments for teacher training programs is at the beginning in the Romanian system for teacher continuous formation. Also, the rules for approving this kind of formation program are not approved yet, due the ongoing modification to The Law of ...
Procedia - Social and Behavioral Sciences, 2011
Some interesting e-learners’ needs were observed during the study of the data provided by the cou... more Some interesting e-learners’ needs were observed during the study of the data provided by the course developed by the Transfer of Innovation project: “T&T – Telework and Training: Work at distance to Teach at Distance”. The trainees were teachers from Pre University and VET schools and students from POLITEHNICA University of Bucharest. The age of the trainees and their educational
Procedia - Social and Behavioral Sciences, 2011
Our students have to understand that Physics is not only about memorizing and calculating. If the... more Our students have to understand that Physics is not only about memorizing and calculating. If the cognitive load theory is applied when teachers are developing their lesson projects, the questions and the evaluation forms, then they are able to better monitor their students' understanding. The interactive Smart Board is an excellent way of learning, being an instrument used by teachers for both teaching lessons as well as for grading students. The cognitive load theory can be applied in teaching Physics more easily when we are using the Smart Notebook 10 software because the material in a lesson can be presented in a more interactive way. The present paper's purpose is to present the way in which teachers can promote an interactive learning and stimulate students' creative potential, by using the interactive whiteboard and the cognitive load theory.
Romanian Reports in Physics
There are fundamental questions in particle and astroparticle physics that are still open. New ex... more There are fundamental questions in particle and astroparticle physics that are still open. New experimental facilities as sources of particles and detection systems are needed to solve them. An incompletely understood sector of particle physics is the low energy neutrino interactions. The scope of this contribution is to investigate the possibility to measure some Standard Model parameters and search for new physics with low energy neutrinos and to suggest the possibility to obtain neutrinos with well determined energies. This physics and some experimental aspects could be applied in the next generation of underground detectors with very large volume , in particular in the LAGUNA project. Arguments of interest for some physics aspects and measurable quantities using neutrinos with low energy are presented. Some possibilities to obtain intense neutrino beams with controlled energy are subsequently discussed.
Procedia - Social and Behavioral Sciences, 2010
ABSTRACT The utilization of the interactive whiteboard is a challenge for Romanian teachers. The ... more ABSTRACT The utilization of the interactive whiteboard is a challenge for Romanian teachers. The education methods involving this device can vary because they depend on the components involved in this process: the teacher, the students, the computer, as basic tool, and software, including applications developed for education in different programming languages. The results of a preliminary study involving 54 Romanian teachers about the experience referring to this subject are presented.
Journal of Archaeological Science, 2002
Abstract. An analysis of the intermittency in peripheral He-Li collisions at 4.5 A GeV/c is perfo... more Abstract. An analysis of the intermittency in peripheral He-Li collisions at 4.5 A GeV/c is performed to search for a limit in the collision geometry to evidence anomal states in nuclear matter at different densities and temperatures. The Bialas-Peschanski formalism has been ...
Cyberbullying as an Internet adapted form of the traditional bullying can seriously impact on the... more Cyberbullying as an Internet adapted form of the traditional bullying can seriously impact on the health and the personality of those involved in an e-learning activity. The cyberbullying can affect all types of educational resources used in an e-learning course.
In Romania, e-learning as a teacher training activity is at the beginning and has o lot of oppone... more In Romania, e-learning as a teacher training activity is at the beginning and has o lot of opponents, due to technical, economical, social and ethical problems associated with it. Some of these problems are the subject of this paper.
We present some results obtained by applying the chaos theory on the numerical study of one three... more We present some results obtained by applying the chaos theory on the numerical study of one threedimensional, relativistic, many-body quark system. The asymptotic freedom property is introduced by employing a harmonic term in the bi-particle potential. In this context, we used also the outcome of a semiclassical study, applied to the quark constituents of nucleons. Depending on the initial temperature parameter, the system can evolve toward an oscillating or an expansion regime. It is important to notice also a transition region, characterized by a partial fragmentation (higher degree of order). This effect can be observed near the critical temperature and is related to the partial overcoming of the potential barrier (corresponding to the farthest particles from the system). The "degree of fragmentation" is defined on the Shannon entropy basis and using the graphs theory. For analyzing the expansion tendency of one relativistic many-body system, we employed also the "virial coefficient".
In nucleus- nucleus collisions at high energies the collision geometry is very important. The par... more In nucleus- nucleus collisions at high energies the collision geometry is very important. The participant- spectator picture is used to o btain information on the c ollision dynamics from the experimental results. In this paper a method to find the contributions of the two regions to the multiplicity distributions of the negative and charged particles is discussed. The ordinary moments
Romanian Reports in Physics
In our work we have analysed the ability of light nuclei ((2)H,(3)H,(3)He,(4)He) formation in sel... more In our work we have analysed the ability of light nuclei ((2)H,(3)H,(3)He,(4)He) formation in self-conjugate 4n-nuclei interactions. We have use the FLUKA simulation code with RQMD-2.4 implementation model to describe nucleus-nucleus collision at 100 MeV/nucleon, intermediate energy. For this purpose, a direct reaction system (12)C+(40)Ca and an inverse reaction system (40)Ca+(12)C is chose. Interesting results and conclusions are obtained on competition emission of light nuclei, reaction channel of light nuclei from QP and how the kinematics of reaction influenced the light nuclei formation.
Romanian Reports in Physics
The main objective of this work is the analysis of the alpha structures that can go out from the ... more The main objective of this work is the analysis of the alpha structures that can go out from the quasi-projectile systems in nuclear collisions at intermediate energies (similar to 100 A MeV). In the modelation of the mechanisms of such structures we used different simulation codes, as FLUKA and Geant4. Another objective in our analysis was to check the properties of alpha structures in comparison with properties of alpha particles that are expected to be created by nuclear Bose-Einstein condensation mechanisms. Interesting results are obtained for (12)C+(40)Ca nuclear system.
With the advent of intense accelerator-based sources of neutrinos and the demand of neutrino osci... more With the advent of intense accelerator-based sources of neutrinos and the demand of neutrino oscillation experiments to more precisely determine signal and background rates in their detectors has precipitated a resurged interest for neutrino interactions in the few-GeV energy range. Such measurements have not been updated for decades, having first been measured in bubble and spark chamber experiments. New measurements are sorely needed and yield important constraints for present and future neutrino oscillation experiments operating in this energy range. In the present contribution, we studied neutrino interactions in the few-GeV energy range. We used GENIE, a new neutrino Monte Carlo generator, to generate events and compute the cross sections for neutrino-nucleus interactions. Events are generated for particular user-defined situation: neutrinos scattered off a fix nuclear target (40 Ar nucleus). We present the obtained results, after we analyzed the event samples, on relevant dist...
The muons represent the EAS penetrating component and carry information about the mass and the en... more The muons represent the EAS penetrating component and carry information about the mass and the energy of the primary cosmic particle, under the influence of the Earth magnetic field. The study of the high energy muon flux brings new informations regarding the muon multiplicities and the hadronic interaction models. The high energy muons represent, also, the main contribution at the natural radiation dose in underground which is important for low background measurements. A new experimental facility for studies of high energy muons is proposed as underground facility in a salt mine in Slanic Prahova, Romania. Simulation studies using CORSIKA and MUSIC codes estimate the expected muon rate at aprox. 600 mwe (meter water equivalent). The energy cut off is estimated to be 150–200 GeV. A new mobile laboratory which permit measurements at surface and in underground is in construction. For the future a muon experiment (MUON-UG) is planned to get installed in the mine to study hadronic inter...
Romanian Journal of Physics
TL measurements, independently performed on 114 rock salt samples collected at a depth of between... more TL measurements, independently performed on 114 rock salt samples collected at a depth of between 130 and 210 m from the Cantacuzino mine located in the Slanic-Prahova halite deposits and on Fimel TM GR200A TL dosimeters, showed a monotonous decrease of the dose rate with depth in good correlation with the muon flux. The latter was calculated on the bases of experimental determinations on the salt deposits surface as well as at 210 m depth. Concurrently, the gamma spectra of salt samples collected from the same locations showed a quasi-absence of the natural radioactive elements. This, which in correlation with TL data and muon flux vertical profile points towards muon as the main depositor of energy in salt, makes the Slanic-Prahova rock-sat deposits a sui generis natural muon detector.
Procedia - Social and Behavioral Sciences, 2010
The basic communication skills are improved by the Information and Communication Technology (ICT)... more The basic communication skills are improved by the Information and Communication Technology (ICT), which has a great impact in our society and also in teaching and learning of the scientific concepts. In the present work we intent to present our SWOT analysis referring to implementation of the Intel® Teach Program, in Romanian education.
Il Nuovo Cimento A, 1994
ABSTRACT
Il Nuovo Cimento A, 1993
Summary The physical information offered by the participants in some nucleus-nucleus collisions ... more Summary The physical information offered by the participants in some nucleus-nucleus collisions at 4.5 GeV/c per nucleon are discussed in this paper. The connections of the participants with the multiplicity, the mass and atomic numbers of the two colliding nuclei, the temperature of the overlapping region between nuclei at the emission of the negative pions are considered. The experiments have been
Procedia - Social and Behavioral Sciences, 2011
The utilization of the e-learning environments for teacher training programs is at the beginning ... more The utilization of the e-learning environments for teacher training programs is at the beginning in the Romanian system for teacher continuous formation. Also, the rules for approving this kind of formation program are not approved yet, due the ongoing modification to The Law of ...
Procedia - Social and Behavioral Sciences, 2011
Some interesting e-learners’ needs were observed during the study of the data provided by the cou... more Some interesting e-learners’ needs were observed during the study of the data provided by the course developed by the Transfer of Innovation project: “T&T – Telework and Training: Work at distance to Teach at Distance”. The trainees were teachers from Pre University and VET schools and students from POLITEHNICA University of Bucharest. The age of the trainees and their educational
Procedia - Social and Behavioral Sciences, 2011
Our students have to understand that Physics is not only about memorizing and calculating. If the... more Our students have to understand that Physics is not only about memorizing and calculating. If the cognitive load theory is applied when teachers are developing their lesson projects, the questions and the evaluation forms, then they are able to better monitor their students' understanding. The interactive Smart Board is an excellent way of learning, being an instrument used by teachers for both teaching lessons as well as for grading students. The cognitive load theory can be applied in teaching Physics more easily when we are using the Smart Notebook 10 software because the material in a lesson can be presented in a more interactive way. The present paper's purpose is to present the way in which teachers can promote an interactive learning and stimulate students' creative potential, by using the interactive whiteboard and the cognitive load theory.
Romanian Reports in Physics
There are fundamental questions in particle and astroparticle physics that are still open. New ex... more There are fundamental questions in particle and astroparticle physics that are still open. New experimental facilities as sources of particles and detection systems are needed to solve them. An incompletely understood sector of particle physics is the low energy neutrino interactions. The scope of this contribution is to investigate the possibility to measure some Standard Model parameters and search for new physics with low energy neutrinos and to suggest the possibility to obtain neutrinos with well determined energies. This physics and some experimental aspects could be applied in the next generation of underground detectors with very large volume , in particular in the LAGUNA project. Arguments of interest for some physics aspects and measurable quantities using neutrinos with low energy are presented. Some possibilities to obtain intense neutrino beams with controlled energy are subsequently discussed.
Procedia - Social and Behavioral Sciences, 2010
ABSTRACT The utilization of the interactive whiteboard is a challenge for Romanian teachers. The ... more ABSTRACT The utilization of the interactive whiteboard is a challenge for Romanian teachers. The education methods involving this device can vary because they depend on the components involved in this process: the teacher, the students, the computer, as basic tool, and software, including applications developed for education in different programming languages. The results of a preliminary study involving 54 Romanian teachers about the experience referring to this subject are presented.