The project implementation schedule
Phase no. 1
Responsible: Dr. T. Preda
Deadline: 30.04.2016
Phase title: “Experimental research and Monte Carlo simulations of the Si and GaAs sensors with potential to be used in space sciences”
Abstract: Object Oriented software in C++ has been developed for processing a big volume of experimental data which were collected by electromagnetic calorimeter prototypes composed of tungsten plates of 3.5 mm thickness as absorbers and thin silicon or gallium arsenide pad sensors as sensitive elements (pads have a few millimeters in size). They were exposed in 2 GeV electron collimated beams of the DESY II accelerator from DESY-Hamburg and also in combined beams of 5 GeV electrons, muons and hadrons of the Proton Synchrotron (PS) accelerator of CERN-Geneva. The prototypes constructions which includes pad sensors, tungsten plates with high flatness, high precision mechanical framework to support sensors and absorbers, ASIC front-end electronics based on IBM CMOS 130 nm, multichannel ADC ASIC, Data Concentrator, etc. were developed in the framework of the FCAL international collaboration for developing forward compact electromagnetic to determine with high precision the luminosity at the potentially future linear electron-positron colliders, ILC-Japan and/or CLIC-CERN. Additional infrastructures for making the measurements at accelerators, as high precision telescopes with pixel or strip planes necessary for reconstructing the tracks of the incident beam, Cerenkov detectors, trigger and data acquisition system, etc. were financed by AIDA program (Advanced European Infrastructures for Detectors and Accelerators).
We developed algorithms for signal analysis taking into account the entire event data which contain registrations of every sensor, every electronic chip and every channel. The developed software allows us to: (a) “homogenize” the data in an iterative way; (b) extract efficiently the common noise (CMN) for every chip, using in the calculations all 8 channels, instead of 4, how are used by other groups, and therefore the electronic noises decreased with about 60%. We developed also an original method to separate electrons from muons which allowed us to make a very good energetic calibration, but also a good analysis of the Landau-type spectra of the energy loss fluctuations by ionization obtained at the passing of muons by silicon sensors and also to study with precision the longitudinal development of the electromagnetic shower.
Monte Carlo simulation programs in C++, which include entire set-up, were developed. They use the GENT4 classes for particle trancing and particle interaction with matter. The simulation results for the fluctuation of the energy loss in thin silicon and gallium arsenide sensors are in good agreement with our experimental results.
Phase no. 2
Responsible: Dr. Gina Isar
Deadline: 15.06.2016
Title: Studies and advanced techniques for ultra high energy cosmic rays measured on ground
Since more than a century of cosmic ray discovery, the multidisciplinary field of astroparticle physics and high energies has highly developed at the international level. Cosmic rays are either measured directly in space with detectors placed aboard satellites, or indirectly in the Earth’s atmosphere, on ground, under ground/water/ice etc. Indirect measurement are done through cosmic rays induced air showers in the Earth’s atmosphere at the interaction of the primary cosmic ray particle with atmospheric nuclei.
The Pierre Auger Observatory is the world’s largest cosmic ray experiment, which covers a surface of 3000 km square in the Argentinian pampas. It is a super-hibrid experiment employing complementary techniques like Cerenkov water tanks, fluorescence telescopes and radio antennas.
Since November 2015, Auger entered its new phase of uprade, which will continue the data taking with upgraded detectors and increased statistics for 10 more years. Romania became full Auger member in 2014, the Institute of Space Science – ISS being one of the four national member institutes. The objectives of this project comes in support to the ISS activities in frame of Auger, with expected results on: 1) simulations and analysis of ultra high energy cosmic rays events, 2) rising the computing support of the GRID ISS infrastructure in frame of Auger VO, 3) a test bench release at the ISS for the Auger SDEU – Surface Detectors Upgraded Electronics task in order to test and validate the Upgraded Unified Boards.
Phase no.3 – First part
Responsible: Dr. E. Firu
Deadline: 15.07.2016
Title: “Electromagnetic dissociation in nuclear emulsion at energies below 5 GeV” –
Abstract: The nuclear emulsion is one of the longest detector udes in the field of nuclear physics. Nuclear emulsion is a solid detector which store information left by particles passing through the detector medium. After develop, the interactions in nuclear emulsion are studed using visual methods. At this stage of the project we analayse interaction of 3He nuclei in emulsion at 1GeV energy. The irradiations were done at Dubna – Nuclotron take into account a collaboration between ISS and JINR. In order to fulfill the goals of this task we investigated on the first place the selection criteria for ED interactions (ED- electromagnetic dissociation) and the clusterization types in nuclear emulsion. After that the charge topology of the 3He nucleus, mean free path and its cross section was presented. We observed that the experimental value that we observed for the mean free path and the total cross section for nuclear interaction is very close to the theoretical value and that the mean free path for nuclear interaction decreases with the projectile charge in agreement with the data obtained in other experiments.
Phase no.3- Second part
Responsible: Dr. A. Neagu
Deadline: 15.07.2016
Title: “Electromagnetic dissociation in nuclear emulsion at energies below 5 GeV”
Abstract: In the second stage of the project task we investigated the polar angle for particles of charge one in the process of electromagnetic dissociation of the 3He nucleus in nuclear emulsion, the angle between particles of charge one emitted in the electromagnetic dissociation of 3He and transverse momentum for relativistic particles. The experimental data were compared with the data simulated for the same processes and obtained very interesting and striking results that need to be seriously analyzed on a much better statistics. The understanding of these facts could also require to use other simulation codes that imply other physical models that could lead to an agreement of the experimental and simulated data, in order to reveal new process that should be taken into account.
Phase no. 5
Responsible: PhD M. I. Cherciu
Deadline: 15.09.2016
Title: “Collective modes studies of far away stability nuclei”
Abstract:
The nuclear collective modes of the exotic nuclei play a key role for understanding of properties of nucleonic many body system, of elements nucleosynthesis in Universe and of properties of symmetric nuclear matter. Through the international facility FAIR-GSI, Germany, the studies of far away stability nuclei will be touch within experimental area R3B (Reactions with Relativistic Radioactive Beams). An important role for understanding/description of nuclear processes is played by Monte Carlo codes. Thus, we have evaluated the collective mode behavior of simulation code FLUKA for stable nuclei but also for exotic nuclei. The simulation code Fluka is a Monte-Carlo code for particle transport and interactions with matter, covering a wide range of applications: from accelerator shielding, calorimetry, activation, dosimetry, detector design, cosmic rays, radiotherapy etc. Fluka is writen in FORTRAN and efficiently combine: interaction cross section data base with theoretical models and/or parameterised fits of existing experimental data. The results of interest can be obtained by subroutine modification, of FLUKA simulation code, as same as experiment itself requirements, write them to dedicate ROOT files and event by event analysis of the data with different physics quantities. The results of the studies show an acceptable agreement with the stable nuclei (124Sn, 18O) reactions but a bad agreement with the exotic nuclei (14B, 132Sn), suggesting that the FLUKA data base or theoretical models for such nuclei require to be improved.
Phase no. 9
Responsible: Dr. Marian Traian Ghenescu
Deadline: 09.12.2016
Title: “The influence of ionizing radiation on physical properties of A2B6 multi-junction photovoltaic structures”
Abstract: The multi-junction solar cells (MJ) are the photovoltaic structures with two or more pn junctions, arrange in a specific order taking into account of their thickness and the band gap values, respectively. The space environment consists of different charged particles (87% are protons, 12% alpha particles and heavy ions) with large energetic spectrum depending on the orbit. In order to estimate the mission lifetime for such electronic systems it is necessary to study the performances of the electronic devices exposed to these cosmic rays, especially less-shielded devices. The Monte-Carlo simulations were used to calculate the stopping power for proton and alpha particles in multi-junction solar cells, especially in the low energy region. The total NIEL dose deposited in the ZnS/CdS/CdTe structure for the same space environment is almost the same like deposited dose in the Si or GaAs photovoltaic structures. Taking into account these results, our conclusion is the photovoltaic structures based on A2B6 compounds have a good potential for space applications.