[en] It is possible to generate an infinite number of conserved quantities and the most general solution in an arbitrary background with the help of the Darboux-Backlun transformation and an expansion of the Lax eigenfunction in the eigenvalue parameter. Use is not made of the Riccati form of the Lax equation which is used in the usual derivation of the conserved quantities. It is shown that for zero seed solution one retrieves the usual one-soliton solution

No abstract available

[en] The Compressed Baryonic matter (CBM) experiment plans to explore the phase space diagram of strongly interacting matter at finite baryochemical potential. Several detectors will be commissioned at the experiment like silicon tracking station (STS), Time of Flight (TOF) etc. A muon beam along with three trigger scintillation detectors were also part of the experiment to undertake efficiency and gain estimates. For the first time, we successfully operated two modules with full acceptance with a Common Readout Interface (CRI) based data acquisition (DAQ) subsystem. In this document we present the preliminary results for GEM module from the afore mentioned experiment. From the preliminary test results we observe that the detector is now proven to work in full relation is showing a single sharp peak which is similar to expectations. The branch current fluctuations are also noted to have reduced as compared to previous experiments. In summary, the preliminary tests hint that the detector is working well within the operational parameters

[en] Gas Electron Multiplier (GEM) belongs to the family of micro-pattern gaseous detectors, primarily used to detect and track charge particles. For neutron detection, a converter material can be embedded to GEM detectors. The selection and suitability of converter material depends on both its neutron interaction cross section value and ability to discriminate against the inherent background gamma radiation. The experimental results of several irradiation tests carried out with neutron source ²⁵²Cf are presented. The aim of the experiment is to detect neutrons using GEM detectors and measure the efficiency. In this regard, Californium-252 source was chosen as the neutron source. With 3% branching ratio for neutrons, the Gamma abundance is much more than neutrons from the source, Pb shield has to be placed to screen the gammas. Simulations were carried out to estimate the expected detector counts for different thicknesses of Pb. Boron Coating on drift plate of GEM detector is undergoing and an experiment for neutron detection using Boron coated GEM detector is planned

[en] The PARIS (Photon Array for the studies with Radioactive Ion and Stable beams) detector, a γ-ray calorimeter, is under development by an international collaboration for γ-ray measurement with low intensity radioactive ion beams (RIBs) at upcoming RIB facilities. The detector comprises more than 200 PARIS phoswich elements. Each phoswich element is made of a front 2″ cubic LaBr₃(Ce) crystal optically coupled to a 2″ × 2″ 6″ NaI(Tl) crystal at the back. Both the crystals are read by a single photomultiplier tube (PMT- Hamamatsu R7723-100) coupled at the rare end. The widely different decay time of the two crystals (16 (250) ns for LaBr₃ (NaI)) allows the separation of LaBr₃ and NaI signals employing pulse shape discrimination. The advantage of this cost-optimized design is that the timing information could be extracted from the front LaBr₃ which has better timing resolution compared to NaI and addback technique could be used to extract the full energy deposition for an event. Further, using these phoswich elements, low energy γ-rays can be measured in a background of high energy γ-rays. Experiments with two PARIS clusters (3 × 3 matrix of phoswich elements) have demonstrated the capability of the desired phoswich design

[en] The CBM experiment at FAIR is being designed to explore the QCD phase diagram of high baryon density matter using high-energy fixed target nucleus-nucleus collisions. Muon Chamber (MUCH) is the detector to be used in CBM to detect low momentum muons, originating from the decay of low-mass vector mesons. The final design of the muon detector system consists of 6 hadron absorber layers and 18 Gaseous tracking chambers located in triplets behind each absorber slab. VECC is in process of building and testing the Muon Chambers (MUCH) and related readout electronics for the first two stations. MUCH uses Front End Electronics (FEE) board where the desired operating temperature range is 25-30 °C. Temperature going above this limit will drift the biasing scheme and further increase may lead to damage of FEE boards. We have developed a microcontroller based automated temperature controller system at VECC using multiple temperature sensors (DS18B20) on a One Wire Bus

[en] The Jacobi shape transition, an abrupt change of shape from non-collective oblate to collective triaxial or prolate shape above a critical spin (J_C), has been predicted to appear in atomic nucleus due to its liquid drop nature at high excitation energy. The onset of Jacobi shape transition has been observed in a few light nuclei through the Giant Dipole Resonance (GDR) decay spectrum, characterized by a narrow low energy component ∼ 10 MeV arising due to the Coriolis splitting. Measurement of the GDR spectrum from a self-conjugate α-cluster nucleus ²⁸Si, populated in the reaction ¹⁶O + ¹²C at < J> ∼ 21 ħ, which is higher than J_C = 17 ħ, is carried out

[en] An ab initio calculation has been carried out to investigate the biaxial strain ( - 10.71% < ε < 9.13%) effect on elastic, electronic and optical properties of CuAlO₂. All the elastic constants (c₁₁, c₁₂, c₁₃, c₃₃) except c₄₄ decrease (increase) during tensile (compressive) strain. The band gap is found to decrease in the presence of tensile as well as compressive strain. The relative decrease of the band gap is asymmetric with respect to the sign of the strain. Significant differences between the parallel and perpendicular components of the dielectric constant and the optical properties have been observed due to anisotropic crystal structure. It is further noticed that these properties are easily tunable by strain. Importantly, the collective oscillation of the valence electrons has been identified for light polarized perpendicular to the c-axis. From calculations, it is clear that the tensile strain can enhance the hole mobility as well as the transparency of CuAlO₂. (paper)

[en] To study the GDR parameters and their variation with temperature and angular momentum, the reactions "1"2C+"1"1"2Sn and "1"2C+"1"2"4Sn are studied at 5.3 and 4.3 MeV/nucleon, respectively. The beam energies were chosen to produce the compound nuclei at same excitation energies (E"∗-E_r_o_t ∼49 MeV), allowing to explore the isospin effect on GDR width. The preliminary results of the measurement are presented here

[en] The CBM experiment is designed to investigate the properties of dense nuclear matter in nucleus-nucleus collision at an unprecedented interaction rate up to 10 MHz. CBM will consist of 4 stations of Muon- Chambers (MuCh) sandwiched between absorber layers and each station will consist of 3 layers of gaseous detectors. The two modules have been participating in the data taking since last 4 years and have undergone some hardware modifications as we approach towards the final version. In the earlier version of the drift PCB, some surface discharges were observed in the HV layout section, which resulted into link instability of the MuCh-XYTER readout electronics. In this report, we present the design modification of the drift PCB, fabrication of the detector and lab test results of the same. We prepared a cosmic muon coincidence setup and measured the efficiency of 96% corresponding to summed voltage of 1125 Volts. After a satisfactory lab test this module was installed in the mCBM cave