Detectors for Nuclear Physics

Abstract

Progress in nuclear physics is driven by the experimental observation that requires state of the art detectors to measure various kinematic properties, such as energy, momentum, position etc. of the particles produced in a nuclear reaction. Advances in detector technology has enabled nuclear physicists to measure these quantities with better precision, and the reduced cost of the detection system has helped to have larger detection systems (array of detectors) to measure the rare processes with greater sensitivity. Several detection systems have been designed, developed and built in India over last few decades and are being used by the physicists. In this article, I will focus on such developments of detection systems at Variable Energy Cyclotron Centre (VECC), Kolkata. Introduction:It is a privilege to present this review on the detector developments for nuclear physics research at Variable Energy Cyclotron Centre (VECC), in this particular conference, that celebrates the centenary year of Bose Institute which happens to be the first inter disciplinary research institute in India, founded by Sir Jagadish Chandra Bose. He was one of the legendry Indian experimentalists who used to build his own instruments from the scratch for his research. The components of the instruments that he built (e.g; 60 GHz microwave apparatus [1] was quite innovative but remained pretty simple, that really attract and inspire us when we try to build our detectors in our laboratory. Scope of detection in fundamental nuclear physics:One of the fundamental questions that we deal in Nuclear Physics is, how do the nucleons work together to form complex nuclei. This branch of Nuclear Physics is often referred as Nuclear Structure. On the other hand, many of these nuclei are needed to make them react with target nuclei in order to understand the rearrangement of the nucleons inside nuclei that helps us to know the macroscopic or bulk properties of the nuclei. The interaction between two complex nuclei is broadly studied under the section called Nuclear Reaction. In general, the study of nuclear structure and nuclear reaction constitutes the low energy nuclear physics research. However there is another branch; the study of the constituents of nucleons, i.e. quarks and gluons and their interactions. This study requires very high energy to break the nucleons and this constitutes the high energy nuclear physics.Let us have a look at the evolution of nuclear physics with energy (as shown in Fig 1). The change over from one zone to other is not sharp, rather having consid-

Development of THGEM-based Detectors for Nuclear Fission Studies

“…It was also found that the increase of anode signal, as well as cathode signal, increase the position signal significantly (Figure 3). The rise time of anode signal is ∼ 7 nSec while that of position signal is ∼ 8 − 13 nSec This result is in agreement with the previous experimental data [5]. Similar signal calculation shows that due to the low gain value of the THGEM-Multi Wire hybrid detector the signal amplitude is lower than that of MWPC (Figure 4).…”

“…• MWPC: It consists of five wire planes which include one anode (A), two sense wire planes (X,Y), two cathode (C) planes (Figure 1(a)) [5]. The wires of X and Y planes have diameter 50 µm with a pitch of 2 mm and are fixed perpendicular to each other.…”

“…Although wire-based detectors have been extensively used in low-energy physics experiments [5], they have some severe drawbacks. The most critical is the use of fragile anode wires having a diameter of only 10 µm and, therefore, severely reducing the portability of these detectors.…”

Development of Micro-Pattern Gaseous Detectors for Nuclear Reaction Studies

“…The rise time of anode signal is ~ 7 nSec while that of position signal is ~ 8 -13 nSec. This result is in agreement with the previous experimental data [7].…”

“…These detectors can be made to cover large surface area, if needed. This type of detector with a thin-walled windows have been fabricated in the Variable Energy Cyclotron Centre (VECC) and used successfully to study different fission reactions in which very good time (0.7 nSec) and position (1.5 mm) resolutions were achieved [7].…”