| Time Projection Chamber(TPC)is a high precise tracking detector.It can provide both 3D spatial coordinates and particle tracks to get d E/dx information.With High ability of particle identifying,it has been widely used in a lot of nuclei physics experiments.To study hadron physics and nuclear structure,IMP cooperates with Wigner research center in Hungary to develop a new generation detector,that is the TPC prototype based on GEM.It provides a basis for future study.Time Proj ection Chamber(TPC)based on GEM readout was designed and tested successfully.GEM-TPC is widely used for researches of particle identification and hadron physics due to its simple working principle,high position and time resolution,and the ability to provide three-dimensional tracks of particles and so on.We discuss from the following three aspects,the first part is the introduction of structure and principle of GEM-TPC,the readout electronics system is elaborated in this part.The second part is the construction of experimental instruments and the experimental process in CSR.The third part is the analysis of the detector performance.It gives the drift time of each running,the drift speed of TPC,particle track reconstruction and the relation between GEM voltage and signal value.We find test results is the same as those in Hungary.It indicates that the detector can work stably in the case of beam flow.The accomplishment of this article will be improtant to optimize the design and performance of GEM-TPC.The design of readout plate also provides a new idea to improve the position resolution of the detector.In addition,the detector can also be used in the experiment of emission of hypernucleu bremsstrahlung.So bremsstrahlung theory is also studied as follows:We propose a new way to study the properties of hypernucleis via analysis of bremsstrahlung photons in nuclear reactions with hypernuclei.A new model of the bremsstrahlung emission which accompanies interactions between ? particles and hypernuclei is constructed,where a new formalism for the magnetic momenta of nucleons and hyperon inside hypernucleus and many-body problem are added.By analyzing the bremsstrahlung spectrum of ? decay of normal nuclei 210Po and hypernuclei ?211Po,we find that emission for the hypernucleus ?211Po is larger than for normal nucleus 210Po,although difference between these spectra is small.As demonstration of such a property,we show that the spectra for the hypernuclei 107?Te and 109?Te are essentially larger than the spectra for the normal nuclei 106Te and 108Te.Such a difference is explained by additional contribution of emission to the full bremsstrahlung,which is formed by magnetic moment of hyperon inside hypernucleus.Moreover,in order to explore whether the model of the bremsstrahlung emission has the same applicability for heavy and light hypernuclei,we calculate bremsstrahlung of photons emitted in a decay of 9Be?9B?10?Be and 10?B.We find that the role of magnetic moment of hyperon inside light hypernuclei in formation of the bremsstrahlung emission is greater than that in heavy hypernuclei.We propose a way how to find hypernuclei by confirming the effect of the magnetic moment of the hyperon in emission of bremsstrahlung photons during ? decay.It opens possibility of new experimental study of properties of hypernuclei via bremsstrahlung study. |
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