The Measurement of the Gluon Spin Polarization in Nucleon

In these three years，we concentrated to the preparation of the COMPASS experiment at CERN in Geneva.The first subject is the construction of the polarized target。In order to prepare the polarized target，several individual part must be completed。Our group has shared the construction of the superconductive magnet and the construction of microwave system。The magnet was ordered to Oxford Instr.Co.LTD.The first stage of the research was the design of the magnet.Second stage was the preparation of the cryogenic system，magnet support system，microwave system etc.We contributed the design of the microwave system and the cryogenic system.The control system of the magnet and cryogenic systems has been designed。The check of the system will be performed after the arrival of the magnet.For the construction of the scintillating fiber tracker，we made several test experiments on the pulse height and the time resolution in 1997-1999 at CERN and INS.In1999，we have assembled a prototype o…More f a tracker with a diameter of 0.5 mm scintillating fiber，and measured the time resolution to the real muon beam in a beam intensity of 10 I D 18 I D 1 ppp.We found that the tracker gave a best time resolution ofσ~350ps。This prototype is composed of 7layers of fibers.It is found that the improvement of the voltage divider giving additional voltage from outside to the last4dinodes of the photo-tube(16ch.H1658made by Hamamatsu Photonics)was quite effective the higher trigger rate experiment。We have contributed to COMPASS in one more field，that is，off-line analysis in the experiment。Before the data taking by the experiment，many programs have to be prepared，for example，monitors of the equipment，the graphic display of those data，display of data histograms，event pattern recognition，data base arrangement，simulation for reaction and detectors etc.Our group members contributed to the production of the program of the histogram formation，data base arrangements.The Grant-in-Aid(International Collaboration Research)supported the abmentove mented of the histogram formation，the scarrangements.the Grant-in-Aid

In these three years, we concentrated to the preparation of the COMPASS experiment at CERN in Geneva.The first subject is the construction of the polarized target. In order to prepare the polarized target, several individual part must be completed. Our group has shared the construction of the superconductive magnet and the construction of microwave system. The magnet was ordered to Oxford Instr. Co. LTD. The first stage of the research was the design of the magnet. Second stage was the preparation of the cryogenic system, magnet support system, microwave system etc. We contributed the design of the microwave system and the cryogenic system. The control system of the magnet and cryogenic systems has been designed. The check of the system will be performed after the arrival of the magnet.For the construction of the scintillating fiber tracker, we made several test experiments on the pulse height and the time resolution in 1997-1999 at CERN and INS.In 1999, we have assembled a prototype o … More f a tracker with a diameter of 0.5 mm scintillating fiber, and measured the time resolution to the real muon beam in a beam intensity of 10ィイD18ィエD1 ppp. We found that the tracker gave a best time resolution of σ〜350 ps. This prototype is composed of 7 layers of fibers. It is found that the improvement of the voltage divider giving additional voltage from outside to the last 4 dinodes of the photo-tube (16ch. H1658 made by Hamamatsu Photonics) was quite effective the higher trigger rate experiment. We have contributed to COMPASS in one more field, that is, off-line analysis in the experiment. Before the data taking by the experiment, many programs have to be prepared, for example, monitors of the equipment, the graphic display of those data, display of data histograms, event pattern recognition, data base arrangement, simulation for reaction and detectors etc. Our group members contributed to the production of the program of the histogram formation, data base arrangements.The Grant-in-Aid (International Collaboration Research) supported the above mentioned research activities and some consumable materials which are needed for the development of the polarized target and the scintillating fiber tracker etc. Less