Speaker
Dr
I-Yang Lee
(Lawrence Berkeley National Laboratory)
Description
The gamma-ray energy tracking array GRETINA uses 28 Ge crystals, each with 36 segments, to cover ¼ of the 4pi solid angle. The gamma ray tracking technique requires detailed digital pulse shape information from each of the segments. These pulses are analyzed to determine the energy, time, and three-dimensional positions of all gamma-ray interactions. This information is then utilized, together with the characteristics of Compton scattering and pair-production processes, to track the scattering sequences of the gamma rays. Tracking arrays will give higher efficiency, better peak-to-total ratio and much higher position resolution, and thus increases the detection sensitivity by factors of several hundred compared to current arrays used in nuclear physics research. Particularly, the capability of reconstructing the position of the interaction with millimeters resolution is needed to fully exploit the physics opportunities at current and next generation radioactive beam facilities.
GRETINA construction at the 88-Inch Cyclotron at LBNL is completed in March 2011. Currently, Extensive engineering runs were carried out using radioactive sources, and beams from the Cyclotron. The data obtained will be used to optimize its performance. Then scientific runs will start in September 2011. GRETINA will provide world leading opportunities to advance studies in nuclear structure, nuclear reactions, and fundamental symmetries.
Primary author
Dr
I-Yang Lee
(Lawrence Berkeley National Laboratory)
