Design of Wide-energy-range Neutron Calorimeter for Nuclear Collisions in the Korea Rare-isotope Accelerator
Design of Wide-energy-range Neutron Calorimeter for Nuclear Collisions in the Korea Rare-isotope Accelerator
- 주제(키워드) Neutron calorimeter , Symmetry energy , Equation of state , Heavy-ion collision , Korea rare-isotope accelerator
- 발행기관 한국물리학회
- 발행년도 2011
- 총서유형 Journal
- UCI G704-000411.2011.58.2.032
- KCI ID ART001525936
- 본문언어 영어
초록/요약
We have designed a neutron calorimeter dedicated to the measurement of the nuclear symmetry energy in the planned Korea rare-isotope accelerator. The design was optimized to precisely measure the neutron energy with high efficiency in a wide energy range from about 30 to 300 MeV. The final configuration of the detector is a hybrid of the homogeneous and the sampling calorimeters with a veto counter in the front. The homogeneous part is ideal for measuring low-energy neutrons below ∼50 MeV whereas the sampling part is efficient for measuring high-energy neutrons. The detection efficiency is estimated to be about 88% for neutron energies larger than 50 MeV and decreases to ∼78% at 30 MeV.We have estimated the energy resolution as a function of the incident energy based on the time-of-flight method. Assuming an ideal detector performance with null time resolution, the relative energy resolution decreases as the incident neutron energy increases. However, under a more realistic situation with a finite time resolution for the detector, the energy resolution monotonically increases with increasing the neutron energy, following a logarithmic function. Imposing an energy resolution of better than 3% at the highest neutron energy, we find the nominal position of the hybrid calorimeter to be 15 m from the target for a time resolution of 1.0 ns, but the detector needs to be free to move closer to or farther from the target, depending on the physics goal.
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