大型强子对撞机(LHC)上的大型离子对撞机实验(ALICE)将致力于TeV能区重离子碰撞,探测夸克退禁闭的新物质形态——夸克-胶子等离子体(QGP),探索宇宙诞生之初的物态性质。本文介绍其上的新一代电磁谱仪ALICE光子探测器(PHOS),它将用于铅-铅碰撞实验中测量直接光子和衰变光子产物,诊断夸克物质的电磁信号。束流测试结果显示,ALICE光子谱仪——PHOS将能够高效探测0.5~100GeV/c的光子。
A large ion collider experiment (ALICE) at the large hadron collider (LHC) will be indicated to the detection of quark-gluon plasma (QGP) formed in heavy-ion collisions at TeV, and the exploration of the early universe as it was in the first few microseconds after its birth. A high precision electromagnetic calorimeter--ALICE photon spectrometer (PHOS), designed and produced by ALICE collaboration was described in the paper. It was used to detect the prompt- and decay-photons and diagnose the electromagnetic signal of quark-gluon plasma in lead-lead collisions at √SNN= 5. 5 TeV. The beam test results show that PHOS is capable to detect photons efficiently up to 0. 5- 100 GeV/c in ALICE.