今年RHIC 將有二十七週的運轉時間，主要的加速核種為金核與極化質子，PHOBOS 實驗將針對金核的對撞收集物理數據，在本年度的實驗規劃中，金核對撞的質心能量約為40TeV，離子束的平均亮度為3x1026cm2s-4，PHOBOS 偵測器將以500Hz 的觸發率收集事件，以這個速率，兩個月所收集的數據量將是以往一年運轉的數據，也因此讓我們更能準確的檢驗以前的結果。尤其我們計畫藉著PHOBOS 探測器的獨特寬廣粒子接受度特性，涵蓋現今大部份可以量測的相空間，對於金金原子核對撞的帶電粒子子方位角相干性和質心能量、中心度、膺快度和橫向動量的函數關係，進行系統化的研討。相對論重離子對撞中的集體粒子流研究是很重要的，因為它可以提供諸如反應區最初碰撞空間的異向性、在早期碰撞中的情況、以及碰撞進展過程中的熱化程度等相關資訊。此外，此種效應也會影響其他觀測量，如雙粒子相干函數(HBT)、粒子譜和橫向動量分佈斜率。量測帶電粒子方位角相干性一直是RHIC 能量區值得探討的豐富課題之一。這些研究可以提供對於如對撞幾何和合作核子飽和效應的最初碰撞狀態和往後流體動力學的演變過程之瞭解。 RHIC will be operated 27 weeks in this fiscal year. It provides gold-gold head on collisions at 40 TeV of center mass energy with average luminosity around 3x1026cm2s-4. In order to increase the data collection, PHOBOS trigger system has been upgraded to 500 Hz. Under this circumstance, the data accumulation in two months will be equilibrant to last year』s. We will continue the participation of Quark-Gluon Plasma (QGP) search in PHOBOS experiment at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory, USA. In the first two physics runs, the RHIC accelerator has already proven enormous versatility by colliding nuclei at four different energies differing by an order of magnitude. The data provides an important connection of earlier lower energy studies at CERN to the highest energy collisions yet created in the laboratory. The PHOBOS experiment has exploited this unprecedented range in energy with their systematic measurement of particle production under different conditions, which shows the emergence of a surprising scaling behavior in the RHIC energy regime. This result may offer clues to the inner workings of the forces that govern the structure of matter. And we will concentrate on HBT study to measure the size of fireball and its expansion rate. 研究期間：9308 ~ 9407
