Reconstruction methods for the bar PANDA Time of Propagation Disc DIRC
Reconstruction methods for the bar PANDA Time of Propagation Disc DIRC
复制标题
PANDA 传播时间盘 DIRC 条的重建方法
DOI：
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发表时间：
2009
期刊：
影响因子：
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通讯作者：
M. Zühlsdorf
中科院分区：
文献类型：
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作者：
O. Merle;I. Brodski;M. Düren;K. Föhl;A. Hayrapetyan;P. Koch;B. Kröck;M Sporleder;M. Zühlsdorf
传播时间圆盘（ToP）探测器是一种新型切伦科夫探测器，是为ANDA粒子识别系统而提出的。内部反射切伦科夫辐射探测（DIRC）探测器是环形成像切伦科夫探测器的一个亚型。因此，工作原理也是基于发射的切伦科夫光子的空间角度测量。ToP Disc DIRC概念涉及两种新颖的方法。首先，将辐射体实现成圆盘状，这是以前从未做过的；其次，切伦科夫角不是通过空间读出测量的，而是通过一个空间坐标和一个快速单光子时间信号（σ < 50 ps）重建的。光子不仅在辐射体内部被全反射，而且部分被圆盘边缘的介电镜反射，导致必须重建的复杂光子轨迹。此外，ANDA无法为给定的入射粒子提供可用的开始时间。因此，测量数据只包括光子的探测时间，而不包括光子的传播时间。由于工作原理不同，以往的DIRC重建方法无法应用。新的专门的重建方法已经开发出来，并将被提出。基于蒙特卡罗数据（Geant4）的初步分辨率研究证明，单线和多线重建都是可行的。
The Time of Propagation (ToP) Disc DIRC is a novel type of Cherenkov detector, proposed for the particle identification system in ANDA. DIRC detectors (detection of internal reflected Cherenkov radiation) are a subtype of ring imaging Cherenkov detectors. Therefore the working principle is also based on spacial angle measurement of emitted Cherenkov photons. The ToP Disc DIRC concept involves two novel approaches. Firstly the radiator is realized in shape of a disc, what has never been done before, and secondly the Cherenkov angle is not measured by a spacial readout but reconstructed from one spacial coordinate and a fast single-photon time signal (σ < 50 ps). Photons are not only total reflected inside the radiator but also partly reflected by dielectric mirrors at the rim of the disc, leading to complicated photon tracks which have to be reconstructed. In addition, ANDA is not able to provide a useable start time for a given incident particle. Therefore measured data includes only the photons time of detection and not time of propagation. Previous approaches to DIRC reconstruction cannot be applied due to the different working principles. New specialized reconstruction methods have been developed and will be presented. Preliminary resolution studies based on Monte Carlo data (Geant4) proof that reconstruction of single tracks as well as multiple tracks is feasible.