The Upgrade of the CMS RPC System during the First LHC Long Shutdown
M. Tytgat, A. Marinov, P. Verwilligen, N. Zaganidis, A. Aleksandrov, V. Genchev, P. Iaydjiev, M. Rodozov, M. Shopova, G. Sultanov, Y. Assran, M. Abbrescia, C. C… 展开作者
M. Tytgat, A. Marinov, P. Verwilligen, N. Zaganidis, A. Aleksandrov, V. Genchev, P. Iaydjiev, M. Rodozov, M. Shopova, G. Sultanov, Y. Assran, M. Abbrescia, C. Calabria, A. Colaleo, G. Iaselli, F. Loddo, M. Maggi, G. Pugliese, L. Benussi, S. Bianco, M. Caponero, S. Colafranceschi, F. Felli, D. Piccolo, G. Saviano, C. Carrillo, U. Berzano, M. Gabusi, P. Vitulo, M. Kang, K. S. Lee, S. K. Park, S. Shin, A. Sharma
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9 pages, 6 figures, presented by M.Tytgat at the XI workshop on Resistive Plate Chambers and Related Detectors (RPC2012), INFN - Laboratori Nazionali di Frascati, February 5-10, 2012
The CMS muon system includes in both the barrel and endcap region Resistive Plate Chambers (RPC). They mainly serve as trigger detectors and also improve the reconstruction of muon parameters. Over the years, the instantaneous luminosity of the Large Hadron Collider gradually increases. During the LHC Phase 1 (~first 10 years of operation) an ultimate luminosity is expected above its design value of 10^34/cm^2/s at 14 TeV. To prepare the machine and also the experiments for this, two long shutdown periods are scheduled for 2013-2014 and 2018-2019. The CMS Collaboration is planning several detector upgrades during these long shutdowns. In particular, the muon detection system should be able to maintain a low-pT threshold for an efficient Level-1 Muon Trigger at high particle rates. One of the measures to ensure this, is to extend the present RPC system with the addition of a 4th layer in both endcap regions. During the first long shutdown, these two new stations will be equipped in the region |eta|<1.6 with 144 High Pressure Laminate (HPL) double-gap RPCs operating in avalanche mode, with a similar design as the existing CMS endcap chambers. Here, we present the upgrade plans for the CMS RPC system for the fist long shutdown, including trigger simulation studies for the extended system, and details on the new HPL production, the chamber assembly and the quality control procedures.
The CMS experiment collected around 150 fb$^{-1}$ of proton-proton collision data at $\sqrt{s}$ = 13 TeV during the Run-2 data taking period of LHC. The CMS RPC system provided redundant information for robust muon triggering, reconstruction and identification. To ensure stable data taking, the CMS RPC collaboration has performed detector operation, calibration and performance studies. After the end of Run-2, it was started the second LHC long shutdown period (LS2), an important opportunity for maintenance and preparation for the next data taking period (Run-3) and the installation of services…
ALICE μ子触发器目前由一个探测器产生，该探测器目前由72个以最大雪崩模式运行的胶木单间隙电阻板室组成，排列在四个5.5x6.5平方米的探测平面上。为了满足即将从2021年开始的LHC高亮度运行的要求，其中ALICE将以连续模式读出，μ子触发器将成为μ子标识符，并将进行重大升级。在当前设置中，来自约21k条的信号由2400个非放大前端（FEE）卡区分，其阈值由外部模拟电压提供（每个腔室侧一个）。所有这些卡将被配备有前置放大级的鉴别器所取代，这将允许降低探测器的操作高压，从而延长其寿命。此外，它们的参考阈值将通过无线（和每个腔室侧链接的I2C）传递，允许在单个卡级别调整值。此外，24个暴露最多的室将被更换为新的，配备高质量（即更光滑的表面）电木层压板。报告了在测试台和探测器上使用的新FEE卡以及在新RPC室（带有宇宙射线）上进行的测试。
Resistive Plate Chambers are used in the ATLAS experiment for the muon trigger and two coordinate measurements in the central region. In preparation for the coming years of LHC running at higher luminosity, besides the New Small Wheel project which is expected to complement the ATLAS muon spectrometer in the endcap regions, a smaller size project, known as BIS78, is being developed with a foreseen installation during the LHC Long Shutdown 2. The BIS78 project will reinforce the fake muon rejection and the selectivity of the muon trigger in the transition region between the ATLAS barrel and end…
During Phase-2 of the LHC, known as the High Luminosity LHC (HL-LHC), the accelerator will increase its instantaneous luminosity to 5 $\times$ 10$^{34}$ cm$^{-2}$ s$^{-1}$, delivering an integrated luminosity of 3000 fb$^{-1}$ over 10 years of operation starting from 2027. In view of the HL-LHC, the CMS muon system will be upgraded to sustain efficient muon triggering and reconstruction performance. Resistive Plate Chambers (RPCs) serve as dedicated detectors for muon triggering due to their excellent timing resolution, and will extend $|η|$ (pseudorapidity) up to a region of 2.4. Before Long …
Performance of Resistive Plate Chambers installed during the first long shutdown of the CMS experiment
CMS实验位于欧洲核子研究中心大型强子对撞机，有一个由三种不同的探测器技术组成的冗余μ子系统：阴极条室（在前部区域），漂移管（在中部区域）和电阻板室（其中部和前部区域）。所有这三个都用于μ子重建和触发。在LHC（2013-2014）的第一次长停堆（LS 1）期间，CMS μ子系统已经升级，在第四个前站上新安装了144个RPC。新的腔室确保并提高了LHC Run 2在高亮度条件下的μ子触发效率。这些室已成功安装并投入使用。该系统已成功运行，并对实验数据进行了采集和分析。将介绍新安装的RPC的性能结果。
The reduction of the average charge per count in the gas along with the capability to discriminate very small signals from noise can allow an efficient and long-term Resistive Plate Chamber detector operation in high radiation background environment. This goal has been reached during the R&D program of the BIS78 upgrade project of the ATLAS detector at LHC through the deep integration of a fast (100 ps peaking time) and sensitive (as small as 100 `V threshold) Front- End electronics (FE) with a very large size detector structure. This innovative RPC integration concept pivots on a newly concei…
The CMS detector at the CERN LHC features a silicon pixel detector as its innermost subdetector. The original CMS pixel detector has been replaced with an upgraded pixel system (CMS Phase-1 pixel detector) in the extended year-end technical stop of the LHC in 2016/2017. The upgraded CMS pixel detector is designed to cope with the higher instantaneous luminosities that have been achieved by the LHC after the upgrades to the accelerator during the first long shutdown in 2013-2014. Compared to the original pixel detector, the upgraded detector has a better tracking performance and lower mass with…
During the upcoming High Luminosity phase of the Large Hadron Collider (HL-LHC), the integrated luminosity of the accelerator will increase to 3000 fb$^{-1}$. The expected experimental conditions in that period in terms of background rates, event pileup, and the probable aging of the current detectors present a challenge for all the existing experiments at the LHC, including the Compact Muon Solenoid (CMS) experiment. To ensure a highly performing muon system for this period, several upgrades of the Resistive Plate Chamber (RPC) system of the CMS are currently being implemented. These include …
The ALICE experiment at CERN has undergone a major upgrade during the Long Shutdown 2 of the LHC during 2019-2021. A key element is the installation of the new Inner Tracking System 2 (ITS2). The new ITS2 based on CMOS Monolithic Active Pixel Sensors will significantly improve the impact parameter resolution and the tracking efficiency, especially for particles with low transverse momenta, as well as the readout-rate capability. In the following, the upgrade and its commissioning status as well installation status will be outlined.
Characterization of tetrafluoropropene-based gas mixtures for the Resistive Plate Chambers of the ALICE muon spectrometer
欧洲核子研究中心大型强子对撞机ALICE实验的μ子识别系统是基于电阻板室（RPC）探测器。这些RPC在所谓的最大雪崩模式下使用由正乙烷（C $_{2}$ H $_{2}$ F $_{4}$）、六氟化硫（SF $_{6}$）和异丁烷（i-C $_{4}$ H $_{10}$）制成的气体混合物操作。所有这些成分都是温室气体：特别是前两种气体，由于欧洲联盟最近的条例，已经逐步停止生产，其成本正在逐步增加。因此，为了减少RPC操作对环境的影响，并且出于经济原因，寻找新的生态友好的气体混合物变得极其重要。由于类似的化学结构，氢氟烯烃似乎是替代C $_{2}$ H $_{2}$ F $_{4}$的合适的候选物，这是由于它们非常低的GWP，尤其是具有商品名HFO 1234 ze的正丙烯（C $_{3}$ H $_{2}$ F $_{4}$）。为了确定符合未来几年ALICE环境运行要求的环保气体混合物，已经建立了一个专门的实验装置，对有前途的气体混合物进行研发研究。测量已经进行了一个小尺寸的RPC配备了前端的电子设备，提供信号放大，开发ALICE操作在高亮度后，LHC长2002。本文讨论了添加CO $_{2}$的HFO 1234 ze基混合物，以及i-C $_{4}$ H $_{10}$和SF $_{6}$在这种混合物中作为猝灭剂的作用。
ALICE Inner Tracking System Upgrade: construction and commissioning
ALICE（A Large Ion Collider Experiment）是欧洲核子研究中心的大型强子对撞机实验，主要用于研究重离子碰撞中产生的强相互作用物质，并致力于表征夸克-胶子等离子体。为了实现LHC运行3和4的物理计划，ALICE正在进行第二次长时间LHC关闭期间对实验设备进行重大升级。ALICE升级的一个关键要素是用一个全新的硅基探测器取代内部跟踪系统（ITS），其功能将允许重建罕见的物理通道，这些通道在LHC运行1和2期间使用的ITS布局之前无法访问。实现这种性能提升的技术是采用定制设计的MAPS（单片有源像素传感器）作为检测元件。在本程序中，将详细介绍ITS升级的建设和调试状况。模块的建设将很快完成，与此同时，实验室的调试正在使用已经集成在探测器中的组件进行。
The LHC is expected to increase its center-of-mass energy from 13 TeV to 14 TeV for Run 3 scheduled from 2022 to 2024. After Run 3, upgrades for the High-Luminosity-LHC (HL-LHC) programme are planned and the operation will start in 2027, increasing the instantaneous luminosity to 5.0 -- 7.5 times its nominal luminosity. Continuous upgrades of the ATLAS trigger system are planned to cope with the high event rate and to keep the physics acceptance. During the long shutdown period before Run 3, new detectors will be installed to improve the trigger performance. New trigger logic, combining inform…
The high-luminosity phase of the Large Hadron Collider (HL-LHC) will result in ten times higher particle background than measured during the first phase of LHC operation. In order to fully exploit the highly-demanding operating conditions during HL-LHC, the Compact Muon Solenoid (CMS) Collaboration will use Gas Electron Multiplier (GEM) detector technology. The technology will be integrated into the innermost region of the forward muon spectrometer of CMS as an additional muon station called GE11. The primary purpose of this auxiliary station is to help in muon reconstruction and to control le…
Fast Beam Condition Monitor for CMS: performance and upgrade
CMS束流和辐射监测子系统BCM1F（快速束流状态监测器）由8个独立的金刚石传感器组成，位于像素探测器体积内的束管周围，用于快速逐束流监测束流背景和碰撞产物。此外，正在努力将BCM1F用作在线光度监测器。BCM1F将在LHC中有束流时运行，其数据采集独立于CMS探测器的数据采集，因此即使CMS没有采集数据，它也会提供亮度。报告给出了在LHC运行I期间BCM1F的性能，包括2012年完成的van der Meer扫描和在线光度监测的结果。为了满足更高亮度和25 ns聚束间距的要求，在即将到来的关机期间必须对系统进行几项更改，包括升级电子设备和精确的增益监控。显示了运行II制备的第一批结果。
The expected radiation background in the CMS RPC system has been studied using the MC prediction with the CMS FLUKA simulation of the detector and the cavern. The MC geometry used in the analysis describes very accurately the present RPC system but still does not include the complete description of the RPC upgrade region with pseudorapidity $1.9 < \lvert η\rvert < 2.4$. Present results will be updated with the final geometry description, once it is available. The radiation background has been studied in terms of expected particle rates, absorbed dose and fluence. Two High Luminosity LHC (HL-LH…
Resistive Plate Chamber Detector Construction and Certification: State-of-the-Art Facilities at the Max Planck Institute for Physics, in Partnership with Industrial Partners
As part of the Compact Muon Solenoid experiment Phase-II upgrade program, new Resistive Plate Chambers will be installed in the forward region. High background conditions are expected in this region during the high-luminosity phase of the Large Hadron Collider, therefore an improved RPC design has been proposed with a new front-end electronics to sustain a higher rate capability and better time resolution. A new technology is used in the front-end electronics resulting in very low achievable thresholds of the order of several fC. Crucial in the design of the improved RPC is the capability of a…
The ALICE Collaboration completed the upgrade of the detector and is now commissioning for the beginning of the data taking during LHC Run 3. In parallel, R&D activities and simulation studies are being performed to define the future of the experiment beyond LHC Run 3. Two detector upgrades are foreseen for the next long shutdown (LS3). The first is the replacement of the three layers of the inner tracking system closest to the beam with a novel vertex detector consisting of curved wafer-scale ultra-thin silicon sensors arranged in perfectly cylindrical layers to improve impact parameter resol…
The ALICE experiment profited of the Long Shutdown during 2019-2021 in order to expand its physics capabilities and fully profit from the increased LHC luminosity in Run 3. The Inner Tracking System has been replaced with a new silicon tracker based on MAPS technology, and a new tracking device has been added in front of the Muon Spectrometer to improve its vertexing capabilities. The wire chambers for TPC readout have been replaced with new GEM detectors which will minimize ion backflow and allow for continuous data taking: moreover, a new detector array dedicated to fast triggering has been …
