SiPM-on-Tile Modules for the CMS High Granularity Calorimeter

For the HL-LHC phase, the calorimeter end-cap of the CMS detector will be upgraded with a High Granularity Calorimeter (HGCAL) with increased transverse and longitudinal granularity to cope with the expected pileup and radiation. In regions where radiation levels allow, the hadronic calorimeter will use scintillator tiles coupled to silicon photomultipliers (SiPM-on-tiles) as active materials. The HGCAL Tilemodule is the basic detector module of this region and can hold up to 144 SiPM-on-tile channels and two readout electronic chips (HGCROCs). Performances of various SiPM-on-tiles, including different SiPM sizes, tile sizes, scintillator materials, production technologies and irradiated SiPMs, were quantified at beam tests using \SI{3}{GeV} electron beams at DESY-II. Further tests were conducted in temperature-controlled chambers to quantify the relationship between noise and leakage current passing through irradiated SiPMs on Tilemodules. The results from these tests were used in a model to obtain estimates of the signal-to-noise ratio (SNR) at the detector's end-of-life. Based on the estimates, changes to the final scintillator layout are proposed to obtain SNR>3 throughout the detector, including using smaller scintillator tiles in the frontmost layers and increasing the use of SiPMs with 3 \times \SI{3}{mm²} active area in the detector

Latest Tests of the CMS HGCAL Tileboard Prototypes

For the HL-LHC phase, the calorimeter endcap of the CMS detector will be upgraded with a High Granularity Calorimeter (HGCAL), a sampling calorimeter that will use silicon sensors as well as scintillator tiles read out by silicon photomultipliers (SiPMs) as active material (SiPM-on-tile). The complete HGCAL will be operated at −30∘C. The SiPMs will be used in areas where the expected radiation dose during the lifetime of the detector is up to 5×1013 neq/cm2. The basic detector unit in the SiPM-on-tile part is the tile module, consisting of a PCB with one or two HGCROC ASICs, reading out up to 96 tiles with SiPMs. The design of the SiPM-on-tile part is inspired by the CALICE AHCAL.In the calorimeter, the response of each SiPM-on-tile on the energy scale will be calibrated using the MIP signal. This is compromised by radiation damage decreasing the scintillator light output and increasing the SiPM dark current-induced noise. SiPM irradiation tests provide data on the current increase as a function of accumulated neutron fluence. From this increase in current, the increase in noise for a fixed SiPM bias voltage can be predicted. Tests were conducted on SiPMs irradiated to 2×1012 neq/cm2 mounted on a tileboard, at temperatures ranging between −30∘C and +30∘C using a climate chamber. Results from these tests will be reported

Beam Tests of the First CMS HGCAL Tileboard Prototypes

For the HL-LHC phase, the calorimeter endcap of the CMS detector will be upgraded with a High Granularity Calorimeter (HGCAL), a sampling calorimeter which will use silicon sensors as well as scintillator tiles read out by silicon photomultipliers (SiPMs) as active material (SiPM-on-tile). The complete HGCAL will be operated at -30 degC. The SiPMs will be used in areas where the expected radiation dose during the lifetime of the detector is up to 5*10^13 neq/cm^2. The design of the SiPM-on-tile part is inspired by the CALICE AHCAL.The basic detector unit in the SiPM-on-tile part is the tilemodule, consisting of a PCB with one or two HGCROC ASICs, reading out up to 96 tiles with SiPMs. The first functional tilemodule prototypes have been constructed with HGCROC2 ASICs and SiPMs which are candidates for the HGCAL production. They have undergone beam tests at DESY and Fermilab, investigating the interplay of the components and evaluating the performance with several scintillator tile types. First test were also performed with irradiated SiPMs. We will report on these tests, which were all performed in 2020, and the work still to come using beams

Evaluation of the Performance ofSiPM-on-Tiles at the End of Lifeof the CMS HGCAL Upgrade

For the HL-LHC phase, the calorimeter endcap of the CMS detector will be upgraded with a High Granularity Calorimeter (HGCAL), a sampling calorimeter that will use silicon sensors as well as scintillator tiles read out by silicon photomultipliers (SiPMs) as active material (SiPM-on-tile). The design of the SiPM-on-tile section was inspired by the CALICE AHCAL. The complete HGCAL will be operated at −30∘C.The basic detector unit in the SiPM-on-tile section is the tile module, consisting of a PCB with one or two HGCROC ASICs, reading out up to 96 SiPM-on-tiles. Signals from MIPs passing through the SiPM-on-tiles are used to quantify the performance of SiPM-on-tiles. With irradiation, their performance degrades while increasing the noise. The ratio between the MIP signal and noise is known as the signal-to-noise ratio (SNR). In order to maintain an SNR>3 at end of the detector lifetime, SiPMs will be used in areas where the expected radiation dose during the lifetime of the detector is less than 5× 1013 neq/cm2.A series of tests were conducted to quantify the performance of SiPM-on-tiles mounted on tile modules including beam tests and cold tests at −30∘C. These tests were also repeated using irradiated SiPMs mounted on the tile modules. These tests were then used to extrapolate the performance expectations at the detector’s end of life

Latest Beam Tests of CMS HGCAL Tilemodule Prototypes

For the HL-LHC phase, the calorimeter endcap of the CMS detector will be upgraded with a High Granularity Calorimeter (HGCAL), a sampling calorimeter which will use silicon sensors as well as scintillator tiles read out by silicon photomultipliers (SiPMs) as active material (SiPM-on-tile). The complete HGCAL will be operated at -30 degC. The SiPMs will be used in areas where the expected radiation dose during the lifetime of the detector is up to 5*10$^{13}$ neq/cm$^2$. The design of the SiPM-on-tile part is inspired by the CALICE AHCAL.The basic detector unit in the SiPM-on-tile part is the tilemodule, consisting of a PCB with one or two HGCROC ASICs, reading out up to 96 tiles with SiPMs. To acquire the data as well as to send the fast and slow control commands, monitor temperature and voltages from the tilemodules a dedicated DAQ system has been designed and implemented. This DAQ system was tested alongside the latest generation of tilemodules at the October 2021 testbeam at DESY as well as tests at -30 degrees Celsius were conducted using a climate chamber. Results from these tests will be reported

Scintillator Section of the CMS High Granularity Calorimeter Upgrade (HGCAL)

For the HL-LHC phase, the calorimeter endcap of the CMS detector will be upgraded with a High Granularity Calorimeter (HGCAL), a sampling calorimeter that will use silicon sensors as well as scintillator tiles read out by silicon photomultipliers (SiPMs) as active material (SiPM-on-tile). The design of the SiPM-on-tile section was inspired by the CALICE AHCAL. The complete HGCAL will be operated at -30°C.The basic detector unit in the SiPM-on-tile section is the tile module, consisting of a PCB with one or two HGCROC ASICs, reading out up to 96 SiPM-on-tiles. For geometric reasons, the tile modules and the tiles on the tile modules will increase in size with increasing radial distance from the beam pipe. Eight variations of tile modules have been designed to cover the full area of 340 m². This includes the use of two different SiPM sizes and 21 different tile sizes manufactured using two different materials.Tests on tile modules have been conducted at beam tests at DESY-II and CERN SPS and in lab experiments including using climate chambers operating at -30°C. Production of tile modules for the upgrade is foreseen to start next year. An overview of the current status and production plans of the SiPM-on-tile section will be presented in this poster

SiPM-on-Tile Technology for the Phase II upgrade of the CMS High Granularity Endcap Calorimeter (HGCAL)

The CMS Collaboration is preparing to replace its endcap calorimeters for the HL-LHC era with a high-granularity calorimeter (HGCAL). The HGCAL will have fine segmentation in both the transverse and longitudinal directions, and will be the first such imaging calorimeter specifically optimized for particle-flow reconstruction to operate at a colliding-beam experiment. It is a sampling calorimeter that will use silicon sensors as well as scintillator tiles read out by silicon photomultipliers (SiPMs) as the active material. The HGCAL will be operated at -30° C. The SiPMs will be used in areas where the expected radiation dose during the lifetime of the detector is up to 5x10¹³ n/cm².The technology consisting of scintillator tiles of a few centimetre lengths read out individually by SiPMs, is known as the SiPM-on-tile technology. The basic detector unit in the SiPM-on-tile part is the tileboard consisting of a PCB with one or two HGCROC ASICs, SiPMs, scintillators and other onboard electronic systems. These modules have undergone beam tests at DESY II, investigating the interplay of the components and evaluating the performance with several types of the scintillator tiles and SiPM sizes. This poster will give an overview on of the SiPM-on-tile technology and report on these beam tests

Beam Tests of the first CMS HGCAL Tilemodule prototypes

For the HL-LHC phase, the calorimeter endcap of the CMS detector will be upgraded with a High Granularity Calorimeter (HGCAL), a sampling calorimeter which will use silicon sensors as well as scintillator tiles read out by silicon photomultiplier (SiPMs) as active material (SiPM-on-tile). The complete HGCAL will be operated at -30 °C. The SiPMs will be used in areas where the expected radiation dose during the lifetime of the detector is up to 5x10^13 neq/cm^2. The design of the SiPM-on-tile part is inspired by the CALICE AHCAL.The basic detector unit in the SiPM-on-tile part is the tile module, consisting of a PCB with one or two HGCROC ASICs, reading out up to 96 tiles with SiPMs. The first functional tile module prototypes have been constructed with HGCROC2 ASICs and SiPMs which are candidates for the HGCAL production. They have undergone beam tests at DESY and Fermilab, investigating the interplay of the components and evaluating the performance with several scintillator tile types. The first test with irradiated SiPMs was also performed. We will report on these tests, which were all performed in 2020, and the work still to come using beams