SiPM dynamic range for CEPC scintillator-based electromagnetic calorimeter

Abstract A high-granularity scintillator calorimeter readout with silicon photomultipliers (SiPMs) is an electromagnetic calorimeter (ECAL) candidate for experiments at the Circular Electron Positron Collider (CEPC). A critical design parameter of this ECAL candidate is the dynamic range of the SiPMs. This study investigates the SiPM dynamic range required for the CEPC scintillator ECAL. A model is developed on the basis of the operation principles of SiPMs to describe the response of an SiPM to light pulses within one recovery period by considering the cross-talk effect, photon detection efficiency, and number of pixels. The response curve of a 10000-pixel SiPM predicted by the model is consistent with the measured curve within 2% for an incident light pulse of up to 12000 photons. The intrinsic fluctuations of the SiPM response naturally exist in this model, and the correction of the saturation effect in the SiPM response is investigated. Monte Carlo (MC) simulation shows that the algorithm can restore the response linearity of an SiPM for an incident light pulse in which the number of photons is up to around six times the number of SiPM pixels. The model and correction program are implemented for full simulation of the ZH production Z → νν, H → γγ channel to evaluate the impact of the SiPM dynamic range of the CEPC scintillator ECAL on the reconstructed Higgs boson mass and the sensitivity to the Higgs signal in this channel. The results show that the CEPC scintillator ECAL equipped with no less than 4000 SiPM pixels and operated with a light yield of 20 photon-electrons per channel for a single minimum ionizing particle can meet the requirements for Higgs boson precision measurement in the di-photon channel at the CEPC.

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Calibration and Performance of the CMS Electromagnetic Calorimeter in LHC Run2

EPJ Web of Conferences ◽

10.1051/epjconf/202024502027 ◽

2020 ◽

Vol 245 ◽

pp. 02027

Author(s):

Francesca Cavallari ◽

Chiara Rovelli

Keyword(s):

Higgs Boson ◽

Energy Resolution ◽

Mass Measurement ◽

Energy Scale ◽

Boson Mass ◽

Electromagnetic Calorimeter ◽

High Mass ◽

Final State ◽

Z Boson Decays ◽

And Performance

Many physics analyses using the Compact Muon Solenoid (CMS) detector at the LHC require accurate, high resolution electron and photon energy measurements. Excellent energy resolution is crucial for studies of Higgs boson decays with electromagnetic particles in the final state, as well as searches for very high mass resonances decaying to energetic photons or electrons. The CMS electromagnetic calorimeter (ECAL) is a fundamental instrument for these analyses and its energy resolution is crucial for the Higgs boson mass measurement. Recently the energy response of the calorimeter has been precisely calibrated exploiting the full Run2 data, aiming at a legacy reprocessing of the data. A dedicated calibration of each detector channel has been performed with physics events exploiting electrons from W and Z boson decays, photons from π0 and η decays, and from the azimuthally symmetric energy distribution of minimum bias events. This talk presents the calibration strategies that have been implemented and the excellent performance achieved by the CMS ECAL with the ultimate calibration of Run2 data, in terms of energy scale stability and energy resolution.

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Determination of Position Resolution for LYSO Scintillation Crystals Using Geant4 Monte Carlo Code

Advances in High Energy Physics ◽

10.1155/2021/9931708 ◽

2021 ◽

Vol 2021 ◽

pp. 1-5

Author(s):

M. F. O. Yahya ◽

F. Kocak

Keyword(s):

Monte Carlo ◽

Light Yield ◽

Electromagnetic Calorimeter ◽

Monte Carlo Code ◽

Position Resolution ◽

Scintillation Crystals ◽

Simulation Based ◽

High Light Yield ◽

Center Particle ◽

The Impact

LYSO scintillation crystals, due to their significant characteristics such as high light yield, fast decay time, small Moliére radius, and good radiation hardness, are proposed to be used for the electromagnetic calorimeter section of the Turkish Accelerator Center Particle Factory (TAC-PF) detector. In this work, the center of gravity technique was used to determine the impact coordinates of an electron initiating an electromagnetic shower in a LYSO array, in a calorimeter module containing nine crystals, each 25 mm × 25 mm in cross-section and 200 mm in length. The response of the calorimeter module has been studied with electrons having energies in the range 0.1 GeV-2 GeV. By using the Monte Carlo simulation based on Geant4, the two-dimensional position resolution of the module is obtained as σ R mm = 3.95 ± 0.08 / E ⊕ 1.91 ± 0.11 at the center of the crystal.

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Two-Loop Correction to the Higgs Boson Mass in the MRSSM

Advances in High Energy Physics ◽

10.1155/2015/760729 ◽

2015 ◽

Vol 2015 ◽

pp. 1-12 ◽

Cited By ~ 21

Author(s):

Philip Diessner ◽

Jan Kalinowski ◽

Wojciech Kotlarski ◽

Dominik Stöckinger

Keyword(s):

Higgs Boson ◽

Standard Model ◽

Supersymmetric Standard Model ◽

Boson Mass ◽

Strong Interactions ◽

Higgs Boson Mass ◽

Gluino Mass ◽

Loop Correction ◽

Yukawa Couplings ◽

The Impact

We present the impact of two-loop corrections on the mass of the lightest Higgs boson in the minimalR-symmetric supersymmetric standard model (MRSSM). These shift the Higgs boson mass up by typically 5 GeV or more. The dominant corrections arise from strong interactions, and from the gluon and itsN=2superpartners, the sgluon and Dirac gluino, and these corrections further increase with large Dirac gluino mass. The two-loop contributions governed purely by Yukawa couplings and the MRSSMλ,Λparameters are smaller. We also update our earlier analysis which showed that the MRSSM can accommodate the measured Higgs andWboson masses. Including the two-loop corrections increases the parameter space where the theory prediction agrees with the measurement.

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CMS Discovery Potential for the Higgs Boson in the $H \to ZZ^* \to 4e^{\pm}$ Decay Channel. Contribution to the Construction of the CMS Electromagnetic Calorimeter

10.2172/1421450 ◽

2000 ◽

Author(s):

I. Puljak

Keyword(s):

Higgs Boson ◽

Decay Channel ◽

Electromagnetic Calorimeter ◽

Discovery Potential

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Search for dark photons in Higgs boson production via vector boson fusion in proton-proton collisions at $$ \sqrt{s} $$ = 13 TeV

Journal of High Energy Physics ◽

10.1007/jhep03(2021)011 ◽

2021 ◽

Vol 2021 (3) ◽

Author(s):

A. M. Sirunyan ◽

◽

A. Tumasyan ◽

W. Adam ◽

T. Bergauer ◽

...

Keyword(s):

Higgs Boson ◽

Standard Model ◽

Confidence Level ◽

Branching Fraction ◽

Vector Boson ◽

Boson Mass ◽

Higgs Boson Mass ◽

Vector Boson Fusion ◽

Upper Limit ◽

The Standard Model

Abstract A search is presented for a Higgs boson that is produced via vector boson fusion and that decays to an undetected particle and an isolated photon. The search is performed by the CMS collaboration at the LHC, using a data set corresponding to an integrated luminosity of 130 fb−1, recorded at a center-of-mass energy of 13 TeV in 2016–2018. No significant excess of events above the expectation from the standard model background is found. The results are interpreted in the context of a theoretical model in which the undetected particle is a massless dark photon. An upper limit is set on the product of the cross section for production via vector boson fusion and the branching fraction for such a Higgs boson decay, as a function of the Higgs boson mass. For a Higgs boson mass of 125 GeV, assuming the standard model production rates, the observed (expected) 95% confidence level upper limit on the branching fraction is 3.5 (2.8)%. This is the first search for such decays in the vector boson fusion channel. Combination with a previous search for Higgs bosons produced in association with a Z boson results in an observed (expected) upper limit on the branching fraction of 2.9 (2.1)% at 95% confidence level.

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Precision inclusive Higgs physics at e+e− colliders with tracking detectors and without calorimetry

Journal of High Energy Physics ◽

10.1007/jhep09(2020)174 ◽

2020 ◽

Vol 2020 (9) ◽

Author(s):

Patrick Draper ◽

Jonathan Kozaczuk ◽

Scott Thomas

Keyword(s):

Higgs Boson ◽

Cross Section ◽

Tracking System ◽

Inclusive Cross Section ◽

Nuclear Interaction ◽

General Purpose ◽

Boson Mass ◽

Practical Reasons ◽

Identification System ◽

Tracking Detector

Abstract A primary goal of a future e+e− collider program will be the precision measurement of Higgs boson properties. For practical reasons it is of interest to determine the minimal set of detector specifications required to reach this and other scientific goals. Here we investigate the precision obtainable for the e+e−Zhμ+μ−X inclusive cross section and the Higgs boson mass using the di-muon recoil method, considering a detector that has only an inner tracking system within a solenoidal magnetic field, surrounded by many nuclear interaction lengths of absorbing material, and an outer muon identification system. We find that the sensitivity achievable in these measurements with such a tracking detector is only marginally reduced compared to that expected for a general purpose detector with additional electromagnetic and hadronic calorimeter systems. The difference results mainly from multi-photon backgrounds that are not as easily rejected with tracking detectors. We also comment on the prospects for an analogous measurement of the e+e−→Zh→e+e−X inclusive cross section. Finally, we study searches for light scalars utilizing the di-muon recoil method, estimating the projected reach with a tracking or general purpose detector.

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The impact of topical lidocaine and timing of LMA removal on the incidence of airway events during the recovery period in children: a randomized controlled trial

BMC Anesthesiology ◽

10.1186/s12871-021-01235-7 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Ruiqiang Sun ◽

Xiaoyun Bao ◽

Xuesong Gao ◽

Tong Li ◽

Quan Wang ◽

...

Keyword(s):

Randomized Controlled Trial ◽

Controlled Trial ◽

Recovery Period ◽

Awake State ◽

Randomized Controlled ◽

Laryngeal Spasm ◽

Topical Lidocaine ◽

Lubricant Application ◽

Pacu Stay ◽

The Impact

Abstract Background The timing of laryngeal mask airway (LMA) removal remains undefined. This study aimed to assess the optimal timing for LMA removal and whether topical anesthesia with lidocaine could reduce airway adverse events. Methods This randomized controlled trial assessed one-to-six-year-old children with ASA I-II scheduled for squint correction surgery under general anesthesia. The children were randomized into the LA (lidocaine cream smeared to the cuff of the LMA before insertion, with mask removal in the awake state), LD (lidocaine application and LMA removal under deep anesthesia), NLA (hydrosoluble lubricant application and LMA removal in the awake state) and NLD (hydrosoluble lubricant application and LMA removal in deep anesthesia) groups. The primary endpoint was a composite of irritating cough, laryngeal spasm, SpO2 < 96%, and glossocoma in the recovery period in the PACU. The secondary endpoints included the incidence of pharyngalgia and hoarseness within 24 h after the operation, duration of PACU stay, and incidence of agitation in the recovery period. The assessor was unblinded. Results Each group included 98 children. The overall incidence of adverse airway events was significantly lower in the LA group (9.4%) compared with the LD (23.7%), NLA (32.6%), and NLD (28.7%) groups (P=0.001). Cough and laryngeal spasm rates were significantly higher in the NLA group (20.0 and 9.5%, respectively) than the LA (5.2 and 0%, respectively), LD (4.1 and 1.0%, respectively), and NLD (9.6 and 2.1%, respectively) groups (P=0.001). Glossocoma incidence was significantly lower in the LA and NLA groups (0%) than in the LD (19.6%) and NLD (20.2%) groups (P< 0.001). At 24 h post-operation, pharyngalgia incidence was significantly higher in the NLA group (15.8%) than the LA (3.1%), LD (1.0%), and NLD (3.2%) groups (P< 0.001). Conclusions LMA removal in the awake state after topical lidocaine anesthesia reduces the incidence of postoperative airway events. Trial registration ChiCTR, ChiCTR-IPR-17012347. Registered August 12, 2017.

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