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Crystals are used as a homogeneous calorimetric medium in many high-energy physics experiments. For some experiments, performance has to be ensured in very difficult operating conditions, like a high radiation environment, very large particle fluxes, high collision rates, placing constraints on response and readout time. An overview is presented of recent achievements in the field, with particular attention given to the performance of Lead Tungstate (PWO) crystals exposed to high particle fluxes.

We report on the development of a digital hadron calorimeter for the future International Linear Collider. Te calorimeter is of the sandwich type with iron absorber plates and resistive plate chamber as active medium. The readout pads are very finely segmented, with an area of 1 cm², and are being read out digitally. We present the design, construction and testing of various prototype chambers as well as the development of a readout system capable of handling a large number of channels. We plan to construct a 1 m³ prototype section of the calorimeter containing approximately 400,000 channels. The section will undergo testing in various particle beams.

The CMS Electromagnetic Calorimeter (ECAL), is a high granularity lead tungstate (PbWO₄) crystal calorimeter operating at the CERN LHC. The ECAL performance has been crucial in the discovery and subsequent characterization of the Higgs boson. The original ECAL design considerations, and the improvements to the energy reconstruction and energy calibration algorithms to cope with the LHC Run II are described. For the High-Luminosity LHC (HL-LHC) upgrades to ECAL are necessary. The crystals in the barrel region will be retained, defining the HL-LHC CMS barrel electromagnetic calorimeter ECAL. The readout electronics will be upgraded and operating at lower temperatures, to maintain the required performance of ECAL from 2027 onwards. The new readout electronics, the timing resolution and the electron and photon reconstruction efficiencies and energy resolution expected for HL-LHC are presented. The performance relevant to a number of key Higgs decay channels is reported.

The Compact Muon Solenoid (CMS) electromagnetic calorimeter (ECAL) is a high granularity lead tungstate crystal calorimeter operated at the CERN LHC. The future High Luminosity upgrade of the LHC will provide unprecedented instantaneous and integrated luminosity with up to 200 collisions per bunch-crossing [pileup (PU)]. The CMS detector is therefore undergoing an extensive upgrade program to prepare for these demanding conditions. In the ECAL barrel region, the crystals will continue to perform well. The Avalanche Photodiodes (APDs) detecting the scintillation light will also continue to be operational, with some increase in noise that will be mitigated by reducing the operational temperature. Nonetheless, the entire readout and trigger electronics will need to be replaced to cope with the harsh conditions and increased trigger latency requirements. We plan a 25-fold improved readout granularity and a factor 4 sampling rate increase. The timing precision is used in important physics measurements and it is speculated that further improved time information could be exploited for PU mitigation and for the photons assignment to the correct collision vertex. As presented in this paper the endcaps region calorimeter needs to be replaced due to irrecoverable radiation damage of the crystals in the forward region. The upgraded ECAL will preserve the energy resolution, and will improve on time resolution for photons and electrons. In this paper, the ongoing R&D activities for the ECAL barrel readout electronics upgrade are presented.

The CMS Electromagnetic Calorimeter (ECAL) is the largest crystal calorimeter operating in a high energy physics experiment. Since its installation in CMS, it has made fundamental contributions to the CMS physics program by precisely measuring the energy, position and timing of photons, electrons and hadronic jets. The excellent ECAL energy resolution facilitated the observation of the Higgs boson in its two photon decay mode in 2012. These important results have been achieved due to the continuous efforts to improve the detector hardware, firmware and software, as well as the energy and timing reconstruction and calibration methods that have been continuously developed and evolved to exploit the full potential of the calorimeter.

A high-level historical overview of the design, construction and operation of the ECAL over more than 10 years will be presented. The talk will review the initial expectations for detector performance and the plans for operation. These expectations will then be compared to the actual performance achieved during LHC operations. The techniques that have been developed and exploited to maintain the highest operational efficiency and achieve the ultimate energy resolution will also be described. In particular, in-situ crystal and photodetector performance, trigger performance, energy resolution and timing resolution will be addressed. The impacts of ageing on detector performance and the challenges of monitoring and correcting for these effects will also be highlighted. The talk will summarise the lessons learned during the construction and operation phases of the calorimeter, with a prospective look at the CMS calorimeters upgrades for the High Luminosity Collider HL-LHC.

In the present study, the activity of the new water-soluble cationic meso-tetra(4-N-oxyethylpyridyl)porphyrin and its Zn, Ag and Co metal derivatives as anti-tumor agents was explored. The tumor was induced by 7,12-dimethylbenz[a]antracene (DMBA) on rats of Wistar strain. The levels of DNA damage induced by porphyrins T4OEPyP, AgT4OEPyP, ZnT4OEPyP and CoT4OEPyP in tumor tissue were analyzed. Thermodynamic parameters of DNA were investigated by thermal melting method and differential scanning microcalorimetry to understand the differences in DNA structure of three types of rat: normal, dieseased with tumor, and treated by porphyrins. Agarose gel electrophoresis method was used to detect porphyrin-induced apoptosis or necroses. Based on the data obtained, we concluded that the investigated ZnTOEPyP and AgTOEPyP porphyrins have more anti-tumor activity than CoTOEPyP and TOEPyP.

Cellular shape memory alloys (SMAs) are very promising smart materials able to combine functional properties of the material with lightness, stiffness, and damping capacity of the cellular structure. Their processing with low modification of the material properties remains an open question. In this work, the laser weldability of CuZnAl SMA in the form of open cell foams was studied. The cellular structure was proved to be successfully welded in lap joint configuration by using a thin plate of the same alloy. Softening was seen in the welded bead in all the investigated ranges of process speed as well as a double stage heat affected zone was identified due to different microstructures; the martensitic transformation was shifted to higher temperatures and the corresponding peaks were sharper with respect to the base material due to the rapid solidification of the material. Anyways, no compositional variations were detected in the joints.

The electromagnetic calorimeter (ECAL) of the Compact Muon Solenoid Experiment (CMS) is operating at the Large Hadron Collider (LHC) with proton-proton collisions at 13 TeV center-of-mass energy and at a bunch spacing of 25 ns. Upgrades are necessary for the High-Luminosity upgrade of the LHC (HL-LHC). We review the design and R&D studies for the CMS ECAL crystal calorimeter upgrade. We present test beam results of hadron irradiated PbWO₄ crystals up to fluences expected at the HL-LHC. We also report on the R&D for the new readout and trigger electronics, which must be upgraded due to the increased trigger and latency requirements at the HL-LHC.

The High Luminosity LHC (HL-LHC) will integrate 10 times more luminosity than the LHC, posing significant challenges for radiation tolerance and event pileup on detectors, especially for forward calorimetry, and hallmarks the issue for future colliders. As part of its HL-LHC upgrade program, the CMS Collaboration is designing a High Granularity Calorimeter (HGCAL) to replace the existing endcap calorimeters. It features unprecedented transverse and longitudinal segmentation for both electromagnetic (CE-E) and hadronic (CE-H) compartments. This will facilitate particle-flow (PF) calorimetry, where the fine structure of showers can be measured and used to enhance pileup rejection and particle identification, whilst still achieving good energy resolution. The CE-E and a large fraction of CE-H will be based on hexagonal silicon sensors of $0.5-1{\mathrm{\text{cm}}}^2$ cell size, with the remainder of the CE-H based on highly-segmented scintillators with SiPM readout. The intrinsic high-precision timing capabilities of the silicon sensors will add an extra dimension to event reconstruction, especially in terms of pileup rejection. An overview of the HGCAL project is presented in this paper.

The Jiangmen Underground Neutrino Observatory (JUNO) is a multiple-purpose neutrino experiment with a 20 kiloton liquid scintillator (LS) detector at a depth of 700 meters. With about 18,000 20" photomultiplier tubes (PMTs) installed on the surface of a 35.4 meter diameter central detector, providing more than 75% coverage, JUNO aims for an unprecedented 3% energy resolution at 1 MeV. In order to achieve this energy resolution which needs a 1% precision in the absolute energy scale, the control of the energy response systematics is crucial. The single channel charge measurement is challenging in such a large detector, as the number of photoelectrons in each PMT can differ by two orders of magnitude depending on the event’s position and energy. Second system of PMTs consisting of 25,000 3" PMTs placed in the space between the large PMTs and operating primarily in photon-counting mode will allow to calibrate the energy response of the large PMTs and to improve the physics of JUNO in several ways. The motivation for the double-calorimetry, as well as its benefits and implementation in JUNO will be discussed in this proceeding.

Natural gas consists mainly of methane (CH₄) and ethane (CH₃CH₃) and other hydrocarbons in small quantities. Depending on the source it may also contain CO₂, nitrogen (N₂), hydrogen sulfide (H₂S) and helium (He). It is very abundant and its combustion contributes to the increase of the CO₂ content in the biosphere. Natural gas is a non-renewable fuel (Section 5.1). It is widely used to produce electricity, heat, chemicals including hydrogen, and hydrocarbons (liquid fuels) and as a fuel for motor vehicles…

The Large Hadron Collider (LHC) is the new CERN accelerator that will provide proton proton collisions at . It will have two dedicated experiments: Alice, to study heavy ion collisions, and LHCb, to study b physics, and two general purpose experiments: Atlas and CMS. The LHC is an explorative machine to search for the Higgs boson and physics beyond the Standard Model. Calorimeters play a crucial role in these searches. In particular the electromagnetic calorimeters are fundamental in the search for the Higgs boson, depending on the mass range, either in the two photon decay channel or in the four leptons channel. Hadron calorimeters are important for super-symmetric particles searches where jets and missing transverse energy are expected. We present a review of the LHC experiments calorimeters and their expected performance.

The CMS HF Calorimeter was the first detector to be lowered into the cavern at UX5. It was placed in the garage position during the lowering of the rest of the big CMS pieces. The commissioning of the hardware parts is continuing, especially integrating the HF and completing the monitoring systems, such as, online laser, LED and radioactive source monitoring. Also a special monitor system for the radiation damage (raddam) of the quartz fibers is being implemented. Calibration measurements of the calorimeter had already started even before the lowering. Progress in the calibration work and current plans for the HF calorimeter during the low luminosity run will be summarized.

The Large Hadron Collider at CERN will allow the study of pp interactions at a center of mass energy of 14 TeV. The main physics goals of the Compact Muon Solenoid (CMS) experiment are the discovery of the Higgs boson and the search for new physics. Experimental conditions and physics goals set demanding constraints on the Electromagnetic Calorimeter (ECAL), made of about 76000 Lead Tungstate scintillating crystals, to be able to achieve a high precision in photon and electron energy measurement. ECAL performance has been studied using an electron test beam, before final commissioning in the experiment. The most relevant results are presented.

The CMS Electromagnetic Calorimeter (ECAL) calibration foresees dedicated protocols both before and during the data taking. Up to now test beam electrons and cosmic muons have been used to precalibrate ECAL. During the summer 2006, nine ECAL supermodules have been exposed to a high energy electron beam at the CERN SPS north area facility and the intercalibration coefficients of the 1700 channels have been measured for each supermodule. The reproducibility of the intercalibration has been tested by measuring a supermodule twice. Different calibration methods based either on single crystals or on matrices of crystals energy reconstruction have been used. The intercalibration coefficients obtained have also been compared with those calculated by means of the cosmic ray muons.

The CMS experiment at the CERN Large Hadron Collider has placed great emphasis on precise calorimetry. The electromagnetic calorimeter (ECAL) contains 75000 scintillating lead tungstate crystals that are read out using sophisticated electronics; this paper describes these technologies and how they were implemented in the calorimeter. The results of pre-calibration measurements for the detector modules are detailed. Installation of the ECAL into the underground cavern has commenced and the commissioning process and its status are discussed. The experiment is scheduled to start in 2008 and prospects for the first year of operation and running are given.

In recent years Silicon Photomultipliers (SiPMs) have been proposed as a new type of readout system for scintillating detectors in many experiments. SiPMs consist of a matrix of parallel-connected silicon micro-pixels, which are independent photon counters working in limited Geiger mode with very high gain (~10⁶). This contribution presents the use of an array of SiPMs (manufactured by FBK-irst) for the readout of a shashlik calorimeter composed by lead and scintillator tiles for a total of ~23 X₀; the scintillator light is carried out by 64 WLS fibers (4 fibers per SiPM). The performances of the calorimeter in terms of linearity and energy resolution have been tested in a beam test with charged particles (e^±, muons and pions) with a momentum up to 6 GeV/c at the CERN PS T10 line.

In 2004 at the ATLAS combined test beam, one slice of the ATLAS barrel detector (including an Inner Detector set-up and the Liquid Argon (LAr) calorimeter) was exposed to particles from the H8 SPS beam line at CERN. It was the first occasion to test the combined electron performance of ATLAS. This presentation will show the results obtained for the electromagnetic performance of the LAr calorimeter (linearity, uniformity and resolution). Results obtained with a very low energy set-up (electron energies down to 1 GeV) will be presented validating the LAr electromagnetic energy reconstruction down to very low energies. Results obtained for the E/p ratio and a way how to extract scale parameters will be shown. Studies on Bremstrahlungs-recovery algorithms relying on the LAr calorimeter will be discussed on the basis of results obtained in the testbeam.

The HF Calorimeter in the CMS Detector was commissioned and ready for data taking in 2008. Final commissioning tasks done in 2008 will be summarized. Some results from the splash event when the LHC was turned on will be presented. Anomalous events seen in the HF-PMTs have been understood and proposed methods to resolve this problem are explained. The HF readiness for the data taking in 2009 will be also discussed.

The angular coverage extension of the KLOE-2 electromagnetic calorimeter, from a polar angle of 20º down to 8º, will increase the multiphoton detection capability of the experiment enhancing the search reach for rare kaon, η and η' prompt decay channels. The basic layout of the calorimeter extension consists of two small barrels of LYSO crystals readout with APD photosensors aiming to achieve a timing resolution between 300 and 500 ps for 20 MeV photons. The first test of a (5.5 × 6 × 13) cm³ prototype for such a detector was carried out at the Beam Test Facility of Laboratori Nazionali di Frascati of INFN and we present here the first results.