V. Rusinov

DANSS is a highly segmented 1~m${}^3$ plastic scintillator detector. Its 2500 one meter long scintillator strips have a Gd-loaded reflective cover. The DANSS detector is placed under an industrial 3.1~$\mathrm{GW_{th}}$ reactor of the Kalinin Nuclear Power Plant 350~km NW from Moscow. The distance to the core is varied on-line from 10.7~m to 12.7~m. The reactor building provides about 50~m water-equivalent shielding against the cosmic background. DANSS detects almost 5000 $\widetilde\nu_e$ per day at the closest position with the cosmic background less than 3$\%$. The inverse beta decay process is used to detect $\widetilde\nu_e$. Sterile neutrinos are searched for assuming the $4\nu$ model (3 active and 1 sterile $\nu$). The exclusion area in the $\Delta m_{14}^2,\sin^22\theta_{14}$ plane is obtained using a ratio of positron energy spectra collected at different distances. Therefore results do not depend on the shape and normalization of the reactor $\widetilde\nu_e$ spectrum, as well as on the detector efficiency. Results are based on 966 thousand antineutrino events collected at 3 distances from the reactor core. The excluded area covers a wide range of the sterile neutrino parameters up to $\sin^22\theta_{14}<0.01$ in the most sensitive region.

The state of art of the Silicon Photomultipliers (SiPM's)—their features, possibilities and applications—is given. The significant progress of this novel technique of photo detection is described and discussed.

The DANSS project is aimed at creating a relatively compact neutrino spectrometer which does not contain any flammable or other dangerous liquids and may therefore be located very close to the core of an industrial power reactor. As a result, it is expected that high neutrino flux would provide about 15,000 IBD interactions per day in the detector with a sensitive volume of 1 m3. High segmentation of the plastic scintillator will allow to suppress a background down to a ∼1% level. Numerous tests performed with a simplified pilot prototype DANSSino under a 3 GWth reactor of the Kalinin NPP have demonstrated operability of the chosen design. The DANSS detector surrounded with a composite shield is movable by means of a special lifting gear, varying the distance to the reactor core in a range from 10 m to 12 m. Due to this feature, it could be used not only for the reactor monitoring, but also for fundamental research including short-range neutrino oscillations to the sterile state. Supposing one-year measurement, the sensitivity to the oscillation parameters is expected to reach a level of sin2(2θnew) ∼ 5 × 10−3 with Δ m2 ⊂ (0.02–5.0) eV2.

We present results on calibration runs performed with pions at the CERN SPS for different modules of the H 1 liquid argon calorimeter which consists of an electromagnetic section with lead absorbers and a hadronic section with steel absorbers. The data cover an energy range from 3.7 to 205 GeV. Detailed comparisons of the data and simulation with GHEISHA 8 in the framework of GEANT 3.14 are presented. The measured pion induced shower profiles are well described by the simulation. The total signal of pions on an energy scale determined from electron measurements is reproduced to better than 3% in various module configurations. After application of weighting functions, determined from Monte Carlo data and needed to achieve compensation, the reconstructed measured energies agree with simulation to about 3%. The energies of hadronic showers are reconstructed with a resolution of about 50%√E ⨸ 2%. This result is achieved by inclusion of signals from an iron streamer tube tail catcher behind the liquid argon stacks.

We report on the design, construction and performance of a prototype for a high-granularity tile hadronic calorimeter for a future international linear collider detector. Scintillating tiles are read out via wavelength-shifting fibers that guide the scintillation light to a novel photodetector, the silicon photomultiplier. A prototype has been tested using a positron test beam at DESY. The results are compared with a reference prototype calorimeter equipped with multichannel vacuum photomultipliers. Detector calibration, noise, linearity and stability are discussed, and the energy response in a 1–6 GeV positron beam is compared with simulations. The present results demonstrate that the silicon photomultiplier is well-suited as photodetectors in calorimeters and thus has been selected for the construction of a 1m3 calorimeter prototype to operate in hadron beams.

The energy resolution of a highly granular 1 m3 analogue scintillator-steel hadronic calorimeter is studied using charged pions with energies from 10 GeV to 80 GeV at the CERN SPS. The energy resolution for single hadrons is determined to be approximately 58%/sqrt(E/GeV}. This resolution is improved to approximately 45%/sqrt(E/GeV) with software compensation techniques. These techniques take advantage of the event-by-event information about the substructure of hadronic showers which is provided by the imaging capabilities of the calorimeter. The energy reconstruction is improved either with corrections based on the local energy density or by applying a single correction factor to the event energy sum derived from a global measure of the shower energy density. The application of the compensation algorithms to Geant4 simulations yield resolution improvements comparable to those observed for real data.

The performances of the H1 liquid argon calorimeter modules for the energy measurements and identification of electrons are studied with test data taken at CERN in the energy range 5 to 166 GeV. Various electron identification estimators exploiting global or detailed shower characteristics are studied and compared. The usage of impact position measurements is also discussed. A best combination of robust shower estimators leads typically to π-misidentification probabilities in the range 1.5 to 5.0 × 10−3 at 30 GeV for 95% electron detection efficiency. This further reduces to ∼ 10−4 for these pions to be misidentified as electrons below 25 GeV.

The electromagnetic calorimeter of the HERA-B experiment built at the HERA proton accelerator at DESY (Hamburg) is described. The construction characteristics of the detector, of the related front-end, readout, trigger and service electronics are discussed together with the constraints and the motivations which inspired the design philosophy. The detector performance are presented as obtained from the analysis of the data acquired during the HERA-B running period, including calibration procedures and achievements and the electron identification capability exploiting a method, proposed here for the first time, based on the observation of the associated bremsstrahlung γ. Finally, some observed physical signals and a short overview of the main obtained physics results are presented.

DANSSino is a reduced pilot version of a solid-state detector of reactor antineutrinos (to be created within the DANSS project and installed under the industrial 3 GWth reactor of the Kalinin Nuclear Power Plant—KNPP). Numerous tests performed at a distance of 11 m from the reactor core demonstrate operability of the chosen design and reveal the main sources of the background. In spite of its small size (20 × 20 × 100 cm3), the pilot detector turned out to be quite sensitive to reactor antineutrinos, detecting about 70 IBD events per day with the signal-to-background ratio about unity.

Calorimeters with a high granularity are a fundamental requirement of the Particle Flow paradigm. This paper focuses on the prototype of a hadron calorimeter with analog readout, consisting of thirty-eight scintillator layers alternating with steel absorber planes. The scintillator plates are finely segmented into tiles individually read out via Silicon Photomultipliers. The presented results are based on data collected with pion beams in the energy range from 8 GeV to 100 GeV. The fine segmentation of the sensitive layers and the high sampling frequency allow for an excellent reconstruction of the spatial development of hadronic showers. A comparison between data and Monte Carlo simulations is presented, concerning both the longitudinal and lateral development of hadronic showers and the global response of the calorimeter. The performance of several GEANT4 physics lists with respect to these observables is evaluated.

We present measurements of the reduction of light output by plastic scintillators irradiated in the CMS detector during the 8 TeV run of the Large Hadron Collider and show that they indicate a strong dose rate effect. The damage for a given dose is larger for lower dose rate exposures. The results agree with previous measurements of dose rate effects, but are stronger due to the very low dose rates probed. We show that the scaling with dose rate is consistent with that expected from diffusion effects.

A neural network for software compensation was developed for the highly granular CALICE Analogue Hadronic Calorimeter (AHCAL). The neural network uses spatial and temporal event information from the AHCAL and energy information, which is expected to improve sensitivity to shower development and the neutron fraction of the hadron shower. The neural network method produced a depth-dependent energy weighting and a time-dependent threshold for enhancing energy deposits consistent with the timescale of evaporation neutrons. Additionally, it was observed to learn an energy-weighting indicative of longitudinal leakage correction. In addition, the method produced a linear detector response and outperformed a published control method regarding resolution for every particle energy studied.

Abstract DANSS is a spectrometer for reactor antineutrinos based on plastic scintillator. The sensitive volume of the detector is made of 2500 polystyrene based scintillator plates with wavelength shifting (WLS) fiber readout (strips). We present a study of the light yield of strips during 6.5 years of DANSS continuous running. Overall ageing at the rate 0.55 ± 0.05 (syst.) % per year is observed that is considerably smaller than in other similar experiments. We also observe the WLS fiber attenuation length shortening at the rate 0.26 ± 0.04(stat.) % per year.

A new KL0 and muon detector based on scintillators will be used for the endcap regions in the Belle II experiment, currently under construction. The increased luminosity of the e+e− SuperKEKB collider entails challenging detector requirements. We demonstrate that relatively inexpensive polystyrene scintillator strips with wavelength shifting fibers ensure a sufficient light yield at the Silicon PhotoMultiplier (SiPM) photodetector, are robust and provide improved physics performance for the Belle II experiment compared to its predecessor, Belle.

The performance of the 200×2.5×1cm3 plastic scintillator strip with wavelength shifting fiber read out by two novel photodetectors called Silicon PhotoMultipliers (SiPMs) is discussed. The advantages of SiPM relative to the traditional multichannel photomultiplier are shown. Light yield and light attenuation measurements are presented. This technique can be used in muon or calorimeter systems.

This paper presents results obtained with the combined CALICE Scintillator Electromagnetic Calorimeter, Analogue Hadronic Calorimeter and Tail Catcher & Muon Tracker, three high granularity scintillator-silicon photomultiplier calorimeter prototypes. The response of the system to pions with momenta between 4 GeV/c and 32 GeV/c is analysed, including the average energy response, resolution, and longitudinal shower profiles. Two techniques are applied to reconstruct the initial particle energy from the measured energy depositions; a standard energy reconstruction which is linear in the measured depositions and a software compensation technique based on reweighting individually measured depositions according to their hit energy. The results are compared to predictions of the GEANT 4 physics lists QGSP_BERT_HP and FTFP_BERT_HP.

Wavelength shifting fibers are widely used for light collection from scintillation counters, which allow connection of various scintillation planes to relatively small photocathodes of photodetectors and especially tiny photocathodes of silicon photo-multipliers. In October 2020 Kuraray announced production of a new branch of faster fibers. We performed a comparison of the new fiber YS-2 to a mature Y-11. The fiber YS-2 demonstrated decay time nearly two times shorter than that of Y-11: $\approx$4.0 ns versus $\approx$7.4 ns. At the same time its light yield and attenuation length are as good as of Y-11, which makes YS-2 a good choice for timing scintillation detectors.

The spatial development of hadronic showers in the CALICE scintillator-steel analogue hadron calorimeter is studied using test beam data collected at CERN and FNAL for single positive pions and protons with initial momenta in the range of 10–80 GeV/c. Both longitudinal and radial development of hadron showers are parametrised with two-component functions. The parametrisation is fit to test beam data and simulations using the QGSP_BERT and FTFP_BERT physics lists from GEANT4 version 9.6. The parameters extracted from data and simulated samples are compared for the two types of hadrons. The response to pions and the ratio of the non-electromagnetic to the electromagnetic calorimeter response, h/e, are estimated using the extrapolation and decomposition of the longitudinal profiles.

We report upon the performance of an analog hadron calorimeter prototype, where plastic scintillator tiles are read out with wavelength-shifting fibers coupled to avalanche photodiodes. This prototype configuration has been tested using a positron beam at DESY with energies between 1 and 6 GeV. We present different detector calibration methods, show measurements for noise, linearity, and energy resolution and discuss gain monitoring with an LED system. The results are in good agreement with our simulation studies and previous measurements using silicon photomultiplier readout.

DANSSino is a simplified pilot version of a solid-state detector of reactor antineutrino (it is being created within the DANSS project and will be installed close to an industrial nuclear power reactor). Numerous tests performed under a 3 GW(th) reactor of the Kalinin NPP at a distance of 11 m from the core demonstrate operability of the chosen design and reveal the main sources of the background. In spite of its small size (20x20x100 ccm), the pilot detector turned out to be quite sensitive to reactor neutrinos, detecting about 70 IBD events per day with the signal-to-background ratio about unity.

Abstract The scintillator tiles with direct readout by silicon photomultipliers (SiPM) have been studied. The SiPM is placed inside the dimple machined in the center of the big face of 30×30×3 mm3 tile. The different dimple geometries were studied. The tiles with the optimal dimple design show the uniformity of response comparable to the tiles with fiber readout. The direct-readout approach provides a reasonable way for the construction of supermultichannel calorimeters.

Plastic scintillators are often used as detectors in High Energy Physics (HEP), but have insufficient radiation hardness. Organization of better light collection inside a single detector may prolong operation life of scintillators. A finger-strip plastic scintillator option has many advantages to keep the excellent detector performance at high luminosity. Measurements assigned to show an advantage of a stripped detector vs. the un-stripped one in the range of increased absorbed doses and the smallest dose rates have been performed. This method has proved to be a good upgrade strategy.

Abstract The DANSS detector (Alekseev et al. in JINST 11:P11011, 2016) is located directly below a commercial reactor core at the Kalinin Nuclear Power Plant. Such a position provides an overburden about 50 m.w.e. in vertical direction. In terms of the cosmic rays it occupies an intermediate position between surface and underground detectors. The sensitive volume of the detector is a cubic meter of plastic scintillator with fine segmentation and combined PMT and SiPM readout, surrounded by multilayer passive and active shielding. The detector can reconstruct muon tracks passing through its sensitive volume. The main physics goal of the DANSS experiment implies the antineutrino spectra measurements at various distances from the source. This is achieved by means of a lifting platform so that the data is taken in three positions – 10.9, 11.9 and 12.9 meters from the reactor core. The muon data were collected for nearly four calendar years. The overburden parameters $$\langle E_{thr}\cos \theta \rangle $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mo>⟨</mml:mo> <mml:msub> <mml:mi>E</mml:mi> <mml:mrow> <mml:mi>thr</mml:mi> </mml:mrow> </mml:msub> <mml:mo>cos</mml:mo> <mml:mi>θ</mml:mi> <mml:mo>⟩</mml:mo> </mml:mrow> </mml:math> and $$\langle E_{thr} \rangle $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mo>⟨</mml:mo> <mml:msub> <mml:mi>E</mml:mi> <mml:mrow> <mml:mi>thr</mml:mi> </mml:mrow> </mml:msub> <mml:mo>⟩</mml:mo> </mml:mrow> </mml:math> , as well as the temperature and barometric correlation coefficients are evaluated separately for the three detector positions and, in each position, in three ranges of the zenith angle – for nearly vertical muons with $$\cos \theta &gt;0.9$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mo>cos</mml:mo> <mml:mi>θ</mml:mi> <mml:mo>&gt;</mml:mo> <mml:mn>0.9</mml:mn> </mml:mrow> </mml:math> , for nearly horizontal muons with $$\cos \theta &lt;0.36$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mo>cos</mml:mo> <mml:mi>θ</mml:mi> <mml:mo>&lt;</mml:mo> <mml:mn>0.36</mml:mn> </mml:mrow> </mml:math> , and for the whole upper hemisphere.

Abstract Calorimeters based on silicon core fibres embedded into an absorber have been simulated by combining the GEANT 3.16 package and a proprietary routine describing Cherenkov photon production in optical fibres. The good agreement between simulation results and experimental data allows to study, with a high degree of confidence, the design of a prototype hadronic detector and of different calorimeter configurations to cover the very forward regions of an LHC experiment.

The appearance of new photo-sensors, SiPMs, gives a new life to detectors based on solid scintillators. All the advantages of SiPMs have been demonstrated with the construction of the full-scale hadron calorimeter prototype by the CALICE collaboration. New applications are made possible by using strips as the detector element and SiPMs of new generation. Two examples are discussed: a TOF system for antineutron detection for the CMD-3 experiment at VLEPP-2000; and an antineutrino detector for on-line monitoring of nuclear power plants. For the first case, the timing properties of a strip-WLS fiber-SiPM system have been studied. A time resolution of 0.8 ns could be achieved. For the second case, the capability of antineutrino scintillator detector to moderate neutrons is used and discussed.

A detector of the reactor antineutrino based on a cubic meter of plastic scintillator is installed below 3.1 GW industrial reactor. The detector is placed on a movable platform which allows to change the distance to the reactor core center in the range 10.7-12.7 m. 2500 scintillator strips are read out individually by SiPMs and in groups of 50 by PMTs. In addition to the overburden by the reactor (50 m w.e.) the detector has multilayer passive shielding and active muon veto.

The DANSS project is aimed at creating a relatively compact neutrino spectrometer which does not contain any flammable or other dangerous liquids and may therefore be located very close to the core of an industrial power reactor. As a result, it is expected that high neutrino flux would provide about 15,000 IBD interactions per day in the detector with a sensitive volume of 1 m$^3$. High segmentation of the plastic scintillator will allow to suppress a background down to a 1% level. Numerous tests performed with a simplified pilot prototype DANSSino under a 3 GW$_{th}$ reactor of the Kalinin NPP have demonstrated operability of the chosen design. The DANSS detector surrounded with a composite shield is movable by means of a special lifting gear, varying the distance to the reactor core in a range from 10 m to 12 m. Due to this feature, it could be used not only for the reactor monitoring, but also for fundamental research including short-range neutrino oscillations to the sterile state. Supposing one-year measurement, the sensitivity to the oscillation parameters is expected to reach a level of $sin^2(2\theta)$ ~ 0.005 with $\Delta m^2 \subset (0.02-5.0)$ eV$^2$.

Results on the light output of different kinds of silica fibres and on energy resolution and electromagnetic shower dimensions in small lead/quartz fibres calorimeter prototypes are presented, together with a possible design of a very forward calorimeter for LHC.

Upgrade of the Time of Flight (TOF) system of the CMD-3 detector is described. The TOF is located inside the narrow gap between two layers of the cylindrical calorimeter based on the liquid Xe and CsI crystals. The TOF system is made from thin plates of plastic scintillator and is intended for measuring the time of flight of particles through the detector, in particular to detect products of antineutron annihilations in the calorimeters. Due to low velocities of antineutrons, the average times of annihilation in the calorimeters have a typical delay time about 4–10 ns with respect to the beam collision.

A small quartz fiber calorimeter prototype with copper absorber has been assembled and tested at ITEP as a first test of a “0 degree” component of the RD-40 R&D program. Calibration and monitoring of each tower response was performed using the positions of single photoelectron peaks as well as the response to minimum ionizing particles incident at an angle of 45°. The response of the prototype to 4 GeV electrons as a function of beam angle with respect to the quartz fibers was studied in the range from 0° to 90°. The test results are compared to the GEANT based Monte Carlo (MC) simulations.

DANSS is a spectrometer of reactor antineutrino based on plastic scintillator. The sensitive volume of the detector is made of 2500 polystyrene based scintillator plates with wavelength shifting (WLS) fiber readout (strips). We present a study of the strips light yield during 6.5 years of DANSS continuous running. Overall ageing at the rate $0.55 \pm 0.05(syst.)$ % per year is observed that is considerably smaller than in other similar experiments. We also observe the WLS fiber attenuation length shortening at the rate $0.26 \pm 0.04(stat.)$ % per year.

A high granularity scintillator hadronic calorimeter prototype is described. The calorimeter is based on a novel photodetector – Silicon Photo-Multiplier (SiPM). The main parameters of SiPM are discussed as well as readout cell construction and optimization. The experience with a small prototype production and testing is described. A new 8 k channel prototype is being manufactured now.

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Abstract DANSS is a one cubic meter plastic scintillator detector with a primary goal of sterile neutrino searches at a commercial nuclear reactor. Due to its highly advantageous location, fine segmentation and ability to change the distance to the neutrino production origin, DANSS is ahead of many similar experiments around the world in terms of the counting rate, signal to background ratio and sterile neutrino exclusion regions. Yet a moderate energy resolution of the detector prevents further progress in the physics program. The main challenge of the planned upgrade is to achieve an energy resolution of 12% at 1 MeV. The new design of the main sensitive element — the plastic scintillation strip — is the most important step forward. The strip prototypes were manufactured and tested at the pion beam of the PNPI synchrocyclotron. More than twice higher light output together with fairly flat detector response uniformity, longitudinal timing information and other optimizations will help to reach the upgrade goal. This paper discusses the drawbacks of the current strip version, outlines the new features of the proposed upgrade, describes the beam test procedure and presents the test results reflecting the advantages of the new strip design in comparison with the current version.

The abilities of the computer code CASCADE developed in Dubna are illustrated, using as an example results of a simulation of γ-radioactivity, generated in Al, Ti and Fe targets under high-energy proton irradiation. The calculated results are compared with the experimental data obtained at energies of 1.0–1.3 GeV. The depth distribution of radionuclides produced in aluminium and iron targets is discussed. The discrepancy between the experimental and calculated data is about 20 to 30% on average.

The design of the phototube power supply for the HERA-B Electromagnetic Calorimeter is presented. A choice of the solution on the basis of the Cockcroft–Walton voltage multiplier is validated. Schematics developed are discussed. A special section describes the behaviour of the crucial components under irradiation since radiation tolerance becomes one of the most important items in the severe HERA-B radiation environment. Finally, performance achieved is presented.

The results of the research in the field of neutrino physics obtained at Kalinin nuclear power plant during 15 years are presented. The investigations were performed in two directions. The first one includes GEMMA I and GEMMA II experiments for the search of the neutrino magnetic moment, where the best result in the world on the value of the upper limit of this quantity was obtained. The second direction is tied with the measurements by a solid scintillator detector DANSS designed for remote on-line diagnostics of nuclear reactor parameters and search for short range neutrino oscillations. DANSS is now installed at the Kalinin Nuclear Power Plant under the 4-th unit on a movable platform. Measurements of the antineutrino flux demonstrated that the detector is capable to reflect the reactor thermal power with an accuracy of about 1.5% in one day. Investigations of the neutrino flux and their energy spectrum at different distances allowed to study a large fraction of a sterile neutrino parameter space indicated by recent experiments and perform the reanalysis of the reactor neutrino fluxes. Status of the short range oscillation experiment is presented together with some preliminary results based on about 170 days of active data taking during the first year of operation.

We study the light output, light collection efficiency and signal timing of a variety of organic scintillators that are being considered for the upgrade of the hadronic calorimeter of the CMS detector. The experimental data are collected at the H2 test-beam area at CERN, using a 150 GeV muon beam. In particular, we investigate the usage of over-doped and green-emitting plastic scintillators, two solutions that have not been extensively considered. We present a study of the energy distribution in plastic-scintillator tiles, the hit efficiency as a function of the hit position, and a study of the signal timing for blue and green scintillators.

This paper presents results obtained with the combined CALICE Scintillator Electromagnetic Calorimeter, Analogue Hadronic Calorimeter and Tail Catcher & Muon Tracker, three high granularity scintillator-SiPM calorimeter prototypes. The response of the system to pions with momenta between 4 GeV/c and 32 GeV/c is analysed, including the energy response, resolution, and longitudinal shower profiles. The results of a software compensation technique based on weighting according to hit energy are compared to those of a standard linear energy reconstruction. The results are compared to predictions of the GEANT4 physics lists QGSP_BERT_HP and FTFP_BERT_HP.

DANSS is a one cubic meter highly segmented solid scintillator detector.It consists of 2500 scintillator strips (100×4×1 cm 3 ), covered with gadolinium loaded reflective coating and read out with SiPMs via wave length shifting fibers.Groups of 50 strips are also read out by conventional PMTs.DANSS is placed under a 3 GW industrial reactor at the Kalinin NPP (Russia) on a movable platform.The distance from the reactor core center can be changed from 10.7 m to 12.7 m.The reactor building provides about 50 m.w.e.shielding against cosmic backgrounds, which reduces the background drastically.The inverse beta decay (IBD) process is used to detect antineutrinos.DANSS detects about 5000 IBD events per day with the background from cosmic muons of about 3%.The dependence of the antineutrino spectrum on the fuel composition is clearly observed.Sterile neutrinos are searched for assuming a 4 neutrino model (3 active and 1 sterile neutrino).The exclusion area in the sterile neutrino parameter plane is obtained using a ratio of positron energy spectra collected at different distances.Therefore, the results do not depend on the shape and normalization of the reactor antineutrino spectrum, as well as on the detector efficiency.Results are based on 1.088 million antineutrino events.The excluded area covers a wide range of the sterile neutrino parameters up to sin 2 2θ 14 < 0.01 in the most sensitive region.The Reactor Antineutrino Anomaly optimum point is excluded at the confidence level higher than 5σ .

Two CMS Endcap hadron calorimeters (HE) have been in operation for several years and contributed substantially to the success of the CMS Physics Program. The HE calorimeter suffered more from the radiation than it had been anticipated because of rapid degradation of scintillator segments (tiles) which have a high radiation flux of secondary particles. Some investigations of scintillators have shown that the degradation of plastic scintillator increases significantly at low dose rates. A proposal to upgrade up-grade the HE calorimeter has been prepared to provide a solution for survivability of the future LHC at higher luminosity and higher energy. A finger-strip plastic scintillator option has many advantages and is a lower cost alternative to keep the excellent HE performance at high luminosity. Measurements have been performed and this method has proved to be a good upgrade strategy.

The research of the light yield from the scintillator tiles with direct readout by silicon photomultipliers (SiPM) has been performed. The tile size is 30 x 30 x 3 mm3 as planned for the AHCAL of the ILD at the ILC. The different tile geometries were studied. The uniformity of light yield has been optimized and one geometry has been selected. The results are compared to the studies on the same topic, performed by another groups.

The Phase I upgrade of the CMS Hadron Endcap Calorimeters consists of new photodetectors (Silicon Photomultipliers in place of Hybrid Photo-Diodes) and front-end electronics. The upgrade will eliminate the noise and the calibration drift of the Hybrid Photo-Diodes and enable the mitigation of the radiation damage of the scintillators and the wavelength shifting fibers with a larger spectral acceptance of the Silicon Photomultipliers. The upgrade also includes increased longitudinal segmentation of the calorimeter readout, which allows pile-up mitigation and recalibration due to depth-dependent radiation damage. As a realistic operational test, the responses of the Hadron Endcap Calorimeter wedges were calibrated with a 60Co radioactive source with upgrade electronics. The test successfully established the procedure for future source calibrations of the Hadron Endcap Calorimeters. Here we describe the instrumentation details and the operational experiences related to the sourcing test.

DANSS is a highly segmented plastic scintillator detector, which uses scintillator strips with a Gd-loaded reflective cover to detect reactor antineutrino by inverse beta-decay. Light is collected with wave length shifting fibers (3 per strip) placed in grooves. Therefore the distribution of light output could be significantly non-uniform. Transverse profile of light output was studied in ITEP at a test bench consisting of proportional chambers and scintillator strips. Tracks of cosmic particles, which crossed chambers, were reconstructed with high accuracy, whereby transverse profiles of light output were built with step 1 mm for six scintillator strips. This result is important for calibration of DANSS and the method could be useful in constructing similar detectors.

We report the results of the tests of 150 detectors consisting of a scintillator strip and a wavelength-shifting fiber, read out by a metal-resistor silicon avalanche photodiode operating in the Geiger mode (MRS APD). Using weak flashes of a Light Emitting Diode we clearly see individual photoelectrons in the amplitude spectra of all MRS APDs. Based on these spectra we determine the gain, the relative quantum efficiency and the cross-talk of the MRS APDs. Using cosmic rays we measure the light yield, the efficiency, the response uniformity and the time resolution of the strips. The first results of the radiation hardness study using a proton beam are presented. The strips are to be installed at the Belle detector as a prototype of the future muon system for the Super B-factory.

Measurements of reactor antineutrino play an important role in the efforts at the frontier of the modern physics. The DANSS collaboration presents preliminary results of a one year run with a cubic meter solid state detector placed below 3.1 GW industrial light water reactor. The experiment is sensitive to sterile neutrino in the most interesting region of mixing parameter space. 2500 scintillation strips of the sensitive volume of the detector have multilayer passive shielding of copper, lead and borated polyethylene and active muon veto. Detector position below the reactor gives an advantage of overburden about 50 m of water equivalent providing factor of six in cosmic muon suppression and eliminating fast neutrons.The detector is placed on a vertically movable platform which allows to change the distance to the reactor core center in the range 10.7-12.7 m within a few minutes. The strips are read out individually by SiPMs and in groups of 50 by PMTs. 5000 inverse beta-decay events per day are collected in the fiducial volume, which is 78% of the whole detector, at the position closest to the reactor. Overburden, active veto and good segmentation of the detector result in an excellent signal to background ratio. The talk is dedicated to the data analysis and preliminary results. The experiment status is also presented.

In this paper, the isoefficiency of MPP systems and heterogeneous CPU-GPU systems on the problem of discrete Fourier transform is considered. The development of parallel applications as its goal can not only reduce execution time, but also provide opportunities to solve problems of a larger dimension. The peculiarity of algorithm parallelization includes the efficient use of hardware while increasing the dimension of the problem is an important characteristic of parallel computing. However, currently heterogeneous systems have not been researched extensively to determine isoefficiency characteristics and build application-specific systems around said method, although there are articles that show potential using isoefficiency to design the system and using heterogeneous approach to accelerate performance of different tasks. Discrete Fourier Transform algorithm lets build systems that discretize analogue and digital signals and it can serve as a benchmark to test different systems. Algorithms suited for MPP systems can use analytical approach to find out issoefficiency function and to determine how scaling the system or changing the size of the task will change its performance metrics. One of the most popular approaches to linking up processing units in MPP systems is using hypercube topology. MPP system that is connected using this topology will be analyzed. CPU-GPU heterogeneous system will be analyzed using an approach based on polynomial regression. Due to the nature of heterogeneous systems, analytic approach used in MPP system is impossible. Predictive model based on polynomial regression will use modelling results from using CPU and GPU separately to estimate how much time it will take for heterogeneous system to finish the task. To ensure accuracy of the experiment, several systems will be used to model the task. Using this approach, resulting issoefficient heterogeneous system will be analyzed using performance metrics s

The differential cross sections for d knockout from Be, Al, Cu, and Au and for t knockout from Be by protons with a momentum of 2.14 GeV/c at an angle of 62 mrad have been measured at momenta higher than the primary momentum. The differential cross sections for quasifree reactions are determined.

Experimental data are reported on inclusive ..pi../sup -/ production at an angle of 62 mrad in the laboratory frame in proton--nucleus interactions at proton momenta of 3.95, 6.7, 8.8, and 9.7 GeV/c and on the inclusive production of ..pi../sup -/ mesons and protons at an angle of 188 mrad in proton--nucleus interactions at 9 GeV/c. The possibility of determining the cross sections for the interaction of ''young'' pions with the nucleons of the nucleus from the inclusive data is analyzed.

Experimental data have been obtained on the inclusive production of protons in pA interactions at an angle 62 mrad at initial momenta 4.0, 6.6, and 9.5 GeV/c. The A and t dependences of the quasielastic scattering of protons by nuclei are discussed.

Proton extraction from a synchrotron by means of an internal target of magnetized iron is described. The particles that are aimed at the target pass directly through it and are deflected by the internal magnetic field of the target in the extraction direction. The general properties of magnetic targets are examined theoretically and a specific devices and results of its testing are described.