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In this paper we present the results of applying the new approach for calculating coincidence summing effects. The application of analytical approaches to coincidence summing effects makes it possible to predict all summation peaks that occur in the spectrum. Accordingly, based on the value of the peak area in the spectrum and knowledge of probability transitions between excited states of a nucleus, it is possible to determine the efficiency of detection and activity of radioactive sources. This method is successfully applied to the decay of the radionuclide europium 152 Eu. It provides a detailed description of the method of forming the matrix corresponding to the final result – determined activities and the efficiency of detection. The importance of the new method is that it allows us to determine the efficiency of detection and activity of radioactive sources directly without calibration of the detector, which is very important in metrology of radionuclides. [ABSTRACT FROM AUTHOR]

Evaluation of the complete decay scheme and data for 125 Sb/ 125m Te decay to nuclear levels in 125 Te is presented in this report; literature data available up to June 2015 are included. The Limitation of Relative Statistical Weight Method (LRSW) was applied to average numbers throughout the evaluation. The uncertainty assigned to the average value was always greater than or equal to the smallest uncertainty of the values used to calculate the average. The half-life has been determined to be 1007.4±0.3 days. All known measured γ-ray absolute or relative intensities have been examined; the γ-ray emission probability of the reference γ-ray line of 427.874 keV is recommended to be 29.54±0.10%. The theoretical internal conversion coefficients and their uncertainties were used to obtain the complete decay scheme intensity balance. The values of other decay characteristics were calculated using the ENSDF analysis program. Finally the updated decay scheme for 125 Sb is presented. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents several mechanisms expected to be responsible for nuclear excitation in laser-heated plasma. Attempts to detect such processes in nuclei initially in their ground state are discussed in 181Ta and 235U cases. A calculation of the nuclear excitation by electronic transition (NEET) rate is presented in a 201Hg plasma at local thermodynamic equilibrium. We also report on a new way of de-exciting isomeric states in plasma. This indirect decay mode is illustrated in the case of the 84Rb isomer nucleus. [Copyright &y& Elsevier]

Abstract: In rare decays experiments an effective online selection is a fundamental part of the data acquisition system (DAQ) in order to reduce both the quantity of data written on tape and the bandwidth requirements for the DAQ system. A multilevel architecture is commonly used to achieve a higher reduction factor, exploiting dedicated custom hardware and flexible software in standard computers. In this paper we discuss the possibility to use commercial video card processors (GPU) to build a fast and effective trigger system, both at hardware and software level. The computing power of the GPUs allows to design a real-time system in which trigger decisions are taken directly in the video processor with a defined maximum latency. This allows building lowest trigger levels based on standard off-the-shelf PCs with CPU and GPU (instead of the commonly adopted solutions based on custom electronics with FPGA or ASICs) with enhanced and high performance computation capabilities, resulting in high rejection power, high efficiency and simpler low level triggers. The ongoing work presented here shows the results achieved in the case of fast pattern matching in the RICH detector of the NA62 at CERN, aiming at measuring the Branching Ratio of the ultra rare decay , is considered as use case, although the versatility and the customizability of this approach easily allow exporting the concept to different contexts. In particular the application is related to particle identification in the RICH detector of the NA62 experiment, where the rate of events to be analyzed will be around 10MHz. The results obtained in lab tests are very encouraging to go towards a working prototype. Due to the use of off-the-shelf technology, in continuous development for other purposes (Video Games, image editing,…), the architecture described would be easily exported into other experiments, for building powerful, flexible and fully customizable trigger systems. [Copyright &y& Elsevier]

Abstract: The LHCb experiment will search for new physics in CP violation and rare decays from heavy flavour production at the LHC. Particle identification is provided by two Ring Imaging Cherenkov (RICH) detectors, which incorporate a total of 484 Hybrid Photon Detectors (HPDs). The RICH detectors are located in the fringe field of the LHCb dipole magnet and fields as large as 2.5mT have been measured in some regions occupied by the RICH 1 photodetectors. It is necessary to make corrections for the distortion of the ring-images measured by the HPDs. RICH 1 incorporates a magnetic calibration system comprising a series of collimated LEDs mounted on x–y stages which scan over the front-faces of the HPD arrays. A similar system based on commercial projectors is used on RICH 2. The calibration is performed in dedicated runs with dipole field on and off. The calibration parameters are then stored in the Conditions Database and applied to the LHC collision data reconstruction. This report will present the improvement in Cherenkov angular resolutions with the magnetic calibration. [Copyright &y& Elsevier]

Abstract: The alpha induced scintillation of the wavelength shifter 1,1,4,4-tetraphenyl-1,3-butadiene (TPB) was studied to improve the understanding of possible surface alpha backgrounds in the DEAP dark matter search experiment. We found that vacuum deposited thin TPB films emit photons per MeV under alpha particle excitation. The scintillation pulse shape consists of a double exponential decay with lifetimes of and . [Copyright &y& Elsevier]

Abstract: The WITCH experiment is a medium-scale experimental set-up located at ISOLDE/CERN. It combines a double Penning trap system with a retardation spectrometer for energy measurements of recoil ions from decay. For a correct operation of such a set-up a whole range of different devices is required. Along with the installation and optimization of the set-up a computer control system was developed to control these devices. The CS-Framework that is developed and maintained at GSI, was chosen as a basis for this control system as it is perfectly suited to handle the distributed nature of a control system.We report here on the required hardware for WITCH, along with the basis of this CS-Framework and the add-ons that were implemented for WITCH. [ABSTRACT FROM AUTHOR]

Abstract: We present a new Micro Pattern Gaseous Detector (MPGD) fabricated with nonpolymeric materials. The device structure is similar to a Microbulk Micromegas design, consisting of a punctured metal grid supported by a continuous perforated insulating structure. In this detector, the supporting structure is made out of silicon oxide. Devices were tested in He/iC4H10 (80/20) and Ar/iC4H10 (80/20) gas mixtures under 55Fe irradiation. Gas gain of 20,000 and energy resolution below 13% FWHM were achieved. The CMOS compatibility of the fabrication process has been studied in Timepix chips as well as individual 0.13-μm technology CMOS transistors. Complete detectors have been fabricated on top of Timepix chips. In an Ar/iC4H10 (80/20) gas mixture 55Fe decay events were recorded operating the Timepix chip in 2D readout mode. [ABSTRACT FROM AUTHOR]

Abstract: In rare decays experiments an effective trigger is crucial to reduce both the quantity of data written on tape and the bandwidth requirements for the DAQ (Data Acquisition) system. A multilevel architecture is commonly used to achieve a higher reduction factor, exploiting dedicated custom hardware and flexible software in standard computers. In this paper we discuss the possibility to use commercial video card processors (GPU) to build a fast and effective trigger system, both at hardware and software level. The case of fast pattern matching in the RICH detector of the NA62 experiment at CERN aiming at measuring the Branching Ratio of the ultra rare decay is considered as use case although the versatility and the customizability of this approach easily allow exporting the concept to different contexts. [ABSTRACT FROM AUTHOR]

Abstract: A 900-l liquid xenon (LXe) detector was constructed for the MEG experiment to look for . With proper calibration and monitoring the detector was successfully operated during the first physics data taking for three months in 2008. We evaluated the performance of the LXe detector around the energy of 52.8MeV by using 54.9-MeV photons obtained from decays. [ABSTRACT FROM AUTHOR]

Abstract: The goal of the NA62 experiment is to collect about 80 events with a S/B ratio of . The branching ratio (BR) for this decay is and can be predicted in the Standard Model with minimal theoretical uncertainties, making it a sensitive probe for new physics. Measurement of this BR is challenging because of the background from dominant channels. To reduce background from decays (BR=21%) to an acceptable level, the must be detected with an inefficiency of less than 10−8. NA62 will make use of the existing NA48 beam-line and liquid-krypton calorimeter. A new photon veto system consisting of 12 rings placed along the vacuum volume is needed to detect large-angle photons (7–50mrad) with an inefficiency below 10−4 over the energy interval from a few hundred MeV to 35GeV. A comprehensive R&D program was carried out in 2007–2008 to compare different detector technologies, including the re-use of lead-glass blocks from the OPAL barrel calorimeter, ultimately demonstrating the feasibility of this approach. In 2009, a complete prototype of one veto ring was constructed, complete with front-end electronics to measure energies through time-over-threshold with a dynamic range of 1000, and an in situ calibration and monitoring system. The prototype was successfully tested with electron and muon beams at the CERN SPS in fall 2009. The status of the project and present preliminary results from the recent tests will be reviewed. [ABSTRACT FROM AUTHOR]

Abstract: The NA62 experiment at CERN aims to measure the ultra-rare decay with a 10% accuracy; the main background, , is suppressed using kinematical cuts and exploiting the different stopping power of and . A further 0.5% suppression will be provided by a RICH detector, in a momentum range between 15 and 35GeV/c. In this paper the design parameters of a RICH detector that fulfills the NA62 experiment requirements will be described, as well as results from two different beam tests. [ABSTRACT FROM AUTHOR]

Abstract: 109Cd decays to the excited states of 109Ag through the electron capture decay mode. The evaluation of the complete decay scheme and data of 109Cd including the recent new measurements is presented in this report. The limitation of relative statistical weight method (LRSW) was applied to average numbers throughout the evaluation. The uncertainty assigned to the average value was always greater than or equal to the smallest uncertainty of the values used to calculate the average. The half-life is determined to be 462.0±0.3 days. All known measured absolute emission probabilities for gamma-ray and KX-ray have been examined. And the gamma-ray emission probability of the reference γ line of 88.0336keV is recommended to be 3.65±0.3%. The internal conversion coefficients and their uncertainties were used to obtain the complete decay intensity balance. The other decay characteristics are calculated using the ENSDF analysis program. Finally the 109Cd decay scheme was given. [ABSTRACT FROM AUTHOR]

Abstract: Terradex project aims to realise an accurate and programmable multiparametric tool which will measure relevant physical quantities such as observation time, energy and type of all decay products of three naturally occurring decay chains of uranium and thorium series present in nature as well as the decay products of man-made radioactivity. The measurements described in this work are based on the performance tests of the first version of an instrument that is designed to provide high counting accuracy, by introducing self-triggering, delayed time-coincidence technique, of products of a given decay chain. In order to qualify the technique and to calibrate the Terradex, a 222Rn source is used. The continuous and accurate monitoring of radon concentration in air is realised by observing the alpha and beta particles produced by the decay of 222Rn and its daughters and tag each of them with a precise occurrence time. The validity of delayed coincident technique by using the state of the art electronics with application of novel data sampling and analysis methods are discussed. The flexibility of sampling protocols and the advantages of online calibration capability to achieve the highest level of precision in natural and man-made radiation measurements are also described. [Copyright &y& Elsevier]

Abstract: The method of analysis of total absorption -ray spectra obtained in -decay measurements is studied. The analysis problem is reduced to the solution of a linear inverse problem. The performance and systematic uncertainties of different inverse algorithms are studied. The maximum entropy and the expectation-maximisation algorithms are found to be superior to the linear regularisation method. [Copyright &y& Elsevier]

Abstract: The method of analysis of -decay total absorption spectra in order to obtain -strength distributions is studied. The influence on the final result of unknown branching ratios in the electromagnetic de-excitation of levels in the daughter nucleus is investigated with the help of the statistical model of the population and decay of the nucleus. The total decay strength appears to be rather insensitive to assumptions on the branching ratios and the systematic uncertainty on the shape of the strength distribution is quantified. [Copyright &y& Elsevier]

The effect of undetected imperfections of the energy scale on the results of electron spectroscopy experiment is studied for the conditions close to the tritium β-decay experiment KATRIN (KATRIN Collaboration, 2001, arxiv: hep-ex/0109033). A numerical model of the experiment is developed, verified, and used to deduce general trends of fitted parameters. The effects of energy bias and of wrong slope of the calibration line are studied in more detail. [Copyright &y& Elsevier]

The potentiality of the coincidence technique to search for ββ decay processes in 130Ba has been studied. A BaF2 crystal scintillator with a mass of 3615 g and two low background NaI(Tl) detectors have been used for this purpose. The performances of the BaF2 detector in the used set-up have preliminarily been investigated, in particular: (i) the α/β light ratio, (ii) the pulse shape discrimination capability between α and β particles, (iii) the main radioactive contaminations of the crystal. As a result, new limits (90% CL) on the lifetimes of the following double beta decay processes in 130Ba have been determined: τ2β+0ν(0+→0+)>1.1×1017 y, τ2β+0ν(0+→21+)>1.5×1017 y, τECβ+0ν(0+→0+)>2.0×1017 y, τECβ+0ν(0+→21+)>1.6×1017 y, τECβ+0ν(0+→22+)>2.0×1017 y and τECβ+0ν(0+→4+)>1.1×1017 y. The new experimental limits obtained for the 0ν(0+→0+) decay modes represent a significant improvement with respect to those previously available for this isotope, while those involving excited levels are set here for the first time. [Copyright &y& Elsevier]

Abstract: MEMPHYS is a proposed 0.5Mton scale Water Cherenkov experiment to be performed deep underground. Possible sites are under study in the European FP7 design study LAGUNA. It is dedicated to nucleon decay, neutrinos from supernovæ, solar and atmospheric neutrinos, as well as neutrinos from a future Super-Beam or β-Beam to measure the mixing angle θ 13, the CP violating phase δ and the mass hierarchy. A small-scale prototype, Memphyno, has been constructed with the purpose of serving as a test bench for new photodetection and data acquisition solutions, such as grouped readout system. [Copyright &y& Elsevier]

Abstract: LHCb is a dedicated experiment to study new physics in the decays of beauty and charm hadrons at the Large Hadron Collider (LHC) at CERN. The Vertex Locator (VELO) is the silicon detector surrounding the interaction point and will be located only 7mm from the LHC beam during normal operation. The beauty and charm hadrons are identified through their flight distance in the VELO, and hence the detector is critical for both the trigger and offline physics analyses. The VELO has been commissioned and successfully operated during the initial running period of the LHC. The detector has been time aligned to the LHC beam, and spatially aligned. Preliminary operational results show a signal to noise ratio of 20:1, a cluster finding efficiency of 99.6%, and a best single hit precision of . [ABSTRACT FROM AUTHOR]

Abstract: The nuclides 168–170Pt were produced by bombarding isotopically enriched 92,94Mo targets with 336, 348MeV 78Kr ions. Prompt rays were detected at the target position and provided a selection criterion for the 168–170Pt nuclei. This technique enables the problem of the background from higher-energy decays in the spectrum to be circumvented. The Pt nuclei were separated in flight using the gas-filled separator RITU and implanted into the GREAT spectrometer, which was used to study subsequent decays. The -decay branching ratios of 164–166Os were deduced from the fraction of selected 168–170Pt nuclei correlated with decays of 164–166Os. The resulting branching ratios agree with the literature values but can have improved precision. [Copyright &y& Elsevier]