Bismuth germanate (BGO) is a well known high density scintillating material widely used in many applications such as high energy physics and medical imaging. Bismuth silicate (BSO) features ...properties similar to BGO in terms of stopping power and Cherenkov photon yield with a lower scintillation light output but faster decay time, thus being more attractive for applications in high-rate environments. Mixed crystals such as Bi4(GexSi1−x)3O12 (BGSO, with x varying from 0 to 1) make it possible to optimize decay time and light yield based on the detector needs.
A characterization campaign of the optical and scintillation properties of two sets of BGSO mixed crystals with Ge fraction varying from 0 to 100% was performed. A coincidence time resolution (CTR) at 511 keV of 208 ±2 ps FWHM was measured for a 2 × 2 × 3 mm3 pixel with 40% Ge, while the optimum value obtained for the effective decay time is 49.9 ±1.8 ns for a 6 × 6 × 0.7 mm3 plate-shaped sample with 30% Ge. Furthermore the smallest slow decay time component achieved is 101 ±2 ns and is obtained for the plate-shaped sample with 30% Ge, while the largest is 236 ±5 ns for a pure BGO sample with the same geometry.
In addition we demonstrated the possibility to efficiently separate the Cherenkov and scintillation light produced in a pure BSO sample. Such a technique could be exploited in a crystal-based dual-readout calorimeter to improve the energy resolution for hadronic showers and jets.
A spaghetti calorimeter (SPACAL) prototype with scintillating crystal fibres was assembled and tested with electron beams of energy from 1 to 5 GeV. The prototype comprised radiation-hard ...Cerium-doped Gd3Al2Ga3O12 (GAGG:Ce) and Y3Al5O12 (YAG:Ce) embedded in a pure tungsten absorber. The energy resolution was studied as a function of the incidence angle of the beam and found to be of the order of 10%/E⊕1%, in line with the LHCb Shashlik technology. The time resolution was measured with metal channel dynode photomultipliers placed in contact with the fibres or coupled via a light guide, additionally testing an optical tape to glue the components. Time resolution of a few tens of picosecond was achieved for all the energies reaching down to (18.5 ± 0.2) ps at 5 GeV.
A novel crystal scintillator of RbBa2I5:Eu2+ was grown by the Bridgman–Stockbarger method. Its luminescence and scintillation properties were investigated. Under X-ray excitation, the crystal ...demonstrates blue luminescence peaking at 436 nm associated with 4f65d1→ 4f7 radiative transitions of Eu2+ ions. The main X-ray luminescence decay constant is 800 ns. The light output of RbBa2I5:3%Eu2+ sample under 662 keV excitation is 58,200 ph/MeV.
•RbBa2I5:3%Eu2+ crystal was grown using the Bridgman–Stockbarger technique.•Its luminescence and scintillation properties have been investigated.•Under 662 keV excitation, RbBa2I5:3%Eu2+ showed a light output of 58,200 ph/MeV.
Particle physics experiments running at future accelerator facilities will rely on fast timing detectors to cope with high event pileup and to enhance particle identification capabilities. Direct ...band gap engineered semiconductor nanostructures show a high potential for emission of prompt photons due to quantum confinement, standing out in fast timing and high light yield with potential low cost production, thus triggering interest in the high energy physics community. In this contribution, characterization results of the scintillation properties of some promising nanomaterial scintillators will be presented and an overview of possible light-based detector designs based on these nanomaterials will be given, focusing on the NanoCal Blue Sky project of the European project AIDAinnova, a new generation of shashlik calorimeters. First results, obtained during test beam activities, will be presented as well.
A series of Cs0.2Rb0.8Ca1–xEuxBr3 (0 ≤ x ≤ 0.08) crystals doped with different concentrations of Eu2+ were grown using the Bridgman-Stockbarger method. The work describes the influence of Eu2+ ...concentration on the luminescent and kinetic properties of Cs0.2Rb0.8Ca1–xEuxBr3 crystals, as well as on their scintillation performance. The maximum in the radioluminescence spectra of these crystals shifts from 439 to 446 nm with increasing europium concentration. The scintillation decay times of Cs0.2Rb0.8Ca1–xEuxBr3 lengthen with the Eu2+ content. The best light output of 33600 photons/MeV is obtained for Cs0.2Rb0.8Ca0.93Eu0.07Br3, and the best energy resolution of 6.9% is found for Cs0.2Rb0.8Ca0.94Eu0.06Br3.
New Cs0.2Rb0.8Ca1−xEuxBr3 scintillation crystals were grown by the Bridgman-Stockbarger technique. The effect of the Eu2+ concentration on their luminescent and scintillation properties was studied. It is found that the optimal concentration of europium for Cs0.2Rb0.8Ca1−xEuxBr3 crystals is 0.06–0.07. Display omitted
•The Cs0.2Rb0.8Ca1−xEuxBr3 series was grown with various activator concentrations.•The scintillation properties of Cs0.2Rb0.8Ca1−xEuxBr3 crystals were studied.•The highest scintillation yield is obtained for Cs0.2Rb0.8Ca0.93Eu0.07Br3 crystal.
This prospective cohort study aimed at evaluating patterns of polypharmacy and aggressive and violent behavior during a 1-year follow-up in patients with severe mental disorders.
A total of 340 ...patients (125 inpatients from residential facilities and 215 outpatients) were evaluated at baseline with the Structured Clinical Interview for DSM-IV Axis I and II, Brief Psychiatric Rating Scale, Specific Levels of Functioning scale, Brown-Goodwin Lifetime History of Aggression, Buss-Durkee Hostility Inventory, Barratt Impulsiveness Scale, and State-Trait Anger Expression Inventory-2. Aggressive behavior was rated every 15 days with the Modified Overt Aggression Scale and treatment compliance with the Medication Adherence Rating Scale.
The whole sample was prescribed mainly antipsychotics with high levels of polypharmacy. Clozapine prescription and higher compliance were associated with lower levels of aggressive and violent behavior. Patients with a history of violence who took clozapine were prescribed the highest number of drugs. The patterns of cumulative Modified Overt Aggression Scale mean scores of patients taking clozapine (n = 46), other antipsychotics (n = 257), and no antipsychotics (n = 37) were significantly different (P = .001). Patients taking clozapine showed a time trend at 1-year follow-up (24 evaluations) indicating a significantly lower level of aggressive behavior. Patient higher compliance was also associated with lower Modified Overt Aggression Scale ratings during the 1-year follow-up.
Both inpatients and outpatients showed high levels of polypharmacy. Clozapine prescription was associated with lower Modified Overt Aggression Scale ratings compared with any other antipsychotics or other psychotropic drugs. Higher compliance was associated with lower levels of aggressive and violent behavior.
Adenomatoid tumor represents a type of mesothelioma apparently confined to the genital tract and characterized by its benign behavior. Its morphological aspects are well known and, until now, it has ...been described as a nodular mass except for a case diffusely infiltrating the entire myometrium in an immunosuppressed patient. We report a case of benign mesothelial tumor characterized by histological, immunophenotypical and ultrastructural features of an otherwise typical adenomatoid tumor but diffusely growing below uterine serosal surface into the myometrium without discernible borders. The existence of a diffuse type of adenomatoid tumor might reflect a different nature of this neoplasm leading to the hypothesis that this variant of benign mesothelioma represents a distinct biological entity.
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