163Ho as a target for cosmic antineutrinos

The electron capture decay of the isotope 163Ho has been proposed since a long time as a candidate for measuring the electron neutrino mass and recently the interest on this idea has been renewed. A direct observation of the cosmic antineutrino background could be made using a target made of this isotope. We discuss the requirements for an experiment aiming to obtain this result, comparing it with experiments using tritium as target

Fluence Beam Monitor for High-Intensity Particle Beams Based on a Multi-Gap Ionization Chamber and a Method for Ion Recombination Correction

This work presents the tests of a multi-gap detector (MGD), composed of three parallel-plate ionization chambers (ICs) with different gap widths, assembled to prove the capability of correcting for charge volume recombination which is expected to occur when high fluence rates are delivered. Such beam conditions occur with a compact accelerator for charged particle therapy developed to reduce the costs, to accomplish faster treatments and to exploit different beam delivery techniques and dose rates as needed, for example, for range modulation and FLASH irradiations, respectively. The MGD was tested with carbon ions at the Centro Nazionale di Adroterapia Oncologica (CNAO Pavia, Italy), and with protons in two different beam lines: at Bern University Hospital with continuous beams and at the Laboratori Nazionale del Sud (Catania, Italy) of the Italian National Center of Nuclear Physics (INFN) with pulsed beams. For each accelerator, we took measurements with different beam intensities (up to the maximum rate of ionization achievable) and changed the detector bias voltage (V) in order to study the charge collection efficiency. Charge recombination models were used to evaluate the expected collected charge and to measure the linearity of the rate of ionization with the beam fluence rate. A phenomenological approach was used to determine the collection efficiency (f1) of the chamber with thinnest gap from the relative efficiencies, f1/f2 and f1/f3, exploiting the condition that, for each measurement, the three chambers were exposed to the same rate of ionization. Results prove that two calibration curves can be determined and used to correct the online measurements for the charge losses in the ICs for recombination

Exercise performance, haemodynamics, and respiratory pattern do not identify heart failure patients who end exercise with dyspnoea from those with fatigue

AIMS: The two main symptoms referred by chronic heart failure (HF) patients as the causes of exercise termination during maximal cardiopulmonary exercise testing (CPET) are muscular fatigue and dyspnoea. So far, a physiological explanation why some HF patients end exercise because of dyspnoea and others because of fatigue is not available. We assessed whether patients referring dyspnoea or muscular fatigue may be distinguished by different ventilator or haemodynamic behaviours during exercise. METHODS AND RESULTS: We analysed exercise data of 170 consecutive HF patients with reduced left ventricular ejection fraction in stable clinical condition. All patients underwent maximal CPET and a second maximal CPET with measurement of cardiac output by inert gas rebreathing at peak exercise. Thirty-eight (age 65.0 \ub1 11.1 years) and 132 (65.1 \ub1 11.4 years) patients terminated CPET because of dyspnoea and fatigue, respectively. Haemodynamic and cardiorespiratory parameters were the same in fatigue and dyspnoea patients. VO2 was 10.4 \ub1 3.2 and 10.5 \ub1 3.3 mL/min/kg at the anaerobic threshold and 15.5 \ub1 4.8 and 15.4 \ub1 4.3 at peak, in fatigue and dyspnoea patients, respectively. In fatigue and dyspnoea patients, peak heart rate was 110 \ub1 22 and 114 \ub1 22 beats/min, and VE/VCO2 and VO2 /work relationship slopes were 31.2 \ub1 6.8 and 30.6 \ub1 8.2 and 10.6 \ub1 4.2 and 11.4 \ub1 5.5 L/min/W, respectively. Peak cardiac output was 6.68 \ub1 2.51 and 6.21 \ub1 2.55 L/min (P = NS for all). CONCLUSIONS: In chronic HF patients in stable clinical condition, fatigue and dyspnoea as reasons of exercise termination do not highlight different ventilatory or haemodynamic patterns during effort

Urban PM2.5 Atlas: Air Quality in European cities

Many European cities suffer from poor air quality and regularly exceed both the European standards prescribed by the Air Quality Directive and the guidelines recommended by the World Health Organization. This is particularly the case for fine particulate matter (PM10) for which both the daily and yearly average limit values are regularly exceeded in many cities and several regions in Europe. Similar conclusions hold for PM2.5 where few cities manage to keep concentrations below the levels recommended by the WHO. Actions have been proposed and taken at the international, national and urban scales to reduce air pollution. While they have undoubtedly resulted in an overall improvement of the air quality over the years, there are still problems which are localised in specific regions and many cities. A key issue is thus to determine at which scale to act in order to abate these remaining air pollution problems most effectively. Central to this for cities, is a quantitative assessment of the different origins of air pollution in the city (urban, regional, national and transboundary) to support the design of efficient and effective air quality plans, which are a legal obligation for countries and regions whenever exceedances occur. The “Screening for High Emission Reduction Potentials for Air quality” tool (SHERPA) has been developed by the Joint Research Centre to quantify the origins of air pollution in cities and regions. In this Atlas, both the spatial (urban, country…) and sectoral (transport, residential, agriculture…) contributions are quantified for 150 European urban areas in Europe, where many of the current exceedances to the air quality EU limit values and WHO guidelines are reported. There is a need to provide information to improve air quality policy governance, to support authorities in choosing the most efficient actions at the appropriate administrative level and scale. In particular, actions at the local level focusing on the urban scale and at national/international level needs to be carefully balanced. Key conclusions are: • For many cities, local actions at the city scale are an effective means of improving air quality in that city. The overall conclusion is that cities have a role to play by taking actions at their own scale. It is important to emphasise that the emissions in cities contribute significantly to country and EU overall PM concentrations, reinforcing the important role of cities in reducing the air pollution through a multilevel approach. • Impacts of abatement measures on air quality are city specific The impact of a given abatement measure on air quality differs from city to city, even for cities that are located in the same country. Actions taken at different scales or in different activity sectors therefore lead to impacts on air quality that are city-specific. The diversity of possible responses to abatement measures stresses the need to take into account these city-specific circumstances when designing air quality plans. Actions that are efficient in one city might not be efficient in others. • Sectoral measures addressing agriculture at country or EU scale would have a clear benefit on urban air quality. Although agricultural emissions are limited in the "city" as defined here, agriculture considerably impacts air quality in many EU cities. The extent of the impact of agriculture on air quality is indicative of the potential of EU- or country-wide measures addressing this sector. Moreover, other sectoral measures can have an important potential at the urban scale even though they are applied at EU or country scale. This is the case of road transport where the EURO norms are, in practice, most effective in the areas where traffic is most important, i.e. cities.JRC.C.5-Air and Climat

PM2.5 source allocation in European cities: A SHERPA modelling study

Many European cities suffer from poor air quality and still exceed the European standards prescribed by the Air Quality Directive, and the guidelines recommended by the World Health Organization (WHO). This is especially the case for PM2.5, focus of this work. While international, national and local level actions to reduce air pollution have undoubtedly resulted in an overall improvement of the air quality over the years, there are still problems, which are localised in specific regions and many cities. A key issue is to determine at which scale to act in order to abate these remaining air pollution problems most effectively. Central to this, for cities, is a quantitative assessment of the different origins of air pollution (urban, regional, national and transboundary) to support the design of efficient, effective air quality plans, which are a legal obligation for countries and regions whenever exceedances occur. The “Screening for High Emission Reduction Potentials for Air quality” tool (SHERPA) is used in this work to quantify the origins of air pollution in cities and regions, both from a spatial (urban, country…) and sectoral (transport, residential, agriculture…) perspectives. For PM2.5 we conclude that (1) for many cities, local actions at the city scale are an effective means of improving air quality in that city; (2) the target sectors and scales to abate air pollution are city specific, even for cities that are located in the same country. Consequently, it is important to take into account these city-specific circumstances when designing air quality plans and (3) for many cities, sectoral measures addressing agriculture at country or EU scale would have a clear benefit on urban air quality

Calibration method and performance of a time-of-flight detector to measure absolute beam energy in proton therapy

Background: The beam energy is one of the most significant parameters in particle therapy since it is directly correlated to the particles' penetration depth inside the patient. Nowadays, the range accuracy is guaranteed by offline routine quality control checks mainly performed with water phantoms, 2D detectors with PMMA wedges, or multi-layer ionization chambers. The latter feature low sensitivity, slow collection time, and response dependent on external parameters, which represent limiting factors for the quality controls of beams delivered with fast energy switching modalities, as foreseen in future treatments. In this context, a device based on solid-state detectors technology, able to perform a direct and absolute beam energy measurement, is proposed as a viable alternative for quality assurance measurements and beam commissioning, paving the way for online range monitoring and treatment verification. Purpose: This work follows the proof of concept of an energy monitoring system for clinical proton beams, based on Ultra Fast Silicon Detectors (featuring tenths of ps time resolution in 50 μm active thickness, and single particle detection capability) and time-of-flight techniques. An upgrade of such a system is presented here, together with the description of a dedicated self-calibration method, proving that this second prototype is able to assess the mean particles energy of a monoenergetic beam without any constraint on the beam temporal structure, neither any a priori knowledge of the beam energy for the calibration of the system. Methods: A new detector geometry, consisting of sensors segmented in strips, has been designed and implemented in order to enhance the statistics of coincident protons, thus improving the accuracy of the measured time differences. The prototype was tested on the cyclotron proton beam of the Trento Protontherapy Center (TPC). In addition, a dedicated self-calibration method, exploiting the measurement of monoenergetic beams crossing the two telescope sensors for different flight distances, was introduced to remove the systematic uncertainties independently from any external reference. Results: The novel calibration strategy was applied to the experimental data collected at TPC (Trento) and CNAO (Pavia). Deviations between measured and reference beam energies in the order of a few hundreds of keV with a maximum uncertainty of 0.5 MeV were found, in compliance with the clinically required water range accuracy of 1 mm. Conclusions: The presented version of the telescope system, minimally perturbative of the beam, relies on a few seconds of acquisition time to achieve the required clinical accuracy and therefore represents a feasible solution for beam commission, quality assurance checks, and online beam energy monitoring

Phonon-Mediated KIDs as Light Detectors for Rare-Event Search: The CALDER Project

Background suppression plays a crucial role in experiments searching for rare events, like neutrino-less double beta decay (0 $$\nu$$ DBD) and dark matter. Large mass bolometers that are among the most competitive devices in this field would largely benefit from the development of ultrasensitive light detectors, as the combined readout of the bolometric and light signals enables the particle identification. The CALDER collaboration is developing cryogenic light detectors that will match the requirements of next generation experiments: noise lower than 20 eV RMS, large active area (several cm $$^{2}$$ ), wide temperature range of operation, and ease in fabricating and operating a thousand of detectors. For this purpose, we are exploiting the excellent energy resolution and the natural multiplexed read-out provided by kinetic inductance detectors (KIDs). These devices can be operated in a phonon-mediated approach, in which KIDs are coupled to a large insulating substrate in order to increase the active surface from a few mm $$^{2}$$ to 25 cm $$^{2}$$ . Our current best prototype, based on aluminum LEKIDs, reached a baseline sensitivity of 80 eV with an overall efficiency of about 20 %

Discovery of the 151^{151}Eu α\alpha decay

We report on the first compelling observation of $\alpha$ decay of $^{151}$Eu to the ground state of $^{147}$Pm. The measurement was performed using a 6.15 g Li$_6$Eu(BO$_3$)$_3$ crystal operated as a scintillating bolometer. The Q-value and half-life measured are: Q = 1948.9$\pm 6.9(stat.) \pm 5.1(syst.)$ keV, and T$_{1/2}=\left( 4.62\pm0.95(stat.)\pm0.68(syst.)\right) \times 10^{18}$ y . The half-life prediction of nuclear theory using the Coulomb and proximity potential model are in good agreement with this experimental result