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Superconducting Transition Edge Sensors employed in X-ray astrophysics space missions were realized and fully characterized in the Low temperature detector laboratory at UniGe. Several samples of Ir and Ir/Au bilayer films were grown by pulsed laser deposition at different deposition rate, varying thickness and resulting variability in critical temperature (Tc) was observed. In particular, we noticed two classes of films having discrete critical temperature (Tc), one at about the critical temperature of the bulk Ir and one at around 1.6 times compared to the bulk. Structural characterization was made and interesting correlation between critical temperature (Tc) and deposition conditions were found. Detailed X-Ray Diffraction investigations suggest a possible explanation of this effect with a clear correlation between microstrain value, grain size, and critical temperatures of the films. The study has been carried out to optimize the specified conditions to grow the film under which it is possible to accurately predict the critical temperature (Tc) by analyzing the X-ray diffraction patterns of Ir/Au films. [ABSTRACT FROM AUTHOR]

We are developing the Cryogenic AntiCoincidence detector (CryoAC) of the ATHENA X-IFU spectrometer. It is a TES-based particle detector aimed to reduce the background of the instrument. Here, we present the result obtained with the last CryoAC single-pixel prototype. It is based on a 1 cm2 silicon absorber sensed by a single 2 mm × 1 mm Ir/Au TES, featuring an on-chip heater for calibration and diagnostic purposes. We have illuminated the sample with 55Fe (6 keV line) and 241Am (60 keV line) radioactive sources, thus studying the detector response and the heater calibration accuracy at low energy. Furthermore, we have operated the sample in combination with a past-generation CryoAC prototype. Here, by analyzing the coincident detections between the two detectors, we have been able to characterize the background spectrum of the laboratory environment and disentangle the primary (i.e. cosmic muons) and secondaries (mostly secondary photons and electrons) signatures in the spectral shape. [ABSTRACT FROM AUTHOR]

The assessment of the absolute ν mass scale is a crucial challenge in today's particle physics and cosmology. The only experimental method which can provide a model-independent measurement is the investigation of endpoint distortion in beta/electron capture spectra. 163 Ho is a good choice thanks to its low electron capture Q value (about 2.8 keV), the proximity of the end-point to resonance M1 and its half-life (4570 years). The HOLMES experiment will exploit a calorimetric measurement of 163 Ho decay spectrum deploying a large set of cryogenic micro-calorimeters containing implanted 163 Ho. In order to get the best experimental sensitivity, it is crucial to combine high activity with very small undetected pileup contribution. Therefore, the main tasks of the experiment consist of: the development of about 1000 fast (3 μ s time resolution) cryogenic micro-calorimeters characterized by extraordinary energy resolution (down to few eV); the embedding of 163 Ho source inside the calorimeters, avoiding to spoil detectors' thermodynamical properties (mainly heat capacity) and preventing pileup issues. Moreover, it is also necessary to avoid contamination from other radionuclides, mainly 166 m Ho. Finally, an efficient high-bandwidth multiplexed readout has to be developed. The commissioning of the first implanted array is currently ongoing; the first data acquisition is expected to start in fall 2022. Here, the status of the experiment and the first results of detector commissioning will be discussed. [ABSTRACT FROM AUTHOR]

The HOLMES experiment aims to directly measure the ν mass studying the 163 Ho electron capture decay spectrum developing arrays of TES-based microcalorimeters implanted with O(300 Bq/detector) Ho atoms. The embedding of the source inside detectors is a crucial step of the experiment. Because the 163 Ho production process (neutron irradiation of a 162 Er sample) is not perfectly free from impurities, Ho source must be separated from a lot of contaminants. A chemical processing removes every species other than Ho, but it is not sufficient to remove all isotope-related background sources: Indeed, 166 m Ho beta decay can produce fake signal in the region of interest. For this reason, a dedicated implantation system was set up. It is designed to achieve the separation power better than 5 σ at 163/166 a.m.u. allowing an efficient Ho ions implantation inside microcalorimeter absorbers. Its main components are a 50 kV sputter-based ion source, a magnetic dipole and a target chamber. A specially designed co-evaporation system was designed to "grow" the gold microcalorimeter absorber during the implantation process, increasing the maximum achievable activity which can be implanted. The machine performances were evaluated by means of calibration runs using 63 Cu/ 65 Cu and Mo beams. A special care was given to the study of the more effective way to populate source plasma with Ho ions obtained from different Ho compounds by sputtering process. In this work, the machine development and commissioning are described. [ABSTRACT FROM AUTHOR]

The TORIO-229 experiment aims for a direct model-independent determination of the transition energy of 229 m Th produced in 233 U alpha decay. This knowledge will be of interest for the development of a scientific clock exploiting the thorium isomeric state, which would be able to significantly surpass the precision of the presently best clocks. As a detector for the isomeric transition, it is planned to use an array of fast transition-edge sensors (TESs) which demonstrated to be feasible in our previous work where the Ir/Au TES prototype demonstrated 4.6 ± 1.7 µs rise time, 5.8 ± 2.1 µs fall time and 0.789 ± 0.023 eV energy resolution and signal-to-noise ratio of ∼ 10 with one-photon (2.824 eV) signal, satisfying the experimental requirements. Such a microcalorimeter will allow to register the transition in every possible channel in the energy range from 3 to 50 eV and with a lifetime of > 5 µs. To have a full characterization of a single TES for the final detector array design, its thermal conductance has to be measured. In this contribution, we report on a test measurement of thermal coupling of a TORIO-229 prototype-like iridium-gold TES. [ABSTRACT FROM AUTHOR]

The X-IFU is the cryogenic spectrometer onboard the future ATHENA X-ray observatory. It is based on a large array of TES microcalorimeters, which work in combination with a Cryogenic AntiCoincidence detector (CryoAC). This is necessary to reduce the particle background level thus enabling part of the mission science goals. Here we present the first joint test of X-IFU TES array and CryoAC Demonstration Models, performed in a FDM setup. We show that it is possible to operate properly both detectors, and we provide a preliminary demonstration of the anti-coincidence capability of the system achieved by the simultaneous detection of cosmic muons. [ABSTRACT FROM AUTHOR]

We present a novel technique, called DSVP (Discrimination through Singular Vectors Projections), to discriminate spurious events within a dataset. The purpose of this paper is to lay down a general procedure which can be tailored for a broad variety of applications. After describing the general concept, we apply the algorithm to the problem of identifying nearly coincident events in low temperature microcalorimeters in order to push the time resolution close to its intrinsic limit. In fact, from simulated datasets it was possible to achieve an effective time resolution even shorter than the sampling time of the system considered. The obtained results are contextualized in the framework of the HOLMES experiment, which aims at directly measuring the neutrino mass with the calorimetric approach, allowing to significally improve its statistical sensitivity. [ABSTRACT FROM AUTHOR]

The absolute neutrino mass is still an unknown parameter in the modern landscape of particle physics. The HOLMES experiment aims at exploiting the calorimetric approach to directly measure the neutrino mass through the kinematic measurement of the decay products of the weak process decay of 163 Ho. This low energy decaying isotope, in fact, undergoes electron capture emitting a neutrino and leaving the daughter atom, 163 Dy ∗ , in an atomic excited state. This, in turn, relaxes by emitting electrons and, to a considerably lesser extent, photons. The high-energy portion of the calorimetric spectrum of this decay is affected by the non-vanishing neutrino mass value. Given the small fraction of events falling within the region of interest, to achieve a high experimental sensitivity on the neutrino mass, it is important to have a high activity combined with a very small undetected pileup contribution. To achieve these targets, the final configuration of HOLMES foresees the deployment of a large number of 163 Ho ion-implanted TESs characterized by an ambitiously high activity of 300 Hz each. In this paper, we outline the status of the major tasks that will bring HOLMES to achieve a statistical sensitivity on the neutrino mass as low as 2 eV/c 2 . [ABSTRACT FROM AUTHOR]

HOLMES is an experiment aiming at performing a direct measurement of the neutrino mass from the electron capture (EC) spectrum of 163 Ho . In order to reach a sensitivity of the order of ∼ 1 eV/c 2 on the neutrino mass, it is necessary to gather as many as 10 13 events in the 3-year projected live time of HOLMES, keeping the pileup fraction as low as 10 - 4 . This is not a trivial matter when it comes to low- temperature calorimeters, which usually have a rather slow time response. At the same time, a large number of detectors need to be operated simultaneously, and hence, in order to avoid an extremely large cryogenic facility, multiplexing is required. In this contribution, I will outline the current status and perspective of HOLMES, with special care devoted to the detectors and readout system, which have currently reached their target performance. [ABSTRACT FROM AUTHOR]

HOLMES is an experiment to directly measure the neutrino mass with a calorimetric approach. The calorimetric technique eliminates several systematic uncertainties usually present in spectrometers where the external source and decays to excited states affect the measurement. 163 Ho is chosen as source for its very low Q value (2.8 keV), the proximity of the end-point to resonance M1 and its half life (4570 year). These features are optimal to reach simultaneously a reasonable activity to have sufficient statistics in the end-point and a small quantity of 163 Ho embedded in the detector not to alter significantly its heat capacity. 163 Ho will be produced via neutron irradiation of enriched 162 Er 2 O 3 at the Institute Laue–Langevin (Grenoble, France), and chemically separated at Paul Scherrer Institut (Villigen, Switzerland). It will arrive at INFN laboratory of Genova in oxide form ( Ho 2 O 3 ) with traces of others Ho isotopes and contaminants not removable using chemical methods. In particular, the metastable 166 m Ho undergoes beta decay with a half life of about 1200 year, if present 166 m Ho induces background below 5 keV. The removal of these contaminants is critical for HOLMES so a dedicated system is being set up. The system is designed to achieve an optimal mass separation for 163 Ho and consists of two main components: an evaporation chamber and an ion implanter. In the evaporation chamber, holmium will be reduced in metallic form, using the reaction 2Y+Ho 2 O 3 → Y 2 O 3 +2Ho and used to produce a metallic target for the ion implanter source. The ion implanter consists of five main components: a Penning sputter ion source, an acceleration section, a magnetic/electrostatic mass analyser, a magnetic scanning stage and a focusing electrostatic triplet. In this contribution, we describe the procedures, under continuous refinement, for the holmium evaporation process, the ion-implanted metallic target production and the status of the ion implanter. [ABSTRACT FROM AUTHOR]

We present critical temperature measurements of titanium thin films annealed in an argon atmosphere at various temperatures. We are able to depress the TC by up to 200 mK from an initial TC of 540 mK by increasing the temperature at which the films are post-annealed from 80 to 275 ∘C. We find an anti-correlation trend between the annealing temperature and the measured TC. We also briefly discuss how we plan to use these films to produce TES detectors to be used in the LSPE/SWIPE balloon-borne cosmic microwave background polarimeter, which is slated to launch in December 2019. [ABSTRACT FROM AUTHOR]

The assessment of neutrino absolute mass scale is still a crucial challenge in today particle physics and cosmology. Beta or electron capture spectrum end-point study is currently the only experimental method which can provide a model-independent measurement of the absolute scale of neutrino mass. HOLMES is an experiment funded by the European Research Council to directly measure the neutrino mass. HOLMES will perform a calorimetric measurement of the energy released in the electron capture decay of the artificial isotope 163Ho. In a calorimetric measurement, the energy released in the decay process is entirely contained into the detector, except for the fraction taken away by the neutrino. This approach eliminates both the issues related to the use of an external source and the systematic uncertainties arising from decays on excited final states. The most suitable detectors for this type of measurement are low-temperature thermal detectors, where all the energy released into an absorber is converted into a temperature increase that can be measured by a sensitive thermometer directly coupled with the absorber. This measurement was originally proposed by De Rujula and Lusignoli (Nucl Phys B 219:277, 1983. 10.1016/0550-3213(83)90642-9), but only in the last decade the technological progress in detectors development has allowed to design a sensitive experiment. HOLMES plans to deploy a large array of low-temperature microcalorimeters with implanted 163Ho nuclei. In this contribution we outline the HOLMES project with its physics reach and technical challenges, along with its status and perspectives. [ABSTRACT FROM AUTHOR]

HOLMES is aiming at a direct measurement of neutrino mass by performing a calorimetric measurement of the energy released in the decay of 163Ho. In such approach, the 163Ho source, with the required activity, needs to be embedded in the detector. HOLMES will deploy a large array of transition-edge sensor microcalorimeters with implanted 163Ho ions. While good progress has been made in optimizing single pixel design and fabrication to achieve the target resolution, a major challenge is the fabrication of arrays of such microcalorimeters with the required amount of 163Ho ions embedded in the detectors absorber. We describe the multi-step microfabrication process implemented to produce the detector arrays for HOLMES. One crucial part of such process is the ability to perform co-deposition of gold during the 163Ho implantation process on the detectors absorber. We describe the UHV target chamber, with integrated gold deposition system, we have built to achieve this goal. [ABSTRACT FROM AUTHOR]

Measuring the neutrino mass is one of the most compelling issues in particle physics. HOLMES is an experiment for a direct measurement of the neutrino mass. HOLMES will perform a precise measurement of the end point of the electron capture decay spectrum of 163Ho in order to extract information on the neutrino mass with a sensitivity as low as 1 eV. HOLMES, in its final configuration, will deploy a 1000-pixel array of low-temperature microcalorimeters: each calorimeter is made of an absorber, where the Ho atoms will be implanted, coupled to a transition-edge sensor (TES) thermometer. The detectors will be operated at the working temperature of 100mK provided by a dilution refrigerator. In order to read out the 1000-detector array of HOLMES, a multiplexing system is necessary: the choice is to couple the transition-edge sensors to a multiplexed rf-SQUID. In this contribution we outline the progress made towards the final configuration of HOLMES regarding both the performances of the TES detectors and the characteristics of the multiplexing system. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the effect of external beam radiotherapy (EBRT) for head and neck cancer (HNC) the intimal-medial thickness (IMT) and the lumen of the carotid artery. Methods: Patients with HNC and an indication for EBRT were enrolled. A carotid artery color Doppler examination was performed before and 6 and 12 months after EBRT. Results: From 2008 to 2011, 50 patients were enrolled. The mean carotid IMT was 0.9 vs. 1.02 mm before and 6 months after EBRT, respectively ( p = 0.0001). The common carotid artery lumen was narrowed without statistical significance, 6 months after EBRT ( p = 0.3). 1 year from EBRT, the IMT increase and the lumen reduction were statistically significant ( p = 0.001, p = 0.01, respectively). Neurological events (stroke or TIA) were not observed. Conclusions: Our data showed a significant IMT increase 6 months from EBRT without a corresponding narrowing of the common carotid lumen while a significant increase 12 months after EBRT. [ABSTRACT FROM AUTHOR]

The Special Needs Clinic of the Johns Hopkins Bayview Medical Center in Baltimore, Maryland provides comprehensive treatment for patients with developmental or intellectual disability and psychiatric illness. This report describes the clinical characteristics and service utilization of patients attending this clinic. Factors that support quality mental health services that are both cost-effective and accessible are identified. [ABSTRACT FROM AUTHOR]

In order to evaluate interobserver and intraobserver agreement of the Frykman and AO classifications and their variations between assessors with different levels of experience, three hand specialists, a fellow and two senior residents classified radiographs of 200 fractures of the distal radius in anteroposterior and lateral views. Reproducibility was assessed by the use of the proportion of agreement and kappa coefficient between pairs of observers. The Frykman classification showed moderate interobserver reproducibility (kappa = 0.43) and good intraobserver reproducibility (kappa = 0.61). The experience of the reviewers did not significantly affect either of these. The AO system showed regular interobserver reproducibility (kappa = 0.37) and moderate intraobserver reproducibility (kappa = 0.57). The younger group obtained higher intraobserver agreement than the senior. Possible causes for the low reproducibility of both classifications are discussed together with a review of the literature. We do not recommend the Frykman or AO classifications for clinical application because of their questionable reproducibility. [ABSTRACT FROM AUTHOR]

We present the first performance results obtained with microwave multiplexed Transition Edge Sensors prototypes specifically designed for the HOLMES experiment, a project aimed at directly measuring the electron neutrino mass through the calorimetric measurement of the 163 Ho electron capture spectrum. The detectors required for such an experiment feature a high energy resolution at the Q–value of the transition, around ∼ 2.8 keV, and a fast response time combined with the compatibility to be multiplexed in large arrays in order to collect a large statistics while keeping the pile-up contribution as small as possible. In addition, the design has to be suitable for future ion-implantation of 163 Ho. The results obtained in these tests allowed us to identify the optimal detector design among several prototypes. The chosen detector achieved an energy resolution of (4.5 ± 0.3) eV on the chlorine K α line, at ∼ 2.6 keV, obtained with an exponential rise time of 14 μ s. The achievements described in this paper pose a milestone for the HOLMES detectors, setting a baseline for the subsequent developments, aiming to the actual ion-implantation of the 163 Ho nuclei. In the first section the HOLMES experiment is outlined along with its physics goal, while in the second section the HOLMES detectors are described; the experimental set-up and the calibration source used for the measurements described in this paper are reported in Sects. 3 and 4, respectively; finally, the details of the data analysis and the results obtained are reported in Sect. 6. [ABSTRACT FROM AUTHOR]

Presents a letter to the editor regarding Venous thromboembolism.