One step into Holmes project. Simulation of the deposition of a metallic Ho film on a target.

This work shows one of the activity of the group in the framework of the HOLMES project for direct neutrino mass search. Starting from Ho oxide and working at high temperature, it is possible to obtain the deposition of a metal Ho film which is necessary for the implantation into cryogenic detectors. A simulation has been developed to evaluate the distribution of the deposition of metallic Holmium onto a target used as a trap and to estimate the efficiency of the process and eventually optimize controllable parameters. Object of this work is the simulation itself, its design, implementations and a discussion of the results

Mesoporous Titanium Dioxide Thin Layers for Gas Sensor Applications: Vacuum Deposition and Electrochemical Anodization

Titanium dioxide (TiO2) thin films were prepared by means of Anodic Spark Deposition (ASD) from thin and flat metallic titanium (Ti) films pre-deposited on high quality quartz slides by electron beam evaporation. AFM analysis indicates the formation of uniform mesoporous layers and a definite increase (about 50%) of the film thickness upon anodisation. The oxide mesoporous films have been characterized by XPS and Raman spectroscopy. Raman spectra of mesoporous TiO2 films were characterized by well-defined peaks related to anatase structure. An incomplete phase transition from anatase to rutile was observed upon annealing at temperatures up to 900 \ub0C for 3h

Modification of lymphoscintigraphic sentinel node identification before and after excisional biopsy of primary cutaneous melanoma

The aim of this study was to determine whether excision biopsy and primary closure of primary cutaneous melanoma modifies lymphatic drainage and accuracy of sentinel node biopsy. Thirty patients with 31 cutaneous melanomas were prospectively enrolled to undergo lymphoscintigraphy (LS) before and after excision biopsy. 99mTc-human serum albumin nanocolloid was first injected intradermally around the primary tumor and subsequently, after excision biopsy, adjacent to the scar. Sentinel nodes were identified by preoperative LS and the γ-probe. Patent Blue V dye was injected intraoperatively before sentinel node biopsy. Intraoperative sentinel node identification was 100%. In 23 of 31 cases, both LSs were concordant in terms of nodal basins visualized. Two patients had a basin downstaged and six patients had a basin upstaged by the second LS. Only 50% of LS hot nodes stained blue (42 of 84). In 24 of 31 cases, the sentinel node was negative for metastases. Seven patients underwent complete lymph node dissection because of sentinel node positivity. Only one patient had metastases also to a non-sentinel node. After a median follow-up of 30 months lymph node metastases have not been observed in the eight discordant cases. This study shows that sentinel node identification and biopsy after lymphatic mapping is accurate after excision biopsy of primary cutaneous melanoma. Excision biopsy may, however, modify lymphatic drainage and a narrow excision margin should be performed if melanoma is suspected. © 2008 Wolters Kluwer Health Lippincott Williams & Wilkins

Modification of lymphoscintigraphic sentinel node identification before and after excisional biopsy of primary cutaneous melanoma

The aim of this study was to determine whether excision biopsy and primary closure of primary cutaneous melanoma modifies lymphatic drainage and accuracy of sentinel node biopsy. Thirty patients with 31 cutaneous melanomas were prospectively enrolled to undergo lymphoscintigraphy (LS) before and after excision biopsy. 99mTc-human serum albumin nanocolloid was first injected intradermally around the primary tumor and subsequently, after excision biopsy, adjacent to the scar. Sentinel nodes were identified by preoperative LS and the γ-probe. Patent Blue V dye was injected intraoperatively before sentinel node biopsy. Intraoperative sentinel node identification was 100%. In 23 of 31 cases, both LSs were concordant in terms of nodal basins visualized. Two patients had a basin downstaged and six patients had a basin upstaged by the second LS. Only 50% of LS hot nodes stained blue (42 of 84). In 24 of 31 cases, the sentinel node was negative for metastases. Seven patients underwent complete lymph node dissection because of sentinel node positivity. Only one patient had metastases also to a non-sentinel node. After a median follow-up of 30 months lymph node metastases have not been observed in the eight discordant cases. This study shows that sentinel node identification and biopsy after lymphatic mapping is accurate after excision biopsy of primary cutaneous melanoma. Excision biopsy may, however, modify lymphatic drainage and a narrow excision margin should be performed if melanoma is suspected. © 2008 Wolters Kluwer Health Lippincott Williams & Wilkins

Pixelated positron timing counter with SiPM-readout scintillator for MEG II experiment

In this paper, we introduce the positron timing counter (TC) for the MEG II experiment as an application of Silicon PhotoMultipliers (SiPM) to high-resolution timing measurement. MEG II will search for the μ → eγ decay and needs a precise measurement of the positron timing. The TC is segmented in 512 counters, composed of a scintillator plate readout by SiPMs, to obtain multiple hit positron timing simultaneously such to achieve an excellent overall timing resolution of ∼30 ps. We performed single counter R&D to optimize the choice of the SiPM manufacturer, the number of the SiPMs, and their connection. To obtain the best resolution, we decided to employ AdvanSiD SiPMs, six of which are attached at both ends connected in series. Moreover we carried out beam tests with 8-9 counters prototypes, where we proved that positron multiple hits improve the resolution according to expectation. The desgin phase of the TC is almost finished and is under construction

The Cryogenic AntiCoincidence detector for ATHENA: The progress towards the final pixel design

"The Hot and Energetic Universe" is the scientific theme approved by the ESA SPC for a Large mission to be flown in the next ESA slot (2028th) timeframe. ATHENA is a space mission proposal tailored on this scientific theme. It will be the first X-ray mission able to perform the so-called "Integral field spectroscopy", by coupling a high-resolution spectrometer, the X-ray Integral Field Unit (X-IFU), to a high performance optics so providing detailed images of its field of view (5' in diameter) with an angular resolution of 5" and fine energy-spectra (2.5eV@E<7keV). The X-IFU is a kilo-pixel array based on TES (Transition Edge Sensor) microcalorimeters providing high resolution spectroscopy in the 0.2-12 keV range. Some goals is the detection of faint and diffuse sources as Warm Hot Intergalactic Medium (WHIM) or galaxies outskirts. To reach its challenging scientific aims, it is necessary to shield efficiently the X-IFU instrument against background induced by external particles: the goal is 0.005 cts/cm2/s/keV. This scientific requirement can be met by using an active Cryogenic AntiCoincidence (CryoAC) detector placed very close to X-IFU (\ue2\u88\ubc 1 mm below). This is shown by our GEANT4 simulation of the expected background at L2 orbit. The CryoAC is a TES based detector as the X-IFU sharing with it thermal and mechanical interfaces, so increasing the Technology Readiness Level (TRL) of the payload. It is a 2x2 array of microcalorimeter detectors made by Silicon absorber (each of about 80 mm2 and 300 \uce\ubcm thick) and sensed by an Ir TES. This choice shows that it is possible to operate such a detector in the so-called athermal regime which gives a response faster than the X-IFU (< 30 \uce\ubcs), and low energy threshold (above few keV). Our consortium has developed and tested several samples, some of these also featured by the presence of Al-fins to efficiently collect the athermal phonons, and increased x-ray absorber area (up to 1 cm2). Here the results of deep test related to one of the last sample produced (namely AC-S5), and steps to reach the final detector design will be discussed

The Status of the MARE Experiment with 187Re and 163Ho Isotopes

Neutrino oscillation experiments have proved that neutrinos are massive particles but the assessment of their absolute mass scale is still an outstanding challenge in today particle physics and cosmology. The laboratory experiments dedicated to effective electron-neutrino mass determination are the ones based on the study of single beta decay or electron capture (EC) decay. Exploiting only on energy-momentum conservation, this kinematic measurement is the only one which permits to estimate neutrino masses without theoretical assumptions on neutrino nature and it is truly modelindependent. To date the most competitive isotopes for a calorimetric measurement of the neutrino mass are 187Re and 163Ho. While the first decays beta, the latter decays via electron capture, and both have a Q-value around 2.5 keV. The measurement of 163Ho EC is an appealing alternative to the 187Re beta decay measurement because few nuclei are needed and it is a self-calibrating measurement. In this context the MARE project, based on rhenium thermal detectors has been born. We report here the status of MARE in Milan with Rhenium and the activity concerning the production of radioactive 163Ho isotope in the framework of MARE

HOLMES: The electron capture decay of 163Ho to measure the electron neutrino mass with sub-eV sensitivity

The European Research Council has recently funded HOLMES, a new experiment to directly measure the neutrino mass. HOLMES will perform a calorimetric measurement of the energy released in the decay of 163Ho. The calorimetric measurement eliminates systematic uncertainties arising from the use of external beta sources, as in experiments with beta spectrometers. This measurement was proposed in 1982 by A. De Rujula and M. Lusignoli, but only recently the detector technological progress allowed to design a sensitive experiment. HOLMES will deploy a large array of low temperature microcalorimeters with implanted 163Ho nuclei. The resulting mass sensitivity will be as low as 0.4 eV. HOLMES will be an important step forward in the direct neutrino mass measurement with a calorimetric approach as an alternative to spectrometry. It will also establish the potential of this approach to extend the sensitivity down to 0.1 eV. We outline here the project with its technical challenges and perspectives.Comment: 11 pages, 9 figure

Villard:20 IN FRAGILIA. Reconstructing through the waters of Ischia

Il seminario Villard:20 ha inteso proseguire la riflessione sulla ricostruzione intesa non soltanto come nuova edificazione o risanamento di un territorio colpito da eventi sismici, ma anche come reinterpretazione di territori fragili, le cui criticità sono acuite da rapidi processi di antropizzazione che sovente mettono in crisi l’identità dei luoghi. Il terremoto dell’estate 2017 ha riportato sotto i riflettori Ischia nella sua consistenza di vulcano attivo, evidenziandone l’elevato grado rischio. Un’ansia di ricostruzione pervade l’isola che, appiattita dai media in un’immagine di pericolo ed abusivismo, vede minacciata la sua principale economia: il turismo. Villard:20 assume le acque di Ischia come risorsa e chiave di lettura principale per la ricostruzione: la diffusione, la varietà e le proprietà terapeutiche delle acque ischitane costituiscono il corollario della essenza vulcanica che più ha inciso nel determinare la vocazione turistica dell’isola, differenziando e specificando la sua offerta rispetto alle vicine isole del golfo partenopeo. Le aree di progetto, individuate nel Comune di Ischia recano in sé temi progettuali specifici che nell’insieme hanno l’obiettivo di aprire l’isola ad un turismo sostenibile, responsabile, aderente alle specificità di un’isola dove le acque tornino ad ispirare declinazioni di spazi intimi o grandiosi, pubblici o privat