Native NIR-emitting single colour centres in CVD diamond

Single-photon sources are a fundamental element for developing quantum technologies, and sources based on colour centres in diamonds are among the most promising candidates. The well-known NV centres are characterized by several limitations, thus few other defects have recently been considered. In the present work, we characterize in detail native efficient single colour centres emitting in the near infra-red in both standard IIa single-crystal and electronic-grade polycrystalline commercial CVD diamond samples. In the former case, a high-temperature annealing process in vacuum is necessary to induce the formation/activation of luminescent centres with good emission properties, while in the latter case the annealing process has marginal beneficial effects on the number and performances of native centres in commercially available samples. Although displaying significant variability in several photo physical properties (emission wavelength, emission rate instabilities, saturation behaviours), these centres generally display appealing photophysical properties for applications as single photon sources: short lifetimes, high emission rates and strongly polarized light. The native centres are tentatively attributed to impurities incorporated in the diamond crystal during the CVD growth of high-quality type IIa samples, and offer promising perspectives in diamond-based photonics.Comment: 27 pages, 10 figures. Submitted to "New Journal of Phsyics", NJP-100003.R

Energy and angular momentum sharing in dissipative collisions

Primary and secondary masses of heavy reaction products have been deduced from kinematics and E-ToF measurements, respectively, for the direct and reverse collisions of 93Nb and 116Sn at 25 AMeV. Light charged particles have also been measured in coincidence with the heavy fragments. Direct experimental evidence of the correlation of energy-sharing with net mass transfer has been found using the information from both the heavy fragments and the light charged particles. The ratio of Hydrogen and Helium multiplicities points to a further correlation of angular momentum sharing with net mass transfer.Comment: 21 pages, 20 figures. Submitted to European Physics Journal

Spatial Resolution of Double-Sided Silicon Microstrip Detectors for the PAMELA Apparatus

The PAMELA apparatus has been assembled and it is ready to be launched in a satellite mission to study mainly the antiparticle component of cosmic rays. In this paper the performances obtained for the silicon microstrip detectors used in the magnetic spectrometer are presented. This subdetector reconstructs the curvature of a charged particle in the magnetic field produced by a permanent magnet and consequently determines momentum and charge sign, thanks to a very good accuracy in the position measurements (better than 3 um in the bending coordinate). A complete simulation of the silicon microstrip detectors has been developed in order to investigate in great detail the sensor's characteristics. Simulated events have been then compared with data gathered from minimum ionizing particle (MIP) beams during the last years in order to tune free parameters of the simulation. Finally some either widely used or original position finding algorithms, designed for such kind of detectors, have been applied to events with different incidence angles. As a result of the analysis, a method of impact point reconstruction can be chosen, depending on both the particle's incidence angle and the cluster multiplicity, so as to maximize the capability of the spectrometer in antiparticle tagging.Comment: 28 pages, 18 figures, submitted to Nuclear Instruments and Methods in Physics Research

Particle and light fragment emission in peripheral heavy ion collisions at Fermi energies

A systematic investigation of the average multiplicities of light charged particles and intermediate mass fragments emitted in peripheral and semiperipheral collisions is presented as a function of the beam energy, violence of the collision and mass of the system. The data have been collected with the "Fiasco" setup in the reactions 93Nb+93Nb at 17, 23, 30, 38AMeV and 116Sn+116Sn at 30, 38AMeV. The midvelocity emission has been separated from the emission of the projectile-like fragment. This last component appears to be compatible with an evaporation from an equilibrated source at normal density, as described by the statistical code Gemini at the appropriate excitation energy. On the contrary, the midvelocity emission presents remarkable differences for what concerns both the dependence of the multiplicities on the energy deposited in the midvelocity region and the isotopic composition of the emitted light charged particles.Comment: 18 pages, 17 figures, Revtex

Ex vivo model predicted in vivo efficacy of CFTR modulator therapy in a child with rare genotype

Background: New drugs that target the basic defect in cystic fibrosis (CF) patients may now be used in a large number of patients carrying responsive mutations. Nevertheless, further research is needed to extend the benefit of these treatments to patients with rare mutations that are still uncharacterized in vitro and that are not included in clinical trials. For this purpose, ex vivo models are necessary to preliminary assessing the effect of CFTR modulators in these cases. Method: We report the clinical effectiveness of lumacaftor/ivacaftor therapy prescribed to a CF child with a rare genetic profile (p.Phe508del/p.Gly970Asp) after testing the drug on nasal epithelial cells. We observed a significant drop of the sweat chloride value, as of the lung clearance index. A longer follow-up period is needed to define the effects of therapy on pancreatic status, although an increase of the fecal elastase values was found. Conclusion: Drug response obtained on nasal epithelial cells correlates with changes in vivo therapeutic endpoints and can be a predictor of clinical efficacy of novel drugs especially in pediatric patients

Space and Time pattern of mid-velocity IMF emission in peripheral heavy-ion collisions at Fermi energies

The emission pattern in the V_perp - V_par plane of Intermediate Mass Fragments with Z=3-7 (IMF) has been studied in the collision 116Sn + 93Nb at 29.5 AMeV as a function of the Total Kinetic Energy Loss of the reaction. This pattern shows that for peripheral reactions most of IMF's are emitted at mid-velocity. Coulomb trajectory calculations demonstrate that these IMF's are produced in the early stages of the reaction and shed light on geometrical details of these emissions, suggesting that the IMF's originate both from the neck and the surface of the interacting nuclei.Comment: 4 pages, 3 figures, RevTex 3.1, submitted to Phys. Rev. Letter

VALIDAZIONE DEI DATI DELL’OSSERVATORIO GEOMAGNETICO DI DURONIA

La validazione dei dati illustrata in questa nota concerne due bande di frequenza distinte, separate dalla frequenza di ripetizione delle misure assolute ƒm. Questa frequenza definisce due regioni spettrali: ƒ > ƒm e ƒ < ƒm. Nella prima regione spettrale il rumore complessivo non viene discriminato dalle misure assolute perché si colloca al di fuori della banda delle misure assolute stesse, nella seconda regione spettrale le misure assolute consentono di eliminare, entro certi limiti, le varie derive introdotte dalla catena strumentale. Un terzo segmento spettrale, di grande interesse dal punto di vista del rumore, si colloca nella banda delle pulsazioni magnetosferiche (0.001 Hz – 1 Hz). In questa banda giace il ginocchio che separa il rumore bianco da quello colorato. In questa nota si pongono in evidenza soprattutto le componenti del rumore che non vengono discriminate dalle misure assolute

Un anno di Comitato Unico di Garanzia: riflessioni all'INGV

L’Istituto Nazionale di Geofisica e Vulcanologia - INGV ha istituito il Comitato Unico di Garanzia per le pari opportunità, la valorizzazione del benessere di chi lavora e contro le discriminazioni – CUG nel luglio 2011, ai sensi della L.183/2010. Il CUG ha assunto, estendendoli, i compiti del precedente Comitato Pari Opportunità, ossia, come da delibera CD n.4.3.2.11 del 28/6/2011: • focalizzare i problemi relativi alle pari opportunità; • contribuire a migliorare la qualità della vita negli ambienti di lavoro e a valorizzare le risorse umane; • verificare gli equilibri tra i sessi nelle posizioni funzionali a parità di requisiti professionali; • formulare proposte per: la gestione flessibile delle risorse umane e le attività di formazione professionale; è inoltre chiamato a perseguire gli obiettivi della direttiva dei dipartimenti della Funzione Pubblica e per le Pari Opportunità del 4 marzo 2011, per esercitare compiti propositivi, consultivi e di verifica. I compiti affidati dall’Amministrazione da un lato e le sollecitazioni ricevute dal personale dall’altro hanno portato ad una serie di azioni, tra le principali: • la redazione di un Codice per la tutela della dignità delle persone e per la prevenzione delle molestie sessuali e morali dell’INGV, l’individuazione della Consigliera di Fiducia e l’avvio di un ciclo di seminari sull’argomento, nell’ambito della prevenzione delle discriminazioni; • una lettura di genere delle bozze dei nuovi regolamenti dell’ente, con proposte di modifiche ispirate alla Carta Europea dei Ricercatori – CdR (e.g. principi di Non discriminazione, Equilibrio di genere) e alla normativa in tema di pari opportunità e tutela della maternità, parte delle quali recepite nel Regolamento del Personale e nel Disciplinare in materia di orario di servizio; un’azione, questa, legata all’adesione in via sperimentale alla Human Resources Strategy for Researchers, iniziativa della Comunità Europea per l’effettiva implementazione della CdR; • nell’ambito del processo di valutazione della ricerca dell’ANVUR, l’evidenziazione di alcune criticità presenti nel bando, in relazione alla valutazione della maternità, risultate in una interrogazione parlamentare e in una lettera aperta, grazie al contributo dell’Associazione Donne e Scienza e dei CUG dell’INFN e del CNR. Le esperienze fatte confermano l’opportunità di dare voce a tutte le donne dell’Istituto e di fare rete tra i Comitati degli enti di ricerca.UnpublishedCertosa di Pontignano (Siena), Italyope

Micro-beam and pulsed laser beam techniques for the micro-fabrication of diamond surface and bulk structures

Micro-fabrication in diamond is involved in a wide set of emerging technologies, exploiting the exceptional characteristics of diamond for application in bio-physics, photonics, radiation detection. Micro ion-beam irradiation and pulsed laser irradiation are complementary techniques, which permit the implementation of complex geometries, by modification and functionalization of surface and/or bulk material, modifying the optical, electrical and mechanical characteristics of the material. In this article we summarize the work done in Florence (Italy) concerning ion beam and pulsed laser beam micro-fabrication in diamond.Comment: 14 pages, 5 figure