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Small extracellular vesicles impact on target membrane structure and dynamics
No full textExtracellular vesicles (EVs) are a main intercellular communication system. To deepen their cell internalization mechanisms, we applied scanning calorimetry to EVs mixed with model membranes of variable complex composition. Our results contribute to the description of EVs mixing mechanisms showing their impact on lipid ordering and target membrane structuring
Activity measurement of a 64Cu sample activated by a 14 MeV neutron beam
No full textA new activity measurement system based on two NaI(Tl) 5 × 5 cylindrical crystals, placed at 180◦, was built at the ENEA Italian National Institute of Ionizing Radiation Metrology (INMRI) and characterized by Monte Carlo
simulations in FLUKA code. It was used to determine the activity of a 64Cu source, produced at ENEA’s Frascati Neutron Generator (FNG) by irradiating an enriched 64Zn sample with a 14 MeV neutron beam. Radiochemical treatments of the activated sample were performed at the ENEA Nuclear Material characterization Laboratory and Nuclear Waste Management (NMLNWM) to separate 64Cu from the zinc target and other impurities. The radioactive solution resulting from the process was measured using the Triple-to-Double Coincidence Ratio (TDCR) technique. The comparison of 64Cu activity in the solid sample and in the radioactive solution allowed to assess the separation efficiency. This study opened interesting perspectives in the production of short-lived radionuclides for nuclear medicine applications by
means of 14 MeV neutron beams. 64Cu is, in fact, an emerging theranostic radionuclide currently produced with cyclotrons, irradiating very expensive 64Ni targets. From the achieved results, a prediction on the production of 64Cu with a highbrilliance 14 MeV neutron source, under construction at ENEA, was made
Light Dark Matter search with a positron beam
No full textAlthough the existence of Dark Matter has been confirmed by a variety of gravitational measurements, to date there are no conclusive indications about its particle nature. Light Dark Matter (LDM) particles, with mass in the range of 1 MeV–1000 MeV, represent a theoretically well-motivated solution for the Dark Matter puzzle. Among the LDM theories, the simplest model introduces a new light gauge boson called Dark Photon (A0). In this theory, the A0 can be generatedby the interaction of Standard Model charged particles with ordinary matter and subsequently decays into an LDM particle pair. In this scenario, an experiment making use of a positron beam impacting on a thick active target would have a unique discovery potential, since the positron annihilation process with atomic electrons provides an efficient mechanism for LDM generation. In this work, the feasibility and the potential of a missing energy experiment using a ∼10 GeV positron beam are discussed
Characterization of innovative pixel detectors with 3D technology
No full textDuring the high luminosity runs of the LHC collider, the detectors will face great challenges due to the increase in the particle density. Precise time information will be fundamental to maintain good detector performance. In this
article, a study of the characteristics of innovative 3D-trench pixel sensors with precise time measurement is presented. The sensors have been developed at the Fondazione Bruno Kessler in Trento by the TIMESPOT collaboration and the final detector should be capable of 20 ps time resolution, withstanding high radiation doses. In this work, first the static characteristics of the pixel sensors were measured, then their time resolution was studied with a laser system. Next, a sensor was tested with a 2 MeV energy proton beam at the Legnaro National Laboratories AN2000
accelerator facility. The time resolution has been extracted using an innovative time tag system, based on a thin layer of organic scintillator deposited above the detector
combined with a Silicon Photomultiplier. The uniformity of the response in the pixel active area has been studied with a precision of a few micrometers. Preliminary results are promising and justify further investigations on the capabilities of these sensors
Construction and assembly of the CGEM-IT innermost layer
No full textThe CGEM-IT, an innovative Cylindrical GEM Inner Tracker, is
the Italian proposal for the upgrade of the inner multilayer drift chamber of the BESIII experiment. The tracker consists of three independent layers, each with three multiplication stages. The strict requirements for resolution, size, and radiation length, as well as the need to withstand intercontinental shipping, require the use of advanced lightweight materials and state-of-the-art construction techniques. The construction of the innermost layer of the tracker is described in its entirety: from quality controls of the materials to assembly, which is accomplished with a custom vertical insertion machine
Coherent manipulation of molecular qudits by broadband NMR
No full textWe review recent results showing the capability of broadband Nuclear Magnetic Resonance (NMR) to coherently manipulate the state of multi-level molecular qudits with radiofrequency pulses. Several qubit-qudit systems have been studied, paving the way for the realization of quantum-error correction protocols. Here we focus on the recent prototypical [VO(TPP)] complex, a very promising system with long coherence times and strong hyperfine interaction
Ab initio circular dichroism with the yambo code: Beyond the independent particle approximation
No full textCircular dichroism (CD) spectroscopy is a useful technique for characterizing chiral molecules. It is more sensitive than total absorption to molecule conformation, and it is routinely used to identify enantiomers. We present here absorption and CD spectra within the Time-Dependent (TD) B3LYP approximation in c-GlyPhe, a cyclo-dipeptide containing an aromatic group. Results from codes in
localized basis-set (Orca and MolGW) are carefully compared with the novel TDB3LYP implementation we developed in the Yambo code, that uses a plane-wave basis set
Calibration of the Electric Field Detector for the CSES-02 satellite
No full textThe second China Seismo-Electromagnetic Satellite (CSES-02) will be equipped with the new Electric Field Detector (EFD-02), to measure the ionospheric electric field components at a Low Earth Orbit (LEO) over a wide frequency band (DC - 3.5 MHz) and with a high sensitivity (∼ 1 μV/m). EFD-02 will measure the voltages between different pairs of probes installed at the tips of four booms deployed from the satellite. Compared to the previous similar detectors on board CSES-01 and DEMETER missions, EFD-02 has a cutting-edge sensitivity that allows to observe more thoroughly the variation in the electric field under the magnetic field conditions encountered in its orbit around the Earth
Comparison of heavy-ion transport simulations for mean-field dynamics
No full textWithin the transport model evaluation project (TMEP) of simulations for heavy-ion collisions, the mean-field response is described here. Specifically, zero-sound propagation is considered for neutron-proton symmetric matter enclosed in a periodic box, at zero temperature and around normal density. The results of several transport codes belonging to two families (BUU-like and QMD-like codes) are compared among each other. QMD-like codes, using molecular dynamics methods, are characterized by large damping effects, attributable to the fluctuations inherent in their phase-space representation, and by slower density oscillations, as compared to BUU-like codes. The latter problem is mitigated in the more recent lattice formulation of some of the QMD codes
Status of the CLIR experiment at LNS
No full textTo investigate exotic cluster structures in neutron-rich nuclei via break-up reactions on a light target, the CLIR experiment was performed at INFN – Laboratori Nazionali del Sud (LNS). To this aim, a Radioactive Ion Beam (RIB) was produced, by means of the FRIBs@LNS facility, exploiting the In-Flight fragmentation technique: in this way, the obtained beam contains several radioactive ions of interest, such as 6He, 7,8,9Li, 11,12Be, 13,14,15B, 17C, and even the 16C and 10Be isotopes, for which cluster structures have already been studied at LNS. The isotopes of the cocktail beam were identified by means of the ΔE-ToF method, and
afterward break-up reactions were triggered by sending them on a (CH2)n polyethylene (protons) target; the reaction fragments were detected by the high-granularity femtoscope array FARCOS coupled with the CHIMERA 4π multidetector. In this paper an overview of the status of the experiment will be given, and in particular the calibration procedures developed for the tagging detector and for the FARCOS array will be described