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The slow solar wind belt in the quiet corona, observed with the Metis coronagraph on board Solar Orbiter on May 15, 2020, during the activity minimum of the cycle 24, in a field of view extending from 3.8 [Formula: see text] to 7.0 [Formula: see text], is formed by a slow and dense wind stream running along the coronal current sheet, accelerating in the radial direction and reaching at 6.8 [Formula: see text] a speed within 150 and 190 km s−1, depending on the assumptions on the velocity distribution of the neutral hydrogen atoms in the coronal plasma. The slow stream is separated by thin regions of high velocity shear from faster streams, almost symmetric relative to the current sheet, with peak velocity within 175 and 230 km s−1 at the same coronal level. The density–velocity structure of the slow wind zone is discussed in terms of the expansion factor of the open magnetic field lines that is known to be related to the speed of the quasi-steady solar wind, and in relation to the presence of a web of quasi-separatrix layers, S-web, the potential sites of reconnection that release coronal plasma into the wind. The parameters characterizing the coronal magnetic field lines are derived from 3D MHD model calculations. The S-web is found to coincide with the latitudinal region where the slow wind is observed in the outer corona and is surrounded by thin layers of open field lines expanding in a non-monotonic way.

Context.The fast solar wind is known to emanate from polar coronal holes.Aims.This Letter reports the first estimate of the expansion rate of polar coronal flows performed by the Metis coronagraph on board Solar Orbiter.Methods.By exploiting simultaneous measurements in polarized white light and ultraviolet intensity of the neutral hydrogen Lyman-αline, it was possible to extend observations of the outflow velocity of the main component of the solar wind from polar coronal holes out to 5.5 R⊙, the limit of diagnostic applicability and observational capabilities.Results.We complement the results obtained with analogous polar observations performed with the UltraViolet Coronagraph Spectrometer on board the SOlar and Heliospheric Observatory during the previous full solar activity cycle, and find them to be satisfactorily reproduced by a magnetohydrodynamic turbulence model.Conclusions.This suggests that the dissipation of 2D turbulence energy is a viable mechanism for coronal plasma heating and the subsequent acceleration of the fast solar wind.

Aims. We report observations of a unique, large prominence eruption that was observed in the He II 304 Å passband of the Extreme Ultraviolet Imager/Full Sun Imager telescope aboard Solar Orbiter on 15–16 February 2022. Methods. Observations from several vantage points – Solar Orbiter, the Solar-Terrestrial Relations Observatory, the Solar and Heliospheric Observatory, and Earth-orbiting satellites – were used to measure the kinematics of the erupting prominence and the associated coronal mass ejection. Three-dimensional reconstruction was used to calculate the deprojected positions and speeds of different parts of the prominence. Observations in several passbands allowed us to analyse the radiative properties of the erupting prominence. Results. The leading parts of the erupting prominence and the leading edge of the corresponding coronal mass ejection propagate at speeds of around 1700 km s−1 and 2200 km s−1, respectively, while the trailing parts of the prominence are significantly slower (around 500 km s−1). Parts of the prominence are tracked up to heights of over 6 R⊙. The He II emission is probably produced via collisional excitation rather than scattering. Surprisingly, the brightness of a trailing feature increases with height. Conclusions. The reported prominence is the first observed in He II 304 Å emission at such a great height (above 6 R⊙).

Carbon fusion reactions $$^{12}$$ 12 C($$^{12}$$ 12 C,p)$$^{23}$$ 23 Na and $$^{12}$$ 12 C($$^{12}$$ 12 C,$$\alpha $$ α )$$^{20}$$ 20 Ne play a key role in the evolution of massive stars and in explosive scenarios such as type-Ia supernovae and super-bursts in binary stars. A direct determination of their cross sections is extremely challenging and discrepancies exist between different data sets in the literature. Here we report the results of a direct measurement performed at the CIRCE Tandem Accelerator Laboratory in Caserta (Italy), using $$\varDelta E-E$$ Δ E - E detectors for unambiguous charge identification. Cross sections were measured in the energy range $$E_{\mathrm{c.m.}} =2.51{-}4.36$$ E c . m . = 2.51 - 4.36 MeV with energy steps between 10 and 25 keV in the centre of mass. To our knowledge these represent the finest energy steps to date. Results are presented in the form of partial and summed astrophysical $${\tilde{S}}$$ S ~ -factors for individual proton- and $$\alpha $$ α -particle channels. Branching ratios of individual proton- and $$\alpha $$ α -particle groups were found to vary significantly with energy. Angular distributions, albeit limited to three angles, were also found to be non-isotropic, which could be a potential explanation for the discrepancies observed among different data sets. Further efforts are ongoing to extend measurements to lower energies.

On February 12, 2021 two subsequent eruptions occurred above the West limb, as seen along the Sun-Earth line. The first event was a typical slow Coronal Mass Ejection (CME), followed $\sim 7$ hours later by a smaller and collimated prominence eruption, originating Southward with respect to the CME, followed by a plasma blob. These events were observed not only by SOHO and STEREO-A missions, but also by the suite of remote sensing instruments on-board Solar Orbiter (SolO). This work shows how data acquired by the Full Sun Imager (FSI), Metis coronagraph, and Heliospheric Imager (SoloHI) from the SolO perspective can be combined to study the eruptions and the different source regions. Moreover, we show how Metis data can be analyzed to provide new information about solar eruptions. Different 3D reconstruction methods were applied to the data acquired by different spacecraft including remote sensing instruments on-board SolO. Images acquired by both Metis channels in the Visible Light (VL) and H I Lyman$-\alpha$ line (UV) were combined to derive physical information on the expanding plasma. The polarization ratio technique was also applied for the first time to the Metis images acquired in the VL channel. The two eruptions were followed in 3D from their source region to their expansion in the intermediate corona. Thanks to the combination of VL and UV Metis data, the formation of a post-CME Current Sheet (CS) was followed for the first time in the intermediate corona. The plasma temperature gradient across a post-CME blob propagating along the CS was also measured for the first time. Application of the polarization ratio technique to Metis data shows that, thanks to the combination of four different polarization measurements, the errors are reduced by $\sim 5-7$\%, thus better constraining the 3D distribution of plasma., Comment: 15 pages, 14 figures, accepted for publication on A&A

Context. Solar Orbiter, the new-generation mission dedicated to solar and heliospheric exploration, was successfully launched on February 10, 2020, 04:03 UTC from Cape Canaveral. During its first perihelion passage in June 2020, two successive interplanetary coronal mass ejections (ICMEs), propagating along the heliospheric current sheet (HCS), impacted the spacecraft. Aims. This paper addresses the investigation of the ICMEs encountered by Solar Orbiter on June 7−8, 2020, from both an observational and a modeling perspective. The aim is to provide a full description of those events, their mutual interaction, and their coupling with the ambient solar wind and the HCS. Methods. Data acquired by the MAG magnetometer, the Energetic Particle Detector suite, and the Radio and Plasma Waves instrument are used to provide information on the ICMEs’ magnetic topology configuration, their magnetic connectivity to the Sun, and insights into the heliospheric plasma environment where they travel, respectively. On the modeling side, the Heliospheric Upwind eXtrapolation model, the 3D COronal Rope Ejection technique, and the EUropean Heliospheric FORecasting Information Asset (EUHFORIA) tool are used to complement Solar Orbiter observations of the ambient solar wind and ICMEs, and to simulate the evolution and interaction of the ejecta in the inner heliosphere, respectively. Results. Both data analysis and numerical simulations indicate that the passage of two distinct, dynamically and magnetically interacting (via magnetic reconnection processes) ICMEs at Solar Orbiter is a possible scenario, supported by the numerous similarities between EUHFORIA time series at Solar Orbiter and Solar Orbiter data. Conclusions. The combination of in situ measurements and numerical simulations (together with remote sensing observations of the corona and inner heliosphere) will significantly lead to a deeper understanding of the physical processes occurring during the CME-CME interaction.

The elastic scattering in the reaction $$^{7}$$ 7 Li+$$^{208}$$ 208 Pb was investigated in the bombarding energy range from 25 to 39 MeV. The real and imaginary parts of the optical potential were analyzed by using a phenomenological potential. A dispersion relation analysis is presented in order to investigate the threshold anomaly effect. It is concluded that $$^{7}$$ 7 Li has an intermediate behavior between the tightly bound nuclei such as $$^{16}$$ 16 O and the loosely bound nuclei such as $$^{6}$$ 6 Li where the lack of the threshold anomaly is unambiguously observed. Reaction cross sections are also extracted from the elastic scattering data and its comparison with the ones of other systems has been performed to draw hints on the effect of the breakup channel.

Context.The Metis coronagraph on board Solar Orbiter offers a new view of coronal mass ejections (CMEs), observing them for the first time with simultaneous images acquired with a broad-band filter in the visible-light interval and with a narrow-band filter around the H ILy-αline at 121.567 nm, the so-called Metis UV channel.Aims.We show the first Metis observations of a CME, obtained on 16 and 17 January 2021. The event was also observed by the EUI/FSI imager on board Solar Orbiter, as well as by other space-based coronagraphs, such as STEREO-A/COR2 and SOHO/LASCO/C2, whose images are combined here with Metis data.Methods.Different images are analysed here to reconstruct the 3D orientation of the expanding CME flux rope using the graduated cylindrical shell model. This also allows us to identify the possible location of the source region. Measurements of the CME kinematics allow us to quantify the expected Doppler dimming in the Ly-αchannel.Results.Observations show that most CME features seen in the visible-light images are also seen in the Ly-αimages, although some features in the latter channel appear more structured than their visible-light counterparts. We estimated the expansion velocity of this event to be below 140 km s−1. Hence, these observations can be understood by assuming that Doppler dimming effects do not strongly reduce the Ly-αemission from the CME. These velocities are comparable with or smaller than the radial velocities inferred from the same data in a similar coronal structure on the east side of the Sun.Conclusions.The first observations by Metis of a CME demonstrate the capability of the instrument to provide valuable and novel information on the structure and dynamics of these coronal events. Considering also its diagnostics capabilities regarding the conditions of the ambient corona, Metis promises to significantly advance our knowledge of such phenomena.

Background Crossover between direct oral anticoagulants (DOACs) in real-life setting has been under investigated, with electronic registry-based study missing minor bleedings and minor ischemic events. The purpose of this study was to evaluate the switch from a DOAC to another DOAC, the reasons and the clinical events which happened after the switch. Methods Patients (pts) receiving first DOAC prescription at the Anticoagulation Center from February 2018 to September 2019 were consecutively included and followed. Causes of switch/dosage change as well as events or adverse events not leading to switch were registered. Results Overall, 300 pts were included, mean age 79.3 ± 8.5, male 53.7% (n = 161). 220 pts were received DOAC being naïve (70.7%), while 88 (29.3%) transitioned from vitamin K antagonists. Mean follow-up was 1.5 years from first DOAC prescription. Most prescribed DOACs was rivaroxaban (n = 107), followed by apixaban (n = 82), edoxaban (n = 59) and dabigatran (n = 52). No significant differences in age, gender, CHA2DS2VASc or HASBLED score was detected. Throughout follow-up, 61 patients (20.3%) needed changes in anticoagulation regimen. 24 patients changed DOAC dosage (8%), while 40 patients changed anticoagulants (13.3%), 39 switched from DOAC to another DOAC, 1 from DOAC to warfarin. Annual DOAC-to-DOAC switching rate was 15.0% (95%CI 10.8-20.3). Prevalence of switch varied across DOACs: 28.8% of pts taking dabigatran switched vs 11.0%, 10.2% and 9.3% of those taking apixaban, edoxaban and rivaroxaban respectively (p Conclusion Minor bleeding and non cardiovascular adverse events are the most common causes of switch, which has a rate as high as 15% year. Crossover between DOACs seems safe, and might therefore be considered after minor bleeding and non-cardiovascular adverse events

We present a new correlation method for deriving the F-corona intensity distribution, which is based on the analysis of the evolution of the total and polarized visible light (VL) images. We studied the one-month variation profiles of the total and polarized brightness acquired with Large Angle Spectrometric COronagraph (LASCO-C2) and found that in some regions they are highly correlated. Assuming that the F-corona does not vary significantly on a timescale of one month, we estimated its intensity in the high-correlation regions and reconstructed the corresponding intensity maps both during the solar-minimum and solar-maximum periods. Systematic uncertainties were estimated by performing dedicated simulations. We compared the resulting F-corona images with those determined using the inversion technique and found that the correlation method provides a smoother intensity distribution. We also obtained that the F-corona images calculated for consecutive months show no significant variation. Finally, we note that this method can be applied to the future high-cadence VL observations carried out with the Metis/Solar Orbiter coronagraph., 16 pages, 21 figures

The 12C(12C,p)23Na and 12C(12C, $\alpha$ )20Ne fusion reactions are among the most important in stellar evolution since they determine the destiny of massive ( $ M \simeq 8-10 M_{\odot}$ ) stars. However, experimental low-energy investigations of such reactions are significantly hampered by ubiquitous natural hydrogen and deuterium contaminants in the carbon targets. The associated beam-induced background completely masks the reaction products of interest thus preventing cross-section measurements at the relevant energies of astrophysical interest, $E_{\mathrm{cm}} < 2$ MeV. In this work, we report about an investigation aimed at assessing possible deuterium reductions on both natural graphite and Highly Ordered Pyrolytic Graphite targets as a function of target temperature. Our results indicate that reductions up to about 80% can be attained on both targets in the temperature range investigated, $ T \simeq 200-1200 {}^{\circ}$ C. A further reduction by a factor of 2.5 in absolute deuterium content is observed when the scattering chamber is surrounded by a dry nitrogen atmosphere so as to minimise light-particles uptake within the chamber rest gas (and thus on target) through air leaks. The results from this study will inform the choice of optimal experimental conditions and procedures for improved measurements of the 12C + 12C reactions cross-sections at the low energies of astrophysical interest.

7Be(p, $\gamma$ )8B has an important role in nuclear astrophysics, having a direct impact on both the high energy component of solar neutrinos and the 7Li abundance after the Big Bang Nucleosynthesis. All direct measurements providing useful information on this reaction so far used the same approach, i.e. a proton beam on a radioactive 7Be target. The overall precision and accuracy of the estimate of the astrophysical rate of this reaction are limited by the discrepancy between the results of existing measurements, possibly due to the complicated stoichiometry and beam induced deterioration of the radioactive targets. The ERNA (European Recoil separator for Nuclear Astrophysics) collaboration planned a new experiment in inverse kinematics exploiting the intense 7Be beam available at CIRCE (Center for Isotopic Research on Cultural and Environmental heritage), Caserta, Italy. The 8B recoils are produced in a windowless hydrogen gas target and detected after the efficient mass separation provided by ERNA. Here we present the commissioning of the experimental setup and a first cross section measurement at $E_{\mathrm{cm}}\approx 812$ keV.

The excitation of the Dynamical Dipole mode along the fusion path was investigated for the first time in the formation of a heavy composite system in the A~190 mass region, in fusion-evaporation and fission events. The composite system was formed at identical conditions of excitation energy and spin from two reactions with different charge asymmetry: the charge asymmetric 40Ca + 152Sm and the nearly charge symmetric 48Ca + 144Sm at E lab =11 and 10.1 MeV/nucleon, respectively. In this paper, we report the results on fusion evaporation events and the preliminary analysis on fission channel.

We discuss new results concerning the investigation of the 19F(p, α 0)16O reaction at very low energies (0.6-0.2 MeV). This reaction is important both in Nuclear Astrophysics, because it closes the CNOF cycle and it is an important fluorine destruction channel in hydrogen rich stellar environments, and in Nuclear Structure, because it allows to study the spectroscopy of the self-conjugated 20Ne compound nucleus. Despite its importance, very few direct data have been published at low energies in the literature. Our work allowed to deduce the S-factor down to ≈ 0.2 MeV and to point out the role played by broad resonances at low energies. The experimental S- factor is ≈1.5-2 times larger than non-resonant extrapolations reported by nacre with potentially important astrophysical consequences.

A new detection array called GASTLY (GAs-Silicon Two-Layer sYstem) has been designed to detect and identify low-energy light particles emitted in nuclear reactions of astrophysical interest. Devoted to the measurement of nanobarn cross-sections, the system is optimised for large solid angle coverage and for low-energy detection thresholds. The array consists of eight modules, each comprising an ionisation chamber and a large area silicon strip detector. Its modularity and versatility allow for use in a variety of experiments. Here we report on the performance of the array as obtained during its commissioning phase with standard $\alpha$ -particle sources and during in-beam tests with an intense 12C beam. Typical energy resolutions $\Delta E(\mathrm{FWHM})/E$ of about 3% and 2% were obtained for the ionisation chambers and the silicon detectors, respectively. The status of the development of individual strip readout, based on ASIC technology, is also presented.

C-12(alpha, gamma)O-16 cross section plays a key-role in the stellar evolution and nucleosynthesis of massive stars. Hence, it must be determined with the precision of about 10% at the relevant Gamow energy of 300 keV. The ERNA (European Recoil mass separator for Nuclear Astrophysics) collaboration measured, for the first time, the total cross section of C-12(alpha, gamma)O-16 by means of the direct detection of the O-16 ions produced in the reaction down to an energy of E-cm = 1.9 MeV. To extend the measurement at lower energy, it is necessary to limit the extension of the He gas target. This can be achieved using a supersonic jet, where the oblique shock waves and expansion fans formed at its boundaries confine the gas, which can be efficiently collected using a catcher. A test version of such a system has been designed, constructed and experimentally characterized as a bench mark for a full numerical simulation using FV (Finite Volume) methods. The results of the commissioning of the jet test version and the design of the new system that will be used in combination with ERNA are presented and discussed.

The 19 F(p, α 0 ) 16 O reaction at low energies plays an important role in fundamental physics. In particular in nuclear astrophysics it represents, together with the 19 F(p, γ ) 20 Ne reaction, the crossing point between the CNO and the NeNa cycles in stars. Further, in hydrogen-rich stellar environments, it is the most important fluorine destruction channel. In this paper we report new measurements on the 19 F(p, α 0 ) 16 O reaction at deeply sub-Coulomb energies (0.2–0.6 MeV), a region where, despite the key role of this reaction, very few and old data are reported. The deduced astrophysical S -factor is ≈ 1.5 – 2 times larger than currently adopted extrapolations with possibly important astrophysical consequences.

The excitation of the dynamical dipole mode along the fusion path was investigated for the first time in the formation of a heavy compound nucleus in the A ∼ 190 mass region. The compound nucleus was formed at identical conditions of excitation energy and spin from two entrance channels: the charge-asymmetric 40 Ca + 152 Sm and the nearly charge-symmetric 48 Ca + 144 Sm at E lab = 11 and 10.1 MeV / nucleon, respectively. High-energy γ rays and light charged particles were measured in coincidence with evaporation residues by means of the MEDEA multidetector array (Laboratori Nazionali del Sud, Italy) coupled to four parallel plate avalanche counters. The charged particle multiplicity spectra and angular distributions were used to pin down the average excitation energy, the average mass, and the average charge of the compound nucleus. The γ -ray multiplicity spectrum and angular distribution related to the nearly charge-symmetric channel were employed to obtain new data on the giant dipole resonance in the compound nucleus. The dynamical dipole mode excitation in the charge-asymmetric channel was evidenced, in a model-independent way, by comparing the γ -ray multiplicity spectra and angular distributions of the two entrance channels with each other. Calculations of the dynamical dipole mode in the 40 Ca + 152 Sm channel, based on a collective bremsstrahlung analysis of the reaction dynamics, are presented. Possible interesting implications in the superheavy-element quest are discussed.

Background: The origin of fluorine is a widely debated issue. Nevertheless, the $^{15}\mathrm{N}(\ensuremath{\alpha},\ensuremath{\gamma})^{19}\mathrm{F}$ reaction is a common feature among the various production channels so far proposed. Its reaction rate at relevant temperatures is determined by a number of narrow resonances together with the direct capture and the tails of the two broad resonances at ${E}_{\mathrm{c}.\mathrm{m}.}=1323$ and 1487 keV.Purpose: The broad resonances widths, ${\mathrm{\ensuremath{\Gamma}}}_{\ensuremath{\gamma}}$ and ${\mathrm{\ensuremath{\Gamma}}}_{\ensuremath{\alpha}}$, have to be measured with adequate precision in order to better determine their contribution to the $^{15}\mathrm{N}(\ensuremath{\alpha},\ensuremath{\gamma})^{19}\mathrm{F}$ stellar reaction rate.Methods: Measurement through the direct detection of the $^{19}\mathrm{F}$ recoil ions with the European Recoil separator for Nuclear Astrophysics (ERNA) were performed. The reaction was initiated by a $^{15}\mathrm{N}$ beam impinging onto a $^{4}\mathrm{He}$ windowless gas target. The observed yield of the resonances at ${E}_{\mathrm{c}.\mathrm{m}.}=1323$ and 1487 keV is used to determine their widths in the $\ensuremath{\alpha}$ and $\ensuremath{\gamma}$ channels.Results: We show that a direct measurement of the cross section of the $^{15}\mathrm{N}(\ensuremath{\alpha},\ensuremath{\gamma})^{19}\mathrm{F}$ reaction can be successfully obtained with the recoil separator ERNA, and the widths ${\mathrm{\ensuremath{\Gamma}}}_{\ensuremath{\gamma}}$ and ${\mathrm{\ensuremath{\Gamma}}}_{\ensuremath{\alpha}}$ of the two broad resonances have been determined. While a fair agreement is found with earlier determination of the widths of the 1487 keV resonance, a significant difference is found for the 1323 keV resonance ${\mathrm{\ensuremath{\Gamma}}}_{\ensuremath{\alpha}}$.Conclusions: The revision of the widths of the two more relevant broad resonances in the $^{15}\mathrm{N}(\ensuremath{\alpha},\ensuremath{\gamma})^{19}\mathrm{F}$ reaction presented in this work is the first step toward a more firm determination of the reaction rate. At present, the residual uncertainty at the temperatures of the $^{19}\mathrm{F}$ stellar nucleosynthesis is dominated by the uncertainties affecting the direct capture component and the 364 keV narrow resonance, both so far investigated only through indirect experiments.

The excitation of the Dynamical Dipole mode along the fusion path was investigated for the first time in the formation of a heavy compound nucleus in the A~190 mass region. The compound nucleus was formed at identical conditions of excitation energy and spin from two entrance channels having different charge asymmetry: the charge asymmetric 40 Ca + 152 Sm and the nearly charge symmetric 48 Ca + 144 Sm at Elab =11 and 10.1 MeV/nucleon, respectively. Both fusion–evaporation and fission events were studied simultaneously for the first time. The Dynamical Dipole mode excitation in the charge asymmetric channel was evidenced, in a model-independent way, by comparing the γ -ray multiplicity spectra and angular distributions of the two entrance channels with each other.

12C(α, γ)16O cross section plays a key-role in the stellar evolution and nucleosynthesis of massive stars. Hence, it must be determined with the precision of about 10% at the relevant Gamow energy of 300 keV. The ERNA (European Recoil mass separator for Nuclear Astrophysics) collaboration measured, for the first time, the total cross section of 12C(α, γ)16O by means of the direct detection of the 16O ions produced in the reaction down to an energy of Ecm = 1.9 MeV. To extend the measurement at lower energy, it is necessary to limit the extension of the He gas target. This can be achieved using a supersonic jet, where the oblique shock waves and expansion fans formed at its boundaries confine the gas, which can be efficiently collected using a catcher. A test version of such a system has been designed, constructed and experimentally characterized as a bench mark for a full numerical simulation using FV (Finite Volume) methods. The results of the commissioning of the jet test version and the design of the new system that will be used in combination with ERNA are presented and discussed.

The excitation of the dynamical dipole mode along the fusion path was investigated for the first time in the formation of a heavy compound nucleus in the $A\ensuremath{\sim}190$ mass region. The compound nucleus was formed at identical conditions of excitation energy and spin from two entrance channels: the charge-asymmetric $^{40}\mathrm{Ca}+^{152}\mathrm{Sm}$ and the nearly charge-symmetric $^{48}\mathrm{Ca}+^{144}\mathrm{Sm}$ at ${E}_{\text{lab}}=11$ and 10.1 MeV/nucleon, respectively. High-energy $\ensuremath{\gamma}$ rays and light charged particles were measured in coincidence with evaporation residues by means of the MEDEA multidetector array (Laboratori Nazionali del Sud, Italy) coupled to four parallel plate avalanche counters. The charged particle multiplicity spectra and angular distributions were used to pin down the average excitation energy, the average mass, and the average charge of the compound nucleus. The $\ensuremath{\gamma}$-ray multiplicity spectrum and angular distribution related to the nearly charge-symmetric channel were employed to obtain new data on the giant dipole resonance in the compound nucleus. The dynamical dipole mode excitation in the charge-asymmetric channel was evidenced, in a model-independent way, by comparing the $\ensuremath{\gamma}$-ray multiplicity spectra and angular distributions of the two entrance channels with each other. Calculations of the dynamical dipole mode in the $^{40}\mathrm{Ca}+^{152}\mathrm{Sm}$ channel, based on a collective bremsstrahlung analysis of the reaction dynamics, are presented. Possible interesting implications in the superheavy-element quest are discussed.

The excitation of the dynamical dipole mode along the fusion path was investigated in the formation of a heavy compound nucleus in the A=190 mass region. To form the compound nucleus, the 40 Ca + 152 Sm and 48 Ca + 144 Sm reactions were employed at Elab =11 and 10.1 MeV/nucleon, respectively. Both fusion–evaporation and fission events were studied simultaneously for the first time. Our results for evaporation and fission events (preliminary) show that the dynamical dipole mode survives in reactions involving heavier nuclei than those studied previously.

We describe the experimental set-up of the Radioactive Ion Beam (RIB) in-flight facility EXOTIC consisting of: (a) two position-sensitive Parallel Plate Avalanche Counters (PPACs), dedicated to the event-by-event tracking of the produced RIBs and to time of flight measurements and (b) the new high-granularity compact telescope array EXPADES (EXotic PArticle DEtection System), designed for nuclear physics and nuclear astrophysics experiments employing low-energy light RIBs. EXPADES consists of eight Δ E – E res telescopes arranged in a cylindrical configuration around the target. Each telescope is made up of two Double Sided Silicon Strip Detectors (DSSSDs) with a thickness of 40/60 μm and 300 μm for the Δ E and Eres layer, respectively. Additionally, eight ionization chambers were constructed to be used as an alternative Δ E stage or, in conjunction with the entire DSSSD array, to build up more complex triple telescopes. New low-noise multi-channel charge-sensitive preamplifiers and spectroscopy amplifiers, associated with constant fraction discriminators, peak-and-hold and Time to Amplitude Converter circuits were developed for the electronic readout of the Δ E stage. Application Specific Integrated Circuit-based electronics was employed for the treatment of the Eres signals. An 8-channel, 12-bit multi-sampling 50 MHz Analog to Digital Converter, a Trigger Supervisor Board for handling the trigger signals of the whole experimental set-up and an ad hoc data acquisition system were also developed. The performance of the PPACs, EXPADES and of the associated electronics was obtained offline with standard α calibration sources and in-beam by measuring the scattering process for the systems 17O+58Ni and 17O+208Pb at incident energies around their respective Coulomb barriers and, successively, during the first experimental runs with the RIBs of the EXOTIC facility.

The energy and angular distributions of $^{3}\mathrm{He}$ and $^{4}\mathrm{He}$ ions produced in the $^{7}\mathrm{Be}\phantom{\rule{4pt}{0ex}}+\phantom{\rule{4pt}{0ex}}^{58}\mathrm{Ni}$ reaction at a bombarding energy of 22 MeV have been measured for the first time. The yield of the heavier helium isotope was four to five times more abundant than that of its lighter counterpart, ruling out the possibility that in this energy range the $^{7}\mathrm{Be}$ reaction dynamics is dominated by the exclusive breakup process $^{7}\mathrm{Be}\phantom{\rule{4pt}{0ex}}\ensuremath{\rightarrow}{\phantom{\rule{4pt}{0ex}}}^{3}\mathrm{He}\phantom{\rule{4pt}{0ex}}+\phantom{\rule{4pt}{0ex}}^{4}\mathrm{He}$ (${S}_{\ensuremath{\alpha}}=1.586$ MeV). Extensive kinematic and theoretical calculations suggest that the $^{3}\mathrm{He}$ ions mostly originate from the $^{4}\mathrm{He}$-stripping process and the $^{4}\mathrm{He}$ production is mainly triggered by the fusion-evaporation channel. The role played by the breakup, $^{3}\mathrm{He}$-stripping, $1n$-stripping, and $1n$-pickup processes is also discussed.

Twenty years ago the hypothesis was introduced that acupuncture stimulation may activate specific areas of the brain. However only recently this diagnostic procedure has become more and more appealing for investigating some crucial aspects of acupuncture, such as the comparison between “verum” and “sham” acupuncture, the intensity of stimulation (with or without deqi effect), the differences between points located on the same meridian or on different meridians. Most studies of the literature suggest that acupuncture can modulate the activity of the brain, both with activating and deactivating specific areas. With regard to ear acupuncture it is not clear to us why in the same period only three fMRI studies have been published applying this technique, one in 2002 and two in 2014. In the first study Dr. David Alimi demonstrated with a Block Design that auricular stimulation of the thumb point activated the somesthetic area S1 contralaterally in 6 subjects and bilaterally in 3 subjects. In the second study, performed by Romoli and coll., for the first time the specificity of auricular points was explored, choosing two points (thumb and brain stem) which are topographically distant from each other and have different therapeutic indications. In the same year a second study was organized by Dr. Alimi and Dr. Bahr the purpose of which was to evaluate the differences stimulating the knee point according to Nogier-Bahr or according to the current Chinese auricular map. The aim of this article is to promote further investigations with fMRI on a series of fundamental or particularly active points regulating the neuroendocrine and vegetative functions such as Nogier’s Zero point, Shenmen, Endocrine, Occiput etc.

The dynamical dipole mode was investigated in the mass region of the 192Pb compound nucleus, by using the 40Ca + 152Sm and 48Ca + 144Sm reactions at Elab=11 and 10.1 MeV/nucleon, respectively. Both fusion-evaporation and fission events were studied simultaneously for the first time. Our results for evaporation and fission events (preliminary) show that the dynamical dipole mode survives in reactions involving heavier nuclei than those studied previously.

Inclusive and exclusive cross sections have been measured for different projectile breakup channels. It is observed that the inclusive cross sections are larger than the exclusive ones. It is found that other processes, besides the direct breakup channel, significantly contribute to the inclusive channels. A clear alpha+x cluster structure has been found from coincidence data.

We investigated the reaction induced by the Radioactive Ion Beam 7Be on the closed proton shell nucleus 58Ni at 22.0 MeV bombarding energy. The 7Be beam was produced by means of the in-flight technique with the facility EXOTIC at INFN-LNL (Italy). Charged reaction products were mass and charge identified in a rather wide angular range and their energy distributions were analyzed to infer some information on the production mechanism. The relevance of direct processes, especially 3He- and 4He-stripping, as well as compound nucleus reactions is critically reviewed.

The study of reactions induced by exotic weakly bound nuclei at energies around the Coulomb barrier had attracted a large interest in the last decade, since the features of these nuclei can deeply affect the reaction dynamics. The discrimination between different reaction mechanisms is, in general, a rather difficult task. It can be achieved by using detector arrays covering high solid angle and with high granularity that allow to measure the reaction products and, possibly, coincidences between them, as, for example, recently done for stable weakly bound nuclei [1, 2]. We investigated the collision of the weakly bound nucleus 7Be on a 58Ni target at the beam energy of 1.1 times the Coulomb barrier, measuring the elastic scattering angular distribution and the energy and angular distributions of 3He and 4He. The 7Be radioactive ion beam was produced by the facility EXOTIC at INFN-LNL with an energy of 22 MeV and an intensity of ~3×105 pps. Results showed that the 4He yeld is about 4 times larger than 3He yield, suggesting that reaction mechanisms other than the break-up mostly produce the He isotopes. Theoretical calculations for transfer channels and compound nucleus reactions suggest that complete fusion accounts for (41±5%) of the total reaction cross section extracted from optical model analysis of the elastic scattering data, and that 3He and 4He stripping are the most populated reaction channels among direct processes. Eventually estimation of incomplete fusion contributions to the 3,4He production cross sections was performed through semi-classical calculations with the code PLATYPUS [3].

As a preliminary step towards measurements of the 12C +12 C reactions at astrophysical energies, we investigate the behaviour of targets under beam bombardment, specifically the quantitative relation between hydrogen and deuterium content of different carbon targets and target temperature. Experiments have taken place at the CIRCE accelerator in Caserta, Italy and preliminary results are presented here.

International audience; The collisional width of a spectral line takes part in the frequency re- distribution of the scattered radiation in the line. Within the impact approximation, collisional line broadening parameters (widths and shifts), depolarization and polariza- tion transfer rates seem very similar: both include the effect of collisional transitions between the Zeeman sublevels of a given level, or between fine or hyperfine structure levels of a given term. However, there are important differences. On the one hand, for line broadening, the two levels connected by the radiative transition contribute to the broadening. There is also an interference term between the two levels of the line, which can be very important for collisions with neutral hydrogen. On the other hand, only one level or two close levels are concerned in the depolarization. Another difference lies in the fact that elastic cross-sections of the two levels contribute to the line broadening, whereas they do not contribute to the depolarization. The possibility to find some the- oretical relationships concerning depolarization versus collisional broadening will be shown to be impossible. The perturbation expansion of the collisional S matrix and the Van der Waals interaction potential are recalled to be unsuitable, since all the derived parameters are too small (by approximately a factor 2). Finally, in the light of a very recent paper, numerical relationships between line widths and level depolarization rates will be quoted.

International audience; This work is aimed to the interpretation of the linear polarization spectrum observed in the “Second Solar Spectrum”, likely to provide information on the magnetic field vector or on the medium anisotropy. The lines are formed by scattering. Far wings due to partial redistribution are observed in 30% of the spectral lines (Belluzzi & Landi Degl’Innocenti, 2009, A&A, 495, 577). It will be first shown that the second-order perturbation theory is unable to fully describe the frequency redistribution in the far wings. Rayleigh/Raman scattering appears at fourth order. The development has then to be pursued beyond. It will be shown how this series development can be transformed into an infinite sum, which can then be evaluated at infinity, thus overcoming the Markov approximation. In a second part, addressing the problem of the scattering by multilevel atoms, the different processes entering the redistribution will be discussed, which are namely the Rayleigh/Raman scattering and the coupling between the frequency coherence and the Doppler effect in the laboratory reference frame. These two processes are different, but it will be shown they are weighted by part of the same collisions in the redistribution description. The consequences of this will be discussed, in terms of redistribution model. It will be shown that the statistical equilibrium equations have to be resolved for each atomic velocity class, leading to departures from the Maxwellian distribution in the excited states.