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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.

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.

In recent years research explored different acupuncture stimulation techniques but interest has focused primarily on somatic acupuncture and on a limited number of acupoints. As regards ear Acupuncture (EA) there is still some criticism about the clinical specificity of auricular points/areas representing organs or structures of the body. The aim of this study was to verify through (Functional magnetic resonance imaging) fMRI the hypothesis of EA point specificity using two auricular points having different topographical locations and clinical significance. Six healthy volunteers underwent two experimental fMRI sessions: the first was dedicated to the stimulation of Thumb Auricular Acupoint (TAA) and the second to the stimulation of Brain Stem Auricular Acupoint (BSAA). The stimulation of the needle placed in the TAA of the left ear produced an increase in activation bilaterally in the parietal operculum, region of the secondary somatosensory area SII. Stimulation of the needle placed in the BSAA of the left ear showed a pattern that largely overlapped regions belonging to the pain matrix, as shown to be involved in previous somatic acupuncture studies but with local differences in the left amygdala, anterior cingulate cortex, and cerebellum. The differences in activation patterns between TAA and BSAA stimulation support the specificity of the two acupoints. Moreover, the peculiarity of the regions involved in BSAA stimulation compared to those involved in the pain matrix, is in accordance with the therapeutic indications of this acupoint that include head pain, dizziness and vertigo. Our results provide preliminary evidence on the specificity of two auricular acupoints; further research is warranted by means of fMRI both in healthy volunteers and in patients carrying neurological/psychiatric syndromes.

We developed a Monte-Carlo code for describing the reaction kinematics of the two-body direct processes employed of the EXOTIC beam-line of the Laboratori Nazionali di Legnaro (LNL) for the production of light weakly bound radioactive ion beams at energies of a few MeV/u. The program calculates the phase-space distribution of both primary and secondary beams at the target exit and uses these quantities to optimize the secondary beam selection with the EXOTIC spectrometer. The calculations have been performed and compared with the available experimental data for two reactions: (1)H(2)((17)O, (17)F)n and (3)He((6)Li, (8)B)n. (c) 2008 Elsevier B.V. All rights reserved.

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.

The β-decay of 102Sn was studied by using high-resolution germanium detectors as well as a Total Absorption Spectrometer (TAS). A decay scheme has been constructed based on the γ-γ coincidence data. The total experimental Gamow-Teller strength B GT exp of 102Sn was deduced from the TAS data to be 4.2(9). A search for β-delayed γ-rays of 100Sn decay remained unsuccessful. However, a Gamow-Teller hindrance factor h=2:2(3), and a cross-section of about 3 nb for the production of 100Sn in fusion-evaporation reaction between 58Ni beam and 50Cr target have been estimated from the data on heavier tin isotopes. The estimated hindrance factor is similar to the values derived for lower shell nuclei.

Beta decays of 94,96Ag and 103Sn nuclei into proton channels have been studied in the recent experiments at the GSI-ISOL facility. New efficient and chemically selective ion sources provided the highest yields of light silver and tin isotopes. Large arrays of germanium γ-ray and silicon charged-particle detectors, as well as a total absorption spectrometer (TAS) were used to measure β-proton, proton-γ, β-proton-γ and proton-γ-γ spectra. For the decay of 94Ag, we observed high-spin states in 93Rh populated by proton emission following β decay, whose largest spin value (≥39/2) yields an experimental proof for the existence of a second high-spin isomer in 94Ag with I≥17. Its β-decay energy is at least 16.8 MeV, corresponding to an excitation energy ≥5.5 MeV. For 103Sn, the γ rays measured in coincidence with β-delayed protons allowed us to establish the β-decay properties of this isotope. In particular, a QEC value of 7.5(6) MeV is derived from the intensity ratio of protons that are preceded either by EC or by β+ decays and populate the 2+ state in 102Cd.

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.

Non-radiative transitions in nuclear capture reactions between light nuclei play a relevant role in stellar nuclear astrophysics, where nuclear processes occur at typical energies from tens to hundreds of keV. At higher energies, instead, the E0 contributions may be shadowed by more intense transitions. The experimental study of E0 transitions requires a specific detection setup, able to uniquely identify events where an electron-positron pair is produced. A compact ΔE-E charged-particle spectrometer based on two silicon detectors has been designed to be installed in the jet gas target chamber of the recoil mass separator ERNA (European Recoil separator for Nuclear Astrophysics) at the CIRCE laboratory of Caserta, Italy. The detector design, its performances and the first foreseen applications are described.

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.

Proton elastic scattering and inelastic scattering to the first excited state of 6He have been measured over a wide angular range using a 40.9A MeV 6He beam. The data have been analyzed with a fully microscopic model of proton-nucleus scattering using 6He wave functions generated from large space shell model calculations. The inelastic scattering data show a remarkable sensitivity to the halo structure of 6He., Comment: 9 pages, 3 figures. RevTeX. Replaced figure 3 with updated figure

Resumen Introduccion Contar con un sistema fiable de transcripcion de puntos del pabellon auditivo resulta esencial para el diagnostico auricular. Ademas, la transcripcion correcta y el registro de estos puntos ayuda al medico a valorar si el paciente se esta beneficiando del tratamiento. En el pasado se han propuesto distintos sistemas graficos bidimensionales para la transcripcion de los puntos auriculares. Objetivo Validar un nuevo sistema de transcripcion de puntos: el sectograma auricular. Metodo Despues de participar en un curso teorico y practico sobre diagnostico auricular y auriculoterapia, 385 medicos realizaron el siguiente ejercicio de transcripcion: se proyectaron sobre una pantalla 2 juegos de puntos (I y II) de forma consecutiva. Cada juego constaba de 3 puntos situados en 3 partes diferentes del pabellon auditivo (helix, antehelix y lobulo de la oreja). Los medicos debian trasladar los puntos de ambos juegos en cualquier orden al sectograma o a una representacion del pabellon auditivo sin subdivisiones en sectores. Ambos modelos se compararon en cuanto a media de puntos correctamente trasladados, asi como a proporciones relativas en las distintas partes del pabellon auditivo. El mismo procedimiento se aplico para el numero medio total de sectores correctamente identificados y sus proporciones. Resultados El numero medio total de puntos correctamente trasladados utilizando el sectograma fue significativamente superior (p Conclusiones El sectograma auricular permite a los acupuntores realizar una transcripcion precisa de los puntos y las zonas auriculares con fines diagnosticos y terapeuticos.

Introduction A reliable system of transcription of the points mapped on the outer ear is essential for auricular diagnosis. Moreover the correct transcription and recording of these points helps the physician to understand if a patient's condition is going to improve with therapy. Several bi-dimensional graphic systems have been proposed in the past for transcribing the auricular points. Objective To validate a new system of transcription of points: the Auricular Sectogram. Methods After attending a theoretical-practical course of auricular diagnosis and therapy 385 physicians were asked to participate in the following transcription exercise: two sets of points, I and II, were projected onto a screen one after the other. Each set was composed of 3 points located on 3 different parts of the pinna (helix, anthelix and earlobe). The physicians were asked to transcribe the points of sets I and II in random order on the Sectogram or on a map of the auricle without subdivision into sectors. These two modalities were compared for total average number of correct transcriptions as well as for their relative proportions on the different parts of the ear. The same procedure was adopted with the average total number of correctly identified sectors and their proportions. Results The total average number of correctly transcribed points was significantly higher using the Sectogram (p Conclusions The Auricular Sectogram allows practitioners to transcribe more precisely the site of auricular points and areas for diagnostic and therapeutic purposes

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 spectra of the γ-rays emitted in the 35Cl + 92Mo reaction at incident energy E = 260 MeV were measured in coincidence with the ejectiles produced in dissipative reaction events. The cumulative energy spectrum of the γ-rays coming from the decay of the ejectiles was calculated within the statistical model and its comparison to the experimental spectrum evidences an excess in the data for Eγ = 8 to 12 MeV. Such an excess, fitted with a Lorentz curve, is attributed to the preequilibrium GDR γ-decay of the intermediate dinuclear system. The centroid energy of the Lorentz curve corresponds to a dipole oscillation along the symmetry axis of the system and its width is found to be comparable to that of the ground state GDR low energy component of the deformed dinucleus. The small quantal dispersion Δl = (10.3 ± 0.1)ħ of the entrance channel angular momentum, determined by analysing the dissipative fragment angular distribution in the framework of the Strutinsky model, is suggested to limit the broadening of the preequilibrium GDR width.

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.

The β decay of 94Pd and of the 71s isomer of 94Rh was investigated by using total γ-ray absorption techniques. Several levels in 94Rh are established, including a new low-lying isomer characterized by a half-life of 0.48(3)μs and a de-exciting transition of 55keV. E2 multipolarity is determined for this transition by measuring the intensities of its γ-rays and the characteristic X-rays from its electron conversion. On the basis of the measured reduced β-decay transition rates to known 94Ru levels and shell model considerations, the spin-parity of the 71s and the 0.48μs isomers of 94Rh is assigned to be (4+) and (2+), respectively. The β-decay strength distributions measured for 94Pd and the 71s isomer of 94Rh yield Q EC values of 6700(320) and 9750(320)keV for these decays and give evidence for the population of those states below and above the magic N = 50 gap that belong to both components of the 0g spin-orbit doublet.

The β-decay of 105Sn was re-investigated at the ISOL facility of GSI Darmstadt by using a total absorption spectrometer. The experimental results include the half-life and β-delayed proton branching ratio of 32.7(5)s and 1.1(4) . 10-4, respectively, and the contribution of electron capture to the 105Sn decay of 0.420(35). The Gamow-Teller strength distribution peaking at 3.6MeV was measured, yielding a summed Gamow-Teller strength of 3.0(4). The latter data are discussed in comparison with shell-model predictions based on an empirical interaction.

A new measurement of the cross section of 7Be(p, $ \gamma$ )8B will be done in inverted kinematics with the recoil separator ERNA at the CIRCE laboratory in Caserta, Italy. The 8B recoils will be produced in a windowless hydrogen gas target. We report here on the construction and characterization of the gas cell. In detail we describe measurements for target density, the profile determination via the 7Li(p, p’)7Li* reaction as well as the role and performance of a gaseous post-stripper.

The quasi-elastic scattering angular distribution of the proton drip line nucleus F-17 on a C-12 target was measured at 60 MeV. The experimental data have been compared with the theoretical analysis based onto optical model and continuum discretized coupled channels (CDCC). The couplings between breakup and elastic scattering channels, and between inelastic and elastic scattering channels resulted very weak. In order to explore the breakup effects the total reaction cross-section was deduced from the angular distribution of the quasi-elastic scattering data, and then compared with the existing data for the other weakly and tightly bound nuclei on C-12 target using a universal function. From this comparison, we concluded that the breakup effect is not important for weakly bound projectiles on the light target as obtained also with the CDCC analysis.

The existence of the dynamical dipole mode in the 192Pb composite system was investigated, through the study of its prompt γ decay, employing the 40Ca+152Sm and 48Ca+144Sm reactions at Elab=11 and 10.1 MeV/nucleon, respectively. The γ-rays and light charged particles were detected in coincidence with evaporation residues and fission fragments. First results of this experiment show that the dynamical dipole mode survives in collisions involving heavier mass reaction partners than those studied previously. As a fast cooling mechanism on the fusion path, the prompt dipole γ radiation could be of interest for the synthesis of super-heavy elements through "hot" fusion reactions. Furthermore, by using radioactive beams and the prompt γ radiation as a probe we could get information on the symmetry energy at sub-saturation densities.

A low threshold charged particle three-stage detector has been designed, built and successfully tested. A truncated pyramidal geometry has been chosen to use the device as an element in a large solid angle array for heavy ion nuclear experiments. Angular resolution of 0.4° at 35 cm from the target, energy resolution of about 1% for the elastically scattered ions and Z resolving power of 63 for Z = 17 have been achieved in the 35 Cl+ 64 Ni reaction at 280 MeV incident energy.

We have studied the elastic scattering of the exotic 17 F nuclei from 208 Pb at Coulomb barrier energies. For the measurement we used a new detector array with pixel structure and a large solid angle. Optical potential analysis shows that 17 F has an imaginary potential much less deep than 19 F. Information on the exclusive 17 F breakup cross section has been deduced too.