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The28Si+64Ni reaction at 163.8 MeV incident energy is studied by measuring in coincidenceγ-rays and charged particles identified from Z=2 to Z=16. The transition from quasi-elastic to more damped reactions is observed when the difference between the detected charge and the projectile one is increased. The strong influence of the particle decay on the measuredγ-ray multiplicity is evidenced with the help of the statistical model computer code CASCADE. Dissipative events are well described in the rolling limit with excitation energy equally shared between the fragments. The overall agreement is lost for the fragments with the projectile charge which show a small value of theγ-multiplicity even for dissipative events. This is probably connected with the previously observed non statistical behavior of gamma rays emitted in coincidence with projectile-like fragments. In the alpha-spectrum measured in coincidence with gamma-rays, the deexcitation of fused systems is clearly separated from in flight emission of deep inelastic fragments. The low measured gamma-ray multiplicity for fusion events is qualitatively explained taking into account the effect of alpha-emission in the statistical decay.

For an improved determination of the 7Be(p, γ)8B absolute cross section, the reaction is studied in inverse kinematics. The study involves a 7Be radioactive ion beam of 8.0 MeV, a windowless H2 gas target, and an efficient recoil separator for the detection of the 8B residual nuclides. The techniques used to produce such a beam as well as the first direct observation of 8B are reported.

A new pixel-structure detector array with a large solid angle coverage has been used for the first time to study the elastic scattering of exotic $^{17}\mathrm{F}$ nuclei from a $^{208}\mathrm{Pb}$ target at $90.4\phantom{\rule{0.3em}{0ex}}\mathrm{MeV}$. The experimental data have been analyzed in the framework of the optical model potential and the real and imaginary strong absorption radii have been evaluated. These quantities have been compared with those obtained for the system $^{19}\mathrm{F}+^{208}\mathrm{Pb}$ at the same energy in the center of mass frame. The $^{17}\mathrm{F}+^{208}\mathrm{Pb}$ reaction cross section is more similar to those of the systems $^{16,17}\mathrm{O}+^{208}\mathrm{Pb}$ rather than to the one of the system $^{19}\mathrm{F}+^{208}\mathrm{Pb}$ at similar energies: this indicates that in the energy range around the Coulomb barrier the breakup channel is still weak. The exclusive breakup cross section $^{17}\mathrm{F}\ensuremath{\rightarrow}^{16}\mathrm{O}+p$ has been measured for the first time at energy below the Coulomb barrier.

The aim of this study was to verify in bruxism patients the possible efficacy of auricular stimulation in reducing the hypertonicity of some masticatory muscles.Forty-three bruxism patients were randomly allocated to 3 groups: acupuncture, needle contact for 10 seconds, no treatment (control). Helkimo's clinical dysfunction index (CDI) and anamnestic dysfunction index (ADI) were used to assess the functional state of the masticatory system. The resting electrical activity of the anterior temporalis (AT), masseter (MM), digastric (DA) and sternocleidomastoid (SCM) muscles was measured, according to Jankelson, with surface electrodes at baseline, after stimulation and continually for 30 minutes (120 measurements in total). The electromyographical variations in the 3 groups were studied with t test for independent samples.Acupuncture and needle contact were superior to control in reducing the muscle hypertonicity of all muscles except SCM. In the comparison between acupuncture and needle contact the former showed better results only for the right TA and left DA (p = 0.000).In this study it was possible to measure the efficacy of the stimulation of only one point or area, which is an ideal model for research in acupuncture. The auricular area we chose for stimulation was never used before for the purpose of relaxing masticatory muscles. Acupuncture and needle contact for 10 seconds showed similar effects.

The decays of the neutron deficient nuclei 94,95Ag, 100,102In and 102Sn were investigated at the GSI on‐line mass separator. The Gamow‐Teller decay of 100,102In and 102Sn was studied by using an array of germanium detectors and a total absorption spectrometer. In 94Ag and 95Ag, spin‐gap isomers were identified and their decays were investigated. Results obtained in these studies are discussed and compared to predictions of shell model calculations.

The prompt γ radiation originating from the dynamical dipole mode decay was investigated in the 192Pb composite system employing the 40Ca + 152Sm and 48Ca + 144Sm reactions at Elab=11 and 10.1 MeV/nucleon, respectively. The γ-ray energy spectra at various polar angles were obtained for fusion-evaporation and fission events by detecting the high energy γ rays with the MEDEA experimental apparatus in coincidence with evaporation residues and fission fragments. Preliminary 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.

We report on the results obtained from the study of the 32S + 64Ni and 32S + 58Ni peripheral reactions at incident energies E lab = 288 MeV and E lab = 320 MeV, respectively. High-energy γ-rays were detected in an array of 8 seven-pack BaF2 clusters. Coincidence with complex fragments detected in 12 three-stage telescopes ensured the selection of peripheral reaction events. All of the relevant reaction parameters were kept constant with the exception of the different initial dipole moment caused by the different entrance channel charge asymmetry. While for quasi-elastic events no N/Z effect was observed in the differential γ-ray multiplicities of the two reactions, for deep-inelastic events a larger dipole γ-ray emission occurs during the more N/Z asymmetric reaction. A theoretical interpretation based on a collective Bremsstrahlung analysis of the reaction dynamics is presented.

Precise elastic scattering measurement were done at the Coulomb barrier for the system 9 Be+ 209 Bi from 40 to 48 MeV in 2 MeV intervals and 3.5° steps. The deduced Woods–Saxon potential shows a very unusual behaviour that could be connected to the breakup of the weakly bound projectile expected to have a large cross section. The same potential also reproduces the observed inelastic scattering.

We measured for the first time 7 Be elastically scattered nuclei as well as 3,4 He reaction products from a 58 Ni target at 22.3 MeV beam energy. The data were analyzed within the optical model formalism to extract the total reaction cross section. Extensive kinematical, Distorted Wave Born Approximation (DWBA) and Continuum Discretized Coupled Channel (CDCC) calculations were performed to investigate the 3,4 He originating mechanisms and the interplay between different reaction channels.

Il programma AirWatch riguarda l'osservazione dallo spazio degli sciami estesi di particelle prodotti nell'atmosfera da particelle cosmiche di altissima energia. Nell'ambito di tale programma si colloca il progetto EUSO, recentemente sottoposto all'ESA da una collaborazione internazionale. In questa nota si descrivono la problematica scientifica connessa con i raggi cosmici di altissima energia, le problematiche tecniche legate all'osservazione dallo spazio degli sciami atmosferici estesi e si descrivono le linee di una possibile partecipazione dell'INFN al programma AirWatch ed al progetto EUSO in particolare.

The cross sections for elastic scattering of the weakly bound ${}^{9}\mathrm{Be}$ on ${}^{209}\mathrm{Bi}$ around the Coulomb barrier have been measured with $\ensuremath{\sim}5%$ absolute accuracy from 40 to 48 MeV. The potential obtained from an optical model analysis has an unusual behavior. At the strong absorption radius the imaginary (absorptive) potential is increasing (rather than decreasing) with decreasing energy, as would be consistent with a long range polarization potential arising mainly from couplings to breakup channels. The real part, on the other hand, displays a strong attractive polarization contribution with the maximum at the barrier, as would be normally expected from a polarization contribution arising from strong couplings. The inelastic multiplet in ${}^{209}\mathrm{Bi}$ of collective nature around 2.6 MeV, originating from the coupling ${[}^{208}\mathrm{Pb}{(3}^{\ensuremath{-}})\ensuremath{\bigotimes}{h}_{{9/2}^{\ensuremath{-}}}{]}_{{J}^{\ensuremath{\pi}}},$ was seen only at 48 MeV. The total multiplet cross section is well reproduced by coupled channel calculations with the potential obtained from the optical analysis and the experimental $B(E3)$ strengths of the ${}^{209}\mathrm{Bi}$ multiplet levels.

Nuclear fusion reactions play a key role in the understanding of energy production, neutrino emission and nucleosynthesis of the elements in stars. The direct measurement of the cross section of these reactions at the relevant energies is usually hampered by cosmic radiation, beam induced background and/or the radioactivity of the nuclei involved. In order to suppress these background contributions one can either place an experiment underground [1,2] or exploit coincedence techniques between the reaction products. The major aspect in this contribution is the efficient detection of the recoil nucleus in a direct capture reaction.

Nuclear fusion reactions play a key role in the understanding of energy production, neutrino emission and nucleosynthesis of the elements in stars. The direct measurement of the cross section of these reactions at the relevant energies is usually hampered by cosmic radiation, beam induced background and/or the radioactivity of the nuclei involved. The measurements are expected to be completed by fall 1996.

γ-rays are measured in coincidence with the dissipative complex fragments from the35Cl +64Ni reaction at 7.7 A MeV. Theoretical γ-ray coincidence spectra are determined through a fitting procedure using the contribution of the excited fragment statistical γ-decay calculated by means of the CASCADE code. Whereas the expected statistical spectra fit very well the data in the energy regionE ν=2 to 8 MeV, above this energy another emission mechanism in addition to the statistical decay has to be considered in order to reproduce the experimental spectra. Simulations based on the Vlasov equation suggest that this emission could come from the decay of dipole strength excited in the intermediate dinuclear system.

It is shown that the Partially Overlapping Molecular Level Model (POMLM) accounts for the experimental results of the dissipative28Si +48Ti collision around 210 MeV incident energy. The general trend of the properties of the fluctuations as well as the average angular distributions are reproduced by the same set of main parameters. A general consistency is also found between the present data and the data obtained in previous work on the same colliding system performed at lower incident energy (around 123 MeV).

Angular distributions of fragments emitted in the reaction {sup 19}F+{sup 63}Cu measured in the range {theta}{sub lab}=10{degree} to 120{degree} at incident energy between 100 to 108 MeV (lab) have been analyzed according to available models for deep inelastic collisions with the aim to evidence different mechanisms contributing to such reactions. The analysis was performed in the framework of Strutinsky model taking into account both the development of Kun and of Abul-Magd and Simbel. To determine the interaction times, previously published excitation functions were also analyzed in the framework of Kun's model of cross section statistical fluctuations and near-side and far-side scattering were taken into account separately. It was pointed out that the rotational energy dissipation occurs in a limited angular range around the grazing angle. The presence of two distinct reaction mechanisms, each of them characterized by an interaction time, was also evidenced by comparing the energy averaged angular distributions to the Abul-Magd and Simbel model for dissipative collisions.

Photons emitted in the28Si+64Ni and32S+64Ni reactions at 143 MeV and 156 MeV incident energy respectively, have been detected in coincidence with the ejected charged fragments. An array of 48 BaF2γ-rays detector and 6 solid state silicon detector telescopes have been used. Photon energy spectra measured in the energy range from 2 to 20 MeV in coincidence with ejectiles coming from deep inelastic reactions, are consistent with statistical emission from the reaction products.

A case of alopecia areata and homolateral headache due to an impacted superior wisdom tooth is reported. After the extraction, the headache disappeared, hair regrew in the alopecic area and in 4 months completely covered the whole area.

A new experimental apparatus for charged particle detection, named EXODET (EXOtic DETector) has been designed to be used in nuclear physics experiments involving radioactive ion beams (RIBs). A typical feature of RIBs presently available at the first-generation production facilities is the low beam intensity (10/sup 5/--10/sup 6/ pps); therefore, a large solid angle coverage and a high granularity are required to allow the reconstruction of the complete event kinematics. In this paper, we present the main features of the EXODET apparatus, fulfilling the previous requirements, and the first experimental results.

In the present contribution, we will briefly present an overview of the last experimental results obtained by the Italian EXOTIC collaboration on the study of the reaction mechanisms around the Coulomb barrier with light weakly bound Radioactive Ion Beams. Several experiments have been performed by our group in different laboratories: at ANL (USA) and, more recently, at LNL (Italy) to study the system 17F+208Pb and at RIKEN (Japan) for the system 11Be+209Bi. A comparative discussion with the results obtained for other reactions induced by light weakly‐ and tightly‐bound projectiles will be finally given.

We report on the results obtained from the study of the 32S +74Ge deep inelastic reaction at incident energy E= 320 MeV. High-energy γ-rays were detected in an array of 6 seven-pack BaF2 clusters. Coincidence with complex fragments detected in 12 three-stage telescopes ensured the selection of peripheral reaction events. In order to investigate the pre-equilibrium dipole strength excitation two independent analyses were performed. In the first analysis the energy spectra of the γ-rays were evaluated in the statistical model framework while in the second one the γ-ray fragment angular correlation with respect to the nuclear spin vector of the composite system was studied. Both methods indicate the excitation of dipole strength in the highly deformed dinucleus and provide dipole resonance parameter sets that are in good agreement with each other.

Chlorophyll plays a fundamental role in the photosynthetic process of living plants, it is therefore obvious that each phenomenon related to chlorophyll may also be related to the photosynthetic process. Since chlorophyll a shows a strong fluorescence emission in the wavelength region between 67 0 nm and 740 nm it is attractive to analyze the potential of laser fluorosensors in the remote sensing of living plants. While a quite large number of papers were devoted to the lidar remote sensing of chlorophyll fluorescence in phytoplancton only few papers has been devoted to the remote sensing of chlorophyll fluorescence in living plants. A research program in this field was started as a part of a national program on agriculture improvement (IPRA Project), the analysis was carried out in the laboratory by means of a lidar simulator and in fields by means of the lidar fluorosensor FLIDAR-2.

The diagonal ear-lobe crease, detectable especially after the age of 40, is still accepted as a sign of coronary heart disease risk. In the literature some authors report an association between anxiety and coronary heart disease. In our work a group of 143 patients with ear-lobe crease showed - in both sexes and in all examined decades (5th, 6th, 7th) - higher levels of anxiety than in the control group. The possible significance of the crease has been considered on the grounds of present knowledge of ear-acupuncture and the somatotopic mapping of CNS on the ear-lobe.

With this preliminary note the Authors propose a study of morphological changes and discolorations of the skin of the auricle in correlation with a chronic pathology. They present an extensive report of 13 patients with a long-standing symptomatology between 3 and 20 years. Time factor and the laterality problems are discussed.

The relationships between wisdom tooth and headache have been rarely studied. The aim of this paper was to follow 13 patients, which suffered with idiopathic headache, after extraction of impacted maxillary wisdom tooth. The authors separated in two group the patients on the basis of a different anatomic site of pain. Patients with bilateral headache or monolateral headache without preferable anatomic site did not respond positively to the extractions. On the other hand the group of patients with monolateral headache or bilateral headache with preferable anatomic site obtained an improvement after the extraction of the maxillary homolateral wisdom tooth.