Charge breeder electron cyclotron resonance ion sources (CB-ECRIS) are used as 1+ →n+ charge multiplication devices of post-accelerated radioactive ion beams. The charge breeding process involves thermalization of the injected 1+ ions with the plasma ions in ionion collisions, subsequent ionization by electron impact and extraction of the n+ ions. Charge breeding experiments of 85 Rb and 133 Cs ion beams with the 14.5 GHz PHOENIX CB-ECRIS operating with oxygen gas demonstrate the plasma diagnostics capabilities of the 1+ injection method. Two populations can be distinguished in the m/q-spectrum of the extracted ion beams, the low (1+ and 2+) charge states representing the uncaptured fraction of the incident 1+ ion beam and the high charge states that have been captured in ion-ion collisions and subsequently charge bred through electron impact ionization. Identification of the uncaptured fraction of the 1+ ions allows estimating the lower limit of ion-ion collision frequency of various charge states in the ECRIS plasma. The collision frequencies of highly charged ions (∼10 7 Hz) are shown to exceed their gyrofrequencies (∼10 6 Hz) at least by an order of magnitude, which implies that the dynamics of high charge state ions are dictated by magnetically confined electrons and ambipolar diffusion and only low charge state ions can be considered magnetized. Furthermore, it is concluded that the plasma density of the ECRIS charge breeder is most likely on the order of 10 11 cm −3 i.e. well below the critical density for 14.5 GHz microwaves.
Clusters of fullerenes (C60,C70)(n) are produced in a gas aggregation source and are multiply ionized in collisions with highly charged Xe(20+,30+) ions. Their stabilities and decay processes are analyzed with high-resolution time-of-flight mass spectrometry. Fullerene clusters in charge states up to q=5 have been observed and appearance sizes are found to be as small as n(app)=5, 10, 21, and 33 for q=2, 3, 4, and 5, respectively. The analysis of the multicoincident fragmentation spectra indicates a high charge mobility. This is in contrast to charge localization effects which have been reported for Ar(q+)(n) rare gas clusters. Clusters of fullerenes are found to be conducting when multiply charged.
C60(2-) and C70(2-) dianions have been produced by electrospray of the monoanions and subsequent electron pickup in a Na vapor cell. The dianions were stored in an electrostatic ring and their decay by electron emission was measured up to 1 s after injection. While C70(2-) ions are stable on this time scale, except for a small fraction of the ions which have been excited by gas collisions, most of the C60(2-) ions decay on a millisecond time scale, with a lifetime depending strongly on their internal temperature. The results can be modeled as decay by electron tunneling through a Coulomb barrier, mainly from thermally populated triplet states about 120 meV above a singlet ground state. At times longer than about 100 ms, the absorption of blackbody radiation plays an important role for the decay of initially cold ions. The tunneling rates obtained from the modeling, combined with WKB estimates of the barrier penetration, give a ground-state energy 200+/-30 meV above the energy of the monoanion plus a free electron and a ground-state lifetime of the order of 20 s.
The ground state of the proton-rich, unbound nucleus 11N was observed, together with six excited states using the multinucleon transfer reaction 10B(14N,13B)11N at 30A MeV incident energy at Grand Accelerateur National d'Ions Lourds. Levels of 11N are observed as well defined resonances in the spectrum of the 13B ejectiles. They are localized at 1.63(5), 2.16(5), 3.06(8), 3.61(5), 4.33(5), 5.98(10), and 6.54(10) MeV above the 10C+p threshold. The ground-state resonance has a mass excess of 24.618(50) MeV; the experimental width is smaller than theoretical predictions.
We report the case of a patient who had 2 rare diseases, annular atrophic lichen planus (AALP) and Sneddon’s syndrome (SNS). This patient had also digital nodules with histological abnormalities suggestive of SNS vasculopathy, which have not been reported so far. AALP is the most rare of all varieties of lichen planus since this case is the third reported to date. The association of livedo racemosa and cerebrovascular disease is the hallmark of SNS, the incidence of which is estimated to be 4 cases per year per million inhabitants. In both diseases, an abnormal production of elastic-tissue-degrading enzymes or a constitutional abnormality of the elastic tissue can be postulated, since SNS is characterized by arteriolar changes with deterioration of the internal elastic lamina and AALP by destruction of the dermal elastic tissue.
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