The rms beam envelope oscillations, risen from the mismatching of high intensity beams propagating along periodic focusing cells, can induce a halo formation. In some case, a very fast oscillation ...damping, due in all probability to a Landau mechanism of stabilization, can occur minimizing the halo extent generated. In this paper the possibility of using this fast damping to contain the halo formation on the beam during the transportation along periodic focusing cells will be explored and discussed.
Recent results in accelerator physics have shown the feasibility of a coupling scheme between a cyclotron and a linac for proton acceleration. Cyclotrons with energies up to 30 MeV, mainly devoted to ...radioisotopes production, are available in a large number of medical centres. These two evidences have suggested the idea to study and design a linac booster able to increase the initial proton energy up to the values required for the treatment of tumors, like the ocular ones. One of the main challenges in such a project is related to meet the requirement of having sufficient mean current for therapy from a given injection current coming from the cyclotron. In this paper we will review the rationale of the project in order to optimize the transmittance and to minimize the duty-cycle. In this frame we will discuss the basic design of a compact 3GHz linac, from 30 to 62 MeV, with a new approach to the cavities used in a SCL (Side Coupled Linac) structure (PALME project).
In order to have efficient particle acceleration it is fundamental that the particles experience, in the accelerating gap, field amplitudes as uniform and as high as possible from gap to gap. Because ...of the unavoidable fabrication errors, an accelerating structure, when assembled, exhibits field values lower than the nominal ones and/or not uniform. All the usual procedures developed in order to adjust the parameter deviations responsible of the malfunctioning of these structures, are based on field amplitude measurements, by using the bead pull technique, which is a very invasive technique. In this paper the philosophy is reversed: it is assumed that all the information can be got by Sounding the Modes of the whole System (SMS) and correct the deviation of each frequency mode from its nominal value by means of an appropriate tuning of the cavities: resorting to a perturbative technique applied to a circuit model representing this kind of structures, it is possible to calculate the amount of tuning to give to the cavities. It will be shown that a very good equalization and maximization of the fields in the cavities can be achieved by using this technique.
Simulation of a laser diagnostics for detection of ordered structures in an ion beam is shown with reference to presently operating or under design storage rings in which laser cooling is ...implemented. The diagnostics, however, could potentially be extended to any storage ring. The method is capable to firmly resolve ordering of an ion string with currently available technology in a non-destructive way. Information concerning short-range correlation can be also inferred for very cold but not crystalline ion beams – a condition that is more likely to be reached in presently operating storage rings.
The "charge state breeder" BRIC (BReeding Ion Charge) is based on an EBIS source and it is designed to accept Radioactive Ion Beam (RIB) with charge +1, in a slow injection mode, to increase their ...charge state up to +n. BRIC has been developed at the INFN section of Bari (Italy) during these last 3 years with very limited funds. Now, it has been assembled at the LNL (Italy) where are in progress the first tests as stand alone source. The new feature of BRIC, with respect to the classical EBIS, is given by the insertion, in the ion drift chamber, of a Radio Frequency (RF) Quadrupole aiming to filtering the unwanted elements and then making a more efficient containment of the wanted ions. In this contribution, the measurements of the selective effect on the ion charge state containement of the RF quadrupole field, applied on the ion chamber, will be reported and discussed. The ion charge state analisys of the ions trapped in BRIC seem confirm, as foreseen by simulation results carried out previously, that the selective containment can be obtained. A modification of the collector part to improve the ion extraction of BRIC will be also presented and shortly discussed.
The possibility of generating crystallized ion beams has always excited the interest of most people working on particle accelerators. The reason of this interest has manifold aspects: either a ...knowledge on a completely new research field or some of the applicative potentialities, connected with crystalline beams, would justify a careful investigation on this content.
The Conceptual Design of a low-energy heavy-ion storage ring, called CRYSTAL, proposed for the experimental demonstration of crystalline beams at Legnaro Laboratories is presented.
Besides the study of crystalline beams the CRYSTAL Storage Ring (CSR) offers a large potential for fundamental research in nuclear, atomic and molecular physics. In this sense, the development of a second generation cooler ring with better lattice will give large possibilities to investigate more deeply in fundamental Physics.
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