SNEAP 2012

30 set 2012, 17:30 → 5 ott 2012, 14:30 Europe/Rome

Sala Villi (INFN Laboratori Nazionali di Legnaro)

Symposium for North Eastern Accelerator Personnel

SNEAP is a community of personnel involved with particle accelerators, mainly electrostatic, and their use.

Founded in 1968, the organization gathers annually to discuss and exchange information to the benefit of all those who attend. The goal of the Symposium is to have a workshop of operation personnel discussing and sharing experiences in order to help each other in solving the practical problems and let their ingenuities became common knowledge of the community.

The topics covered include ion sources, electrostatic and rf accelerators, telemetry and control systems, cryogenic systems, safety issues and many other topics relevant to the operation of small to medium sized accelerator laboratories.

The meeting format is made of oral presentation and poster stands followed by open and informal discussions concerning laboratory reports and contributed papers .

Space for vendors is made available to permit attendees to speak directly with manufacturers and their representatives and to inspect many new devices and products.

Attendees include representatives from Universities, National Laboratories, and Industrial Research Laboratories from the United States of America. and many other countries including Argentina, Australia, Canada, China, Croatia, Finland, France, Germany, India, Italy, Japan, South Africa, Spain, Switzerland and others.

Final Circular SNEAP12_Final_Circular.pdf

First Circular SNEAP12_First_Circular_14feb2012_final_AL-4.pdf

domenica 30 settembre

17:30 Registration

18:30 Welcome Reception

lunedì 1 ottobre

08:30 Registration

Opening

1 Welcome Address

10:30 Coffee Break

Physics at low medium energy

2 The European Collaboration for Stable Ion Beams - ECOS

In the past a sufficiently large number of facilities have been available to the European Nuclear Physics Community delivering stable heavy ion beams at energies close to the Coulomb barrier. Many of these facilities are being recognized as leading European Research Infrastructures. Nevertheless, the last decade has seen the phasing out of several of these facilities in Europe resulting in the consequence that the beam time available to the European Nuclear Physics community has become marginal. In the meantime new physics domains have emerged that require the use of higher beam intensities than available today. NuPECC has been concerned by this issue and has stressed on many occasions and particularly in its recommendations for the last Long Range Plan, the importance of the existing stable beams facilities for our field. The other important action taken by NuPECC has been to appoint the ECOS working group in order to examine the research perspectives with high intensity stable ion beams, to help categorize existing facilities and their possible up-grades and to identify the opportunities for a dedicated new facility in Europe. In my talk I will try to show that many nuclear physics questions can be better (or perhaps only) addressed with high intensity stable beams at energies close to the Coulomb barrier and will as well present the ECOS working group conclusions and recommendations.

Relatore: Dr. Faical Azaiez (L'institut de Physique Nucléaire d'Orsay)

Slides SNEAP-2012-ECOS.pdf

3 Medium-High Energy nuclear Physics at LNL

The main research activity at LNL is based on the use of the Tandem-ALPI-PIAVE accelerator complex for production and acceleration of heavy ions. Beam time from this accelerator complex is mainly dedicated to basic nuclear physics research but an important fraction of the beam time is also allocated for applied and interdisciplinary physics measurements. The large variety of ion beams delivered by the powerful combination of electrostatic and superconducting RF accelerators, with a broad range of energies, allows for the exploration of the most intimate aspects of the nuclear structure. Nuclear structure and reaction mechanisms at energies close to the Coulomb barrier are studied with dedicated instruments developed at LNL. The development of acceleration techniques and of the instruments for the nuclear physics research made of the Laboratori Nazionali di Legnaro one of the most prominent nuclear physics center in the world. An overview of the research activities performed with the Tandem-ALPI-PIAVE accelerator complex will be given.

Relatore: Dr. Calin A. Ur (INFN Padova)

Slides CAUr-SNEAP.pdf

4 Interdisciplinary Physics with Small Accelerators at LNL: status and perspectives

The Laboratori Nazionali di Legnaro have a long lasting tradition on the use of light MeV ion beams in interdisciplinary research. The AN2000 (2.2MV) and the CN(6.1MV) Van de Graaff accelerators are today almost entirely dedicated to interdisciplinary studies, by providing about 3000 beam time hours/year to internal and external users with active projects in Materials Science, Surface Modification, Radiation Interaction and Damage, Ion Beam Analysis and Channeling, Environmental Sciences, Radiation Biophysics and Medicine, (Micro and nano)Dosimetry, Art and Archaeology. On the average, about 40 experiments are approved yearly by the User Selection Panel. The two Ion Beams Facilities are versatile and complementary. They provide light ion beams with terminal voltages between 0.3 to 6.1 MV in a wide range of intensities ranging from precision ultra-low intensity (single particle) micro-beams to more intense beams for surface irradiation, ion beam writing and MeV neutrons production from deuteron and proton irradiated Be and Li-based targets. A plurality of ion-surface interaction schemes including forward and backscattering and ion channelling geometries are successfully implemented in collaboration with the end-users. An overview of the status and perspectives of the two accelerators and related activity will be given.

Relatore: Dr. Valentino Rigato (INFN Legnaro)

Slides SNEAP12-Rigato.pdf

5 SPES

SPES (Selective Production of Exotic Species) is an INFN project to develop a Radioactive Ion Beam (RIB) facility based on the ISOL techniqueas an intermediate step toward the European ISOL facility EURISOL. SPES is under construction at the LaboratoriNazionali di Legnaro. The main goal is to provide an accelerator system to perform forefront research in nuclear physics by studying nuclei far from stability. A H- proton cyclotron will be used as driver for the ISOL target. The exotic beams will be selected and injected in the ALPI superconductive linac to produce reaccelerated RIB’s at energy as high as 10 AMeV at A=130. An interdisciplinary research centerwill be also developed, taking advantage of the cyclotron configuration allowing the production of two independent proton beams. The SPES acceleration system will be presented, together with the statusof the facility construction.

Relatore: Dr. Gianfranco Prete (INFN Legnaro)

Slides 121001_gp_Prete_SPES_SNEAP_1.pdf

13:00 Lunch

Laboratory Report 1

6 The Munich MP-Tandem Status

The MP-Tandem accelerator of the Maier-Leibnitz-Laboratorium (MLL), the former „Beschleunigerlabor der LMU und TU München“ was running very reliable during the last years. The accelerator was running 7000 hours for experiments in the fields of nuclear and applied physics. The status of the Tandem accelerator will be presented and some technical problems of the past years of operation.

Relatore: Dr. Ludwig Beck (Maier-Leibnitz-Laboratorium / Beschleunigerlabor)

Slides BeckPresentationSneap2012.pdf

7 Refurbishment of the Electrostatic Accelerators of iThemba LABS

The two electrostatic accelerators in operation at iThemba LABS are a 6 MV CN Van de Graaff accelerator dating back to 1962 and a 6 MV EN Tandem accelerator dating back to 1971. The reliability of the CN Van de Graaff has become a major problem and a decision was made to embark on a refurbishment of the accelerator. To refurbish a 50 year old accelerator while still maintaining a research program is a difficult task. Some of the topics that will be discussed are, amongst others, improvements to components with poor reliability statistics; digital monitoring of all the components in the terminal; implementation of a safety interlock system to monitor all aspects of the accelerator; much improved beam diagnostics; converting the vacuum system to computer control at minimum cost and remote computer control of the terminal potential stabilizer system. About 90% of all of the control elements have been moved over to the open source EPICS platform running on Linux. At present the project is nearing completion and the benefits of the refurbishment are well evident in the much improved reliability statistics of the accelerator, as well as the positive feedback from the users. A decision was made to refurbish and upgrade the 6 MV EN Tandem accelerator so that it can also be used for accelerator mass spectrometry. This project is also in an advanced stage and we hope to complete the project by the end of 2014. Some of the technical challenges relating to this project will also be discussed.

Relatore: Dr. JL Conradie (iThemba LABS)

Slides SNEAP_presentation_01_10_2012_JL_Conradie.pdf

8 Nuclear Synthesis On Ordered Crystal Target With Participation Of Monochromatic Beams Of Light Or Middle Isotopes

In ordered crystal lattice very strong influence of crystal axes and planes electrical field on motion and interaction of fast charged particles with crystal atoms and nuclei exists. In works [1,2] it was shown that in monocrystal targets like possibility of fusion process with the participation of both target nuclei (e.g. ) and beam of fast nuclei (e.g. ), directed at Lindhard angle, increases by 10-100 times relative to the possibility of alternative process of deceleration on atomic electrons. Such changes are based on the usage of specific channeling physics regime of motion - "overbarrier motion". At such regime the processes of spatial redistribution and dechanneling of accelerated ions take place. In the report the methods of optimization and practical realization of such nuclear fusion are discussed in details. The additional method of radical optimization of fusion processes with the participation of monochromatic beams of middle mass isotopes is proposed. It is well known that the presence of the Coulomb barrier is the main obstacle to performing nuclear reactions of synthesis with low energy of interacting nuclei. In order to make such reaction possible, it is necessary to place interacting particles in the same spot simultaneously (within the range of atomic force action). In this case, the cross section of nuclear reaction depends on the energy of reciprocal movement of nuclei and matches the “internal atomic cross section” . The features of optimized nuclear fusion model, with the use of accelerated average-mass ions beams and condensed-surface targets,

Relatore: Dr. Sergio Bartalucci (LNF)

Slides Bartalucci_LegnaroOct2012.pdf

15:30 Coffee Break

Laboratory Report 2

9 Tandem ALPI PIAVE complex.

Tandem ALPI PIAVE consists in an electrostatic 15MV XTU Tandem followed by a superconducting Linac. The linac can be also alternatively fed by PIAVE, a positive ion injector. The beam can be delivered to three experimental rooms. The complex works 24 hours per day and 7 day per week and the reliability of the different systems is fundamental to guarantee beam on target in all the scheduled periods. This contribution illustrates the improvements recently performed to increase the overall reliability of the accelerators. In particular the new system of managing-control of the magnets and their power supplies, will be described.

Relatore: Dr. Davide Carlucci (INFN-LNL)

Slides Tandem_ALPI_PIAVE_complex_D._Carlucci_SNEAP_2012_Oct_1st,_2012_Last_release.pdf

10 LNL Low Energy accelerators

At the Laboratori Nazionali di Legnaro there are two electrostatic accelerators that made the history of the nuclear physic research and are still in operation giving a good service to the user comminity. Theese are the CN machine and the AN2000. The CN was the first accelerator installed at the LNL and the maximum terminal voltage was 5.5 MV and it was upgraded to 7MV. It is a vertical machine signle stage with a capability of delinevy 3 MHz pulsed beam. The AN2000 is our material science tool. It is a 2 MV horizontal machine and its most significative capability is the microbeam line. In this contribution we will describe the two installations with all the capabilities of the machines in terms of beam species, beam quality and time structure.

Relatore: Dr. Augusto Lombardi (Laboratori Nazionali di Legnaro INFN)

Slides Lombardi_low_energy_legnaro_SNEAP12_.pdf

11 Status and Recent Upgrades of the Tandem Accelerator Facility at RBI Zagreb

Tandem accelerator facility at RBI Zagreb consists of two electrostatic accelerators (6 MV HVEC EN and 1 MV HVEE Tandetron) and eight beamlines. Despite the decrease in total beam time fraction dedicated to basic nuclear physics, the exploitation of the machines is increasing, mainly due to the expanding of accelerator and beam line capabilities of importance to applications in materials science. Several international technical projects in past years helped us to renew the facility and widen its capabilities. The most recent upgrades are installation of new sputtering ion souces on both accelerators and commissioning of dual beam irradiation scattering chamber. The status of the utilization of machines and beamlines as well as details of the upgrades carried out in past years will be presented. Also a brief overview of the main projects, physics performed and users distribution will be given. We will also present future plans in development of the whole facility.

Relatore: D. Španja (RBI Zagreb)

Slides Laboratory_for_Ion_Beam_Interactions_Damir.pdf

martedì 2 ottobre

Laboratory Report 3

12 Status report on the Accelerator Mass Spectrometry systems at the Woods Hole Oceanographic Institution

The National Ocean Sciences Accelerator Mass Spectrometry (NOSAMS) facility at the Woods Hole Oceanographic Institution operates two 14C AMS systems. The first system was purchased from the US-AMS Corporation and utilizes a 3 MV tandetron accelerator with a 59-sample sputter source. The second of these two systems is based around a 500 kV National Electrostatics Corporation Pelletron accelerator and incorporates both a 134-sample conventional graphite sputter source and a unique, gas-accepting, microwave ion source. Status and operational experiences with both accelerator systems will be presented.

Relatore: Dr. Mark Roberts (Woods Hole Oceanographic Institution)

13 Negative and Positive Ion beams and Sources at INFN-LNL

Negative ion beams have been produced and accelerated by the TANDEM electrostatic accelerator at LNL since 1980 for experiments in Nuclear Physic. The Ion Sources and the negative injector layout will be illustrated as well as the Ion types produced and used until now. From several years a positive ECR Ion Source for the positive injector PIAVE has been introduced and put into operation. A breaf illustration of the positive devices and beams will be also presented.

Relatore: Dr. Fabio Scarpa (Laboratori Nazionali di Legnaro INFN)

Slides Sneap12_FS.pdf

14 TAMIA, a Versatile Tool for Materials Analysis

The 5-MV belt-driven vertical tandem accelerator of Department of Physics of University of Helsinki has been in use for 30 years. A user/operator view of the various experiments done in the past and planned for the future are given.

Relatore: Dr. Pertti Tikkanen (University of Helsinki)

Slides TAMIAsneap2012.pdf

10:30 Coffee Break

Laboratory Report 4

15 Ion Accelerator at IUAC, New Delhi: Up-gradation and trouble shootings

Relatore: Dr. Sundeep Chopra (Inter University Accelerator Centre)

Slides SNEAP-2012_SundeepChopra.pdf

16 IFMIF

Soon will be available

Relatore: Dr. Andrea Pisent (INFN-LNL)

Slides pisent_IFMIF_SNEAP_2012_finale.pdf

17 Modernization of Control Systems for 5 MV Tandem Accelerator

Old but working Control equipment (about 30 racks) was dismantled and discarded due to complete renovation of accelerator building. An overview of the new control system is given to describe the architecture, the tools, and the components that have been used to build it. Examples of technical implementations are given.

Relatore: Sig. Harri Tyrväinen (Tapani)

Slides Sneap2012_1_Tyrväinen.pdf

18 Bayesian approach to accelerator control

The efficient use of accelerators requires highly optimized control and automation systems under the supervision of the human operator. The decisions that the operator makes in the brain are based on plausible reasoning which is intrisically Bayesian probability inference. A short introduction to inference under uncertain circumstances, together with potential applications in accelerator control are discussed.

Relatore: Dr. Pertti Tikkanen (University of Helsinki)

13:00 Lunch

LNL visit

mercoledì 3 ottobre

Technical Report 1

19 The Development of Vacuum System Engineering Guidelines at ANSTO

A recent review of the Australian Standards for pressure vessels revealed the lack of scrutiny on vacuum type pressure vessels. The standard has a category for vacuum vessels but it is open for mixed interpretation which has led to some safety concerns about the vacuum equipment used around the accelerators at ANSTO. The immediate response was to treat all vacuum equipment as pressure vessels and adopt a similar certification process as high pressure vessels. It was clear to accelerator staff that this was grossly unnecessary and that we must demonstrate why. This talk will discuss the work done in the accelerator area and the engineering department at ANSTO to develop a rational and safe approach to designing, manufacturing, certifying and operating vacuum equipment.

Relatore: Sig. David Garton (ANSTO)

Slides garton_Vacuum_System_Design_Constraints_at_ANSTO.pdf

20 New Radiation Safety System for 5 MV Tandem Accelerator

Old radiation safety system was dismantled and discarded due to complete renovation of accelerator building. Overview of the realization of the new Radiation Safety System and its components is given.

Relatore: Sig. Harri Tyrväinen (Tapani)

21 The Decompression of our 6MV EN Tandem Columns

This talk details our recent experience with the careful decompression and removal of our Tandem columns after locating and sorting various pieces of the original 1950’s equipment found scattered about in the attic. The people who did this job originally had long since gone, so there was a learning curve to go through.

Relatore: Sig. Chris Purcell (GNS Sciences)

Slides LOWER_HUTT_EN_Decompression_01.pdf

10:30 Coffee Break

Open Discussion

Problems? Solutions!

slides OpenDiscussion_Roehrich.pdf

22 Present Trends for Electrostatics Accelerators (Pelletrons)

Before 1980, the primary application for electrostatics accelerators was nuclear structure research. Then, only an accelerator providing analyzed beam was sold. It was up to the individual laboratory to provide all necessary analytical equipment for their specific application and experiments. Today, most accelerator systems are complete turn key systems with all necessary hardware and software for a wide variety of analysis applications. These include RBS, PIXE, ERD, NRA and AMS. As the number of individual applications increases, the overall demand has been increasing over the last five years. There is no single geographical location or application that is driving this demand. However, applications requiring an AMS configuration tend to be the most dominate. This talk will describe the various applications and machine configurations presently in manufacture.

Relatore: Dr. Greg Norton (National Electrostatics Corp.)

Slides Trends__G._Norton_SNEAP_2012.pdf

23 Installation, operational experience, beam purification techniques, and status report of the HIE-ISOLDE project.

REX-ISOLDE is the radioactive ion beam post-accelerator of ISOLDE. It employs a unique combination of Penning trap and Electron Beam Ion Source to charge-breed heavy ions before acceleration in a compact normal conducting linear accelerator to a maximum energy of 3 MeV/u. REX is in operation since 2001 and will be upgraded in the coming years with a superconducting quarter wave resonator linac (HIE-ISOLDE) to reach a final energy of 10 MeV/u for ion beams up to A/q 4.5. An overview of the installation will be given focussing on operational experience and beam purification techniques. A status report of the HIE-ISOLDE project will also be given.

Relatore: Dr. Didier Voulot (CERN)

Slides d_voulot__SNEAP12.pdf

13:00 Lunch

14:00 Excursion to Este and Montagnana

Departure at 14:30 from LNL

19:30 Social Dinner

Liviangior Restaurant

giovedì 4 ottobre

Technical Report 2

24 C&C Tandem

The Tandem of Orsay was installed in 1973 with a control-command system (C&C) which was manual and cabled on a central writing desk. In 1993, the installation of the ion source ORION in the 15 MV terminal imposed the development of a new system of C&C. In 1997, this system was gradually extended to the whole accelerator. Since 2008 many problems occurred because various components became obsolete. In addition, all the designers are retired. So we have decided to develop a new C&C based on automaton. In January, 2011 a first test has been successfully achieved with the installation of an automaton in the terminal of the accelerator. For the first time we have put an automaton in a very perturbing environment. Indeed the central electrode of the accelerator can be raised up to 15 MV. Such an intense field can be maintained only by strengthening the electric insulation with an efficient gas, the hexafluoride of sulfur (SF6) under 8 atm.

Relatore: Dr. Abdelhakim SAID (CNRS - Institute of nuclear physics of ORSAY)

Slides Présentation_SNEAP_2012__Siemens_final_pour_4_octobre_avion.pdf

25 MUNES project: status and perspectives of an RFQ based neutron facility in Italy

In the framework of MUNES (MUltidisciplinary NEutron Source) project, INFN is building an accelerator driven neutron source devoted to BNCT applications and to nuclear waste characterization. The source is based on three key components that were developed in the last few years at Legnaro National Laboratory (LNL): a high intensity proton injector, a high power Radio-Frequency Quadrupole (RFQ) and a high efficiency Beryllium converted. Accelerator status, recent RFQ high power test results and future plans will be presented.

Relatore: Dr. Enrico Fagotti (INFN-LNL)

Slides MUNES_E.Fagotti_sneap_12.pdf

26 Development of H- Ion Source for JYFL Pelletron Accelerator

A filament-powered multicusp ion source for production of H- has been developed for the JYFL Pelletron accelerator for the usage at the ion beam lithography and PIXE applications. The source can be considered conventional with the exception of the filter field being created with an electric magnet for continuous adjustability. A permanent magnet dipole-antidipole electron dump is integrated in the puller electrode. The two magnetic fields are separated by a magnetic SS430 plasma electrode insert. The source has been characterized with emittance and current measurements. It provides up to 50 μA of H- beam at 10 keV energy with 0.019 mm mrad 95 % normalized rms emittance through 2 mm aperture. Even lower emittance should be achievable by adjusting the plasma-electrode to puller-electrode gap distance as it has been noticed that the extraction geometry is not optimal for the typical lower currents required by the applications. The plasma electrode insert can be changed to a larger aperture one if higher current is required. The ion source extraction is capable of handling beam from 4 mm diameter aperture providing up to 200 uA of H-. If lower emittance is desired, the aperture can also be made smaller. The source design, measurements and extraction ion optics simulations are presented along with the costs related to this high brightness ion source project.

Relatore: Sig. Taneli Kalvas (University of Jyvaskyla)

Slides kalvas.pdf

10:30 Coffee Break

Technical Report 3

27 LHC Operation

With the LHC start up we had to learn how to operate powerful beams. The amount energy stored in LHC magnets and beams, and the potential damages produced by uncontrolled loss of this energy lead to the design of a very sophisticated interlock system. In addition the LHC is commissioned in steps of intensity and energy. We have to fulfill these vital tests before the nominal beams will collide at high energy. Sequencer, Safe machine parameters, Post-mortem, Collimators, Injection protection, Injection Quality Control, are the Software and Hardware tools that allow us to inject, ramp, squeeze and finally collide beams at 4 TeV. An overview of LHC operation and latest’s results will be presented.

Relatore: Rossano Giachino (CERN)

Slides RG_Sneap.pdf

28 Development of Ion Beam Related Research Around 1.7 MV Pelletron in Jyväskylä During Five Years of Operation

In late 2006 a fully functional 1.7 MV Pelletron tandem accelerator was donated to the University of Jyväskylä by the Technical Research Center of Finland. At that time the accelerator had only one RF ion source and one beamline for RBS. After an extensive development period over past five years, the facility now contains three ion sources and four beamlines. The two biggest changes inside the accelerator tank during the past 5 years has been the change of corona discharge based potential division to resistor based and a new turbo pumped stripper installation. Resistor based charge division change increased the terminal voltage stability and enabled the use of lower beam energies down to 150 keV. In 2012 the original terminal stripper was changed to one which has turbo pump based gas circulation. This stripper change has improved beam transmission and together with injector modification increased the maximum obtainable beam energy above 20 MeV. However, for highest energies there still exists a clear contamination from multiple charge states after the analysis magnet, most likely due to charge exchange in the high-energy acceleration tube. In the injector side a new injector magnet was installed and two new ion sources, sputtering and high brightness H−, have been commissioned. In the high energy area different beamlines for RBS, PIXE, TOF-ERDA and high energy ion beam lithography now exist. In this talk, this development will be discussed as well as the experimental results on how an accelerator can survive from 100 litres of cooling water within the SF6 insulating gas.

Relatore: Mikko Laitinen (University of Jyväskylä, Department of Physics)

Slides SNEAP2012_Mikko_Laitinen_v1.1.pdf

29 The Tandem accelerator at LNS and diagnostic aspects of the radioactive beams

The Tandem Van De Graaff accelerator (15MV) operating at LNS in Catania since early ‘80s, has been used in last years for accelerating ion beams, produced by means of the EXCYT facility at LNS. In order to guarantee an optimized beam injection of very low intensity radioactive beams (Ibeam > 104 pps), an efficient beam diagnostics has been developed in last years, mainly based on high sensitivity scintillating screens. We report on sensitivity and radiation hardness of several kinds of scintillators, including also a device based on microchannel plates.

Relatore: Dr. Luigi Cosentino (INFN-LNS)

Slides sneap_cosentino.pdf

30 Labec activity report

The Tandetron, manifactured by High Voltage Engineering Europe, is a 3MV terminal voltage tandem accelerator conceived, from its initial design, for both Ion Beam Analysis and Accelerator Mass Spectrometry operations. Although IBA and AMS share the same track inside the machine, all the essential settings needed to the beam transport can be easily retrieved for both operating modes at any time. A fast switching between IBA and AMS operations is thus made possible, since the system is equipped with two fully independent injecting lines - each provided with its own source(s), ours activity will be presente in this talk.

Relatore: Dr. Francesco Taccetti (INFN-FI)

Slides pres_labec_4_Giuntini_Taccetti__sneap12.pdf

13:00 Lunch

Poster Session

15:30 Coffee Break

Poster Session

Technical Report 4

31 Japan Earthquake of 2011 and the Effect on Electrostatics Accelerators

Since 1970, 35 National Electrostatics Corp. accelerator systems have been installed in Japan. These systems include the 12 MV tandem at Tsukuba University and the 20 MV folded tandem at Japan Atomic Energy Agency. The majority of these accelerator systems where in the most severally effected regions of the earthquake. The earthquake that occurred on March 11, 2011, is the most powerful to strike the region since the accelerator installations began. This talk will describe the earthquake and the effects on the various accelerators in the region.

Relatore: Dr. Greg Norton (National Electrostatics Corp.)

Slides Earthquake__G._Norton_SNEAP_2012.pdf

venerdì 5 ottobre

Closing Session

32 Sulphur Hexafluoride as a Stripper Gas for Tandem Accelerators

We have investigated the use of sulphur hexafluoride as a stripper gas in tandem accelerators. We have used the ANTARES accelerator system at ANSTO to measure charge state distributions for this gas. Results are reported at 4MV terminal voltage for injected negative ions ranging from carbon to uranium oxide. For iodine and thorium the distributions are extended across a range of energies of practical use for accelerator mass spectrometry, ion beam analysis and other accelerator applications. Charge state distributions using sulphur hexafluoride are found to have mean charge states up to 1 charge unit higher than, and to be broader than, corresponding distributions for argon gas, except in the case of carbon beams. SF6 is shown to provide significantly higher yields for charge states of heavy ions above the mean charge state. As a result, we now perform actinide AMS measurements with 9% yield to the 5+ charge state, compared to 4-5% achieved previously with argon gas.

Relatore: Sig. David Garton (ANSTO)

Slides SF6_stripper_gas_report_v2.pdf

33 Open Discussion: SNEAP Future

10:30 Coffee Break

Closing Session

34 Closing Remarks

Relatore: Sig. John McKay (Retired)

Slides Summary_Talk.pdf

35 Closure

Relatori: Augusto Lombardi (LNL), Davide Carlucci (LNL)

Slides D.Carlucci_SNEAP_2012_Oct_5th,_2012_Clousure.pdf