New Concepts and Applications for Heavy Ion Acceleration
Paper Title Page
Laser-Ion Acceleration in Plasmas  
  • J. Schreiber
    LMU, Garching, Germany
  Chirped pulse amplification (CPA) laser systems such as the Advanced Titanium-Sapphire Laser (ATLAS) operated in the Centre for Advanced Laser Applications (CALA) at the Ludwig-Maximilians-University (LMU) Munich can now provide laser pulses with Petawatt peak power and ~30 fs duration. When tightly focussed onto a target, typically a (sub-)micrometer thin foil, electrons are driven relativistically and seperated from ions, so that they are dragged along. The rectified electric fields that both generate high charge states as well as accelerate ions are of order of the laser fields, ~1 to 100 MV/µm. I will review the physical processes at play and present the characteristics of ion sources, in particular the energy distributions that are accessible with current technology [1]. The fact that ions are energized by ultrashort laser pulses results in a number of intriguing and novel applications, for example time resolved investigation of processes that follow energy deposition in water [2]. I will also report on recent observations of acceleration of gold ions to MeV/u kinetic energy. The observed charge state and energy distributions challenge physical models and inspire nonlinear nuclear physics approaches [3].
[1] J. Schreiber, P. R. Bolton, and K. Parodi, Rev. Sci. Instrum., vol. 87, p. 071101, 2016.
[2] A. Prasselsperger et al., Phys. Rev. Lett., vol. 127, p. 186001, 2021.
[3] F. H. Lindner et al., Sci. Rep., vol. 12, p. 4784, 2022.
slides icon Slides MO1I1 [2.556 MB]  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
TUP05 Prototype Room Temperature Quadrupole Chamber with Cryogenic Installations 75
  • S. Aumüller, L.H.J. Bozyk, P.J. Spiller
    GSI, Darmstadt, Germany
  • K. Blaum
    MPI-K, Heidelberg, Germany
  The synchrotron SIS100 at FAIR accelerator complex at the GSI Helmholtzzentrum will generate heavy ion beams of ultimate intensities. As medium charge states have to be used, the probability for charge exchange in collisions with residual gas particles of such ions is much lager than for higher charge states. In the last years, several measures have lowered the residual gas density to extreme high vacuum conditions. For example 55% of the circumference of SIS18 have already been coated with NEG, which provides high and distributed pumping speed. Nevertheless, this coating does not pump nobel and nobel-like components, which have very high ionization cross sections. A cryogenic environment at e.g. 50-80K provides a high pumping speed for all heavy residual gas particles. The only typical residual gas particle that cannot be pumped at this temperature is hydrogen. With the pumping speed of an additional NEG coating in these areas, the pumping will be optimized for all residual gas particles. The installation of cryogenic installations in the existing room temperature synchrotron SIS18 at GSI has been investigated. Measurements on a prototype chamber and simulations of SIS18 with cryogenic installations based on these measurements are presented.  
DOI • reference for this paper ※  
About • Received ※ 21 June 2022 — Revised ※ 30 June 2022 — Accepted ※ 01 July 2022 — Issue date ※ 10 August 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
TUP06 Cryogenic Surfaces in a Room Temperature SIS18 Ioncatcher 79
  • L.H.J. Bozyk, S. Aumüller, P.J. Spiller
    GSI, Darmstadt, Germany
  For FAIR operation, the existing heavy ion synchrotron SIS18 at GSI will be used as booster for the future SIS100. In order to reach the intensity goals, medium charge state heavy ions will be used. Unfortunately, such ions have very high ionization cross sections in collisions with residual gas particles, yielding in beam loss and a subsequent pressure rise via ion impact stimulated gas desorption. To reduce the desorption yield, room temperature ioncatcher have been installed, which provide low desorption surfaces. Simulations including cryogenic surfaces show, that their high sticking probability prevents the vacuum system from pressure built-ups during operation. Such, the operation with heavy ion beams can be stabilized at higher heavy ion intensities, than solely with room temperature surfaces. A prototype ioncatcher containing cryogenic surfaces has been developed and built. The surfaces are cooled by a commercial coldhead, which easily allows this system being integrated into the room temperature synchrotron. The development and first laboratory tests including fast pressure measurements of this system will be presented.  
DOI • reference for this paper ※  
About • Received ※ 21 June 2022 — Accepted ※ 01 July 2022 — Issue date ※ 10 August 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
TUP07 Efficient Heavy Ion Acceleration with High Brilliance 83
  • C. Zhang
    GSI, Darmstadt, Germany
  • H. Podlech
    IAP, Frankfurt am Main, Germany
  It is challenging to realize an efficient and brilliant RFQ for accelerating high current heavy ion beams, as space charge effects are most pronounced at the low energy end. Here ’efficient’ means an as short as pos-sible accelerating structure with minimum RF power consumption, while ’brilliant’ means high beam transmission and low emittance growth. Using the > 9 m long HSI RFQ accelerator, one of the longest RFQs in the world, as an example, a promising solution has been presented.  
poster icon Poster TUP07 [1.134 MB]  
DOI • reference for this paper ※  
About • Received ※ 21 June 2022 — Accepted ※ 10 August 2022 — Issue date ※ 19 September 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
Recent Progress of Research and Development for the Cost Effective, Energy Efficient Proton Accelerator CYCIAE-2000  
  • T.J. Zhang, C. Wang
    CIAE, Beijing, People’s Republic of China
  Funding: This work was supported in part by the National Natural Science Foundation of China under Grant 12135020 and the basic research fund from the Ministry of Finance of China under Grant BRF201901
The MW class proton accelerators are expected to play important role in many fields, attracting institutions to continue research and tackle key problems. The CW isochronous accelerator obtains high power beam with higher energy efficiency, which is very attractive to many applications. Scholars generally believe that the energy limitation of the isochronous cyclotron is ~1GeV. In order to get higher beam power by the isochronous machine, enhancing the beam focusing become the most important issue. Adjusting the radial gradient of average magnetic field make the field distribution match the isochronism. When we adjust the radial gradient of peak field Bhill, the first order gradient is equivalent to the quadrupole field, the second order, to the hexapole field, and so on. Just like the synchrotron, there are quadrupole, hexapole magnet and so on, along the orbits so as to get higher energy, as all we know. If we adjust the radial gradient for peak field of an FFAG’s FDF lattice, and cooperate with the angular width (azimuth flutter) and spiral angle (edge focusing) of the traditional cyclotron pole, we can control the working path in tune diagram very flexibly. During enhancing the axial focusing, the beam intensity and energy of CW isochronous accelerator are significantly increased. And a 2GeV CW FFAG with 3mA of average beam intensity are designed. It is essentially an isochronous cyclotron although we use 10 folder of FDF lattices. The key difficulty is that the magnetic field and each order of gradient should be accurately adjusted in a large radius range. As a high power proton accelerator with high energy efficiency, we adopt high temperature superconducting (HTS) technology for the magnets. 15 RF cavities with Q value of 90000 provide energy gain per turn of ~15MeV to ensure the CW beam intensity reaches 3mA. A 1:4 scale, 15 ton HTS magnet and a 1:4 scale, 177MHz cavity have been completed. The results of such R & D will also be presented in this paper.
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
TH4C3 High Intensity Proton Beams at GSI (Heavy Ion) UNILAC 170
  • W.A. Barth, M. Miski-Oglu, U. Scheeler, H. Vormann, M. Vossberg, S. Yaramyshev
    GSI, Darmstadt, Germany
  • W.A. Barth, M. Miski-Oglu
    HIM, Mainz, Germany
  A significant part of the experimental program at FAIR is dedicated to pbar physics requiring a high number of cooled pbars per hour. The primary proton beam has to be provided by a 70 MeV proton linac followed by two synchrotrons. The new FAIR proton linac will deliver a pulsed high intensity proton beam of up to 35 mA of 36 µs duration at a repetition rate of 4 Hz. The GSI heavy ion linac (UNILAC) is able to deliver intense heavy ion beam for injection into SIS18, but it is not suitable for FAIR relevant proton beam operation. In an advanced machine investigation program it could be shown, that the UNILAC is able to provide for sufficient high intensities of CH3-beam, cracked (and stripped) in a supersonic nitrogen gas jet into protons and carbon ions. This new operational approach results in up to 3 mA of proton intensity at a maximum beam energy of 20 MeV, 100 µs pulse duration and a rep. rate of 4 Hz. For some time now, UNILAC proton beam operation with higher intensities has been offered as standard for users. Recent linac beam measurements will be presented, showing that the UNILAC is able to bridge the time until the FAIR-proton linac delivers high-intensity proton beams.  
slides icon Slides TH4C3 [3.539 MB]  
DOI • reference for this paper ※  
About • Received ※ 11 June 2022 — Revised ※ 28 June 2022 — Accepted ※ 10 August 2022 — Issue date ※ 29 September 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)