1st Workshop on Mixed Ion Beam Delivery

8 Oct 2026, 00:00 → 10 Oct 2026, 14:00 Europe/Vienna

TU Wien, Vienna, Austria

David Ondreka, Elisabeth Renner (Technische Universität Wien (AT)), Marco Giuseppe Pullia

This two-day workshop on mixed-species ion beam delivery will take place at TU Wien in Vienna, Austria, from October 8–9, 2026, with an optional visit to the MedAustron center for ion beam therapy and research on October 10, 2026. 

The workshop will bring together experts to review recent experience with delivering mixed ion beams in synchrotron facilities – primarily for online monitoring research in carbon ion therapy – discuss key challenges in the field and explore new strategies for providing such beams to a broader user community.

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MixedBeamWorkshop26_Background.pdf

Thursday 8 October

08:30 → 09:00 Registration, Welcome coffee

09:00 → 10:30 Simulation tools for mixed-species beam dynamics in synchrotrons

Optional session on simulating mixed-species beam dynamics in synchrotrons. Tutorials and discussions.

Conveners: Matthias Kausel (MedAustron), Elisabeth Renner (Technische Universität Wien)

09:00 Welcome address

09:10 Overview of ongoing mixed-beam simulation activities at GSI

Speaker: Andrii Pastushenko (GSI Helmholtzzentrum für Schwerionenforschung)

09:20 Overview of ongoing mixed-beam simulation activities at TU Wien and MedAustron

Speaker: Katrin Holzfeind (Technische Universität Wien)

09:30 Xsuite tutorial

Speaker: Giovanni Iadarola (CERN)

10:30 → 11:00 Coffee break

11:00 → 12:00 Simulation tools for mixed-species beam dynamics in synchrotrons

Optional session on simulating mixed-species beam dynamics in synchrotrons. Tutorials and discussions.

Conveners: Matthias Kausel (MedAustron), Elisabeth Renner (Technische Universität Wien)

11:00 Simulating the acceleration of mixed beams with unequal A/Q

Acceleration of mixed beams with unequal A/Q constitutes an interesting option to enlarge the possible combination of ions delivered simultaneously from a synchrotron, with potential applications in particle therapy, plasma physics, nuclear physics, and materials research. In this scheme, two ion beams are injected sequentially using multi-turn injection and then independently captured and accelerated in the same magnetic fields at their respective revolution frequency by applying an individual RF program per ion. In order to design a synchrotron cycle for such a scheme and understand its limitations, one must ultimately be able to simulate it using tracking tools. Here, we report on how Xsuite can be used to simulate the effect of the RF for the second beam on the first beam. We also pose the question of how to simulate beam-beam effects like mutual space-charge or intra-beam scattering in this scheme.

Speaker: Andrii Pastushenko (GSI)

11:20 Q&A and discussion on synergies and needs

Speaker: Giovanni Iadarola (CERN)

12:00 → 13:30 Lunch break

12:45 → 13:30 Registration, welcome coffee

13:30 → 15:20 Mixed-species beams in synchrotrons: applications and ongoing activities

Conveners: Simone Savazzi (Fondazione CNAO), Lennart Volz (GSI Helmholtz Center for Heavy Ion Research GmbH)

13:30 Welcome address and introduction

Speaker: Elisabeth Renner (Technische Universität Wien)

13:45 Mixed ion beams for range probing: medical motivation

Speaker: Marco Giuseppe Pullia (CNAO)

14:05 Review of three years of mixed ion beam delivery with synchrotrons

Speaker: Elisabeth Renner (Technische Universität Wien)

14:30 NIMMS: compatibility with mixed-beam delivery

Speaker: Heli Huttunen (CERN)

14:50 HEARTS++ project

We present the current status of HEARTS++, a proposed European high-energy heavy-ion irradiation facility to be hosted at CERN. The project targets two critical gaps in the existing landscape: the growing shortage of beam time availability for European academic and industrial users, and the restricted energy range inherent to conventional cyclotron-based facilities.

Speaker: Edgar Cristopher Cortes Garcia (CERN)

15:05 Mixed-beam opportunities in plasma physics

Speaker: Dr Martin Schanz (GSI Helmholtzzentrum für Schwerionenforschung GmbH)

15:20 → 15:50 Coffee break

15:50 → 17:30 Mixed-beam generation

Conveners: Michael Galonska (GSI Helmholtzzentrum für Schwerionenforschung GmbH), Nadia Gambino (Medaustron EBG)

15:50 Mixed-beam generation in ion sources

Speakers: Luigi Celona (INFN), Michael Galonska (GSI Helmholtzzentrum für Schwerionenforschung GmbH)

16:15 LINACs in medical synchrotron facilities: considerations for mixed He-C beam transport

Speaker: Bernhard Schlitt (GSI Helmholtzzentrum for Heavy Ion Research)

16:40 Sequential Synchrotron Injection Schemes for Mixed Ion Beam Generation

Historically, mixed ion beams have been generated - often involuntarily - from a single ion source and simultaneously injected into a synchrotron. As it turns out, this approach is limited by 1) the injector hardware, such as e.g. the ion sources, LINAC cavities, and magnets that might not be able to accommodate the required charge-to-mass ratios (q/m), 2) the ion sources that potentially cannot produce the desired charge states, and 3) the requirement that both ions need to exhibit nearly-identical q/m.

An alternative approach to generating mixed ion beams is to sequentially inject the different ion species into the synchrotron. This enables the injection of ions with different q/m, that can or cannot be stripped to almost-identical q/m after pre-acceleration in the LINAC. Naturally, this sequential injection process significantly prolongs the cycle duration.

Currently, sequential multiturn injection schemes have been employed to generate a mixed helium and carbon ion beam in the MedAustron synchrotron (limited injector hardware), and to inject and accelerate a mixed bismuth and iron beam (different q/m) in SIS18 at GSI.

This talk aims to provide an overview of the acquired experience using sequential injection schemes at MedAustron and GSI, as well as highlighting advantages/disadvantages and challenges associated with sequential injection schemes. Moreover, measures to minimize the cycle prolongation are investigated and discussed, on a general basis as well as using the specific examples of SIS18 and the MedAustron synchrotron.

Speaker: Matthias Kausel (MedAustron)

17:05 Beyond the box: exotic mixed-beam generation ideas

Speaker: David Ondreka (GSI Helmholtzzentrum für Schwerionenforschung)

17:10 Discussion

19:00 → 22:00 Workshop Dinner

Friday 9 October

08:00 → 08:30 Morning coffee

08:30 → 09:40 Mixed-species beam dynamics in synchrotrons

Conveners: Alessio Mereghetti (CNAO), Edgar Cristopher Cortes Garcia (CERN)

08:30 Recap and overview

08:40 Slow extraction of mixed ion beams

Speaker: Andrii Pastushenko (GSI Helmholtzzentrum für Schwerionenforschung)

09:05 Acceleration of mixed beams with unequal A/Q

Acceleration of mixed beams with unequal A/Q, or dual-frequency acceleration, constitutes an interesting option to enlarge the possible combinations of ions delivered simultaneously from a synchrotron, with potential applications in particle therapy, plasma physics, nuclear physics, and materials research. In this scheme, two ion beams are injected sequentially using multi-turn injection and then independently captured and accelerated in the same magnetic fields at their respective revolution frequency by applying an individual RF program per beam. Recently, the feasibility of dual-frequency accelerations has been demonstrated at the GSI synchrotron SIS18 with low intensities of 56Fe25+ and 209Bi68+. In this contribution, we first give some general requirements and limitations for dual-frequency acceleration. Then, we report on results from the proof-of-principle experiment regarding the influence of the RF program for the second ion beam on the first ion beam and identify the physical origin of observed effects. Finally, we discuss the need for more systematic investigations to confirm our inferences and to study the beam-beam effects expected at higher intensities.

Speaker: David Ondreka

09:30 Summary from the simulation tools session

Speaker: Katrin Holzfeind (Technische Universität Wien)

09:40 → 10:40 Coffee break and Posters

10:40 → 12:00 Mixed-beam diagnostics and imaging systems

Conveners: Andrii Pastushenko (GSI), Heli Huttunen (University of Helsinki (FI))

10:40 Measuring mixed-beam properties in the accelerator complex

The commissioning and further development of mixed helium--carbon beam delivery benefit significantely from access to species-resolved beam properties throughout the accelerator complex. As conventional beam diagnostics generally measure the combined beam, dedicated methods are required to distinguish helium and carbon.

This talk discusses diagnostic approaches for different stages of the accelerator chain, covering the low-, medium-, and high-energy beam transport lines as well as the synchrotron.

Speaker: Elisabeth Renner (Technische Universität Wien)

11:05 Diagnostics to characterize the extracted mixed beam

Speaker: Felix Ulrich-Pur (Marietta-Blau Institut, TU Wien)

11:30 Mixed-beam range probing systems

Speaker: Lennart Volz (GSI Helmholtzzentrum für Schwerionenforschung)

12:00 → 13:15 Lunch break

13:15 → 14:45 Round table and panel discussion

14:45 → 15:15 Coffee break

15:15 → 16:30 Round table and panel discussion

Conveners: David Ondreka, Dr Marco Giuseppe Pullia, Elisabeth Renner (Technische Universität Wien)

Saturday 10 October

08:30 → 14:00 MedAustron facility visit