ISOLDE Physics Group Meeting (PGM) and Seminar

Thursday 12 Nov 2026, 14:00 → 15:15 Europe/Zurich

508/1-001 (CERN)

14:00 → 14:10 General announcements

Newsletter, outreach

CERN matters

Budget and administration

Technical

General

Speakers: Hanne Heylen (CERN), Prof. Luis M Fraile (CERN)

14:10 → 14:15 Overview of ISOLDE activities

https://isolde.web.cern.ch/isolde-hall-activities-ls3

14:15 → 14:20 Safety announcements

Speakers: Hanne Heylen (CERN), Prof. Luis M Fraile (CERN)

14:20 → 14:25 Visits

Rota to be found on: https://cernbox.cern.ch/s/qbqEUB41tAvAzWa

Speakers: Hanne Heylen (CERN), Victoria Vedia (CERN)

14:25 → 14:30 AOB

Speakers: Amy Sparks (Paul Scherrer Institute (CH)), Carlotta Porzio (CERN), Christoph Schweiger (Max Planck Society (DE)), Hanne Heylen (CERN), Jessica Warbinek (CERN), Juliana Schell (Institut Fur Materialwissenschaft Universität Duisburg-Essen (DE)), Liss Vazquez Rodriguez (Max Planck Society (DE)), Prof. Luis M Fraile (CERN), Magdalena Kowalska (CERN), Patrick MacGregor (CERN), Peter Plattner, Tim Enrico Lellinger (Max Planck Institute for Nuclear Physics), Victoria Vedia (CERN)

14:30 → 15:15 ISOLDE seminar or Physics presentation by local group

Speaker: Svetlana Karpova (University of Geneva)

Title: Detector Development for Proton Computed Tomography: First Steps towards the ASTRA Range Telescope

Abstract:
Proton therapy places its dose with millimetre precision, but only if the proton range inside the patient is known. Today it is predicted from X-ray CT images through a conversion from Hounsfield units to proton stopping power, whose uncertainty forces clinics to add safety margins of about 3.5% of the range plus 1 to 2 mm. Proton computed tomography removes the conversion by imaging the patient with protons: each proton is tracked in and out, its residual energy is measured, and the relative stopping power is reconstructed directly, at lower dose. Existing prototypes record about one million protons per second, too slow for the clinic.

ASTRA (A Super-Thin RAnge telescope) is a proposed answer: a stack of 3 x 3 mm2 plastic scintillator bars read out by fast SiPMs, whose nanosecond signals should allow about 108 protons per second. A single-bar test bench at the University of Geneva was built to study light collection in real bars. Measurements with a 90Sr source and a 28 MeV proton beam at Birmingham confirmed the SiPM fast output as the timing channel, showed that crosslinked EJ-248M is far more robust than standard PVT, and demonstrated that a silicone pad doubles the collected light, so the bars can stay unwrapped. These results fix the design of the first ASTRA prototype.

Speakers: Annie Dolan, Carlotta Porzio (CERN), Hanne Heylen (CERN)