GANIL-SPIRAL 2 facilities
  • Accelerators
  • Available beams
  • Experimental areas
    • ARIBE
    • D1
    • D2
    • D3-D6 / LISE
    • D5
    • DESIR
    • G1 / VAMOS
    • G2
    • G3
    • G4
    • IRRSUD
    • LIRAT
    • NFS – Neutrons for Science
    • S3 – Super Separator Spectrometer
  • Instrumentation
    • AGATA
    • FAZIA
    • INDRA
    • LPCTrap
    • MUST2
    • NEDA
    • PARIS
    • REGLIS3
    • S3 Low Energy Branch
    • SIRIUS



MUST2 (MUr a STrip 2) is a telescope array for the detection of the light ions emitted in direct reactions using exotic ion beams. It was built by a collaboration including GANIL, IPN Orsay and IRFU/SPhN.
The MUST2 was specifically designed to optimize the exploitation of the exotic beams and the quality of the observable measurements.


Scientific goals

The MUST2 detector was conceived to carry out research programs on the evolution of shell structure as a function of the isospin degree of freedom by doing direct nuclear reactions induced by radioactive beams. Experiments have been done at the GANIL (the Large National Heavy Ion Accelerator at Caen, Grand Accélérateur National d’Ions Lourds) facility, using SPIRAL beams in the SPEG or in the VAMOS areas, or fragmented beams produced in the LISE areas. Recenlty experiments were also carried out at RIKEN using the beams of the RIBF machine or the fragmented beams delivered in the RIPS area.

The MUST2 was specifically designed to optimize the exploitation of the exotic beams and the quality of the observable measurements.

In the years 2003-2006, the nuclear structure and reaction groups of CEA-Saclay, IRFU/SPhN, CNRS IN2P3 IPNO and of GANIL have developed and built the device with the technical divisions of these institutes : the IRFU SEDI (for the ASIC Mate : Must2 Asic Time and Energy), the GANIL acquisition-electronics group, and the IPNO detector division for the telescope detectors and the mechanics.
MUST2 represents the state of the art in the field of the telescope arrays.

Since 2010, this system is composed by a set of 8 telescopes for the measurement of energy, positions and time of flight of the light charged particles; each module consists of 3 detection stages: a 300µm-thick double-sided Silicium strip (DSSD) with an active area of 10 by 10 cm2, backed up by a second stage of 3mm-thick Silicium-Lithium and a 3 cm-thick CsI.


Technical description

The reactions produced by the radioactive beams on light targets (typically proton and deuton using CH2 and CD2 targets, respectively) are measured in inverse kinematics; the light recoil charged particles (p,d,t,3,4He …) have to be identified and their characteristicshave to be measured with good resolution: we need to measure time, energy and position to reconstruct the time of flight, momentum and total kinetic energy and the trajectories. The first device developed for these measurements was the MUST (MUrs de STrips) array used since 1999 till 2004.

The goals for the MUST2 project were to develop a new device to improve the angular coverage, the granularity and resolutions compared to the previous MUST, and the objective was also to combine efficiently this n system for the particle spectroscopy with the gamma particle detection systems like EXOGAM, having clover detectors located around the reaction target. The MUST2 project has included the building of the detector, the design and realisation of its electronics and the coupling to the Data Acquisition system at GANIL.

More information on technical aspects:



LPC Caen
Universidad de Santiago de Compostela Béatriz Fernandez-Dominguez
University of Surrey


Contact (GANIL)

Olivier Sorlin:


More information: