Eur. Phys. J. A 13, 59-62 (2002)
In-beam gamma-ray spectroscopy with exotic beams at the NSCL
T. Glasmacher1, 2, B.V. Pritychenko1, 2, P.D. Cottle3, R.W. Ibbotson1, K.W. Kemper3 and H. Scheit31 National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI, 48824, USA
2 Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824, USA
3 Department of Physics, Florida State University, Tallahassee, FL 32306, USA
(Received: 1 May 2001)
Abstract
Projectile fragmentation provides radioactive beams at intermediate velocities
(
v/c=0.3-0.5) by physical means of fragment separation. With the development of
position-sensitive photon detectors it has become possible to measure the
energies
and directions of photons emitted in-flight from such fast-moving exotic beams.
This allows the reconstruction of the photons' energies emitted from an exotic
projectile with high accuracy.
It can be advantageous to employ photon
detection in experiments with exotic beams since photons can traverse matter
easily and their attenuation can be calculated.
Experiments with standard luminosities can
be carried out at intermediate beam energies with thick secondary targets
(order
of g/cm
2) and very low incident beam rates (order of particle/s or less).
Experimental success in this field is strongly correlated with
the development of photon detectors such as position-sensitive scintillation
detectors or segmented germanium detectors.
In-beam gamma-ray spectroscopy of fast exotic beams
has been successfully used at all projectile fragmentation facilities
in intermediate-energy heavy-ion inelastic scattering experiments,
knockout reactions and fragmentation reactions.
Here, we focus on experimental results for
neutron-rich exotic nuclei
in the
-shell. Measurements and detector developments
carried out at the
NSCL at Michigan State University during the last four years are discussed.
27.30.+t -

25.70.Bc - Elastic and quasielastic scattering.
25.70.De - Coulomb excitation.
© Società Italiana di Fisica, Springer-Verlag 2002