α-induced reactions
α-induced reactions can be measured in an in-beam experiment
or with the activation approach. In an in-beam experiment in
standard kinematics, the probe is irradiated with a α beam
provided by an accelerator and the number of reactions is determined
generally by the detection of the ejectiles of the reaction (e.g.,
the emitted photons in a (α,γ) reaction). For the
activation approach, the number of the unstable reaction products is
determined after the irradiation in a background-reduced setup. This
is usually realised by γ or x-ray spectroscopy. In more
complicated cases, alternative methods like, e.g., accelerator mass
spectrometry are used.
If α-induced reactions on unstable isotopes are to be
investigated inverse kinematics can be used, i.e., the roles of
probe and projectile are exchanged. The α probe is usually
realized as a gas target, a technically complicated system. If the
unstable isotopes are kept in a storage ring the reaction products
can be separated by their different tracks in the ring. Another
approach is to measure not only in inverse kinematics but in
addition also the time-reversed reaction (inverse reaction). Here,
the role of incoming and outgoing channel are exchanged which
sometimes yields in an easier experiment.
Experiments
ESR
Notre Dame
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