出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：Many nuclear reactions important for nucleosynthesis are investigated by transfer reactions using
a radioactive ion beam on gas targets such as 1H, 2H, 3He and 4He. Since these measurements
are performed in inverse kinematics, the energies of the ejectiles are usually low with a strong
angular dependence in the laboratory system. Therefore, a new kind of detector is needed that
allows the detection of low-energy ions from a gas target with good energy and angle resolution
and a large angular coverage. TACTIC is a cylindrical time-projection chamber that can utilize
the target gas also as the drift medium so that no separation window is required. Moreover, the
reaction region is still separated from the drift region which allows for the higher beam currents
needed for impact energies far below the Coulomb barrier. The cylindrical design is possible by
the application of gas electron-multiplier (GEM) foils for the amplification of the weak electrondrift
signals. From the electron- drift times the ion track can be reconstructed while the collected
charge provides additional information about the ion species.
