The correlation of target-like and projectile-like fragments can be an instrumental tool in investigating the multinucleon transfer mechanism. In laboratories with large angular acceptance separators, such methods are readily applied at significant angles away from the beam axis. With separators closer to 0°, at Coulomb barrier energies, it is a more challenging venture; In direct kinematics, the projectile-like fragments move with very shallow angles backward along the beam, and hence are hard to detect. In this report, recent advances of the simultaneous detection of both fragments with the in-flight gas-filled separator RITU will be discussed. Starting with how the germanium detector array JUROGAM can be used for the determination of the excitation energy of the multinucleon transfer products. In more recent years, JUROGAM has been used in tandem with a CD-type silicon detector in direct kinematics experiments to detect the projectile-like fragments that move backwards closely along the beam. With the results of these experiments, a new specialized Big Ultra-Large Long Enclosure for Transfer products (BULLET) target chamber will be introduced to more effectively research the multinucleon transfer process around 0° angles in the actinide region.
Landsman et al. (2026) studied this question.