The 48Ca+181Ta reaction: Cross section studies and investigation of neutron-deficient 86 ≤ Z ≤ 93 isotopes

Abstract Fusion-evaporation reactions with the doubly magic projectile 48 Ca were used to access neutron-deficient nuclei around neptunium at the velocity filter SHIP, and investigated using the COMPASS decay spectroscopy station. With the use of digital electronics, several isotopes produced via neutron, proton, and α evaporation channels were identified by establishing correlated α -decay chains with short-lived sub-μs members. Data are given on decay chains stemming from 225,226 Np, 225 U, and 222,223 Pa. New information on the isotopes 225,226 Np and 222 Pa was obtained. Production cross sections of nuclei in the region using a variety of projectiles are discussed. The measured production cross-sections indicate that the usual advantages of using 48 Ca as a beam projectile to produce nuclei Z >100 are absent in the production of these slightly lighter nuclei.