In-flight production of an isomeric beam of N
arXiv:2202.01981 · doi:10.1016/j.nima.2022.166612
Abstract
An in-flight beam of N was produced via the single-neutron adding (,) reaction in inverse kinematics at the recently upgraded Argonne Tandem Linear Accelerator System (ATLAS) in-flight system. The amount of the N beam which resided in its excited 0.120-MeV isomeric state (T s) was determined to be 40(5)% at a reaction energy of 7.9(3) MeV/, and 24(2)% at a reaction energy of 13.2(2) MeV/. The isomer measurements took place at an experimental station m downstream of the production target and utilized an Al beam-stopping foil and a HPGe Clover detector. Composite N beam rate determinations were made at the experimental station and the focal plane of the Argonne in-flight radioactive ion-beam separator (RAISOR) with Si E-E telescopes. A Distorted Wave Born Approximation (DWBA) approach was coupled with the known spectroscopic information on N in order to estimate the relative N isomer yields and composite N beam rates. In addition to the observed reaction-energy dependence of the isomer fraction, a large sensitivity to angular acceptance of the recoils was also observed.
21 pages, 7 figures