The argonne fragment mass analyzer

摘要: The Fragment Mass Analyzer is being constructed for use in heavy-ion experiments with the ATLAS superconducting linear accelerator system at Argonne National Laboratory. It a triple-focussing recoil mass spectrometer, designed to separate nuclear reaction recoils from primary beam and disperse them M/Q (mass/unit charge) focal plane. main ion-optical elements are two electric dipoles magnetic dipole, (E) symmetrically placed before after magnet (M). spaced such that position energy dispersion (x/delta/sub E/) angle (theta/delta/sub of both vanish (energy focus). Here delta/sub E/ stands ..delta..E/E, fractional deviation central energy. energy-dispersionless EME configuration was first used by Cormier Stwertka Recoil Spectrometers Rochester, also chosen Spolaore et al. Spectrometer Laboratori Nazionali di Legnaro Padua. Although canceled, not, device performs as spectrometer. When mode, combination offers some distinct advantages over designs containing Wien filters or single electrostatic element.more » These include wider acceptances superior rejection (/approximately/10/sup /minus/12/). focus condition implies isochronous orbits particles having same but differing emission angles target, an important feature when pulsed accelerators like ATLAS. 8 refs., 4 figs., 1 tab.« less