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The IUCF High Intensity Polarized Ion Source (HIPIOS)(1) has been described in detail in reference [Der92], and has a design based on a source in operation at Triangle Universities Nuclear Laboratory described in reference [Cle95]. It uses a cold atomic beam technology with an electron cyclotron resonance (ECR) ionizer.

In the atomic beam system a hydrogen (or deuterium) gas is dissociated in an rf discharge and formed into a slow beam of atoms as it moves through a nozzle cooled to . This beam is polarized by electron spin as it moves through a set of sextupole magnets. These magnets focus the atoms with electron spins parallel to the local field and defocus the atoms with anti-parallel spins. The electron polarization is then transferred to the nucleus by initiating an rf transition which interchanges populations of atomic hyperfine states. The neutral atomic beam is then ionized by impact with fast electrons in magnetically confined plasma heated by electron cyclotron resonance. The beam is extracted from the ECR ionizer at 2 keV into an rf buncher which shapes the beam bunch and accelerates it to 20 keV. The exit section of the source uses a combination of a bend, a spherical electrostatic channel, and two spin rotation solenoids to change the polarization of the beam from longitudinal to normal before entering the beam transfer line. Just prior to entering the beam line 1 (BL1) the beam is accelerated to 600 keV.

Michael A. Lisa
Tue Apr 1 08:52:10 EST 1997