A New Zero‐Field Paramagnetic Resonance Spectrometer
The construction of a new zero‐field paramagnetic resonance (ZFPMR) spectrometer is discussed. Spectrometer organization and construction details are presented for both resonant cavities and broadband traveling‐wave helices as sample holders. A new circuit diagram for a square wave magnetic field modulator with fast rise time is given. The performance of each kind of spectrometer is discussed with particular emphasis on investigation of paramagnetic rare earth ions with zero‐field splittings in diamagnetic host lattices.
Pressure effects on zero-field resonance. II. Gd3+ in various zircon structure compounds
A systematic investigation of the influence of hydrostatic pressure on the zero-field resonance of trivalent gadolinium has been made in a set of nine isomorphic crystals. The pressure coefficients of the rotational symmetric crystal field parameters (which are reliably determined by our experiment) do not only vary markedly in the absolute value with the compounds but also change sign. 
 
 
 
Die systematische Untersuchung des Einflusses von hydrostatischem Druck auf die Null-feldaufspaltung des dreiwertigen Gadoliniums wurde auf eine Serie von neun Kristallen gleicher Struktur ausgedehnt. Dabei fallt auf, das die Druckkoeffizienten der aus diesem Experiment zuverlassig bestimmbaren rotationssymmetrischen Kristallfeldparameter in den verschiedenen Verbindungen nicht nur dem Betrage nach stark variieren, sondern sogar Vorzeichenwechsel des Druckeffektes auftritt.
The REX-ISOLDE project
The Radioactive Beam Experiment REX-ISOLDE [1–3] is a pilot experiment at ISOLDE (CERN) testing the new concept of post acceleration of radioactive ion beams by using charge breeding of the ions in a high charge state ion source and the efficient acceleration of the highly charged ions in a short LINAC using modern ion accelerator structures. In order to prepare the ions for the experiments singly charged radioactive ions from the on-line mass separator ISOLDE will be cooled and bunched in a Penning trap, charge bred in an electron beam ion source (EBIS) and finally accelerated in the LINAC. The LINAC consists of a radiofrequency quadrupole (RFQ) accelerator, which accelerates the ions up to 0.3 MeV/u, an interdigital H-type (IH) structure with a final energy between 1.1 and 1.2 MeV/u and three seven gap resonators, which allow the variation of the final energy. With an energy of the radioactive beams between 0.8 MeV/u and 2.2 MeV/u a wide range of experiments in the field of nuclear spectroscopy, astrophysics and solid state physics will be addressed by REX-ISOLDE.