With modern detectors and synchrotron sources, it is now routine to collect complete data sets in 10–30 min. To make the most efficient use of these resources, it is desirable to automate the collection and processing of the diffraction data, ideally to a level at which multiple data sets can be acquired without any intervention. A scheme is described to allow fully automated data collection and processing. The design is modular, so that it can easily be interfaced with different beamline‐control programs and different data‐processing programs. An expert system provides a communication path between the data‐processing software and the beamline‐control software and takes decisions about the data collection based on project information provided by the user and experimental data provided by the data‐processing program.

Gamma-ray spectra of neutron-deficient isotopes between cerium (Z = 58) and gadolinium (Z = 64) have been investigated. New bands of states were identified in many even-even, odd-^4, and odd-odd nuclei. This Letter reports results on the ground-state bands in the even-even nuclei 1 58Ce 68 , 128 ' 130 ' 1 6oNd 6 8,7o,72, 134 ' HiSmn, 74, and 13M $Gd 7 4,76. The systematic trends of deformation are presented and compared with theoretical predictions. The lightest isotopes appear to be axially symmetric rotors with e 2 >. 0.3. PACS numbers: 21.10. Dr, 21.10.Ft, 23.20.Lv, 27.60. +j For nearly 25 years there have been experimental 1 and theoretical 2 indications that the region of atomic nuclei with Z > 50 and N < 82 should contain nuclei with considerable permanent ground-state deformation. Until now, experimental data 3 have been confined to the periphery of this region. However, theoretical interest has continued 4 and during the last few years new attempts 5 " 9 have been made to put these predictions on a more quantitative footing with calculations of which isotopes are most deformed, the size and type of deformation, and the manner in which the transition from sphericity (near Z = 50 and N = 82) to deformation occurs.Although the center of this deformed region appears to lie beyond the proton dripline (near N,Z = 64), most predictions indicate that an area of axially symmetric prolate rotors with e 2 -0.3 should occur in the lightest particle-bound Nd, Pm, and Sm isotopes. This Letter reports on a series of experiments aimed at extending data far into this region in order to test these estimates of shape.The most favorable method of production of neutron-deficient exotic nuclei in the ,4-130 region is through compound-nuclear reactions of heavy ions fusing at energies near the Coulomb barrier ( ~~ 4 MeV/nucleon). The bulk of the compound nuclei decay by charged-particle evaporation which leads to production of isotopes closer to stability. To investigate selectively nuclei approaching the proton dripline special detectors are required which allow some selection of reaction channels. In this Letter the isotopic origin of gamma rays was established by measurement of the multiplicities of coincident evaporated particles emitted during compound-nuclear cooling. 10 Standard techniques of gamma-ray spectroscopy were then used to investigate nuclear shapes through the deduction of decay schemes. This technique permits a significant advance in the experimental information on the v4 -130 region which enables us to make the first systematic tests of nuclear-shape predictions.Targets of 1-3 mg/cm 2 of enriched isotopes on -30-mg/cm 2 Pb backings were bombarded with heavy-ion beams from the Daresbury Laboratory Van de Graaff accelerator. A list of beam and target combinations is given in Table I. Gamma rays were detected in an array of four bismuth-germaniumoxide-shielded germanium detectors 11 placed at 135° to the beam direction. Neutrons were detected in a 1-m 2 array 10 of 37 NE213 liquid-scintillation detectors sit...

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