An internal-target technique was used to make the first measurements of the tensor analyzing power 7^20 of electron-deuteron elastic scattering in the four-momentum-transfer range of 2-3 fm _l . Polarized deuterium atoms were confined within a storage cell in the VEPP-3 electron storage ring in Novosibirsk to achieve a total target thickness of 3x 10 12 cm ~2, 15 times greater than was previously possible with an atomic-beam target alone. The results for T20 are in agreement with reasonable models of the deuteron wave function.

In anticipation of a new era of synchrotron radiation sources based on energy recovery linac techniques, we designed, built, and tested a short undulator magnet prototype whose features make optimum use of the unique conditions expected in these facilities. The prototype has pure permanent magnet (PPM) structure with 24 mm period, 5 mm diameter round gap, and is 30 cm long. In comparison with conventional undulator magnets it has the following: (i) full x-ray polarization control.-It may generate varying linear polarized as well as left and right circular polarized x rays with photon flux much higher than existing Apple-II-type devices. (ii) 40% stronger magnetic field in linear and approximately 2 times stronger in circular polarization modes. This advantage translates into higher x-ray flux. (iii) Compactness.-The prototype can be enclosed in a $20 cm diameter cylindrical vacuum vessel. These advantages were achieved through a number of unconventional approaches. Among them is control of the magnetic field strength via longitudinal motion of the magnet arrays. The moving mechanism is also used for x-ray polarization control. The compactness is achieved using a recently developed permanent magnet soldering technique for fastening PM blocks. We call this device a ''Delta'' undulator after the shape of its PM blocks. The presented article describes the design study, various aspects of the construction, and presents some test results.

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The Vibrating wire field-measuring technique presented here is dedicated to the problem of alignment of quadrupole magnets and is based on the following principle. The stretched wire has vibrational modes consisting of the fundamental mode and higher harmonics. The half wave length of the fundamental mode is equal to the length of the wire. Suppose there is a transverse magnetic field surrounding wire. If the frequency of the current in the wire is an eigenmode frequency of wire vibration, it will excite a corresponding harmonic. The strength and phase of excitation will depend on the field distribution along the wire. Using various frequencies and measuring amplitudes and phases of the resulting vibrations, one can extract information about the field distribution in order to reconstruct it. The field in turn shows the misalignment of quadrupoles.In comparison with the pulsed-wire method, see [1]-[4], the vibrating wire technique does not require the wire length to be longer than the length of the test region, and due to its extraordinary sensitivity it does not require the higher voltage for the long wire scheme. Therefore, it may be more appropriate for some projects.

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