The Møller Polarimeter for MAMI

The polarization of high-energy electrons can conveniently be measured by means of Moller scattering from polarized electrons in a magnetized ferromagnetic target. This process exhibits in the limit of high energies (E ≥ 100 MeV) still relatively large, energy independent and well known analysator strengths. Furthermore, the laboratory cross section in the kinematical range suitable for polarimeter applications is large $$ \frac{{d\sigma }}{{d\Omega }}({\Theta _{cm}} = 90^\circ ) = Z \cdot 0.18{\text{ }}barn/sr$$ and energy-independent.

Spin Physics at MAMI

Kidney size in childhood sonographical growth charts for kidney length and volume

Kidney size was determined in a sonographic study of 325 children without kidney pathology. Real-time ultrasound equipment adjusted for the pediatric age group, provided standardized renal biometry. Outer kidney diameters showed a linear correlation to somatic developmental parameters. Renal volume was established by the formula for an ellipsoid and showed good correlation to body weight. Growth charts for kidney length and volume in childhood are constructed and provide the basis for objective intra- and interindividual determination of renal size.

Source of Polarized Electrons for MAMI B

A source of polarized electrons has been set up in order to inject polarized electrons into the 855 MeV c.w. electron accelerator MAMI B at the Mainz nuclear physics institute. It is based on photoemission of the 3/5 semiconductor GaAsP and will provide a d.c. current of 100 µA with a beam emittance of 1π mm mrad, and a polarization of about 40%.