On some problems of large superconducting magnets

Following a general introduction to the subject (Section I), the first part of the present review (Section II) is devoted to uncertainties of analytical and numerical analyses of energy dissipation in superconducting accelerator magnets working at relatively high ramp rate. The loss experimental techniques are discussed as well as the source of error in the measurements. The correlation between the interstrand resistance of Rutherford structures and quench current behaviour of superconducting magnets are considered. In the second part of this review (Section III) some important problems of the cooling of insertion quadrupoles for Large Hadron Collider (CERN) are presented. Experimental results below 2 K are interpreted by possible self-sustained pumping based on quantum- mechanical fountain effect in superfluid /sup 4/He. (25 refs).