THIN TEFLON FILM WALLS FOR A POLARIZED-GAS TARGET-CELL

Immersion coating, spray coating, stretching, and roll-reduction methods have been explored in work to produce pinhole-free films of Teflon that are 5 cm X 30 cm in area and less than 500 mu g/cm(2) thick. A method to produce these films by rolling thicker, commercially available films will be described. The defining characteristics and limitations encountered with each of the other preparation methods also are presented. Four of the self-supporting Teflon films form the walls of an open-ended cell used to increase the density of a polarized-hydrogen target [M.A. Ross et al., Nucl. Instr. and Meth. A 344 (1994) 307; W.A. Dezarn et al., these Proceedings (17th World Conf, of the INTDS, Bloomington, IN, USA, 1994) Nucl. Instr, and Meth. A 362 (1995) 36]. At a wall thickness of 500 mu g/cm(2), roughly half the thickness of commercially available film, detection of recoil protons became possible.