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

Immersion coating, spray coating, stretching, and roll-reduction metho ds 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 me thod 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 prese nted. Four of the self-supporting Teflon films form the walls of an op en-ended cell used to increase the density of a polarized-hydrogen tar get [M.A. Ross et al., Nucl. Instr. and Meth. A 344 (1994) 307; W.A. D ezarn et al., these Proceedings (17th World Conf, of the INTDS, Bloomi ngton, IN, USA, 1994) Nucl. Instr, and Meth. A 362 (1995) 36]. At a wa ll thickness of 500 mu g/cm(2), roughly half the thickness of commerci ally available film, detection of recoil protons became possible.