A novel Hadron Blind Detector (HBD) has been developed for an upgrade of the
PHENIX experiment at RHIC. The HBD will allow a precise measurement of
electron-positron pairs from the decay of the light vector mesons and the
low-mass pair continuum in heavy-ion collisions. The detector consists of a 50
cm long radiator filled with pure CF4 and directly coupled in a windowless
configuration to a triple Gas Electron Multiplier (GEM) detector with a CsI
photocathode evaporated on the top face of the first GEM foil.Comment: 4 pages, 3 figures, Quark Matter 2005 conference proceeding