Abbott, B (reprint author), NYU, New York, NY 10003 USA.
We report a search for effects of large extra spatial dimensions in p (p) over bar collisions at a center-of-mass energy of 1.8 TeV with the DO detector, using events containing a pair of electrons or photons. The data are in good agreement with the expected background and do not exhibit evidence for large extra dimensions. We set the most restrictive lower limits to date, at the 95% C.L. on the effective Planck scale between 1.0 and 1.4 TeV for several formalisms and numbers of extra dimensions.