Sizes of Lightest Glueballs in SU(3) Lattice Gauge Theory

Standard Monte Carlo simulations have been performed on improved lattices to measure the wave functions and sizes of the scalar and tensor glueballs at four lattice spacings in the range $a= 0.05 - 0.145$ fm. Systematic errors from discretization and finite volume are studied. Our results in the continuum limit show that the size of the tensor state is approximately two times as large as that of the scalar glueball.