We have measured the spin-lattice relaxation rate 1/T-1 in an as-grown sing
le crystal of YNi2B2C (T-c = 13.8 K) in the superconducting state down to 0
.9 K. 1/T-1 shows no Hebel-Slichter peak just below T-c, decreasing sharply
as T-3, and followed by a slow dependence of 1/T-1 proportional to T at lo
w temperatures. The pairing state is discussed on the basis of T-1 result.
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