Date of Original Version
We present analytical and numerical results for the low frequency autocorrelation function of the 1-d s=1/2 Heisenberg antiferromagnet at low temperature and various fields. Our results are in good agreement with NMR data.
Gerhard Müller and Hans Beck. Temperature and field dependence of autocorrelation functions for the one-dimensional Heisenberg antiferromagnet. J. Magnetism and Magn. Materials 15-18 (1980), 689-690.