High-field specific heat of the spin-fluctuation system UAl2

Measurements of the low-temperature specific heat, both in 0- and 7-T applied field, and magnetic susceptibility on polycrystalline, unannealed single-crystal and annealed single-crystal samples of UA${\mathrm{l}}_2$ show no sample dependence for these properties to ±5%, in contrast to recent results for Ti${\mathrm{Be}}_2$. Measurements of the specific heat of the annealed single crystal of UA${\mathrm{l}}_2$ from 2 to 23 K in fields to 12.5 T and from 4 to 16 K in fields to 17 T indicate a partial (∼40%) suppression of the spin-fluctuation contribution, which occurs at 2 K in 12.5 T, and the possible existence of a small competing effect which increases the specific heat with increasing field above 4 K. These results are compared with recent magnetization and magnetoresistivity results which indicate suppression of spin fluctuations in UA${\mathrm{l}}_2$ between 15 and 20 T.