We have observed ultraslow propagation of matched pulses in a parametric amplifying hot sodium vapor. A fractional delay of more than 1 and a gain of 28 have been simultaneously achieved for a probe pulse of width 100 ns, accompanying a conjugate Stokes pulse with similar gain and delay under a strong coupling beam. The results are compared with the preceding work by Boyer et al. [Phys. Rev. Lett. 99, 143601 (2007)].
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