We report the few hundred second anti-correlated soft lags between soft and
hard energy bands in the source GX 339-4 using RXTE observations. In one
observation, anti-correlated soft lags were observed using the ISGRI/INTEGRAL
hard energy band and the PCA/RXTE soft energy band light curves. The lags were
observed when the source was in hard and soft intermediate states, i.e., in a
steep power-law state.We found that the temporal and spectral properties were
changed during the lag timescale. The anti-correlated soft lags are associated
with spectral variability during which the geometry of the accretion disk is
changed. The observed temporal and spectral variations are explained using the
framework of truncated disk geometry. We found that during the lag timescale,
the centroid frequency of quasi-periodic oscillation is decreased, the soft
flux is decreased along with an increase in the hard flux, and the power-law
index steepens together with a decrease in the disk normalization parameter. We
argue that these changes could be explained if we assume that the hot corona
condenses and forms a disk in the inner region of the accretion disk. The
overall spectral and temporal changes support the truncated geometry of the
accretion disk in the steep power-law state or in the intermediate state.Comment: published in ApJ, 9 pages, 8 figure
