  We report the time resolved spectroscopy result from two observations of Cen
X-3, over one binary orbit with ASTROSAT and two binary orbit with NuSTAR.
NuSTAR covered two intensity states where the light curve showed transition in
count rate from first to second binary orbit by a factor of $\sim$ 3. A
phenomenological model comprising of partially absorbed powerlaw with smoothed
high energy cutoff, cyclotron absorption $\sim$ 24 keV and 6.4 keV iron
emission gave good fit for ASTROSAT observation. NuSTAR spectra required two
additional emission components, a broad one $\sim$ 5.7 keV and a narrow one
$\sim$ 6.9 keV. A weak secondary absorption feature at $\sim$ 11.6 keV and
$\sim$ 14.5 keV was seen in the residuals of the spectral fit for ASTROSAT and
NuSTAR data respectively. The secondary absorption energy showed no correlation
with the cutoff energy. Its strength varied within 0.1 to 0.6 keV with its
width $\sim$ 1.6 keV. Its energy and optical depth showed linear positive
correlation with the fundamental cyclotron line energy and depth respectively.
The cyclotron line energy showed anti-correlation to flux described by a
powerlaw with negative index and the secondary absorption also showed similar
trend to flux. Depth of secondary absorption was $\sim$ 45 \% and centroid
energy was $\sim$ 54 \% of fundamental. Depth and energy ratio of secondary to
fundamental lied within 2$\sigma$ deviation from 0.5. We suggest this secondary
absorption to be a redshifted dipolar cyclotron resonance feature exhibiting
sub-harmonic behaviour.
