A study of the star forming regions in the spiral galaxy NGC 2336 using
  the Ultraviolet Imaging Telescope (UVIT)
  We present a far-UV (FUV) and near-UV (NUV) imaging study of recent star
formation in the nearby spiral galaxy NGC 2336 using the Ultraviolet Imaging
Telescope (UVIT). NGC 2336 is nearly face-on in morphology and has a
multi-armed, branching spiral structure which is associated with star forming
regions distributed mainly along the spiral arms and the co-rotation ring
around the bar. We have identified 72 star forming knots in the disk, of which
only two are in the inter-arm regions and 6 in the co-rotation ring. We have
tabulated their positions and estimated their luminosities, sizes, star
formation rates, colors, ages and masses. The ages and masses of these star
forming knots were estimated using the Starburst99 stellar evolutionary
synthesis models. The star forming knots have FUV and NUV mean sizes of 485 pc
and 408 pc respectively and mean stellar masses of 9.8 $\times 10^{5}$
M$_{\odot}$ that range from 5.6 $\times 10^{5}$ to 1.1 $\times 10^{6}$
M$_{\odot}$. Their star formation rates vary from 6.9 $\times 10^{-4}$ to 2.2
$\times 10^{-2}$ M$_{\odot}$/yr in NUV and from 4.5 $\times 10^{-4}$ to 1.8
$\times 10^{-2}$ M$_{\odot}$/yr in FUV. The FUV-NUV colour of the knots is
found to be bluest in the central region and becomes progressively redder as
the radius increases. Our results suggest that star formation in disks with
spiral structure is driven by the spiral density wave and is best traced by UV
imaging as it encompasses clusters spanning a wide range of star forming ages
and stellar masses.
