Star formation activity in the neighbourhood of W-R 1503-160L star in
  the mid-infrared bubble N46
  In order to investigate star formation (SF) processes in extreme
environments, we have carried out a multi-wavelength analysis of the
mid-infrared bubble N46, which hosts a WN7 Wolf-Rayet (W-R) star. We have used
13CO line data to trace an expanding shell surrounding the W-R star containing
about five condensations within the molecular cloud associated with the bubble.
The W-R star is associated with a powerful stellar wind having a mechanical
luminosity of ~4 x 10^37 ergs/s. A deviation of the H-band starlight mean
polarization angles around the bubble has also been traced, indicating the
impact of stellar wind on the surroundings. The Herschel temperature map shows
a temperature range of ~18 - 24 K toward the five molecular condensations. The
photometric analysis reveals that these condensations are associated with the
identified clusters of young stellar objects, revealing ongoing SF process. The
densest among these five condensations (peak N(H_2) ~9.2 x 10^22 cm^-2 and A_V
~ 98 mag) is associated with a 6.7 GHz methanol maser, an infrared dark cloud,
and the CO outflow, tracing active massive SF within it. At least five compact
radio sources (crss) are physically linked with the edges of the bubble and
each of them is consistent with the radio spectral class of a B0V - B0.5V type
star. The ages of the individual infrared counterparts of three crss (~1 - 2
Myr) and a typical age of WN7 W-R star (~4 Myr) indicate that the SF activities
around the bubble are influenced by the feedback of the W-R star.
