Spectral index of the H2O-maser emitting planetary nebula IRAS 17347-3139

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Five pages, 2 figures, accepted by MNRAS

Scientific paper

10.1111/j.1365-2966.2005.09592.x

We present radio continuum observations of the planetary nebula (PN) IRAS 17347-3139 (one of the only two known to harbour water maser emission), made to derive its spectral index and the turnover frequency of the emission. The spectrum of the source rises in the whole frequency range sampled, from 2.4 to 24.9 GHz, although the spectral index seems to decrease at the highest frequencies (0.79+-0.04 between 4.3 and 8.9 GHz, and 0.64+-0.06 between 16.1 and 24.9 GHz). This suggests a turnover frequency around 20 GHz (which is unusual among PNe, whose radio emission usually becomes optically thin at frequencies < 10 GHz), and a relatively high emission measure (1.5 x 10^9 cm^{-6} pc). The radio continuum emission has increased by a factor of ~1.26 at 8.4 GHz in 13 years, which can be explained as expansion of the ionized region by a factor of ~1.12 in radius with a dynamical age of ~120 yr and at an expansion velocity of ~5-40 km/s. These radio continuum characteristics, together with the presence of water maser emission and a strong optical extinction suggest that IRAS 17347-3139 is one of the youngest PNe known, with a relatively massive progenitor star.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Spectral index of the H2O-maser emitting planetary nebula IRAS 17347-3139 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Spectral index of the H2O-maser emitting planetary nebula IRAS 17347-3139, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Spectral index of the H2O-maser emitting planetary nebula IRAS 17347-3139 will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-465088

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.