New Maser Emission from Nonmetastable Ammonia in NGC 7538. II. Green Bank Telescope Observations Including Water Masers

Details New Maser Emission from Nonmetastable Ammonia in NGC 7538. II. Green Bank Telescope Observations Including Water Masers New Maser Emission from Nonmetastable Ammonia in NGC 7538. II. Green Bank Telescope Observations Including Water Masers

2011-10-11

arxiv.org/abs/1110.2238v2

Astronomy and Astrophysics

Astrophysics

Galaxy Astrophysics

7 pages, 4 figures, 3 tables; accepted to AJ; color figures only on arxiv; revised to include references and minor proof chang

Scientific paper

We present new maser emission from ^{14}NH_3 (9,6) in NGC 7538. Our observations include the known spectral features near v_LSR = -60 km/s and -57 km/s and several more features extending to -46 km/s. In three epochs of observation spanning two months we do not detect any variability in the ammonia masers, in contrast to the >10-fold variability observed in other ^{14}NH_3 (9,6) masers in the Galaxy over comparable timescales. We also present observations of water masers in all three epochs for which emission is observed over the velocity range -105 km/s < v_LSR < -4 km/s, including the highest velocity water emission yet observed from NGC 7538. Of the remarkable number of maser species in IRS 1, H_2O and, now, ^{14}NH_3 are the only masers known to exhibit emission outside of the velocity range -62 km/s < v_LSR < -51 km/s. However, we find no significant intensity or velocity correlations between the water emission and ammonia emission. We also present a non-detection in the most sensitive search to date toward any source for emission from the CC^{32}S and CC^{34}S molecules, indicating an age greater than \approx 10^4 yr for IRS 1-3. We discuss these findings in the context of embedded stellar cores and recent models of the region.

Affiliated with

Also associated with

No associations

Rating

New Maser Emission from Nonmetastable Ammonia in NGC 7538. II. Green Bank Telescope Observations Including Water Masers 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 New Maser Emission from Nonmetastable Ammonia in NGC 7538. II. Green Bank Telescope Observations Including Water Masers, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and New Maser Emission from Nonmetastable Ammonia in NGC 7538. II. Green Bank Telescope Observations Including Water Masers will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-471234