Molecular Gas Toward the Planetary Nebula K 3-35

Details Molecular Gas Toward the Planetary Nebula K 3-35 Molecular Gas Toward the Planetary Nebula K 3-35

Jun 2006

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2006rmxac..26..176t&link_type=abstract

XI IAU Regional Latin American Meeting of Astronomy (Eds. L. Infante & M. Rubio) Revista Mexicana de Astronomía y Astrofísica (S

Astronomy and Astrophysics

Astronomy

Scientific paper

K 3-35, is a very young PN particularly interesting because it is one of the two PNe that exhibits water maser emission which, in the case of K 3-35, is present in the central region as well as at the enormous distance of 5000 AU from the center. Water masers are not supposed to be found at such an enormous distance in an evolved star, where the physical conditions required to pump the water maser ( n_{H2} ≈ 10^{8} cm^{-3}, T_K ≈ 500) are not expected to exist. It has been proposed that the shocks driven by the bipolar jet could be creating the physical conditions necessary to pump the distant water-vapor masers. However, the presence and persistence of water molecules in these regions is still puzzling, probably related to some shielding mechanism due to the presence of high density molecular gas that protects water molecules against the ionizing radiation of the central star. A full understanding of this shielding mechanism requires first the characterization of the physical conditions of the molecular gas around the planetary nebula together with detailed modeling studies. All available data strongly suggest that K 3-35 is an extremely young planetary nebula in which we are observing the first stages of formation of collimated bipolar outflows. Then, any information about the chemistry and physical parameters of the gas in K 3-35 is very important to understand the characteristics of such a particular object. In this work, we present a search of molecular emission toward K 3-35 and the first detection of HCO^+ (J = 1 - 0) molecular emission from which we derived the value for the K 3-35 molecular mass: M ≈ 0.15M_&sun;. This result suggests that this PN has a massive neutral envelope which could be responsible for the shielding mechanism that prevents water molecules from being destroyed by the central star ionizing radiation and also can provide the physical conditions to favor the maser emission at large distances. By comparing the molecular-to-ionized mass ratio with the relative abundance of HCO+ to HCN, we have plotted the point which corresponds to K 3-35 in an evolutive sequence for young PNe showing that K 3-35 is in a very early stage of its evolution. We report new spectra of the water masers present in this PN as well as upper limits for the detection of the molecules SiO, H^{13}CN, H^{13}CO, HNC, HCN, HC_3OH, HC_5N, CS, HC_3N, ^{13}CO, CN and NH_3.

Affiliated with

Also associated with

No associations

Rating

Molecular Gas Toward the Planetary Nebula K 3-35 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 Molecular Gas Toward the Planetary Nebula K 3-35, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Molecular Gas Toward the Planetary Nebula K 3-35 will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1478990