High-resolution CO observations towards the bright eastern knot of the SNR Puppis A

En:

Astron. Astrophys. 2008;480(2):439-443

Fecha:

2008

Formato:

application/pdf

Tipo de documento:

info:eu-repo/semantics/article
info:ar-repo/semantics/artículo
info:eu-repo/semantics/publishedVersion

Descriptores:

ISM: clouds -  ISM: molecules -  ISM: supernova remnants -  Data reduction -  Radio astronomy -  Signal to noise ratio -  Space telescopes -  ISM: clouds -  ISM: molecules

Descripción:

Aims.This paper reports molecular observations towards the bright eastern knot (BEK) in the SNR Puppis A, a feature where radio and X-ray studies suggest that the shock front is interacting with a dense molecular clump.Methods.We performed high-resolution millimetric observations towards the BEK of Puppis A using the SEST telescope in the CO -0 and 2-1 lines (beams of 45 and 23, respectively). More extended, lower angular resolution CO -0 observations taken from NANTEN archival data were also analyzed to obtain a complete picture.Results. In the velocity range near 16 km s-1, which is the Puppis A systemic velocity, our study revealed two important properties: (i) no dense molecular gas is detected immediately adjacent to the eastern border of the BEK and (ii) the molecular clump detected very close to the radiocontinuum maximum is probably located in the foreground along the line of sight and has not yet been reached by the SNR shock front. We propose two possible scenarios for explaining the absence of molecular emission eastwards of the BEK border of Puppis A. Either the shock front has completely engulfed and destroyed a molecular clump or the shock front is interacting with part of a larger cloud, and we do not detect CO emission immediately beyond it because the molecules have been dissociated by photodissociation and by reactions with photoionized material due to the radiative precursor. © 2008 ESO.
Fil:Paron, S. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.
Fil:Dubner, G. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.
Fil:Reynoso, E. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.

Identificador(es):

http://hdl.handle.net/20.500.12110/paper_00046361_v480_n2_p439_Paron

Derechos:

info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by/2.5/ar