Very large array observations of 6 centimeter H2CO in the direction of Cassiopeia A

H2CO observations in the 110-111 transition (6 cm) obtained with the Very Large Array in the direction of the supernova remnant Cas A are presented. Absorption images are obtained with a resolution of 6″ and a sensitivity of ≳0.003. Molecular structures in the Perseus arm are observed between -34 an...

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Detalles Bibliográficos
Publicado: 2002
Materias:
Dust, extinction
ISM: clouds
ISM: individual (Cassiopeia A)
ISM: molecules
Supernova remnants
Acceso en línea:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0004637X_v575_n2I_p871_Reynoso
http://hdl.handle.net/20.500.12110/paper_0004637X_v575_n2I_p871_Reynoso
Aporte de:
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) de Universidad de Buenos Aires
id paper:paper_0004637X_v575_n2I_p871_Reynoso
record_format dspace
spelling paper:paper_0004637X_v575_n2I_p871_Reynoso2023-06-08T14:28:45Z Very large array observations of 6 centimeter H2CO in the direction of Cassiopeia A Dust, extinction ISM: clouds ISM: individual (Cassiopeia A) ISM: molecules Supernova remnants H2CO observations in the 110-111 transition (6 cm) obtained with the Very Large Array in the direction of the supernova remnant Cas A are presented. Absorption images are obtained with a resolution of 6″ and a sensitivity of ≳0.003. Molecular structures in the Perseus arm are observed between -34 and -49 km s-1. The distribution of the molecular gas is significantly clumpy. Seventy-two clumps could be identified, with sizes of 0.17 ± 0.05 pc, densities between 0.3 and 14 × 104 cm-3, and masses below 10 M ⊙. In agreement with previous studies, most of the clumps, if not all, appear to be dispersing. The high H2 column density to the west of Cas A accounts for the lack of optical emission in this region. Moreover, the optical extinction, estimated to be 8 mag toward the expansion center of Cas A, might explain why the supernova explosion was not observed in the 17th century. A major objective of the present survey is to search for signs of a possible interaction between Cas A and a western cloud. A striking correlation between the continuum emission and the H2CO absorption distribution, and slight spectral broadenings toward the west, are the only evidence that may suggest that Cas A is interacting with an external cloud. However, the evidence is not enough to draw any definitive conclusion. 2002 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0004637X_v575_n2I_p871_Reynoso http://hdl.handle.net/20.500.12110/paper_0004637X_v575_n2I_p871_Reynoso
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic Dust, extinction
ISM: clouds
ISM: individual (Cassiopeia A)
ISM: molecules
Supernova remnants
spellingShingle Dust, extinction
ISM: clouds
ISM: individual (Cassiopeia A)
ISM: molecules
Supernova remnants
Very large array observations of 6 centimeter H2CO in the direction of Cassiopeia A
topic_facet Dust, extinction
ISM: clouds
ISM: individual (Cassiopeia A)
ISM: molecules
Supernova remnants
description H2CO observations in the 110-111 transition (6 cm) obtained with the Very Large Array in the direction of the supernova remnant Cas A are presented. Absorption images are obtained with a resolution of 6″ and a sensitivity of ≳0.003. Molecular structures in the Perseus arm are observed between -34 and -49 km s-1. The distribution of the molecular gas is significantly clumpy. Seventy-two clumps could be identified, with sizes of 0.17 ± 0.05 pc, densities between 0.3 and 14 × 104 cm-3, and masses below 10 M ⊙. In agreement with previous studies, most of the clumps, if not all, appear to be dispersing. The high H2 column density to the west of Cas A accounts for the lack of optical emission in this region. Moreover, the optical extinction, estimated to be 8 mag toward the expansion center of Cas A, might explain why the supernova explosion was not observed in the 17th century. A major objective of the present survey is to search for signs of a possible interaction between Cas A and a western cloud. A striking correlation between the continuum emission and the H2CO absorption distribution, and slight spectral broadenings toward the west, are the only evidence that may suggest that Cas A is interacting with an external cloud. However, the evidence is not enough to draw any definitive conclusion.
title Very large array observations of 6 centimeter H2CO in the direction of Cassiopeia A
title_short Very large array observations of 6 centimeter H2CO in the direction of Cassiopeia A
title_full Very large array observations of 6 centimeter H2CO in the direction of Cassiopeia A
title_fullStr Very large array observations of 6 centimeter H2CO in the direction of Cassiopeia A
title_full_unstemmed Very large array observations of 6 centimeter H2CO in the direction of Cassiopeia A
title_sort very large array observations of 6 centimeter h2co in the direction of cassiopeia a
publishDate 2002
url https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0004637X_v575_n2I_p871_Reynoso
http://hdl.handle.net/20.500.12110/paper_0004637X_v575_n2I_p871_Reynoso
_version_ 1768545215490031616

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