Integral field spectroscopy of HII region complexes: The outer disc of NGC-6946

Integral field spectroscopy obtained with the Potsdam Multi-Aperture Spectrophotometer Fiber Package (PPak) and the 3.5-m telescope at the Calar Alto Observatory has been used to study an outer H ii region complex in the well-studied galaxy NGC-6946. This technique provides detailed maps of the regi...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: García Benito, Rubén, Díaz Beltrán, Ángeles Isabel, Hägele, Guillermo Federico, Pérez Montero, E., López, J, Vílchez, J. M., Pérez, E., Terlevich, Elena, Terlevich, Roberto, Rosa González, D.
Formato: Articulo
Lenguaje:Inglés
Publicado: 2010
Materias:
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/82548
Aporte de:
id I19-R120-10915-82548
record_format dspace
institution Universidad Nacional de La Plata
institution_str I-19
repository_str R-120
collection SEDICI (UNLP)
language Inglés
topic Ciencias Astronómicas
H ii regions
ISM: abundances
Techniques: spectroscopic
spellingShingle Ciencias Astronómicas
H ii regions
ISM: abundances
Techniques: spectroscopic
García Benito, Rubén
Díaz Beltrán, Ángeles Isabel
Hägele, Guillermo Federico
Pérez Montero, E.
López, J
Vílchez, J. M.
Pérez, E.
Terlevich, Elena
Terlevich, Roberto
Rosa González, D.
Integral field spectroscopy of HII region complexes: The outer disc of NGC-6946
topic_facet Ciencias Astronómicas
H ii regions
ISM: abundances
Techniques: spectroscopic
description Integral field spectroscopy obtained with the Potsdam Multi-Aperture Spectrophotometer Fiber Package (PPak) and the 3.5-m telescope at the Calar Alto Observatory has been used to study an outer H ii region complex in the well-studied galaxy NGC-6946. This technique provides detailed maps of the region in different emission lines, yielding spatially resolved information about the physical properties of the gas. The configuration was chosen to cover the whole spectrum from 3600 up to 10-000-Å, allowing the measurement of the near-infrared [S-iii] lines. We selected four luminous knots to perform a detailed integrated spectroscopic analysis of these structures and of the whole PPak field of view (FOV). For all the knots the electron density has been found to be very similar and below 100 cm-3. The [O-iii] electron temperature was measured in knots A, B, C and in the integrated PPak field, and was found to be around 8000 K. The temperatures of [O-ii] and [S-iii] were estimated in the four cases. The elemental abundances computed from the 'direct method' are typical of high-metallicity disc H-ii regions, with a mean value of 12+log(O/H) = 8.65, comparable to what has been found in this galaxy by other authors for regions at similar galactocentric distance. Therefore a remarkable abundance uniformity is found despite the different excitations found throughout the nebula. However, due to the quality of the data, the electron temperatures and metallicities obtained have associated errors comparable to the typical dispersion found in empirical calibrations.Wolf-Rayet (WR) features have been detected in three of the knots, leading to a derived total number of WR stars of 125, 22 and 5 for knots A, C and B, respectively. The ratios of the numbers of WR to O stars are consistent with the prediction of Starburst99 for individual bursts with an age about 4-Myr. Knot D, with no WR features, shows weak Hα emission, low excitation and the lowest Hβ equivalent width, all of which points to a more evolved state.The integrated spectrum of the whole PPak FOV shows high excitation and a relatively evolved age that does not correspond to the individual knot evolutionary stages. Some effects associated with the loss of spatial resolution are also evidenced by the higher ionizing temperature that is deduced from the η' parameter measured in the integrated PPak spectrum with respect to that of the individual knots.
format Articulo
Articulo
author García Benito, Rubén
Díaz Beltrán, Ángeles Isabel
Hägele, Guillermo Federico
Pérez Montero, E.
López, J
Vílchez, J. M.
Pérez, E.
Terlevich, Elena
Terlevich, Roberto
Rosa González, D.
author_facet García Benito, Rubén
Díaz Beltrán, Ángeles Isabel
Hägele, Guillermo Federico
Pérez Montero, E.
López, J
Vílchez, J. M.
Pérez, E.
Terlevich, Elena
Terlevich, Roberto
Rosa González, D.
author_sort García Benito, Rubén
title Integral field spectroscopy of HII region complexes: The outer disc of NGC-6946
title_short Integral field spectroscopy of HII region complexes: The outer disc of NGC-6946
title_full Integral field spectroscopy of HII region complexes: The outer disc of NGC-6946
title_fullStr Integral field spectroscopy of HII region complexes: The outer disc of NGC-6946
title_full_unstemmed Integral field spectroscopy of HII region complexes: The outer disc of NGC-6946
title_sort integral field spectroscopy of hii region complexes: the outer disc of ngc-6946
publishDate 2010
url http://sedici.unlp.edu.ar/handle/10915/82548
work_keys_str_mv AT garciabenitoruben integralfieldspectroscopyofhiiregioncomplexestheouterdiscofngc6946
AT diazbeltranangelesisabel integralfieldspectroscopyofhiiregioncomplexestheouterdiscofngc6946
AT hageleguillermofederico integralfieldspectroscopyofhiiregioncomplexestheouterdiscofngc6946
AT perezmonteroe integralfieldspectroscopyofhiiregioncomplexestheouterdiscofngc6946
AT lopezj integralfieldspectroscopyofhiiregioncomplexestheouterdiscofngc6946
AT vilchezjm integralfieldspectroscopyofhiiregioncomplexestheouterdiscofngc6946
AT pereze integralfieldspectroscopyofhiiregioncomplexestheouterdiscofngc6946
AT terlevichelena integralfieldspectroscopyofhiiregioncomplexestheouterdiscofngc6946
AT terlevichroberto integralfieldspectroscopyofhiiregioncomplexestheouterdiscofngc6946
AT rosagonzalezd integralfieldspectroscopyofhiiregioncomplexestheouterdiscofngc6946
bdutipo_str Repositorios
_version_ 1764820488390967300