A treatment procedure for Gemini North/NIFS data cubes: application to NGC 4151

Autor(es)

Menezes, R. B. ^[1] ; Steiner, J. E. ^[1] ; Ricci, T. V. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Astron Geofis & Ciencias Atmosfer, BR-05508090 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Monthly Notices of the Royal Astronomical Society; v. 438, n. 3, p. 2597-2620, MAR 2014.
• Citações Web of Science: 26

Resumo

We present a detailed procedure for treating data cubes obtained with the Near-Infrared Integral Field Spectrograph (NIFS) of the Gemini North telescope. This process includes the following steps: correction of the differential atmospheric refraction, spatial re-sampling, Butterworth spatial filtering, `instrumental fingerprint' removal and Richardson-Lucy deconvolution. The clearer contours of the structures obtained with the spatial re-sampling, the high spatial-frequency noise removed with the Butterworth spatial filtering, the removed `instrumental fingerprints' (which take the form of vertical stripes along the images) and the improvement of the spatial resolution obtained with the Richardson-Lucy deconvolution result in images with a considerably higher quality. An image of the Br gamma emission line from the treated data cube of NGC 4151 allows the detection of individual ionized-gas clouds (almost undetectable without the treatment procedure) of the narrow-line region of this galaxy, which are also seen in an {[}O III] image obtained with the Hubble Space Telescope. The radial velocities determined for each one of these clouds seem to be compatible with models of biconical outflows proposed by previous studies. Considering the observed improvements, we believe that the procedure we describe in this work may result in more reliable analysis of data obtained with this instrument. (AU)

• Processo FAPESP: 12/21350-7 - Emissão de baixa ionização nuclear e circum-nuclear em galáxias massivas.
• Beneficiário: Tiago Vecchi Ricci
• Linha de fomento: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 12/02268-8 - Núcleos de galáxias no universo local: buracos negros supermassivos e arqueologia estelar de galáxias de alta e baixa massas
• Beneficiário: Roberto Bertoldo Menezes
• Linha de fomento: Bolsas no Brasil - Pós-Doutorado