NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-06-17 T12:30:43 PDT
Help | Comment | NED Home

For refcode 2007PASJ...59S.483S:
Retrieve 2 NED objects in this reference.
Please click here for ADS abstract

NED Abstract

Copyright by Astronomical Society of Japan. 2007PASJ...59S.483S Properties of UIR Bands in NGC6946 Based on Mid-Infrared Imaging and Spectroscopy with Infrared Camera on Board AKARI Sakon, I.; Onaka, T.; Wada, T.; Ohyama, Y.; Matsuhara, H.; Kaneda, H.; Ita, Y.; Ohyabu, S.; Kataza, H.; Fujishiro, N.; Ihara, C.; Ishigaki, M.; Ishihara, D.; Kim, W.; Okada, Y.; Takagi, T.; Tanabe, T.; Uemizu, K.; Ueno, M.; Usui, F.; Watarai, H.; Koo, B.-C.; Serjeant, S.; Nakagawa, T.; Matsumoto, T.; Murakami, H. Abstract. We present results on mid-infrared imaging and spectroscopic observations of the nearby late-type spiral NGC6946 with the Infrared Camera on board AKARI. Based on mid-infrared imaging with the S7 (7 microns) and S11(11 microns) bands, we found that the S7/S11 ratios have larger values in the arm region, containing many star-forming regions, than in the interarm. Slit spectra of an interarm and a star-forming region show a series of unidentified infrared (UIR) bands at 6.2, 7.7, 8.6, and 11.2 microns. The strengths of the 6.2, 7.7, and 8.6microns bands are larger relative to the 11.2microns band in the star-forming region, than in the interarm, even if the interstellar extinction of A_V_=3 mag towards the star-forming region is taken into account. The increase in the 6.2 microns and 7.7 microns features relative to the 11.2microns feature is consistent with the ionization model of PAHs. The ratio of the UIR features to the plateau emission under the 7.7 microns and 8.6 microns features and/or the ratio of the 7.6 microns/7.8 microns components in the 7.7 mmicrons feature increase in the star-forming region compared to the interarm. This variation can be accounted for by the hypothesis that the photo-evaporation of PAH clusters produce small free-flying PAHs in the star-forming region. The ratios of 6.2 microns/11.2 microns, 7.7 microns/11.2 microns, and 8.6 microns/11.2 microns may be tools to measure the star-formation activity in remote galaxies if these ratios and their variations are well examined and established for a large sample. Key Words: dust, extinction -- galaxies: individual (NGC 6946) -- galaxies: ISM -- galaxies: spirals -- infrared: galaxies
Retrieve 2 NED objects in this reference.
Please click here for ADS abstract

Back to NED Home