Sasmirala Individual Information for NGC 3147
Description
NGC 3147 is a face-on spiral galaxy at a distance of D = 30.1 ± 4.5 Mpc [amanullah_spectra_2010] with a Sy 2 nucleus [veron-cetty_catalogue_2010], which is the best known candidate of a “true” (unabsorbed) type II Seyfert (e.g., [bianchi_ngc_2008, matt_suzaku_2012]). Note that the detailed multiwavelength study by [casasola_molecular_2008] found large amounts of inflowing gas in the central arcsecond (~ 150 pc) region of NGC 3147. The nucleus appears point-like at radio wavelengths even with VLBI [ulvestad_origin_2001]. After IRAS, NGC 3147 was observed with Spitzer/IRAC, IRS and MIPS. A compact dominating nucleus embedded within the spiral-like host emission was detected in the corresponding IRAC and MIPS images (see also [pahre_mid-infrared_2004]). The nuclear MIPS 24 μm flux is consistent with the value published in [shi_unobscured_2010]. The IRS LR staring-mode spectrum suffers from low S/N but indicates silicate 10 μm emission, PAH features and a shallow blue spectral slope in νFν-space (see also [shi_unobscured_2010]). Thus, the arcsecond-scale MIR SED is possibly host-dominated. We observed the nuclear region of NGC 3147 with Michelle in two N-band filters in 2010 and detected a compact MIR nucleus, which is possibly marginally resolved (FWHM(major axis)~ 0.69arcsec ~ 100 pc; PA~ 150∘). However, at least a second epoch with deep subarcsecond MIR imaging is required to confirm this extension. Our nuclear photometry is on average ~ 60% lower than the Spitzer spectrophotometry. We conclude that the nucleus of NGC 3147 is either jet-dominated as M87 or it possesses significant AGN-heated dust as expected from a torus.
- [amanullah_spectra_2010] R. Amanullah, C. Lidman, D. Rubin, G. Aldering, P. Astier, K. Barbary, M. S. Burns, A. Conley, K. S. Dawson, S. E. Deustua, M. Doi, S. Fabbro, L. Faccioli, H. K. Fakhouri, G. Folatelli, A. S. Fruchter, H. Furusawa, G. Garavini, G. Goldhaber, A. Goobar, D. E. Groom, I. Hook, D. A. Howell, N. Kashikawa, A. G. Kim, R. A. Knop, M. Kowalski, E. Linder, J. Meyers, T. Morokuma, S. Nobili, J. Nordin, P. E. Nugent, L. Östman, R. Pain, N. Panagia, S. Perlmutter, J. Raux, P. Ruiz-Lapuente, A. L. Spadafora, M. Strovink, N. Suzuki, L. Wang, W. M. Wood-Vasey, N. Yasuda, and The Supernova Cosmology Project. Spectra and hubble space telescope light curves of six type ia supernovae at 0.511 < z < 1.12 and the union2 compilation . ApJ , 716 pp. 712–738, June 2010.
- [bianchi_ngc_2008] S. Bianchi, A. Corral, F. Panessa, X. Barcons, G. Matt, L. Bassani, F. J. Carrera, and E. Jiménez-Bailón. NGC 3147: a `true' type 2 seyfert galaxy without the broad-line region . MNRAS , 385 pp. 195–199, March 2008.
- [casasola_molecular_2008] V. Casasola, F. Combes, S. García-Burillo, L. K. Hunt, S. Léon, and A. J. Baker. Molecular gas in NUclei of GAlaxies (NUGA). x. the seyfert 2 galaxy NGC 3147 . A&A , 490 pp. 61–76, October 2008.
- [matt_suzaku_2012] G. Matt, S. Bianchi, M. Guainazzi, X. Barcons, and F. Panessa. The suzaku x-ray spectrum of NGC 3147. further insights on the best "true" seyfert 2 galaxy candidate . A&A , 540 pp. 111, April 2012.
- [pahre_mid-infrared_2004] Michael A. Pahre, M. L. N. Ashby, G. G. Fazio, and S. P. Willner. Mid-infrared galaxy morphology along the hubble sequence . ApJS , 154 pp. 235–241, September 2004.
- [shi_unobscured_2010] Yong Shi, George H. Rieke, Paul Smith, Jane Rigby, Dean Hines, Jennifer Donley, Gary Schmidt, and Aleksandar M. Diamond-Stanic. Unobscured type 2 active galactic nuclei . ApJ , 714 pp. 115–129, May 2010.
- [ulvestad_origin_2001] James S. Ulvestad and Luis C. Ho. The origin of radio emission in low-luminosity active galactic nuclei: Jets, accretion flows, or both? . ApJL , 562 pp. L133–L136, December 2001.
- [veron-cetty_catalogue_2010] M.-P. Véron-Cetty and P. Véron. A catalogue of quasars and active nuclei: 13th edition . A&A , 518 pp. 10, July 2010.
Images
Optical image (DSS, red filter). Displayed are the central 4 arcmin with North being up and East to the left. The colour scaling is linear with white corresponding to the median background (BG) and black to the 0.01% pixels with the highest intensity.
Spitzer MIR images. Displayed are the inner 40 arcsec with North being up and East to the left. The colour scaling is logarithmic with white corresponding to median BG and black to the 0.1% pixels with the highest intensity. The label in the bottom left states instrument and central wavelength of the filter in micron (I: IRAC, M: MIPS).
Subarcsecond-resolution MIR images sorted by increasing filter central wavelength. Displayed are the inner 4 arcsec with North being up and East to the left. The colour scaling is logarithmic with white corresponding to median BG and black to the 75% of the highest intensity of all images in units of sig_bg. The inset image (where present; either bottom or top right) shows the central arcsecond of the PSF from the calibrator star, scaled to match the science target. The labels in the bottom left state instrument and filter names (C: COMICS, M: Michelle, T: T-ReCS, V: VISIR).
SEDs
MIR SED. The description of the symbols in all the SED plots (where present) is the following: Grey crosses and solid lines mark the Spitzer/IRAC, MIPS and IRS data. The colour coding of the other symbols is as follows: green for COMICS, magenta for Michelle, blue for T-ReCS and red for VISIR data. Darker-coloured solid lines mark spectra of the corresponding instrument. The black filled circles mark the nuclear 12 and 18 micron continuum emission estimate from the data (where present). The ticks on the top axis mark positions of common MIR emission lines, while the light grey horizontal bars mark wavelength ranges affected by the silicate 10 and 18 micron features.