Sasmirala Individual Information for ESO 297-18
Description
ESO 297-18 is a highly inclined spiral galaxy at a redshift of z = 0.0252 (D ~ 103 Mpc) that harbours an AGN with optical Sy 2 classification [veron-cetty_catalogue_2010]. This buried AGN [ueda_suzaku_2007] belongs to the nine-month BAT AGN sample. It was observed with Spitzer/IRAC and IRS and appears as a compact nuclear source with extended host emission tracing the inclined spiral in the IRAC 5.8 and 8.0 μm images. The IRS LR staring-mode spectrum shows a prominent silicate 10 μm absorption feature with PAH and [Ne II] emission, indicating significant star formation. The MIR spectrum peaks around ~ 15 μm in νFν-space. We observed ESO 297-18 in 2007 with VISIR in four narrow N-band filters during one night. The MIR nucleus is only weakly detected in all images without any sign of host emission. It appears very compact, but the low S/N prevents any extension analysis. Our new measurement of the nuclear fluxes is consistent with the values for the SIV and PAH2 filters, which have already been published in [gandhi_resolving_2009]. Interestingly, these fluxes are on average ~ 52% lower than those of the Spitzer spectrophotometry and indicate a different MIR SED slope without the silicate 10 μm absorption feature.
- [gandhi_resolving_2009] P. Gandhi, H. Horst, A. Smette, S. Hönig, A. Comastri, R. Gilli, C. Vignali, and W. Duschl. Resolving the mid-infrared cores of local seyferts . A&A , 502 pp. 457–472, August 2009.
- [ueda_suzaku_2007] Yoshihiro Ueda, Satoshi Eguchi, Yuichi Terashima, Richard Mushotzky, Jack Tueller, Craig Markwardt, Neil Gehrels, Yasuhiro Hashimoto, and Stephen Potter. Suzaku observations of active galactic nuclei detected in the swift BAT survey: Discovery of a ``New type'' of buried supermassive black holes . ApJ , 664 pp. L79–L82, August 2007.
- [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.