Sasmirala Individual Information for IRAS 08572+3915
Description
IRAS 08572+3915 is a galaxy pair with two overlapping spirals with a separation of ~ 6arcsec (~ 6 kpc) [sanders_ultraluminous_1988]. The north-western galaxy is an ultra-luminous infrared galaxy at a redshift of z = 0.0584 (D ~ 254 Mpc) with an active nucleus classified optically either as H II [veron-cetty_catalogue_2010], LINER [kim_optical_1995, veilleux_optical_1995, veilleux_new_1999], or Sy 2/starburst composite [yuan_role_2010]. We adopt the latter classification. After its discovery with IRAS, IRAS 08572+3915 was observed in the N-band by [carico_iras_1988] with the Palomar 5 m, [wynn-williams_luminous_1993] with IRTF/BOLO1 in 1986/87, [miles_high-resolution_1996] with Palomar 5 m/SpectroCam-10 in 1993, by [soifer_high_2000] with Keck/LWS and MIRLIN in 1998, and [gorjian_10_2004] with Palomar 5 m/MIRLIN in 2000. IRAS 08572+3915 remained unresolved in all these observations. It was also observed with Spitzer/IRAC, IRS and MIPS, where a marginally resolved MIR nucleus without any other host emission was detected. In particular, the south-eastern galaxy remains undetected. Note that the IRAC 8.0 μm PBCD image is partly saturated and thus not used. Our IRAC 5.8 μm and MIPS 24 μm photometry matches the values published in [u_spectral_2012]. The IRS LR staring mode spectrum exhibits extremely deep silicate 10 and 18 μm absorption, no prominent PAH emission and a red spectral slope in νFν-space (see also [spoon_detection_2006, levenson_deep_2007, imanishi_spitzer_2007]). The properties of the MIR SED favour the existence of a highly obscured AGN in IRAS 08572+3915 as proposed by [imanishi_energy_2000, imanishi_spitzer_2007]. IRAS 08572+3915 was observed with COMICS in the Q17.7 filter in 2008 [imanishi_subaru_2011]. We find the detected MIR nucleus to be possibly marginally resolved (FWHM ~ 0.63arcsec ~ 690 pc), which however needs to be verified with at least another epoch of subarcsecond MIR imaging. Our nuclear Q17.7 flux is significantly higher than the value published in [imanishi_subaru_2011] but agrees with the Spitzer spectrophotometry. Therefore, we use the latter to compute our 12 and 18 μm continuum emission estimates corrected for the silicate absorption. The absence of any strong emission features indicates that putative MIR emission-line producing regions are heavily extincted (similar to, e.g., NGC 4945; [perez-beaupuits_deeply_2011]).
- [carico_iras_1988] David P. Carico, D. B. Sanders, B. T. Soifer, J. H. Elias, K. Matthews, and G. Neugebauer. The IRAS bright galaxy sample. III - 1-10 micron observations and coadded IRAS data for galaxies with l(IR) equal to or greater than 10 to the 11th solar luminosities . AJ , 95 pp. 356–373, February 1988.
- [gorjian_10_2004] V. Gorjian, M. W. Werner, T. H. Jarrett, D. M. Cole, and M. E. Ressler. 10 micron imaging of seyfert galaxies from the 12 micron sample . ApJ , 605 pp. 156–167, April 2004.
- [imanishi_energy_2000] Masatoshi Imanishi and C. C. Dudley. Energy diagnoses of nine infrared luminous galaxies based on 3-4 micron spectra . ApJ , 545 pp. 701–711, December 2000.
- [imanishi_spitzer_2007] Masatoshi Imanishi, C. C. Dudley, Roberto Maiolino, Philip R. Maloney, Takao Nakagawa, and Guido Risaliti. A spitzer IRS low-resolution spectroscopic search for buried AGNs in nearby ultraluminous infrared galaxies: A constraint on geometry between energy sources and dust . ApJS , 171 pp. 72–100, July 2007.
- [imanishi_subaru_2011] Masatoshi Imanishi, Keisuke Imase, Nagisa Oi, and Kohei Ichikawa. Subaru and gemini high spatial resolution infrared 18 μm imaging observations of nearby luminous infrared galaxies . AJ , 141 pp. 156, May 2011.
- [kim_optical_1995] D.-C. Kim, D. B. Sanders, S. Veilleux, J. M. Mazzarella, and B. T. Soifer. Optical spectroscopy of luminous infrared galaxies. i. nuclear data . ApJS , 98 pp. 129, May 1995.
- [levenson_deep_2007] N. A. Levenson, M. M. Sirocky, L. Hao, H. W. W. Spoon, J. A. Marshall, M. Elitzur, and J. R. Houck. Deep mid-infrared silicate absorption as a diagnostic of obscuring geometry toward galactic nuclei . ApJL , 654 pp. L45–L48, January 2007.
- [miles_high-resolution_1996] J. W. Miles, J. R. Houck, T. L. Hayward, and M. L. N. Ashby. High-resolution mid-infrared imaging of infrared-luminous galaxies . ApJ , 465 pp. 191, July 1996.
- [perez-beaupuits_deeply_2011] J. P. Pérez-Beaupuits, H. W. W. Spoon, M. Spaans, and J. D. Smith. The deeply obscured AGN of NGC 4945. i. spitzer-IRS maps of [ne v], [ne II], h2 0-0 s(1), s(2), and other tracers . A&A , 533 pp. 56, September 2011.
- [sanders_ultraluminous_1988] D. B. Sanders, B. T. Soifer, J. H. Elias, B. F. Madore, K. Matthews, G. Neugebauer, and N. Z. Scoville. Ultraluminous infrared galaxies and the origin of quasars . ApJ , 325 pp. 74–91, February 1988.
- [soifer_high_2000] B. T. Soifer, G. Neugebauer, K. Matthews, E. Egami, E. E. Becklin, A. J. Weinberger, M. Ressler, M. W. Werner, A. S. Evans, N. Z. Scoville, J. A. Surace, and J. J. Condon. High resolution mid-infrared imaging of ultraluminous infrared galaxies . AJ , 119 pp. 509–523, February 2000.
- [spoon_detection_2006] H. W. W. Spoon, A. G. G. M. Tielens, L. Armus, G. C. Sloan, B. Sargent, J. Cami, V. Charmandaris, J. R. Houck, and B. T. Soifer. The detection of crystalline silicates in ultraluminous infrared galaxies . ApJ , 638 pp. 759–765, February 2006.
- [u_spectral_2012] Vivian U, D. B. Sanders, J. M. Mazzarella, A. S. Evans, J. H. Howell, J. A. Surace, L. Armus, K. Iwasawa, D.-C. Kim, C. M. Casey, T. Vavilkin, M. Dufault, K. L. Larson, J. E. Barnes, B. H. P. Chan, D. T. Frayer, S. Haan, H. Inami, C. M. Ishida, J. S. Kartaltepe, J. L. Melbourne, and A. O. Petric. Spectral energy distributions of local luminous and ultraluminous infrared galaxies . ApJS , 203 pp. 9, November 2012.
- [veilleux_new_1999] Sylvain Veilleux, D. B. Sanders, and D.-C. Kim. New results from a near-infrared search for hidden broad-line regions in ultraluminous infrared galaxies . ApJ , 522 pp. 139–156, September 1999.
- [veilleux_optical_1995] S. Veilleux, D.-C. Kim, D. B. Sanders, J. M. Mazzarella, and B. T. Soifer. Optical spectroscopy of luminous infrared galaxies. II. analysis of the nuclear and long-slit data . ApJS , 98 pp. 171, May 1995.
- [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.
- [wynn-williams_luminous_1993] C. G. Wynn-Williams and E. E. Becklin. Luminous infrared galaxies - sizes at 10-32 microns . ApJ , 412 pp. 535–540, August 1993.
- [yuan_role_2010] T.-T. Yuan, L. J. Kewley, and D. B. Sanders. The role of starburst-active galactic nucleus composites in luminous infrared galaxy mergers: Insights from the new optical classification scheme . ApJ , 709 pp. 884–911, February 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.