Sasmirala Individual Information for NGC 1614

Description

NGC 1614 is a infrared-luminous heavily interacting spiral galaxy at a redshift of z = 0.0159 (D ~ 71 Mpc) with an active starburst nucleus, which possibly contains an AGN (see [vaisanen_nuclear_2012] for a recent detailed study). Optically, the nucleus has been classified as either an H II region (e.g., [veron-cetty_catalogue_2010]), a possible LINER [kim_optical_1995, veilleux_optical_1995] or an AGN/starburst composite [yuan_role_2010]. Indications for an obscured AGN come from X-ray spectroscopy [risaliti_hard_2000], while at radio wavelengths no compact nuclear source was detected (e.g., [hill_starburst_2001]). However, [vaisanen_nuclear_2012] rule out the presence of an obscured AGN based on the infrared spectral properties like absorption features and forbidden emission line ratios. The starburst nucleus is surrounded by a bright starburst ring with ~ 2arcsec  (~ 650 pc) diameter [alonso-herrero_ngc_2001]. Note that [vaisanen_nuclear_2012] argue that instead of a late-stage merger with a double nucleus, the companion galaxy survived the collision and is now more than 20 kpc away to the south-west. The first MIR observations of NGC 1614 were performed by [rieke_infrared_1972] followed by [lebofsky_extinction_1979], [aitken_question_1981] and [lonsdale_infrared_1984], [phillips_8-13_1984], [lawrence_observations_1985], [carico_iras_1988], [wright_recent_1988], and [wynn-williams_luminous_1993] after IRAS. [keto_subarcsecond_1992] obtained the first subarcsecond N-band image of NGC 1614 finding a complex resolved structure, which was further resolved into a roughly ring-like structure coinciding with the starburst ring by [miles_high-resolution_1996] using Palomar 5 m/Spectral-10 and [soifer_high-resolution_2001] using Keck/MIRLIN. Spitzer lacks the angular resolution to resolve the ring, which appears embedded within additional host emission in the corresponding IRAC and MIPS images. Furthermore, the IRAC 8.0 μm PBCD image is saturated in the centre and thus not used. We measure the nuclear flux in the IRAC 5.8 μm and MIPS 24 μm images and scale the IRS LR staring-mode spectrum accordingly. The resulting Spitzer MIR SED is to be regarded as an upper limit on the arcsecond-scale MIR emission, and the fluxes are still significantly lower than published in e.g., [engelbracht_metallicity_2008, u_spectral_2012]. It displays typical star formation features with strong PAH emission, weak silicate 10 μm absorption, and a red spectral slope in νF_ν-space (see also [brandl_mid-infrared_2006, bernard-salas_spitzer_2009, vaisanen_nuclear_2012]). In addition, NGC 1614 was observed with VISIR in the PAH2 filter in 2004 [siebenmorgen_nuclear_2008] and in the Q2 filter in 2006 (unpublished, to our knowledge), as well as with T-ReCS in the Si2 filter in 2006 [diaz-santos_understanding_2008], and with COMICS in the Q17.7 filter in 2008 [imanishi_subaru_2011]. The bright star burst ring was detected in all image despite varying S/N and resolution. The ring has not been fully resolved with a distinguishable nucleus in any case except possibly the Si2 image. Therefore, we just derive upper limits on the nuclear flux through PSF-scaling at the central position. These are on average ~ 80% lower than the Spitzer spectrophotometry. We conclude that from the subarcsecond MIR point of view there is no evidence for an AGN, which, if present, is the cause of less than 20% of the total MIR emission in the central ~ 1 kpc.

• [aitken_question_1981] D. K. Aitken, P. F. Roche, and M. M. Phillips. The question of extinction in active galactic nuclei - infrared spectral observations of NGC 1614, NGC 7469 and NGC 1275 . MNRAS , 196 pp. 101P–107P, September 1981.
• [alonso-herrero_ngc_2001] A. Alonso-Herrero, C. W. Engelbracht, M. J. Rieke, G. H. Rieke, and A. C. Quillen. NGC 1614: A laboratory for starburst evolution . ApJ , 546 pp. 952–965, January 2001.
• [bernard-salas_spitzer_2009] J. Bernard-Salas, H. W. W. Spoon, V. Charmandaris, V. Lebouteiller, D. Farrah, D. Devost, B. R. Brandl, Yanling Wu, L. Armus, L. Hao, G. C. Sloan, D. Weedman, and J. R. Houck. A spitzer high-resolution mid-infrared spectral atlas of starburst galaxies . ApJS , 184 pp. 230–247, October 2009.
• [brandl_mid-infrared_2006] B. R. Brandl, J. Bernard-Salas, H. W. W. Spoon, D. Devost, G. C. Sloan, S. Guilles, Y. Wu, J. R. Houck, D. W. Weedman, L. Armus, P. N. Appleton, B. T. Soifer, V. Charmandaris, L. Hao, J. A. Marshall Higdon, and T. L. Herter. The mid-infrared properties of starburst galaxies from spitzer-IRS spectroscopy . ApJ , 653 pp. 1129–1144, December 2006.
• [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.
• [diaz-santos_understanding_2008] Tanio Díaz-Santos, Almudena Alonso-Herrero, Luis Colina, Christopher Packham, James T. Radomski, and Charles M. Telesco. Understanding the 8 μm versus paα relationship on subarcsecond scales in luminous infrared galaxies . ApJ , 685 pp. 211–224, September 2008.
• [engelbracht_metallicity_2008] C. W. Engelbracht, G. H. Rieke, K. D. Gordon, J.-D. T. Smith, M. W. Werner, J. Moustakas, C. N. A. Willmer, and L. Vanzi. Metallicity effects on dust properties in starbursting galaxies . ApJ , 678 pp. 804–827, May 2008.
• [hill_starburst_2001] Tanya L. Hill, Charlene A. Heisler, Ray P. Norris, John E. Reynolds, and Richard W. Hunstead. Starburst or seyfert? adding a radio and far-infrared perspective to the investigation of activity in composite galaxies . AJ , 121 pp. 128–139, January 2001.
• [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.
• [keto_subarcsecond_1992] Eric Keto, Roger Ball, John Arens, Garrett Jernigan, and Margaret Meixner. Subarcsecond mid-infrared imaging of the nuclei of the infrared bright galaxies NGC 1614 and NGC 7469 . ApJ , 389 pp. 223–226, April 1992.
• [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.
• [lawrence_observations_1985] A. Lawrence, M. Ward, M. Elvis, G. Fabbiano, S. P. Willner, N. P. Carleton, and A. Longmore. Observations from 1 to 20 microns of low-luminosity active galaxies . ApJ , 291 pp. 117–127, April 1985.
• [lebofsky_extinction_1979] M. J. Lebofsky and G. H. Rieke. Extinction in infrared-emitting galactic nuclei . ApJ , 229 pp. 111–117, April 1979.
• [lonsdale_infrared_1984] C. J. Lonsdale, S. E. Persson, and K. Matthews. Infrared observations of interacting/merging galaxies . ApJ , 287 pp. 95–107, December 1984.
• [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.
• [phillips_8-13_1984] M. M. Phillips, D. K. Aitken, and P. F. Roche. 8-13 micron spectrophotometry of galaxies. i - galaxies with giant h II region nuclei . MNRAS , 207 pp. 25–33, March 1984.
• [rieke_infrared_1972] G. H. Rieke and F. J. Low. Infrared photometry of extragalactic sources . ApJL , 176 pp. L95, September 1972.
• [risaliti_hard_2000] G. Risaliti, R. Maiolino, and L. Bassani. The hard x-ray properties of the seyfert nucleus in NGC 1365 . A&A , 356 pp. 33–40, April 2000.
• [siebenmorgen_nuclear_2008] R. Siebenmorgen, M. Haas, E. Pantin, E. Krügel, C. Leipski, H. U. Käufl, P. O. Lagage, A. Moorwood, A. Smette, and M. Sterzik. Nuclear activity in nearby galaxies. mid-infrared imaging with the VLT . A&A , 488 pp. 83–90, September 2008.
• [soifer_high-resolution_2001] B. T. Soifer, G. Neugebauer, K. Matthews, E. Egami, A. J. Weinberger, M. Ressler, N. Z. Scoville, S. R. Stolovy, J. J. Condon, and E. E. Becklin. High-resolution mid-infrared imaging of infrared-luminous starburst galaxies . AJ , 122 pp. 1213–1237, September 2001.
• [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.
• [vaisanen_nuclear_2012] Petri Väisänen, Vinesh Rajpaul, Albert A. Zijlstra, Juha Reunanen, and Jari Kotilainen. The nuclear polycyclic aromatic hydrocarbon emission of merger system NGC 1614: rings within rings . MNRAS , 420 pp. 2209–2220, March 2012.
• [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.
• [wright_recent_1988] G. S. Wright, R. D. Joseph, N. A. Robertson, P. A. James, and W. P. S. Meikle. Recent star formation in interacting galaxies. III - evidence from mid-infrared photometry . MNRAS , 233 pp. 1–23, July 1988.
• [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

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.