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A new model for the infrared emission of IRAS F10214+4724. Andreas Efstathiou European University Cyprus. Introduction to IRAS F10214+4724. Discovered by Rowan-Robinson et al (1991) Gravitationally lensed by a factor of 10 - 100 Similar to Seyfert 2 galaxies in optical-UV
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A new model for the infrared emission of IRAS F10214+4724 Andreas Efstathiou European University Cyprus SED2011 conference
Introduction to IRAS F10214+4724 • Discovered by Rowan-Robinson et al (1991) • Gravitationally lensed by a factor of 10 - 100 • Similar to Seyfert 2 galaxies in optical-UV • Large quantity of molecular gas and bright in the submillimeter • Similar to local ULIRGs? SED2011 conference
Starburst model of Efstathiou, Rowan-Robinson & Siebenmorgen (2000) • Stellar population synthesis model of Bruzual & Charlot • Radiative transfer that includes effect of small grains/PAHs (Siebenmorgen & Krugel) • Simple model for the evolution of giant molecular clouds SED2011 conference
Fit to Arp220 with the Efstathiou et al model (Farrah et al 2003) SED2011 conference
00183-7111 – A young starburst? SED2011 conference
Mid-IR spectroscopy of AGN • 8-13mm spectrophotometry from the ground by Roche and collaborators • Type 2 AGN showed moderate silicate absorption features • Type 1 AGN featureless • Discovery of silicate emission features in the Spitzer spectra of quasars by Siebenmorgen et al and Hao et al. SED2011 conference
Average spectra of Hao et al SED2011 conference
Tapered disc of Efstathiou & Rowan-Robinson (1995) SED2011 conference
Tapered disc model of NGC1068 (Galliano et al 2003) SED2011 conference
Grid of tapered disc models • Computed a grid of 36 tapered disc models • Vary outer to inner disc radius in the range 20 to 100 • Vary equatorial 1000A optical depth in the range 750 to 1250 • Vary torus opening angle in the range 30-60degrees • Compute spectra for 74 inclinations SED2011 conference
Distribution of silicate strength of tapered disc models (blue) – AGN of Spoon et al shown in red SED2011 conference
As previous slide but including all galaxies of Spoon et al with EW < 0.07 SED2011 conference
Distribution of silicate strength of all tapered disc models + NLR dust with a covering factor of 5% SED2011 conference
Fit to the Hao et al Seyfert 2 average with a tapered disc and NLR dust SED2011 conference
Phoenix • A new code that calculates the ultraviolet to mm emission of galaxies • Incorporates the stellar population synthesis model of Bruzual & Charlot • Incorporates the starburst model of Efstathiou, Rowan-Robinson & Siebenmorgen • Treats multiple scattering from grains SED2011 conference
ResultsfromPhoenix SED2011 conference
Fit to the SED of a spiral galaxy SED2011 conference
Model of Efstathiou (2006) • The model assumes four components • A torus viewed edge-on • Dust at a temperature of 600K and a covering factor of 2% • Dust at a temperature of 200K and a covering factor of 15% • A highly obscured starburst SED2011 conference
New model of F10214 that fits Herschel data • The model assumes an additional component of NLR dust at a temperature of 80K • The covering factor of NLR dust is very high. It is very likely that we have stronger gravitational lensing of the NLR than the torus SED2011 conference
Conclusions • We have a fairly good understanding of the infrared emission of starburst galaxies and AGN • IRAS F10214+4724 is very special. Its unique spectrum is probably due to the gravitational lensing of the emission of NLR clouds. SED2011 conference