Detalles de publicación

PP 011040

Resolving the nuclear dust distribution of the Seyfert 2 galaxy NGC 3081

C. Ramos Almeida (1), M. Sánchez-Portal (2), A. M. Pérez-García (3,4), J. A. Acosta-Pulido (3,4) , M. Castillo (2), A. Asensio Ramos (3,4), J. I. González-Serrano (5), A. Alonso-Herrero (6), J. M. Rodríguez Espinosa (3,4), E. Hatziminaoglou (7), D. Coia (2), I. Valtchanov (2), M. Povic (8), P. Esquej (6), C. Packham (9), B. Altieri (2) c
(1) Univ. Sheffield, (2) Herschel Science Centre, (3) IAC, (4) ULL, (5) IFC, (6) CAB, (7) ESO, (8) IAA, (9) Univ. Florida
We report far-infrared (FIR) imaging of the Seyfert 2 galaxy NGC 3081 in the range 70-500 µm, obtained with an unprecedented angular resolution, using the Herschel Space Observatory instruments PACS and SPIRE. The 11 kpc (∼70") diameter star-forming ring of the galaxy appears resolved up to 250 µm. We extracted infrared (1.6-500 µm) nuclear fluxes, that is active nucleus-dominated fluxes, and fitted them with clumpy torus models, which successfully reproduce the FIR emission with small torus sizes. Adding the FIR data to the near- and mid-infrared spectral energy distribution (SED) results in a torus radial extent of Ro =4±2 pc, as well as in a flat radial distribution of the clouds (i.e. the q parameter). At wavelengths beyond 200 µm, cold dust emission at T=28±1 K from the circumnuclear star-forming ring of 2.3 kpc (∼15") in diameter
starts making a contribution to the nuclear emission. The dust in the outer parts of the galaxy is heated by the interstellar radiation field (19±3 K).

 
Aceptado para publicación en MNRAS | Enviado el 2011-07-14 | Proyecto 3E4207, 3I0506, 3E4008, 3I0192, 3E0411