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).
It may interest you
-
Red dwarfs are the most common stars in the galaxy. In recent years they have become key targets in the search for exoplanets. These stars are usually accompanied by rocky planets and due to their low brightness, their habitable zone is close to the star, making it easier to find planets that are within it. GJ 1002 is a red dwarf just one-eighth the mass of the Sun, located only 15.8 light-years away. Using radial velocity measurements from the ESPRESSO and CARMENES spectrographs, we have discovered the presence of two Earth-like and potentially habitable planets. The planets, GJ 1002 b and
Advertised on -
Stellar ages are key to several fields of astrophysics such as exoplanet research, galactic-archeology, and of course stellar physics. Obtaining the ages of stars is however not straightforward and requires stellar modeling. The most widely used technique only requires stellar colors or temperature and surface gravity, but the uncertainties are quite large. This technique is most efficient for stars belonging to clusters, as they were born from the same molecular cloud and share the same ages. In the last decades, based on the study of stellar acoustic waves, asteroseismology became the most
Advertised on -
H II regions are ionized nebulae associated with the formation of massive stars. They exhibit a wealth of emission lines in their spectra that form the basis for estimation of chemical composition. The amount of heavy chemical elements is essential to the understanding of important phenomena such as nucleosynthesis, star formation and chemical evolution of galaxies. For over 80 years, however, a discrepancy exists of a factor of around two between heavy-element abundances (the so-called metallicity) derived from the two main kinds of emission lines that can be measured in nebular spectra
Advertised on