2018/11/07 by L G Dahmer-Hahn, Luis Gabriel Dahmer-Hahn, Rogério Riffel +14
Physics and Astronomy · #Astronomy #Astronomy and Astrophysical Research #Astrophysics #Galaxies: Formation, Evolution, Phenomena #Galaxy #Milky Way #Physics #Population #Star formation #Stars #Stellar kinematics #Stellar population #Stellar, planetary, and galactic studies #Velocity dispersion #astro-ph.GA
paper · pdf · doi:10.1093/mnras/sty3051
12 pages, 9 figures, accepted at MNRAS
arxiv created 2018/11/07 · openalex publication_date 2018/11/14 · openalex created_date 2018/11/16 · arxiv updated 2018/11/28 · openalex updated_date 2026/08/06
We map optical and near-infrared (NIR) stellar population properties of the inner 320 × 535 pc2 of the elliptical galaxy NGC 1052. The optical and NIR spectra were obtained using the Gemini Integral Field Units of the GMOS instrument and NIFS, respectively. By performing stellar population synthesis in the optical alone, we find that this region of the galaxy is dominated by old (t > 10 Gyr) stellar populations. Using the NIR, we find the nucleus to be dominated by old stellar populations, and a circumnuclear ring with younger (∼2.5 Gyr) stars. We also combined the optical and NIR datacubes and performed a panchromatic spatially resolved stellar population synthesis, which resulted in a dominance of older stellar populations, in agreement with optical results. We argue that the technique of combining optical and NIR data might be useful to isolate the contribution of stellar population ages with strong NIR absorption bands. We also derive the stellar kinematics and find that the stellar motions are dominated by a high (∼240 km s−1) velocity dispersion in the nucleus, with stars also rotating around the centre. Lastly, we measure the absorption bands, both in the optical and in the NIR, and find a nuclear drop in their equivalent widths. The favoured explanation for this drop is a featureless continuum emission from the low luminosity active galactic nucleus.