Central star formation in an early-type galaxy I~Zw~81 in the Bootes void
| Autor: | Divya Pandey, Kanak Saha, Ananta C. Pradhan, Sugata Kaviraj |
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| Jazyk: | angličtina |
| Rok vydání: | 2022 |
| Předmět: | |
| Popis: | The origin of star-formation in customarily passively evolving early-type massive galaxies is poorly understood. We present a case study of a massive galaxy, I~Zw~81, inside the Bootes void. The void galaxy is known to host an active galactic nuclei (AGN). Our detailed 2D decomposition of the surface brightness distribution in the $Canada$ $France$ $Hawaii$ $Telescope$ ($CFHT$) g- and r-bands revealed multiple structural components such as a nuclear point source, a bar, a ring, and an inner exponential disk followed by an outer low surface brightness (LSB) disk. I~Zw~81 turns out to be a disk-dominated galaxy with lenticular morphology. The modelling of the multi-wavelength spectral energy distribution (SED) shows that the galaxy is star-forming (SF), and belongs to the blue cloud. We find that the optical (g$-$r) color of the bar is bluer than the disks, and the far- and near-ultraviolet emission inside the galaxy observed with Ultraviolet Imaging Telescope (UVIT) onboard {\em AstroSat} is concentrated in the central few kpc region enclosing the bar. The strong bar might be playing a pivotal role in driving the gas inflow and causing SF activity in tandem with the minor merger-like interactions as evident from the deep $CFHT$ data. The low-luminosity AGN is insufficient to quench the central SF. The results are peculiar from the standpoint of a massive barred lenticular galaxy. Accepted for publication in ApJ |
| Databáze: | OpenAIRE |
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