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Register a new userJ1649+2635: A Grand-Design Spiral with a Large Double-Lobed Radio Source
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We report the discovery of a grand-design spiral galaxy associated with a double-lobed radio source. J1649+2635 (z = 0.0545) is a red spiral galaxy with a prominent bulge that it is associated with a L$_{1.4{rm GHz}}sim$10$^{24}$WHz$^{-1}$ double-lobed radio source that spans almost 100kpc. J1649+2635 has a black hole mass of M$_{rm BH} sim$ 3--7 $times$ 10$^8$M$_{odot}$ and SFR$sim$ 0.26 -- 2.6M$_{odot}$year$^{-1}$. The galaxy hosts a $sim$96kpc diffuse optical halo, which is unprecedented for spiral galaxies. We find that J1649+2635 resides in an overdense environment with a mass of M$_{dyn} = 7.7^{+7.9}_{-4.3} times 10^{13}$M$_{odot}$, likely a galaxy group below the detection threshold of the ROSAT All-Sky Survey. We suggest one possible scenario for the association of double-lobed radio emission from J1649+2635 is that the source may be similar to a Seyfert galaxy, located in a denser-than-normal environment. The study of spiral galaxies that host large-scale radio emission is important because although rare in the local Universe, these sources may be more common at high-redshifts.
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