A Candidate Dual AGN in a Double-peaked Emission-line Galaxy with
  Precessing Radio Jets
  We present high resolution radio continuum observations with the Karl G.
Jansky Very Large Array at 6, 8.5, 11.5 and 15 GHz of the double-peaked
emission-line galaxy 2MASXJ12032061+1319316. The radio emission has a prominent
S-shaped morphology with highly symmetric radio jets that extend over a
distance of $\sim1.5^{\prime\prime}$ (1.74~kpc) on either side of the core of
size $\sim0.1^{\prime\prime}$(116~pc). The radio jets have a helical structure
resembling the precessing jets in the galaxy NGC~326 which has confirmed dual
active galactic nuclei (AGN). The nuclear bulge velocity dispersion gives an
upper limit of $(1.56\pm$0.26$)\times$10$^8$~M$_{\odot}$ for the total mass of
nuclear black hole(s). We present a simple model of precessing jets in
2MASXJ1203 and find that the precession timescale is around 10$^5$ years: this
matches the source lifetime estimate via spectral aging. We find that the
expected super massive black hole (SMBH) separation corresponding to this
timescale is 0.02 pc. We used the double peaked emission lines in 2MASXJ1203 to
determine an orbital speed for a dual AGN system and the associated jet
precession timescale, which turns out to be more than the Hubble time, making
it unfeasible. We conclude that the S-shaped radio jets are due to jet
precession caused either by a binary/dual SMBH system, a single SMBH with a
tilted accretion disk or a dual AGN system where a close pass of the secondary
SMBH in the past has given rise to jet precession.
