  We present deep imaging observations, orbital dynamics, and dust tail model
analyses of the double-component asteroid P/2016 J1 (J1-A and J1-B). The
observations were acquired at the Gran Telescopio Canarias (GTC) and the
Canada-France-Hawaii Telescope (CFHT) from mid March to late July, 2016. A
statistical analysis of backward-in-time integrations of the orbits of a large
sample of clone objects of P/2016 J1-A and J1-B shows that the minimum
separation between them occurred most likely $\sim$2300 days prior to the
current perihelion passage, i.e., during the previous orbit near perihelion.
This closest approach was probably linked to a fragmentation event of their
parent body. Monte Carlo dust tail models show that those two components became
active simultaneously $\sim$250 days before the current perihelion, with
comparable maximum loss rates of $\sim$0.7 kg s$^{-1}$ and $\sim$0.5 kg
s$^{-1}$, and total ejected masses of 8$\times$10$^{6}$ kg and
6$\times$10$^{6}$ kg for fragments J1-A and J1-B, respectively. In consequence,
the fragmentation event and the present dust activity are unrelated. The
simultaneous activation times of the two components and the fact that the
activity lasted 6 to 9 months or longer, strongly indicate ice sublimation as
the most likely mechanism involved in the dust emission process.
