A charged isolated air gap parallel plate capacitor of capacitance $2\mu F$ discharges with a time constant of $4\mu s$ upon introduction of a homogeneous dielectric material (dielectric constant = 2) in its gap. What would the time constant   (in multiples of  $\frac{1}{3}\mu s$) for the discharge be if the same capacitor not only has the above said dielectric but also a resistor of resistance $2\Omega$ connected across its plates?