H0LiCOW VIII. A weak lensing measurement of the external convergence in the field of the lensed quasar HE$,$0435$-$1223

We present a weak gravitational lensing measurement of the external convergence along the line of sight to the quadruply lensed quasar HE$,$0435$-$1223. Using deep r-band images from Subaru-Suprime-Cam we observe galaxies down to a 3$sigma$ limiting magnitude of $sim 26$ mags resulting in a source galaxy density of 14 galaxies / arcmin$^2$ after redshift-based cuts. Using an inpainting technique and Multi-Scale Entropy filtering algorithm, we find that the region in close proximity to the lens has an estimated external convergence of $kappa=-0.012^{+0.020}_{-0.013}$ and is hence marginally under-dense. We also rule out the presence of any halo with a mass greater than $M_{rm vir}=1.6times10^{14}h^{-1}M_odot$ (68$%$ confidence limit). Our results, consistent with previous studies of this lens, confirm that the intervening mass along the line of sight to HE$,$0435$-$1223 does not affect significantly the cosmological results inferred from the time delay measurements of that specific object.