Multiband Imaging of the HD 36546 Debris Disk: a Refined View from SCExAO/CHARIS

We present the first multiwavelength (near-infrared; 1.1-2.4 mu m) imaging of HD 36546's debris disk, using the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) system coupled with the Coronagraphic High Angular Resolution Imaging Spectrograph (CHARIS). As a 3-10 Myr old star, HD 36546 presents a rare opportunity to study a debris disk at very early stages. SCExAO/CHARIS imagery resolves the disk over angular separations of rho similar to 0.'' 25-1.'' 0 (projected separations of r(proj) similar to 25-101 au) and enables the first spectrophotometric analysis of the disk. The disk's brightness appears symmetric between its eastern and western extents, and it exhibits slightly blue near-infrared colors on average (e.g., J-K = -0.4 +/- 0.1)-suggesting copious submicron-sized or highly porous grains. Through detailed modeling adopting a Hong scattering phase function (SPF), instead of the more common Henyey-Greenstein function, and using the differential evolution optimization algorithm, we provide an updated schematic of HD 36546's disk. The disk has a shallow radial dust density profile (alpha (in) approximate to 1.0 and alpha (out) approximate to -1.5), a fiducial radius of r (0) approximate to 82.7 au, an inclination of i approximate to 79.degrees 1, and a position angle of PA approximate to 80.degrees 1. Through spine tracing, we find a spine that is consistent with our modeling, but also with a "swept-back wing" geometry. Finally, we provide constraints on companions, including limiting a companion responsible for a marginal Hipparcos-Gaia acceleration to a projected separation of less than or similar to 0.'' 2 and to a minimum mass of less than or similar to 11 M (Jup).