The Dragonfly Edge-on Galaxies Survey: Shaping the outer disc of NGC 4565 via accretion

Understand

We present extremely deep imaging of the well-known edge-on galaxy NGC 4565 (the "Needle Galaxy"), observed as part of the Dragonfly Edge-on Galaxies Survey.

• Our imaging traces starlight over scales of ~100 kpc to surface brightnesses of ~32 mag/arcsec^2 in azimuthally averaged radial profiles.
• In narrow slice profiles along the major axis (with bin sizes ranging from 1.7 x 0.5 kpc to 1.7 x 7.8 kpc), we achieve a depth of ~29-30 mag/arcsec^2.
• We confirm the previously observed asymmetric disc truncation.