From the Fire: A Deeper Look at the Phoenix Stream

We use six years of data from the Dark Energy Survey to perform a detailed photometric characterization Phoenix stellar stream, 15-degree long, thin, dynamically cold, low-metallicity system in southern hemisphere. natural splines, non-parametric modeling technique, simultaneously fit stream track, width, and linear density. This updated model allows us improve measurements heliocentric distance ($17.4 \pm 0.1\,{\rm (stat.)} 0.8\,{\rm (sys.)}$ kpc) gradient ($-0.009 0.006$ kpc deg$^{-1}$) Phoenix, which corresponds small change $0.13 0.09$ along length stream. measure intensity variations on degree scales, as well deviations track $\sim 2$-degree suggesting that may have been disturbed during its formation and/or evolution. recover three peaks one gap with fluctuations track. Compared other thin streams, shows more and, consequently, study offers unique perspective gravitational perturbations streams. discuss possible sources including baryonic structures Galaxy dark matter subhalos.