The unusual slow cooling of hot carriers (HCs) in halide perovskites presents a promising route to harvest the excess carrier energy and exceed the Shockley-Queisser (SQ) efficiency limit of single-junction perovskite solar cells. Spectroscopic interrogation of HC dynamics is a crucial step toward an in-depth understanding of the HC properties and underlying cooling mechanisms in these materials. A range of spectroscopy techniques - most notably pump-probe (or transient absorption (TA)) spectros