Stacking of Galaxy Spectra

This visualization, titled "Stacking of Galaxy Spectra" was submitted by Reagen Leimbach to the University of Arizona Libraries 2020 Data Visualization Challenge. It received the first place win within the undergraduate classification.

Submitted abstract:

This visualization demonstrates a critical step in my analysis using spectral data from a galaxy survey called “DEEP2”. In order to detect the [OIII]λ4363 weak emission line to diagnose gas properties in galaxies, spectra are combined together for average measurements. This technique called "stacking" reduces random fluctuations. Individual spectra (left) are stacked (middle) using an averaging approach, which produces the composite spectrum (right). This stack of ~ 80 spectra yields a strong [OIII]λ4363 detection. Stacking is the equivalent of observing a single rare galaxy in the early universe on a large telescope for over 80 hours.