Axel | Jan. 9, 2023, 10:24 a.m.

The Lyman Alpha Reference Sample (LARS) is a long running project aimed at studying Lyα at low redshifts to provide a reference atlas for details about Lyα emission. The observations for the project span many wavelengths between the Lyα to radio 21 cm.

The LARS uses a specially developed imaging technique to use the Hubble Space Telescope long-pass filters to image Lyα effectively at low-redshift. More than 13 papers have now been published using the sample to study many details of Lyα production and escape.

My participation in the LARS project has been primarily focused on studying the escape of Lyα from a multivariate point of view—trying to bring together the many measurements from the papers that came before it to see if we can predict the resulting Lyα emission. Essentially we want to see if we can overcome the scatter that is ubiquitous in all Lyα correlation studies by looking at more than one variable at a time.

We find that the scatter can indeed be reduced and we are able to explain of the order of 95% of the variance in Lyα luminosity. However, we do find that the escape fraction and equivalent width are more difficult to predict.