Dr. Deva O'Neil
Dr. Charles Romero
Degree Award Date
Galaxy Cluster, Shocks, Noise
Applied Mathematics | Astrophysics and Astronomy | Physics | Statistics and Probability
We present pressure profiles of galaxy clusters determined by high resolution Sunyeav-Zel'dovich (SZ) observations from the MUSTANG-2 Bolometer on the Green Bank Telescope. We are particularly interested in studying the galaxy cluster RXJ 1347 that presents a cluster shock feature. We introduce a change in technique from previous papers where we no longer assume the noise to be independent. To account for this change, we look at the covariance matrix of a noise map for each cluster and implement that into our model. We take both of these models and construct non-parametric fits to create electron pressure profiles. This electron pressure was solved for in terms of the Compton parameter, y. We then looked at the change in electron pressure before and after the shock in order to calculate the Mach number. This tells us how quickly a portion of the cluster was moving. We did this with two different models for pressure profiles. One binned the map in terms of angle and radius, separating the shock from the rest of the cluster. The other model binned the map radially, but also fit for shape, taking into account the shock. We compared these results with each other and values from the literature and found a Mach number of 1.36 , which agrees with literature values.
Hancock, Daniel, "Pressure Profiles from Improved Noise Quantification" (2022). Honors Projects. 245.