You are warmly invited to attend a Colloquium by Dr. Ayodeji. Dr. Ayodeji presently serves as an ANSO fellow (postdoctoral scholar) at the National Astronomical Observatories, Chinese Academy of Sciences in Beijing. Previously, he successfully completed his PhD in Cosmology at the University of KwaZulu Natal, South Africa in May 2021. His academic journey includes achieving an MSc in Theoretical Physics from the University of Ibadan, Nigeria, and a BSc (First Class) in Physics from Obafemi Awolowo University, Nigeria.
Dr. Ayodeji's research is centered on the cosmological exploration of various large-scale structure observables, with a special focus on 21cm cosmology. His aim is to deepen our understanding of the formation and evolution of cosmic structures in the Universe.
Title: Cross-correlations between the thermal Sunyeav-Zel'dovich effect and large-scale structure tracers: towards improved cosmological constraints.
Abstract:
In the era of precision cosmology, observational data are being used to place constraints on cosmological models. One of the versatile methods employed for this purpose is the cross-correlation of cosmic tracers.
The thermal Sunyaev-Zeldovich (tSZ) effect is a secondary anisotropy of the cosmic microwave background (CMB) radiation caused by the inverse Compton scattering of CMB photons off warm-hot electrons. The tSZ amplitude is set by the Compton parameter y which is proportional to the electron pressure integrated along the line-of-sight (LoS). The tSZ effect is independent of the observing frequency (it is not explicitly dependent on redshift) which makes it a useful large-scale structure (LSS) tracer. This implies that all of the warm-hot gas encountered by CMB photons from the last-scattering surface up to the observer contributes to the spectral distortion. In this context, cross correlating the observed tSZ with other LSS tracers is a very useful tool to recover information on the redshift of the responsible hot gas; this, in turn, allows for a better characterization of the diffuse gas component distribution in relation with the cosmic web, eventually providing insights into the growth of structures and other fundamental cosmological parameters.
"In this talk, I will take you through the journey I started in my PhD on how I have combined the tSZ probe with other large-scale structure tracers to answer the missing baryon problem, study the distribution of neutral and ionized gas, understand the process of galaxy evolution and probe fundamental cosmological parameters. In the end I will discuss potential projects to use observational data to constrain F(T), F(Q) and GR parameters."
For more information, kindly contact Prof Amare Abebe.