Cluster Connectivity Intern Petras interviewed early-career summer researchers about their projects and personal motivations

Interviewed by Petras Verseckas (Cluster Connectivity Intern). Edited by Becky Ball (Cluster Connectivity Intern), Christina MacLeod (Cluster Development Project Manager), and Dr. Hina Khan (Executive Director). Interviews were conducted on the 26th of July, 2024, and published on the 12th of August, 2024.

Sophia Tonelli (s.tonelli@sms.ed.ac.uk) and Hanna Golawska (h.golawska@sms.ed.ac.uk) are both students at the University of Edinburgh entering their fourth year of undergraduate studies in Astrophysics. Space Scotland SPINterns sat down to chat with them after they completed their end-of-project presentations to staff at the Observatory.

Hanna

Abstract: The James Webb Space Telescope (JWST) offers unparalleled capabilities for observing the most distant objects in the universe, allowing us to look back in time and study galaxies formed just after the Big Bang. Using the latest imaging from the PANORAMIC survey, which covers an exceptionally large area of the sky, I applied the Lyman-break technique and spectral energy distribution fitting to identify 26 galaxy candidates at redshifts greater than 9.5, including two around redshift 14.5. These findings are significant as the current record for the most distant spectroscopically confirmed galaxy stands at redshift 14.32. Some of these galaxies are likely to be confirmed spectroscopically in Cycle 4 of JWST observations. My results, including the derived UV luminosity function at redshift 14.5, are consistent with existing literature.

Interview

Hanna Golawska is entering her fourth year of undergraduate studies in Astrophysics at the University of Edinburgh. This summer, she spent a couple of months at the Royal Observatory Edinburgh (ROE) looking for the highest redshift galaxies from the James Webb Space Telescope (JWST) images supervised by Dr. McLeold.

She has improved her programming skills while working on the project. While debugging code errors can be tedious (something lots of us can relate to!), she found it very rewarding to work with the computer cluster at the ROE facilities. She is hopeful she can apply the skills she has acquired in the future. It was special to work on the JWST images during her time at the Observatory as she had been following the project since before it took to the skies.  Reflecting on the first JWST images released, Hanna feels honoured to have worked on the telescope’s images so early in her career. “It is special to have worked with an institution that had a lasting contribution to the construction of the telescope”, she says.

Hanna contrasted detected galaxy spectra to simulations of thousands of other galaxy spectra to find the best fit. When asked how she could extend her research, she replied that for the results to be more robust, comparisons should also be made to stellar spectra (to rule out star detections, which she admits is a possibility). As the code runs for hours, generating libraries for thousands and possibly millions of spectra, there was little time to do this, but she says it would be an interesting next step. ‘Completeness simulations’ involve introducing digital, artificial galaxies that fall into the redshift range investigated and using new images to treat them with the same Python analysis pipeline. This analysis determines how many could be recovered (it won’t be 100%, she chuckles) but would help evaluate the efficacy of her models.

Finally, she’s interested in determining the stellar formation rate density which she explains is an integral of the luminosity function. This appears to be a simple calculation that acts as a tool to pinpoint when galaxies began forming, when stars started forming within them, and when these first stars ignited. It would show whether these cosmic phenomena started at the redshift she had spent time investigating. It sounds simple, she says – all it takes is integrating a single data set or function - but it quickly becomes more complex.

Her interests lie in contributing to JWST’s successor in her lifetime. A member of the university rocketry team – she speaks fondly about taking part in the design and construction of body tubes ensuring rockets are structurally sound. She’s set to join next year’s payload team where she hopes to contribute to designing the science mission on board. Her team’s liftoff is set for later this year along with plenty of exciting developments in the Scottish mega-cluster!

Sophia

Project scope: The Role of AGN Jet Feedback Parameters on X-ray Cavities in the Intra-cluster Medium.

Interview

Sophia Tonelli is entering her fourth year of undergraduate studies in Astrophysics at the University of Edinburgh. She spent the summer months at the Royal Observatory, Edinburgh (ROE) investigating the role of Active Galactic Nuclei (AGN) Jet parameters on x-ray cavities in the inter-cluster medium (ICM). She has been able to pursue her interest in computational approaches to theoretical physics in addition to training in telescope observations. Fascination in cosmological observations led to Sophia’s interest in using computational simulations to guide real world analysis.  

While her focus revolved around investigating enthalpy – the heat content of x-ray cavities – she stumbled into entropy (uncertainty’s) role on them. It is a tricky concept in physics and the universe, she says, but her interest led her to start investigating the thermodynamic profile of the entropy of black holes. She hopes to explore the effect of AGNs on the ICM with regards to entropy’s influence. Sophia’s focus on theoretical physics paved the way to her looking into the thermodynamics of ‘bubbles’ and ‘jets’. 

She is interested in continuing work investigating the role of AGN in the ICM. This research can predict and see how AGNs with Jet emissions can slow galaxy motion and prevent the cluster from becoming overpopulated with galaxies – poetically helping maintain a balance in the universe. The project can be useful in predicting galaxy evolution that slows depending on AGN presences as well as determining whether new galaxies are forming as AGN release specific heat amounts. She is hopeful that improving computer simulations in radioastronomy can help better guide the Chandra telescope to better detect the cavities by predicting the heat released into the ICM and its resultant impact. She foresees applications in the future of x-ray astronomy. 

Nuclear fusion is a particular interest of Sophia’s as she explores intersections between processes within stars (nucleosynthesis) and the use of this knowledge on Earth. Part of the sustainability society at the university – she presented a talk comparing the processes in stars and nuclear processes on Earth. The Joint European Torus (JET) famously houses some of the coldest and hottest places on Earth mere metres away from each other allowing for the heating and cooling of magnetically confined plasma physics experiments. Further merging sustainability and space interests, she is already author of a paper about active debris removal and would like to contribute to renewable energy generation in space. She also finds time to engage with the philosophical dimensions of her work and thinks that the physics discipline should engage more with the existential questions as our generation’s space race soars.