Kathy Romer

Galaxy clusters

Clusters of galaxies as cosmological probes and astrophysical laboratories: making use of the latest X-ray and optical surveys

 Supervisor: Dr A. Kathy Romer  (in collaboration with the XMM Cluster Survey and Dark Energy Survey international consortia)

Abstract: Clusters of galaxies offer a unique window on the universe. As the largest collapsed objects in the heavens, they can be used to probe cosmology in a variety of ways. Moreover, they are host to a range of complex astrophysical processes and hold the key to unlocking mysteries such as the evolution of galaxies. The XMM Cluster Survey (XCS) is an international, Sussex led, project (~20 scientists) that has uncovered more X-ray bright clusters than any other survey before it. This world leading project is ripe for scientific exploitation, with thousands of clusters available for individual or ensemble analysis. The ultimate goal of the XCS is to constrain models of Dark Energy, but a student would be able to choose from a variety of different science and analysis applications. The student would also be able to take part in the much larger (~500 scientists) Dark Energy Project - an optical project that has to detected 100 times more clusters than XCS using the signature of galaxy over density. The student would have the opportunity to work on XCS projects that have DES applications. They will also have the opportunity to get involved in several upcoming international projects (LSST, Euclid, Athena, 4MOST etc.).

Skill development: the student will acquire generic research skills (literature searching, oral presentations, document preparation, setting/meeting goals etc.) through on the job training and through the specialist skills courses available through the University. The student will develop generic astronomy skills (programming, use of astronomy archives, use of astronomy tools, proposal writing, optical observing, complex statistic analysis and data modelling etc.) through on the job training and courses offered in the department. The student will also develop, through mentorship from the supervisors and from self learning, several specialist astronomy skills that will be desirable to future postdoc employers in areas of observational cosmology and/or extragalactic astronomy. These specialist skills will depend somewhat on the choice of project, but might well include X-ray or optical spectroscopy, X-ray or optical image analysis, parallel programming, source detection, multi-wavelength studies, deep (machine) learning, and anomaly detection.

Opportunities for travel: students will have the opportunity to take part in XCS and DES related observing campaigns, even if the resulting data is not integral to their thesis. Students will be encouraged to take part in consortia meetings, e.g. recent DES meetings have been in USA and Spain. Students will take part in XCS meetings and in collaborative visits to XCS members. XCS members are scattered across the UK and Europe, and as far afield as USA, Chile, South Africa. In addition to research related travel, Students will take part in several UK conferences; at least one International Summer Schools; and at least one international conference.

Watch a video of Kathy and her former (STFC) student, Leon Baruah, talk about their cluster research for the Dark Energy Survey