1. Q-CUMBER Quality Control in Ultra coMpact Binaries by Examination of Research Jack Wright in the Armagh Observatory Introduction: A 'binary' is simply two stars orbiting each other around a central point. In order to qualify as an 'Ultra Compact Binary' the stars must complete one full orbit in about less than one hour, a very short time indeed! The fastest UCB has a period of only five minutes! Prior to my project beginning several images of the sky, or 'fields', had been taken by the Isaac Newton Telescope (seen at far right) in La Palma,. The purpose of this was to try and locate some of these elusive UCBs for study. The objective of my project was to search through the various identified sources in each of the 20+ fields to see if there were any UCB candidates and importantly, to remove any sources which are not real stars at all. The far-left graph shows a normal field. For a field to be 'good' each of the different coloured dots must follow the same pattern. The dots represent stars and the colours show the chip, the telescope is divided into four parts, each called a 'chip'. Unfortunately, I was unable to discern what may have caused this unusual chip behaviour during the project. Perhaps this discrepancy can be investigated in the future. Once all the fields were checked I moved onto check individual stars within them. Phase 1 Phase 2 Results & Conclusion & Acknowledgements: I found plenty of varying sources but of particular interest was the example above which has a period of about 2000 seconds and another potential UCB candidate with a period of 500 seconds, that's just over eight minutes! I believe my project was a complete success as I was able to give every available field an 'initial clean' and at the same time I have identified more than five possible UCBs. Finally, I would like to thank my mentor, Dr. Gavin Ramsay, and Tom Barclay, a PhD student working in the observatory. Both were invaluable to the success of my project and I owe them a great debt of gratitude for helping me complete it. When I was happy that a source was a genuine star I looked at its 'light curve' which shows how the brightness of the star varied with time. The one to the right shows a repeated dimming and brightening of the shown star. Here is an example of why 'quality-control' is needed. The software which extracts bright sources from the photographs taken by the telescope has identified this beautiful spiral galaxy as a star. Unfortunately it is not, therefore it had to be put to one side in the search for Ultra Compact Binaries... Spiral arms of galaxy clearly visible around bright centre. The graph to the immediate left shows a field which is 'bad'. The outlined outcrop of circled stars all belong to one chip showing that it may have malfunctioned in some way. Cross- examination with actual field shows only stars in the boxed area produced these anomalous results. Other Findings My first test was to see if each field's data were consistent. I did this by plotting various statistics in graphs and noted the shape of the generated graphs. Two examples of what I found are on the right. This is what the light-curve of a flaring star looks like. Flares can cause stars to more than double in brightness! Here is an eclipsing star which appears to become so dim it isn't doesn't seem to be detected for part of the exposure!