1. HiSparc How air pressure, affects the amount of high energy particles reaching the earths surface. By Ollie Fazakerley

2. Data used and how it was collated All data used was from the Nikhef detector, during January 2013. I choose to use this site as they have 4 detectors and a barometer. I developed I simple macro in excel, which converted the time from seconds after 1/1/1970, to time in hours that day and took an average of all the air pressure readings, for each hour of the day.

4. What the data shows When there is a change of 10hPa, the trend line shows that on average, you get a 5.8% decrease in the number of coincidences per hour. The lowest pressure recorded during Jan 2013 was 986hPa, which would occur during a storm and the highest 1023hPa, which could occur in a period with very little cloud cover. The trend shows that you would get a 21% difference in the amount of particle coincidences per hour, between these two extremes. The most obvious explanation would be that in periods of high air pressure, there is a greater concentration of air particles, so more high energy particles are absorbed by air particles, meaning less reach the earths surface.

5. What could this data ne used for? Air pressure readings, could be taken into account when investigating how other factors affect the amount of high energy particles reaching the earths surface. This would make the investigation more reliable, as the there are less external factors, that are unaccounted for, affecting the results.