Cosmic Ray Detections with CCD Cameras

(supervisor: Tony Cook)

Nature of project: experimental, data analysis

Available to full-time physicists only.

Project description and methodology

Charge Coupled Devices (CCD) can detect the ionizing effects of cosmic ray particle decay as well as natural background radiation levels. One of the reasons why CCD cameras end up with "dead pixels" or "hot pixels" is because the pixels can end up being damaged by extremely energetic particles. Cosmic ray decay particles can also cause computers to crash occasionally, simply by charge dumping in critical logic areas of computer memory, or on data buses. This project will involve taking hours of video using CCD cameras (or possibly web cameras) in a dark environment. The video frames will then be examined with existing off the shelf software, in order to detect the brief flashes from the cosmic rays decay particles.

A successful project will develop beyond the above in one/some of the following directions:
1) The frequency of cosmic ray events detected should be checked against time of day, and orientation of the camera.

2)Investigate different types of cameras to see how their sensitivity to cosmic ray air showers varies

3) Can you classify cosmic ray decay particles, present in images, by the shape of the flash, strength of the detection, or other characteristics?

4) Do magnets placed near to the camera cause the particles to be deflected? What does this tell you?

When considering where to take your project, please bear in mind the time available. It is preferable to do fewer things well than to try many and not get conclusive results on any of them. However, sometimes it is useful to have a couple of strands of investigation in parallel to work on in case delays occur.

Additional scope or challenge if taken as a Year-4 project: 1) Compare CCD detections to simultaneous Geiger counter detections

2) What are the merits of short or very long exposures in CCD cosmic ray air shower detections?

3) Place two cameras in parallel to see if you can find the 3D track of

particles through the image planes

Initial literature for students:

  1. Groom, D. (1998) Cosmic Rays and other Nonsense in Astronomical CCD Imagers, http://snap.lbl.gov/ccdweb/groom.pdf
  2. Ziegler, J.F. (1996) Terrestrial Cosmic Rays, IBM Journal of Research and Development, 40, p19-39.
  3. Hill, R., Landsman, W., et. al. (1997). Cosmic Ray and Hot Pixel Removal from STIS CCD Images. HST Calibration Workshop. Space Telescope Science Institute. Johns Hopkins University. ARUA. NASA.
  4. Linsley J. (1963). Phys Rev Letters. Vol. 10 p. 146 Referenced by A. Watson, A. (2002). Extensive Air Showers and Ultra High Energy Cosmic Rays. Department of Physics and Astronomy. University of Leeds

Novelty, degree of difficulty and amount of assistance required

It will be relatively easy to capture video with a camera(s) in a light tight environment. Looking for trends will be more problematic as the count rate is low i.e. 1 per minute(s). Assistance will be given to train the student in the use of CCD cameras, video software and flash detection software.

Project milestones and deliverables (including timescale)

milestoneto be completed by
Decide upon equipment needed and specifically what you will investigate during the experimentsChristmas
How do detection rates vary with time of day and orientation of camera(s)?end of February
Statistical study of the types of cosmic ray detections in the cameramid-March
Do magnets have an effect on the air shower particles?Easter

Students taking this project will have to submit a full risk assessment form