Muon trace

November 4th was a great day for auroras, due to a G3 geomagnetic storm. I was at only 51 degrees latitude and at sea level, so no auroras, but I used my KP to shoot dark frames and, luckily, several particles interacted with the camera sensor during 4 minute exposures at ISO 100 (Bulb with Timed exposure). The KP was in the camera bag, lens cap on, and I controlled it with Image Sync from my smartphone. I did 5 exposures and in most of them I found some linear artefacts. Below is the longest trajectory I got. This should be the trace of a muon, a massive and short lived negatively charged particle arising when protons (cosmic rays) from the Sun collide with gas nuclei in Earth's upper atmosphere. It interacted with the surface of the KP sensor for about 212 pixels (824 microns) in length. There was no damage found afterwards (dead or stuck pixels).

100% crop, no levels adjustment, no noise reduction, straight from dcraw

tex wrote:

Actually, in the beginning it wasn't intentional. I was testing for something else. Then I got this and found several papers showing that muon trajectories can be captured by digital cameras.

After that I was tempted to try the same long exposures during a commercial flight, but I become worried by the prospect of producing dead pixels on the sensor. It seems that the single event burnouts that lead to dead pixels are dependent on the voltage applied to the semiconductor. I think there are higher chances of getting dead pixels if the camera is used when is exposed to more cosmic radiation (as at higher altitudes).

I read that most cameras on the ISS have a mean lifetime of 6 to 12 months, replaced when they accumulate too many dead pixels.

very interesting.  thanks for sharing.

Quite interesting . ` did not know anything about it . Thank you for the share .

Regards ,

mrp .

Yes! Your Pentax is a Cloud Chamber! Very fine.

Hi. I have learned a little about muons. May I ask why you have concluded it is a muon, as opposed a number other possibilities?

Thanks!

That's excellent and interesting, and a reminder that photography is about capture

candgpics wrote:

Hi. I have learned a little about muons. May I ask why you have concluded it is a muon, as opposed a number other possibilities?

Thanks!

Hi. I'm glad you found this interesting and thanks for the question. Muons are massive and have high speeds, meaning not easily disturbed from straight line trajectories. They are also charged, so can ionize the matter they traverse, hence the trace left on the sensor.

Further reading: patterns drawn by particles , classification of cosmic ray events captured by CMOS and CCD sensors , everything about muons

Thanks so much.

I am a hobbyist amateur astronomer and enjoy listening to lectures when I drive. I had heard about the muon time dilation experiment during physics lectures I listen to from time to time.

I live in Maine in the USA near Mt. Washington in NH where the below experiment took place in the 1960s.

https://www.youtube.com/watch?v=rbzt8gDSYIM

Interesting stuff!