Pico Tech • Beryllium Spectrums

Radiation Detection / Spectrum Examples ... Beryllium Links ... Beryllium Spectrum Change ... Reports From Mr Y ... Beryllium Hanahauok

Be-7 peaks. Totally natural?

I don't know if some of these peaks are totally natural.

According to the papers I've read;

Be-7 is usually formed in the upper atmosphere by interaction of high energy proton and N, C, O nuclei, and come down to surface in 7 days or so.
Be-7 correlates very well with the neutron presence at earth's surface.
Be-7 variation is about 3 times greater than the variation of neutron at surface.
Sun spot activity (or the lack of it) influences the variation of Be-7.
Rain, monsoon, latitude, etc influence Be-7 presence.
About 4 mBq/m3 average in the air (measured by dust sample) in 2010 to 2013. (From various CTBT reports)
Natural activity of 0.27 pCi/kg (0.01 Bq/kg). http://www.physics.isu.edu/radinf/natural.htm
(At least in some types of nuclear reactor) Be-7 is produced and present in coolant water.
Be-7 can be produced by the interaction of 14MeV neutron and Li-7 (which produces high energy proton that would interact with Li-7, again).

　　I've gathered some papers and other info in this page: Beryllium Links

If you have information about Be-7, please let me know

nkom (ATMARK) pico.dreamhosters.com

Japan

Yoneyama SA (Service Area = Parking/Rest area for highway) / Measured on 2013-4-20 (The sample taken before that date)
Clear enough Cs134, Cs137 peaks, but look at the Be-7 ! Comapre this spectrum with that of one month later: Beryllium Spectrum Change

It seems there is roughly double the amount of Cs137. So, it might be around 120 to 130 Bq/Kg (Just to give rough idea. To be verified)

Amagozen SA (Service Area = Parking/Rest area for highway)
Again, huge peak.

Peak is about 130 counts vs. 180 counts in the 1st sample. So, maybe 60 to 70 Bq/Kg (very rough guesstimate)

Akaiwa city
Not much Cs137/4, any more. But Be-7 is so big.

About the same count as the 1st one.

For more detail, you can see his entire report: http://pico.dreamhosters.com/img/Mr.Y/Moving-1.pdf

　　

See also　Beryllium Spectrum Change

Mysterious peak Be-7?

It's a spectrum of grass from a yard in Iwaki city, Fukushima (A little before 2013-02-10)

He sent it to a lb to be checked with HPGE detector, and they confirmed that it's Be-7

A chart of Be-7 variation in Fukushima

http://www.cnic.jp/4885

beryllium found on the soya leaves from Tochigi prefecture, Oct 2012.

http://www.cnic.jp/wp/wp-content/uploads/2012/12/0e49bb6f79a26d83332f00a55e2dac37.jpg

Dirt left after rain water has dried up, in Osaka, Japan. Taken around 2013-01, measured on 2013-06-28.

https://pbs.twimg.com/media/BOOl7l8CMAMy4if.jpg:large

A friend of this person living in Miyagi pref (next to Fukuchima) has wiped the guard rail at the road side, as they discovered high level contamination sticking to these things (and on the surface of transparent plastic sheet used for sun house at many farms). And tested with 1 inch NaI. He found Be-7 along with Cesium peaks (or more than cesium)

You can see more Beryllium7 spectrums in his twitter pages.
http://twilog.org/hanaharuok

https://pbs.twimg.com/media/BOBKk7ECcAEqyAB.jpg:large