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Thanks blam. |
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Posted on 01/21/2013 7:50:06 AM PST by blam
Did An 8th Century Gamma Ray Burst Irradiate Earth?
Science Daily
January 21,2013
A nearby short duration gamma-ray burst may be the cause of an intense blast of high-energy radiation that hit the Earth in the 8th century, according to new research led by astronomers Valeri Hambaryan and Ralph Neuhӓuser.
The two scientists, based at the Astrophysics Institute of the University of Jena in Germany, publish their results in the journal Monthly Notices of the Royal Astronomical Society.
In 2012 scientist Fusa Miyake announced the detection of high levels of the isotope Carbon-14 and Beryllium-10 in tree rings formed in 775 CE, suggesting that a burst of radiation struck the Earth in the year 774 or 775. Carbon-14 and Beryllium-10 form when radiation from space collides with nitrogen atoms, which then decay to these heavier forms of carbon and beryllium. The earlier research ruled out the nearby explosion of a massive star (a supernova) as nothing was recorded in observations at the time and no remnant has been found.
(snip)
(Excerpt) Read more at sciencedaily.com ...
Also called spallation. I have seen spallation at the HERMESIII accelerator, but usually with a high-Z target. Not much from Al, plenty from W.
It’s a possibility to get n from high energy photons, but the lower the Z, the smaller the cross section.
I kind of like the suggestion that it was Viking nukes! Or maybe a “natural reactor” like at Gabon that has not been discovered yet.
[[Did An 8th Century Gamma Ray Burst Irradiate Earth?]]
After wtinessign the left in action for decades, does this question really need to be posed?
yup...These threads (and the space/science threads) used to be fantastic on FR. These days, only the wannabe comediennes show up with the same tired posts.
I think more samples from a wider spatially distributed tree sampling is in order before thinking that the sky is falling and we're all going to die (maybe).
Damned Zenu.
I don’t know enough about this kind of science to completely understand how nitrogen plus gamma rays gives you carbon and berryllium. I’m guessing that you get a nitrogen isotope that decays into Carbon 14 which then (or another carbon isotope) decays into berryllium and an alpha particle. I’m sure I’m way off.
Any experts out there?
That is only the increase in Carbon 14
Beryllium -10 is radioactive with half life of over
1 million years, it would be found by examining ice cores
and picking up the increase in Be-10 for that time
I was kind of shocked, too. Schools just aren't providing an education in the classics anymore.
To answer part of my own question:
14N7 + n = 14C6 + p
(according to wikipedia)
This event is preserved in the Italian oral tradition known as
THE BADA BADA BING.
LOL
“If its not one thing its something else” Rozanne Rozannadana
Mysterious radiation burst recorded in tree rings
Nature | Sunday, June 3, 2012 | Richard A. Lovett
Posted on Mon Jun 4 13:58:45 2012 by SunkenCiv
http://www.freerepublic.com/focus/chat/2891403/posts
The Cosmic Story of Carbon-14
Starts with a Bang | 6/4/12 | Ethan Siegel
Posted on Tue Jun 5 03:48:06 2012 by LibWhacker
http://www.freerepublic.com/focus/chat/2891641/posts
http://www.osti.gov/bridge/servlets/purl/7316590-E86RO8/7316590.pdf
The overall cross section for N14 is about 96 mb, but the threshold is pretty high, 24 MeV.
I guess a gamma ray pulse could do it, but at 24 MeV those photons would penetrate pretty deep, the primaries and secondaries would dose up the surface, I think.
I don’t have access to MCNP right now, that would give a clue.
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| GGG managers are SunkenCiv, StayAt HomeMother & Ernest_at_the_Beach | |
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Thanks blam. |
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The Cycle of Cosmic Catastrophes:
Flood, Fire, and Famine
in the History of Civilization
by Richard Firestone,
Allen West, and
Simon Warwick-Smith
I like the idea of Viking Nukes! LOL!
closely related:
Researcher points to Sun as likely source of eighth-century ‘Charlemagne event’
PhysOrg | 11-20-2012
Posted on Wed Dec 12 08:34:52 2012 by Renfield
http://www.freerepublic.com/focus/chat/2967972/posts
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