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Origin of Cosmic Rays Confirmed
cats-paw writes in with news of research that seems to confirm and support current theories of how cosmic rays are created. The prevailing thinking has been that cosmic rays are generated in the regions where supernovas' shock waves interact with the interstellar medium. The new research used the variability in X-ray emissions from a supernova remnant to estimate the strength of the magnetic fields present in that environment. The results lend support to the possibility of protons and nucleii being accelerated in supernova remnants to energies of 1 PeV (10^15 eV) and beyond. Here is the abstract from Nature.
The Cosmos
research that seems to confirm and support current theories of how cosmic rays are created.
Oh, great, now that everyone knows how to make them, the Fantastic Four are going to be up to their eyeballs in supervillainry.
The theory of relativity doesn't work right in Arkansas.
It comes back with .00160217 joules. Isn't this a very small amount of energy, or am I missing something?
I've read Slashdot for the last 5 years, and now I start posting... Go figure
So this research confirms... supports...well lends support to the possibility. Care to soften it further?
they are created when God puts foil in his microwave :P
Monstar L
Give credit to cats-paw for giving us the link to the abstract for the original paper and to the editors for putting this up rather than a link to some half-baked pseudo-science blog about it.
I think if I was not an experimentalist, I would want to study this area of physics (supernova observation). Going through the steps of a supernova exposes you to some of the most amazing physics we know of, and this research only adds to that.
Stop trying to sound "smart" by ending words with "ii". To make Latin words ending "us" plural, remove the "us" and add ONLY ONE "i".
"nucleus" -> "nuclei"
"radius" -> "radii" (because there's already an "i" before the "us")
I think "Cosmic Ray's" would be a great name for a futuristic bar. That, or the "Space Bar".
Knowing Google's lust for data collection, the Soviet Union is still alive and well inside the psyche of Sergey Brin....
Thats almost 6,500,000,000,000,000,000 degrees!!!!
Additionally, the abstract says their research "provide[s] a strong argument" for a theory. I suppose these statements are way too hard-line for Real Science. Sheesh. These are people who know very well they're doing inference rather than deduction - including the submitter! - and you take them to task for jumping to conclusions.
You say:
The hypothesize/predict/experiment cycle isn't nearly as boolean as you make it out, even though we teach it that way in school.
If a result doesn't disprove a theory, it actually increases its probability among other possibilities. Bayesian statistics models this quite well, and scientists think about it that way but without such a rigorous foundation. For example, in all forces, we've measured the differential relationships among position, velocity and acceleration to ridiculous precision. Doesn't this increase the probability that we've got it right? In this area, if there's a conflict between predicted and expected outcomes, we regard the explanation that the theory is wrong as the less probable one - much less probable.
Part of the problem is classical statistics. Null hypotheses and tests against them are kludgy nonsense, everyone knows it, and everyone has their own way of doing it "properly". (Think about it this way: Pr(null hypothesis), where the null hypothesis has a continuous component - and this is done all the time - is ZERO.) Doing inference without priors is a misguided attempt at objectivity. These mindsets are well-preserved in scientific philosophy, and they've got to go. Nobody actually thinks about real inference the classical way. It'd be ridiculous to try it on any hypothesis of moderate complexity.
I got my Linux laptop at System76.
First of all, the summary (but also the article) refer to "cosmic rays", as if they are all the same. Most, actually, come from the sun. The nature abstract talks about "galactic cosmic rays", which better, but there are thought to be many flavors of these as well, as there are many ways to accelerate charged partcles.
The poster child of uber-freaked out cosmic rays is a crazy bugger detected in 1991 that had an energy of 3.2 x 10^20 eV. One scientist compared it to dropping a brick on your toe! Cosmic rays with this much energy are too enegetic to fit the supernova shock wave model nicely. They might come from gamma ray bursts or black holes on a feeding frenzy.
Those people who think they know everything are a great annoyance to those of us who do. (Isaac Asimov)
But how many Libraries Of Congress On Fire is that?
No No No No No
No No No No No No No
No No No... Maybe
that's no galaxy
...Also known as 6 quintillion, 446 quadrillion, 700 trillion.
While we're at it, a million millions is one trillion.
No offense, but geez, call it what it is.
how is babby formed?
So, if I need to cook a turkey, how long should I leave it in at 6,446,700,000,000,000,000 degrees?
"It is our blasphemy which has made us great, and will sustain us, and which the gods secretly admire in us." - Zelazny
42
Of course, at this energy the impact of the proton with the lead would result in a lot of neutrons being released, and lead doesn't stop those very well. Maybe if you made some sort of composite-sandwich with lead followed by neutron moderating material and a neutron absorber. Of course, then the neutron-activation of the absorber would cause gamma-ray emissions, so you'd need another layer of lead, possibly followed by another neutron absorber. So, well, you might need something like lead-carbon-cadmium-lead-carbon-cadmium-lead lined underwear. Dry cleaning only, keep out of reach of children.
Interestingly, there's about the same energy density in a cc of space from cosmic rays as there is from starlight. The difference is that photons travel straight so you see the stars as points of light, cosmic rays get all scrambled from the magnetic field so things would appear hazy.
But Olber's paradox says that if the universe were infinitely large and infinitely old, then no matter where you looked you'd eventually see the surface of a star, so the sky wouldn't just be bright: it would be be sun-bright, rather than just faintly hazy.