Red faces abound as boffins build gamma ray lens
Scientists have disproved a chunk of theoretical physics by building a series of lenses capable of focusing gamma rays. A team at the Institut Laue-Langevin (ILL) research center used twin silicon wafers to bend a stream of gamma rays, something that had been thought to be impossible. The team posits, in an article in the …
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I just got an image
of a wild-haired mad scientist type twiddling knobs on a large machine, with gauges and dials wildly fluctuating, to the sound of great dynamos winding up, all bathed in a pulsating green glow.
"Power", he cries, "we must boost the power!"
Re: I just got an image
But, massster! We are already at 500 MeV per quantum! No, not that button, master. NO!!
Re: I just got an image
Not forgetting the essential Jacob's ladder, knife switches and brain in a tank.
"Quickly Igor, while the storm is at its height!"
Re: I just got an image
Morbius from "Forbidden Planet" managed to get "the number 10 raised almost literally to the power of infinity". So no worries!
Re: I just got an image
Because that number is so much bigger than infinity!
death ray
Yayyyy I will get that death ray I wanted for christmas 1987!
More than 20years ago
> "20 years ago many people doubted you could do optics with x-rays – no one even considered that it might be possible for gamma-rays too
Hang on, it has to be nearer 30 years ago I went to lecture at the RI where an engineer from IBM was talking about their "lens" for focussing X-Ray for fine line lithography. At the time most silicon processes were moving from 5u to 3.5u but they liked to plan ahead, and that was certainly the level we were fabbing.
If I remember correctly they were old gold Fresnel lens back then.
Re: More than 20years ago
"Old gold Fresnel lens" - was that a Van der Graaf Generator side project?
You are right, and not just X-rays but low gamma more than 20years ago
The Fresnel-type lenses in question even made it to the mainstream scientific press. To do gamma rays they had to make what amounted to series of nested lenses whose depth was greater than the diameter.
With the diagrams I recall, there was an outermost lens shaped rather like a long curved plant pot, with an internal coating of metal. The next one in was a similar shape but slightly smaller, and so forth till reaching a central spindle. An incoming X or gamma ray would graze the metal coating at a very low angle of incidence, so low that total internal reflection propagated the wave straight through a gentle curve to the exit.
Of course the mirrors in question only had Fresnel resolution, but that could be very high.
Re: You are right, and not just X-rays but low gamma more than 20years ago
Not Fresnel lenses - they used a nested set of glancing incidence mirrors
The problem is that only a tiny region near the mirror has the correct angles for glancing incidence - so you make a mirror 1m diameter and you only get to use a few micron wide ring around it. So you have to stack lots of them like tubes and because the wavelength is so small they have to be polished to fantastic tolerances
They're called Wolter mirrors http://www.x-ray-optics.com/index.php?option=com_content&view=article&id=59&Itemid=71&lang=en#Wolter_optics
Re: More than 20years ago
I remember 15 years ago you could buy russian made x-ray lenses quite cheaply too. But these are gamma rays and I cannot remember there was anything available back then (since I've left the field).
Re: Paging David Banner
I think you mean "Bruce Banner".
And that's DOCTOR Bruce Banner to you - he gets angry when people forget the Doctor!
(For some reason, when they did the Bill Bixby/Lou Ferrigno TV show, they decided "Bruce" wasn't butch enough, and went with David - don't ask me why)
Re: Paging David Banner
Hulk like new lenses, Hulk see good now!
Re: Paging David Banner
Somehow that puts me in mind of the Candygram and someone punching a horse.
Re: Paging David Banner
As a kid I always thought they were calling him "David Banning" and that he was operating under the crappest, most transparent pseudonym ever...
Re: Paging David Banner
"...they decided "Bruce" wasn't butch enough, and went with David..."
Or maybe they didn't like Stan Lee's double initial fetish.
Re: Paging David Banner
Then why hire Bill Bixby for the part? :o/
Re: Paging David Banner
Alliterated naming convention fetish.
Re: Next step...
Wouldn't that be a gaser cannon?
Has some hilarious comedy potential right there.
Homeland Security
Homeland Security would think its a good idea to use gamma rays to scan airline passengers.
Re: Homeland Security
Forget that, far better to scan the entire plane, from the ground, before it lands in order to detect all bottles of liquid capable of containing more than 100ml.
hulk SMASH puny lens
happen three times this week
hulk go see eye doctor again
hulk still not meet deductible
Researchers...
"This is a remarkable and completely unexpected discovery...". So, you weren't trying for it? Or you just expected to fail and were just spending a research grant? Or you just came across this by accident while you were doing something unrelated with gama rays, complex lenses etc.
Just wondering
Re: Researchers...
Give them some credit. Some of the very best discoveries come about when people say "Well, I don't expect it'll work but it's the best idea I've got and if it does work the implications are enormous".
Your comment suggests a complete ignorance of the motivation for, and methodology behind, a large proportion of all useful scientific research. I, on the other hand, spent an entire year firing lasers at a solution of fairy liquid in a futile attempt to develop a new spectroscopic technique. It was the best idea I had at the time and I didn't get paid a fucking penny for it.
Just saying.
Re: Researchers...
"completely unexpected"
It seems they were just sweeping up after a particularly unsuccessful party, when the idea struck them. It also involved a really hot cup of tea.
I just hope they are looking out for mobs of respectable scientists carrying flaming torches and pitchforks.
With apologies to Douglas Adams.
Re: Researchers...
Sounds like a classic "That's funny..." moment, to me.
If you're doing something that involves using machined chunks of silicon in the path of gamma rays for some other reason entirely (perhaps they're to neutrally mount some other material that you're irradiating), and then you find that your gamma ray detector isn't getting any rays.... after uttering the words above, you mess around with the layout and discover that removing the silicon sorts it. Rather than going "phew" and carrying on with the original experiment, you say "that's very funny..." So you put the silicon back, move the detector around, move the silicon around, discover silicon refracts the gamma rays. "Eureka!" follows.
Science happens like that all the time, the serendipitous surprise is a major component of the fun. As are the celebratory beers.
Re: Researchers...
But your research might have been one of those 'happy accidents' that actually developed an alternative to leaving the hot tap running.
(as a means to stopping the washing-up water getting cold.)
Re: Researchers...
Oh, Edmund... can it be true? That I hold here, in my mortal hand, a nugget of purest Green?
Theoretical physics?
Doubtful. Engineering assumptions more likely.
New physics?
There's a more detailed report here:
http://physicsworld.com/cws/article/news/2012/may/09/silicon-prism-bends-gamma-rays
which goes a bit further in explaining what they were doing, why they were doing it, and how what they found deviated from previous theoretical predictions.
But I suspect that most undergraduate level physics textbooks can stay on the shelves for the time being.
Many great discoveriers are
made by young people without enough experience to know that what they are trying is known to be impossible. And because they don't know its impossible they find that they can do it.
Eh?
Can someone translate this into understandableish:-
"ESA researchers estimate that a one million second point source observation at 511 keV using a gamma lens would be 100 times as effective as current research techniques."
Re: Eh?
Boffins from the Euroverse space agency estimate that if they can point an telescope with a gamma ray lens at someplace like Centaurus-A, say, for about twelve days straight, and all the while capture harder gamma rays than they can currently observe with their old kit, they'd detect a hundred times more than they do now.
Overstandable enough?
[Earlier post replaced 'cause I couldn't remember Centaurus from Cygnus]
And there I was hoping they had generated a space-time distortion which acted as a lens.
... the problem with that is a massive body would be required (gravitational lensing).... like ... yo momma? (couldn't resit)
"tools to address major national security issues."
In other words, "Hulk, smash!"
moore's law
Does this mean we get to tack another 10 years onto Moore's law (by letting the process boffins roll out gamma ray lithography over the next 20 years?).
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