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Record-Setting 100+ T Magnetic Field Achieved At Los Alamos
New submitter schrodingersGato writes "Researchers at the Los Alamos campus of the National High Magnetic Field Laboratory achieved a record-setting 100.75 Tesla magnetic field. To do this, scientists placed a resistive magnet (a sophisticated electromagnet) coupled to massive bank of capacitors within another magnet fixed at a 'lower' magnetic field. A short-lived pulse two million times stronger than the Earth's magnetic field was generated. The magnet itself made an eerie sound as it was energized (video). Prepare for the birth of Magneto!"
How much stronger would a field have to be to protect a hypothetical ship the size of the space shuttle from solar winds and other non-EM ionizing radiation in interplanetary space?
If 100 tesla is achievable now, then I can imagine it wouldn't take long before a field can be generated which would be powerful enough to provide a buffer against most ionizing radiation a la Earth's own magnetic field, but I could be way in the realm of science fiction with this thought.
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>> A short-lived pulse two million times stronger than the Earth's magnetic field was generated.
In unrelated news, government researchers have issued an RFP for 100 new disk drives and data recovery services.
There ain't no SI unit named after Edison. beeeotch!
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
Actually, for all you physicists out there and just for goggles, what kind of power and size of device would you need to give a spacecraft a magnetic field strong to protect that craft from radiation in the same manner the earth's magnetic field protects us?
When Fascism comes to America, it will call itself Anti-Fascism, and tell you to give up your guns.
What insights will we gain from this breakthrough? As it stands it sounds as impressive as the Burj Khalifa in Dubai. Cool, but sort of useless.
Why did they choose 100 Tesla as a target? Why not 117 Tesla? That is even more!
This would make an excellent </Mr. Burns> death-ray if it did rip all the blood from someone else's body.
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
The issue is not the magnetic field strength (which only aligns the nuclear spins). Instead, the major hurdle would be that microwave frequency radiation would be needed to image a person at that field strength (rather than radio-frequency) at typical MRI field strengths, thus cooking the person by dielectric heating. Also, the iron in hemoglobin is paramagnetic, not ferromagnetic. It is aligned by the magnetic field, but is not at risk of being torn out of the body. Though if you like iron shavings with your breakfast cereal...
That wasn't change.
How much stronger would a field have to be to protect a hypothetical ship the size of the space shuttle from solar winds
The deflection of charged particles in a magnetic field is roughly proportional to the strength of the field and the "thickness" of the field i.e. the distance that the charged particle travels through it. So (ignoring important complexities like varying field strength, ship geomtery etc.) a 100T field 1 m around the craft would be roughly as effective as a 1T field extending 100m around the craft.
The strongest MRI currently used on humans is 9.1T and a 13T MRI scanner is being built - might already be finished. Given that the 9.1T is good enough to see individual neurons, the 13T scanner might be good enough to start seeing the fine structure of the synapses. I look forward to seeing the photos that will hopefully be published once the scanner gets going.
It would be interesting to see how far you could go before the damage becomes excessive. Would it be possible to build an MRI capable of directly observing the proteins that control and form memories? Could you observe the tau protein unpeeling as Alzheimer's begins? (Long before structural changes occur, which in turn is long before symptoms appear.)
How about archaeological uses? Could a high-power MRI reveal something of the mental state of the various bog bodies that have been found? What about Otzi? If we can directly observe memory structure, could we interrogate his brain to find out what happened to him?
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
MRi is technically just a euphemism for Nuclear Magnetic Resonance (NMR) imaging. The N was dropped because it of the obvious stigma that word possesses outside of scientific circles. We already have structures of these proteins solved by NMR. The next challenge is indeed to view these molecular systems in-vivo. I doubt that these techniques will actually make it out of the research setting. MRi's with fields higher than 3T are having trouble being approved by the FDA for clinical use. This is complicated by the fact that high field instruments are really expensive to begin with. Other scientists are working hard to advance the image quality in other ways.
Agilent (Varian) has a system that is up to 16T and Bruker has systems up to almost 12T. Technically, the highest field MRI is at the NHMFL (21T at 900MHz), but it cannot accept live samples so it doesn't count...
My bad, it's 11T. See links below for info.
This is the existing 9T MRI with 80cm bore.
http://medgadget.com/2007/12/94_tesla_monster_mri.html
This is the whole-body 11T MRI being built
http://irfu.cea.fr/en/Phocea/Vie_des_labos/Ast/ast_visu.php?id_ast=3058
Some of the underlying technology:
http://www.microwavejournal.com/articles/print/2551
http://www.microwavejournal.com/articles/10402-software-platform-for-mri-phased-array-system-design-optimization
http://www.hfmmagazine.com/hfmmagazine_app/jsp/articledisplay.jsp?dcrpath=AHA/PubsNewsArticleGen/data/0403HFM_NEWS_Construction
http://www.aapm.org/meetings/05am/pdf/18-2826-94182-387.pdf
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
The issue is not the magnetic field, its the dielectric heating from the microwave-frequency radiation needed to detect nuclear spins at the higher magnetic fields. Yes, the cell-phone radiation issue has raised the question of whether other (yet undetected) phenomena can occur in cells (like changes in gene regulation/expression) in response to microwave radiation. The issue of cooking a patient is by far a bigger challenge. Patients can get waivers for high field MRIs, but the spectrometers are still not very common (mostly due to their price). Image quality can be improved by other, cheaper methods such as DNP. Most hospitals still use 2-D, black and white (X-ray style) renderings of MRi data due to their policy, level of comfortability, and in some cases law. Also, a limited number of MRi experiments are even approved for diagnostics (even the hyped fMRi/lie detector is not technically FDA approved to treat or diagnose anything). Other than an elite group of specialist physicians and medical research scientists, most clinicians probably would not be able to take advantage of the improved resolution of high field instruments unfortunately.
Molecules absorb at very specific frequencies, so provided you don't emit microwave radiation at the hydroxide bond frequency or any other frequencies "reserved" by biochemistry, you should be safe enough. That means that you need to be very selective about microwave frequency components, which in turn means specific sized magnets won't be usable at all. Those not in the automatically excluded list will depend on how good you are at ensuring genuinely harmful frequencies either don't occur or don't reach the person.
Of course, it's very easy to talk about absorption bands. It's much, much harder to build very high-power devices that stay out of said bands.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)