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Decades-old Scientific Paper May Hold Clues To Dark Matter
sciencehabit writes: Here's one reason libraries hang on to old science journals: A paper from an experiment conducted 32 years ago may shed light on the nature of dark matter, the mysterious stuff whose gravity appears to keep the galaxies from flying apart. The old data put a crimp in the newfangled concept of a 'dark photon' and suggest that a simple bargain-basement experiment could put the idea to the test. The data come from E137, a "beam dump" experiment that ran from 1980 to 1982 at SLAC National Accelerator Laboratory in Menlo Park, California. In the experiment, physicists slammed a beam of high-energy electrons, left over from other experiments, into an aluminum target to see what would come out. Researchers placed a detector 383 meters behind the target, on the other side of a sandstone hill 179 meters thick that blocked any ordinary particles.
... but does it shed light on how to transform luminiferous aether into phlogiston? Personally, I suspect it has something to do with walking under a ladder while saying "bloody Mary" into a mirror three times, but I can't fit the proof in the margin.
TFA says the experiment saw nothing, and that this somehow rules out certain masses of dark photons.
I suppose that I've been around here long enough to not expect any better.
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I run a similar beam dump experiment each morning wherein I slam a beam of high energy urine into a ceramic containment vessel full of dark matter and use the resulting patterns as an augury to reveal the auspices of the coming day.
Available for free: 2.5E36 high-energy electrons (~ 10GeV - 100 GeV). Last used in 1982, kept in a pet-free, smoke-free particle accelerator.
Local pick-up only; bring your own magnetic container.
* do NOT contact me with unsolicited services or offers
Thirty- two years ago? Wow! Imagine what life was like in that primitive era.
And it started out like this.
Life is not for the lazy.
Dark photons, or darkons , emitted by the boundary layer could simultaneously explain the missing mass and energy of the universe. Do I smell a Nobel prize?
How can I believe you when you tell me what I don't want to hear?
This story seems like click bait the way it just leaves it as a cliffhanger. so you bombarded an aluminum plate and .... a superhero aluminum man emerged? what what?.... how did this submission get promoted to a front page story? I'm surprised it did not end with "your jaw will drop when you see what happened next".
Some drink at the fountain of knowledge. Others just gargle.
My crystal ball suggests that the phrase "dark matter" is wildly misleading, and when we figure out the root cause of the disparities between our models and our observations, the end-result won't be very similar to anything suggested by this phrase.
It should produce plenty of B-quality science fiction, though.
How do you have "leftover" high energy electrons? Sounds like something you use to send interns on a wild goose chase.
"Get me that jar of high energy electrons from the storeroom in the sub-basement. They were leftovers from another experiment."
The general quality of scientific publications has dropped greatly since the 1940s. Anyone with access should go check out some old papers on their topic. These days the articles in medicine/bio consist of mostly "p0.05 means my theory is true" and no attempt to rule out alternative explanations.
In the experiment, physicists slammed a beam of high-energy electrons, left over from other experiments, into an aluminum target to see what would come out.
Let's all share! What do _you_ do with all those left over high-energy electrons you've always got lying around?
This Space Intentionally Left Blank
Dark matter is primed for a whole new set of discovery, now that Dr. Sheldon Cooper has begun his research in the field.
Dark photons come from dark suckers.
Now get offa my lawn!
>> physicists slammed a beam of high-energy electrons, left over from other experiments ...I was wondering what was inside all those carboard boxes under the stairs.
I got about 1 paragraph into the article before it became obvious that the author had no clue what the hell he was talking about. Maybe the old paper was better, but I don't have the patience to try to find out. From TFA:
They would interact only through the feeble weak nuclear force—one of two forces of nature that ordinarily flex their muscle only within the atomic nucleus—and could disappear only by colliding and annihilating one another
So many things wrong just in that sentence
1) Weakly Interacting Massive Particles (WIMPs) do have very low interaction cross sections (read: rates). There's sometimes an unfortunate ambiguity in the fact that phycisists have no imagination and gave two of the fundamental forces the names Strong and Weak. To say something interacts Weakly means that it interacts by exchange of W or Z bosons, not just that it has a low rate. However the WIMP interaction cross section has been known to be sub-Weak by several orders of magnitude for decades.
2) The Weak force's most obvious manifestation is in the production or absorption of neutrinos (beta decay or inverse beta decay) in a nucleus, but that's certainly not the only place it shows up; it's the mechanism for neutrino-electron scattering, muon decay, and a whole bunch of other stuff up to driving supernova explosions
3) Self-annihilation is the vanilla model for WIMP transformation, but there are plenty of sundaes-with-cherries-on-top models like self-interacting dark matter, which is discussed about 2 sentences later. Also, the chi is the symbol for the supersymmetric neutralino, often equated to a vanilla WIMP, and is not at all specific to the self-interacting dark matter model.
In short, cbtfaij;dr (can't bother to find an intelligent journalist; don't read)
This article looks like an attempt to reopen the discussion about libraries in Canada discarding some old manuscripts. Nice try, but submitter picked a poor example.
"All of this has to be done in a very tight straitjacket."
Pretty much sums up the whole subject.
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Duh inglish langwage evolvz. Get over it.
I wish someone would locate the Feynman quote about effects that lie just beyond current measurements. I recall the comment was one should be especially skeptical of a theory that predicts effects just below the detection threshold. When an experiment with greater sensitivity also has a null result, the theory gets modified to explain an even tinier effect. Such a theory can never be disproved. I also remember when the instability of the proton was a hot idea. I think the theorists kept increasing the proton's lifetime until they finally gave up.
There are so many really smart people competing for physics jobs that the pressure to create a new theory is enormous and it is safer to concoct a theory that explains unmeasurable effects
If you look at the history of the article, it was pretty much written as a whole several years ago. Not even many remarkable people have that long biography pages, which almost makes me think if he actually wrote the whole page himself.
Scientists have come with that unifying theory - is it because they don't really believe in an empty universe? Yes one that is not empty! In other words, space is not space, it's actually something that they don't understand and are trying to put it in terms of a particle. The term that I have heard used is the 'fabric of space' or spacetime. Einstein said that space is curved, so that when you approach a large bodies of matter while you are actually going straight, it's space that is curved. So, that one goes straight around the object. But they are saying now that space must be something so it's called dark matter?