Could dark baryons explain dark matter?

(PhysOrg.com) -- "The prevailing belief about dark matter particles is that they should be about 100 or more times heavier than protons," Subir Sarkar tells PhysOrg.com. "However, we were thinking about the possibility of lighter particles that can constitute dark matter, which may be more easily detectable with current experiments."

Sarkar is a Professor at the University of Oxford in England. Along with Mads Frandsen, he has been working to show that asymmetric "dark baryons" can be a candidate for cold . This is a different approach, since dark matter is assumed to be heavy 'supersymmetric' particles that are very weakly interacting. Sarkar and Frandsen suggest though that dark matter could be much lighter, asymmetric (i.e. just particles and no antiparticles) and interact more strongly. Their work is published in : "Asymmetric Dark Matter and the sun."

“We have known for some time that most of the matter in the universe is not the (baryonic) matter that we are are made of. However, we know, from various measurements that dark matter is what holds different structures together through gravity,” Sarkar says. “We don’t know what it is, but we know it is out there.”

For years, it has been thought that must be relatively heavy, and that they do not interact at all with other dark matter particles and only very weakly with ordinary matter. Thus the origin of dark matter is totally unrelated to that of baryons, which is in itself a mystery. If there had been equal amounts of (baryonic) matter and antimatter in the , everything should have annihilated. “Clearly the universe is not empty so there must have been some matter-antimatter destruction, but there is an excess of matter that has survived,” Sarkar points out.

“So there must have been an initial excess of matter over antimatter”. If baryon makes it possible for matter to exist in the universe, could it be the same for dark matter? “If there is a new “dark baryon” which is five times as heavy as a baryon and has the same relic asymmetry, then dark matter would contribute five times as much as ordinary matter in the universe, as is indeed observed,” Sarkar explains. He adds that this was first proposed by the physicist David B Kaplan.

Modeling this idea isn’t too hard, Sarkar says. “Various physicists have constructed models for a new particle that would acquire the same excess of particles over anti-particles as baryons have.”

Sarkar and Frandsen point out that gravity would affect these dark baryons, and that they would even interact with each other, although not very strongly, thus influencing the formation of galaxies. In order to test the idea of dark baryons, Sarkar and Frandsen suggest an experiment using the sun.

“There is a simple point made 15 years ago, that dark matter will be captured when it comes close to the sun, just like ordinary matter. If these particles exist, then they will inevitably fall into the sun, and begin orbiting inside it, thus transporting heat outward, through their occasional collisions,” Sarkar says.

He goes on to explain that, because we know a great deal about the sun, it is possible to work out how much heat should be transferred out, and calculate the change in the flux of solar neutrinos, particles that are very sensitive to the core temperature. “If dark matter particles are asymmetric, they can build up in the sun to higher levels since they aren’t annihilating, and we could see a measurable reduction in the flux of solar neutrinos.”

Sarkar says that it should be possible to test this relatively soon. “There are already experiments looking for dark matter - however, they are looking for much higher masses. If detectors could be redesigned to be sensitive to lower masses, then they will find it soon. Another way is to measure solar neutrino fluxes with high accuracy to determine if dark matter has slightly cooled the solar core.”

Sarkar admits that so far, this is just a theory. “We don’t know what dark matter is, but scientists would very much like to find out, since it has profound implications for the nature and origin of the universe.”

“This is an idea we’re putting out there, to say it is a possibility. It predicts signals to look for, and provides an explanation for some puzzling features of the sun. We hope that experimenters will check this out, even if only to prove us wrong.”


Explore further

Sun's dark matter trap

More information: Mads T. Frandsen and Subir Sarkar, “Asymmetric Dark Matter and the Sun,” Physical Review Letters (2010). Available online: link.aps.org/doi/10.1103/PhysRevLett.105.011301

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Jul 20, 2010
I highly doubt that an experiment to detect dark matter on a microscopic scale would yield results that dark matter detection on a macroscopic scale could not, at least as far as existence is concerned.

Rather than creating a new dark baryonic particle to satisfy our whim, isn't it also possible that dark matter is excessively heavier than "light" matter due to the Higgs or top quarks?

Jul 20, 2010
Quote:
“We have known for some time that most of the matter in the universe is not the (baryonic) matter that we are are made of. However, we know, from various measurements that dark matter is what holds different structures together through gravity,” Sarkar says. “We don’t know what it is, but we know it is out there.”

No, we don't *know* there is any dark matter! It is just inferred from the current paradigm in physics, which of course could be wrong...

Jul 20, 2010
Quote:
"We have known for some time that most of the matter in the universe is not the (baryonic) matter that we are are made of. However, we know, from various measurements that dark matter is what holds different structures together through gravity,"
Sarkar says. "We don’t know what it is, but we know it is out there."

No, we don't *know* there is any dark matter! It is just inferred from the current paradigm in physics, which of course could be wrong...

Jul 20, 2010
Quote: "We have known for some time that most of the matter in the universe is not the (baryonic) matter that we are are made of. However, we know, from various measurements that dark matter is what holds different structures together through gravity," Sarkar says. "We don’t know what it is, but we know it is out there."

No, we don't *know* there is any dark matter! It is just inferred from the current paradigm in physics, which of course could be wrong...

Jul 20, 2010
Quote:
["We have known for some time that most of the matter in the universe is not the (baryonic) matter that we are are made of. However, we know, from various measurements that dark matter is what holds different structures together through gravity,"
Sarkar says. "We don't know what it is, but we know it is out there."]

No, we don't *know* there is any dark matter! It is just inferred from the current paradigm in physics, which of course could be wrong...

Jul 20, 2010
I am terribly sorry for the multiple comments! Hopefully the mods can delete 3 of them!

(I got an error message when clicking "submit", and discovered the mistake too late...)

yyz
Jul 20, 2010
No mention at all of axions, a light, non-annihilating DM candidate? Several searches for axions are already underway.

CAST: CERN Axion Solar Telescope http://en.wikiped...elescope

ADMX: Axion Dark Matter Experiment http://en.wikiped...periment

The Wiki axion page ( http://en.wikiped...i/Axions ) has descriptions of these and other axion searches - past and present.


Jul 20, 2010
3 comments from the truest of crackpots....get a clue, read. do something besides let your thought be heard

Jul 20, 2010
Probable composition of dark matter by mainstream peer-reviewed theories ordered by their average rest mass: quintessence, mirror matter, axions, inflatons, photons, neutrinos and sterile neutrinos, chameleon particles, dark baryons, antiparticles, fotinos, gravitinos and WIMPs, SIMPs, MACHOs, RAMBOs, DAEMON and micro-black holes.

Isn't it nice to be payed as a physicist?

Jul 21, 2010
@zslewis: crackpot is dead-on. You aren't thinking. Science *knows* nothing. It only assumes what hasn't been disproven.

Jul 21, 2010
^
|

So mental health facilities have been plugged on-line finally? Makes me wonder whether it is part of the therapy, or just a result of revenue maximalization efforts by the involved providers(?) :-)

I believe you could put good use to one of these:
http://www.realst...ets.com/

Best regards ;o)

On a side note: "Dark" seems to be the new pink ^^

Jul 24, 2010
Dark matter will just be neutrinos of 1.5 eV mass. Searching your shoes so long, they are just on your feet. But this is not sexy, so our hype-based science will neglect the evidence till that is really impossible. 2015, measurement of the neutrino mass. Till then, more hypes.

Jul 24, 2010
Dark matter will just be neutrinos of 1.5 eV mass.
And... what is it by now? How did you deduced it? I've problem with explanation of DM by neutrinos in connection to Pioneer anomaly, for example. Why these neutrinos didn't escape from solar system already like protons of solar wind? How is it possible, their concentration correspond the product of Hubble constant and speed of light so well? And how omnidirectional expansion of space would manifest, after then?

Jul 27, 2010
Dark matter will just be neutrinos of 1.5 eV mass.
And... what is it by now? How did you deduced it?


The result follows from fitting lensing date of galaxy cluster Abell 1689 by isothermal fermions. The best case is neutrinos, their mass is then 1.5 eV.
They offer no help for the Pioneer anomaly, not even for galactic DM. The latter consists of baryons locked up in MACHOs of earth mass.
The global neutrino concentration is 56 per cubic cm, per degree of freedom, comparable to the 205 per cc of photons. The neutrinos are now condensed on galaxy clusters, making these act as a strong lens. This condensation is expected to have reionized the intercluster gas, making it X-ray gas, without help of heavy stars. On bigger scales, matter is isotropic.

Aug 02, 2010
When articles here measure velocity of Neutrinos as less than c and expressions of +ve mass for neutrinos then it follows that neutrinos will orbit galaxies. Such concentration of neutrinos may have significant effect on galaxy mass but I need more info on sheer number of neutrinos and because of small size they are hard to count.

Aug 03, 2010
"Could dark baryons explain dark matter?"

Fer sure! Just like Tooth Fairy baryons explain tooth fairy matter, once a day and twice on Sundays!

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