Astrophysicists suggest behavior of Fermi bubbles may be explained by dark matter

Mar 07, 2013 by Bob Yirka weblog
The regions of the sky considered in our analysis. Credit: arxiv.org/abs/1302.6589

(Phys.org) —Astrophysicists Dan Hooper and Tracy Slatyer of Fermi National Accelerator Laboratory, and Princeton University respectively, have written a paper—and uploaded it to the preprint server arXiv—in which they suggest that a massive outflow of charged particles from the center of the Milky Way galaxy, may be partly due to collisions between dark matter particles that result in their annihilation. Their research is part of an ongoing effort by various scientists around the world to better explain, or prove the existence of dark matter.

Dark matter, scientists theorize, is matter of a type that cannot be seen, though research suggests it makes up approximately 84 percent of all matter that exists in the universe. No one knows if it really does exist, however, as the term came about to explain on matter that is visible but could not be explained by any other means. Because of that, researchers have dedicated countless hours to its study and to finding real evidence of its existence. In this new effort, the research duo suggest that the massive outflow of charged particles that can be observed stretching above and below the center of the , could be attributed to collisions between dark matter particles, causing their annihilation and the subsequent creation of the building blocks of —and emitting charged particles as part of the process.

Fermi bubbles, as they are known, are gamma ray outflows of charged particles traveling at nearly 106 m/s. They form what look like two lobes above and below the center of the Milky Way Galaxy. Some of these rays are thought to come about due to the black hole that is thought to exist at the galaxy's center. Likewise, some are also thought to come about due to material given off by stars when they explode. Taken together, however, the identified sources don't add up to produce as many of the charged particles as can be observed. This is because, the researchers theorize, some of the gamma rays are due to running into each other, obliterating themselves in the process. As they do so, they give rise to tau leptons and emit . And that, they claim, adds credence to dark matter theory.

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More information: Two Emission Mechanisms in the Fermi Bubbles: A Possible Signal of Annihilating Dark Matter, arXiv:1302.6589 [astro-ph.HE] arxiv.org/abs/1302.6589

Abstract
We study the variation of the spectrum of the Fermi Bubbles with Galactic latitude. Far from the Galactic plane (|b| > 30 degrees), the observed gamma-ray emission is nearly invariant with latitude, and is consistent with arising from inverse Compton scattering of the interstellar radiation field by cosmic-ray electrons with an approximately power-law spectrum. The same electrons in the presence of microgauss-scale magnetic fields can also generate the the observed microwave "haze". At lower latitudes (b < 20 degrees), in contrast, the spectrum of the emission correlated with the Bubbles possesses a pronounced spectral feature peaking at 1-4 GeV (in E^2 dN/dE) which cannot be generated by any realistic spectrum of electrons. Instead, we conclude that a second (non-inverse-Compton) emission mechanism must be responsible for the bulk of the low-energy, low-latitude emission. This second component is spectrally similar to the excess GeV emission previously reported from the Galactic Center (GC), and also appears spatially consistent with a luminosity per volume falling approximately as r^-2.4, where r is the distance from the GC. We argue that the spectral feature visible in the low-latitude Bubbles is the extended counterpart of the GC excess, now detected out to at least 2-3 kpc from the GC. The spectrum and angular distribution of the signal is consistent with that predicted from ~10 GeV dark matter particles annihilating to leptons, or from ~50 GeV dark matter particles annihilating to quarks, following a distribution similar to the canonical Navarro-Frenk-White (NFW) profile. We also consider millisecond pulsars as a possible astrophysical explanation for the signal, as observed millisecond pulsars possess a spectral cutoff at approximately the required energy. Any such scenario would require a large population of unresolved millisecond pulsars extending at least 2-3 kpc from the GC.

via ABC

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User comments : 20

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vacuum-mechanics
1 / 5 (16) Mar 07, 2013
Dark matter, scientists theorize, is matter of a type that cannot be seen, though research suggests it makes up approximately 84 percent of all matter that exists in the universe. No one knows if it really does exist, however, as the term came about to explain gravitational pull on matter that is visible but could not be explained by any other means….

Maybe this simple physical view could help to settle the matter.
http://www.vacuum...14〈=en
Dr_toad
Mar 07, 2013
This comment has been removed by a moderator.
Birger
5 / 5 (8) Mar 07, 2013
"charged particles (gamma rays) traveling at nearly a third the speed of light"
(rolls up newspaper)
"Bad science writer! BAD!"
brt
4.6 / 5 (10) Mar 07, 2013
I was initially going to object to the characterization of charged particles as "gamma rays", but that's a small thing compared to the assertion that 17th century aether is really the answer. Ridiculous.


I agree, guy's an idiot. I would say that when I read comments like those, I automatically imagine the person typing it is mentally disabled; but I don't want to insult mentally disabled persons by making that association.
Maggnus
4.9 / 5 (7) Mar 07, 2013
Lol! And no doubt ol Zephyr will be along shortly to add his nonsense!

@ Birger-- hilarious, I almost snorted my coffee out my nose :)
Q-Star
5 / 5 (10) Mar 07, 2013
Lol! And no doubt ol Zephyr will be along shortly to add his nonsense!


I was thinking that the writer had interviewed Zeph. Because everyone knows that electron ducks moving through the aether at one third c are responsible for Fermi Foam.
ValeriaT
1 / 5 (9) Mar 07, 2013
The model of dark matter particles collision doesn't explain the most prominent feature of Fermi bubbles - why they're oriented perpendicularly to galactic plane. The highest concentration of dark matter is right at the galactic plane, so that the highest intensity of dark matter collisions should appear just there - or not?

But we know about many other examples of such bubbles - like this one. These bubbles are apparently formed with scattering of black hole jets, so they're oriented in axial direction. In dense aether model the black hole can emanate the neutrinos in certain extent and their annihilations with gamma ray photons generates the quarks and gamma radiation. At the case of heavier/younger black holes even heavier particles of antimatter can be emanated from black holes. It's process rather close to nucleogenesis of matter around most of quasars ("Big Bang nucleosynthesis").
j_stroy
not rated yet Mar 07, 2013
If it is supposed to be more dominant than visible matter, what does the Standard Model (and others) describe about dark matter in the universe in the distant past?
ValeriaT
1 / 5 (7) Mar 07, 2013
Standard Model doesn't incorporate the dark matter (if we neglect the neutrinos, which aren't considered the main portion of dark matter by mainstream physicists to their detriment). Some ad-hoced models expect the higher concentration of dark matter in the past, which is at least problematic in steady-state universe model (as no universal "past" was here).
cantdrive85
1.4 / 5 (11) Mar 07, 2013
Fermi bubbles, as they are known, are gamma ray outflows of charged particles traveling at nearly 106 m/s. Some of these rays are thought to come about due to the black hole that is thought to exist at the galaxy's center. Likewise, some are also thought to come about due to material given off by stars when they explode.


Well, if these scientists were a bit more informed about plasma physics maybe their paper would be written in such a manner that this author may have a clue. Gamma rays and other forms of sychrotron radiation are expected in plasma double layers as the particles are accelerated to relativistic speeds. The radiation is just that, radiation from the particles and not the particles themselves.

Taken together, however, the identified sources don't add up to produce as many of the charged particles as can be observed.

Until they learn some plasma physics and include the presence of double layers, the "dark ages" of space science will continue.
Maggnus
4.3 / 5 (11) Mar 07, 2013
Hey Zephyr you fraud, people ask questions on a science site to get SCIENTIFIC answers, not the rambling fraudulent diatribe of a pseudo-scientific witch doctor. Why do you feel the need to pollute every thread with your half-witted rantings?

And look, there's cantthink! Excellent, an article on some truly interesting phenomena ovewhelmed by vacuum salesman, an aether inhaler and a plasmatic pin head.
cantdrive85
1.4 / 5 (11) Mar 07, 2013
Hey Zephyr you fraud, people ask questions on a science site to get SCIENTIFIC answers, not the rambling fraudulent diatribe of a pseudo-scientific witch doctor. Why do you feel the need to pollute every thread with your half-witted rantings?

And look, there's cantthink! Excellent, an article on some truly interesting phenomena ovewhelmed by vacuum salesman, an aether inhaler and a plasmatic pin head.

That's funny, I can't recall any actual "SCIENTIFIC answers" made by you. Just derision, claims of superior knowledge , and ad hominem attacks.
"Progress is made by answering questions. Discoveries are made by questioning answers." Bernard Haisch
Maggnus
4 / 5 (8) Mar 07, 2013
That's funny, I can't recall any actual "SCIENTIFIC answers" made by you. Just derision, claims of superior knowledge , and ad hominem attacks.
"Progress is made by answering questions. Discoveries are made by questioning answers." Bernard Haisch


Yea cantthinkindependantly, I am too busy trying to counter the multiple, flood like posts of pissants such as yourself, who pretend their knowledge of science is something beyond that taught to kindergarden students.

Hows them earthquake caused solar storms working out for you there moron?
JIMBO
5 / 5 (2) Mar 08, 2013
Amidst all this belligerence, I have a question which this article crystallized in my brain. We all know that matter & anti-matter can annihilate if they collide, typically w/2 photons emitted.
Musn't there be such a thing as `dark anti-matter' in order for annihilation to occur in a collision w/dark matter ? Appreciate a clear answer.
jibbles
5 / 5 (4) Mar 08, 2013
Amidst all this belligerence, I have a question which this article crystallized in my brain. We all know that matter & anti-matter can annihilate if they collide, typically w/2 photons emitted.
Musn't there be such a thing as `dark anti-matter' in order for annihilation to occur in a collision w/dark matter ? Appreciate a clear answer.


i think dark matter particles are theorized to be their own antiparticle.
cantdrive85
1.4 / 5 (10) Mar 08, 2013
Hows them earthquake caused solar storms working out for you there moron?
So the Earth has this EM field "ya" know, and sometimes this field is buffeted by charged particles which can impart their energy upon this field. We also know that these fields can store energy, and this stored energy must go somewhere. Sometimes it manifests itself in an extra Van Allen belt (electric currents);
http://phys.org/n...eal.html

sometimes that energy leaks into the atmosphere;
http://phys.org/n...eve.html

I think even you acknowledge that solar activity affects the ionosphere, well it's been shown the ionosphere affects telluric currents;
http://onlinelibr...abstract

and it's been shown that telluric currents are directly linked to earthquakes
http://meetings.c...1730.pdf

If you can't see the connection, I wonder who is the real moron.
rah
1 / 5 (6) Mar 08, 2013
it may be Dark Matter, or it may be VooDoo! It may be Dark Magic! How do you explain one thing that you have no idea about by something that you even have less of an idea about? Unless it helps attract MORE FUNDING!!!
vlaaing peerd
1 / 5 (3) Mar 08, 2013
fermi bubbles resemble the quantum-coagulation-foam of the dense cheese model. Visible normal matter can be represented as the yellow cheese and dark matter the holes in between. Similar to how the holes distorts and shapes the cheese around it, dark matter should therefore be detectable by its cheese-distortion-lensing.

The French and Swiss mainstream science conspiracy call it gravitational lensing, but that is because they're stupid and don't know how to make proper cheese.

And they stink too.
ValeriaT
1 / 5 (4) Mar 09, 2013
technically the neutrinos are sorta vacuum bubbles too, but most of similarity ends right there... This is childish/reddit-type attempt for fun, which is much more entertaining to invent, that to read whole day.
Maggnus
1 / 5 (3) Mar 09, 2013
technically the neutrinos are sorta vacuum bubbles too, but most of similarity ends right there... This is childish/reddit-type attempt for fun, which is much more entertaining to invent, that to read whole day.


BAHAHAHA! Technically the quantum ducks swarming Zephyr's conscious thought are kinda act like vacuum bubbles as well, sucking any sign of intellect from the quasi-field of stupid that envelopes the miniscule smart quanta that existed at the magnetic moment of its lost intellegence.
ValeriaT
1 / 5 (2) Mar 10, 2013
The neutrinos in dense aether model are formed with solitons of scalar/longitudinal waves of vacuum in similar way, like the photons are solitons of transverse waves (the analogy with Falaco and Russel's solitons at the water surface comes into mind in this connection). So that the neutrinos do behave like tiny particles stuffed with higher density of energy, than the neighboring particles, i.e. like the bubbles of vacuum. They tend to concentrate in areas where the space-time gets negative curvature (Lagrange points and the neighborhood of massive bodies). They're forming the lightest antimatter particles in this way and the "missing antimatter" in out Universe. The surface gradient of neutrino bubbles makes them only slightly more dense than the vacuum, i.e. massive particles - but as a whole these particles do contain more energy and inertia, than it would correspond their gravitational lensing.

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