A team of scientists from Russia and China has developed a model explaining the nature of high-energy cosmic rays (CRs) in our galaxy. These CRs have energies exceeding those produced by supernova explosions by one or two orders of magnitude. The model focuses mainly on the recent discovery of giant structures called Fermi bubbles.
One of the key problems in the theory of the origin of cosmic rays, which consist of high-energy protons and atomic nuclei, is their acceleration mechanism. The issue was addressed by Vitaly Ginzburg and Sergei Syrovatsky in the 1960s when they suggested that CRs are generated during supernova (SN) explosions in the galaxy. A specific mechanism of charged particle acceleration by SN shock waves was proposed by Germogen Krymsky and others in 1977. Due to the limited lifetime of the shocks, it is estimated that the maximum energy of the accelerated particles cannot exceed 1014-1015 eV.
Explaining the nature of particles with energies above 1015 eV is key. A major breakthrough in researching the acceleration processes of such particles came when the Fermi Gamma Ray Space Telescope detected two gigantic structures emitting radiation in the gamma-ray band in the central area of the galaxy in November 2010. The structures are elongated and symmetrically located in the galactic plane perpendicular to its center, extending 50,000 light-years, or roughly half of the diameter of the Milky Way disk. These structures became known as Fermi bubbles. Later, the Planck telescope team discovered their emission in the microwave band.
The nature of Fermi bubbles is still unclear, but the location of these objects indicates their connection to past or present activity in the center of the galaxy, where a central black hole of 106 solar masses is believed to be located. Modern models relate the bubbles to star formation and/or an energy release in the galactic center as a result of tidal disruption of stars during their accretion onto a central black hole. Similar structures can be detected in other galactic systems with active nuclei.
Dmitry Chernyshov (MIPT graduate), Vladimir Dogiel (MIPT staff member) and their colleagues from Hong Kong and Taiwan have published a series of papers on the nature of Fermi bubbles. They have shown that X-ray and gamma-ray emission in these areas is due to processes involving relativistic electrons accelerated by shock waves resulting from stellar matter falling into a black hole. In this case, the shock waves should accelerate both protons and nuclei. However, in contrast to electrons, relativistic protons with bigger masses lose hardly any energy in the galactic halo and can fill the entire volume of the galaxy. The authors of the paper suggest that giant Fermi bubble shock fronts can re-accelerate protons emitted by SN to energies greatly exceeding 1015 eV.
Analysis of cosmic ray re-acceleration showed that Fermi bubbles may be responsible for the formation of the CR spectrum above the "knee" of the observed spectrum, i.e., at energies greater than 3×1015 eV (energy range "B" in Fig. 2). To put this into perspective, the energy of accelerated particles in the Large Hadron Collider is also ~1015 eV.
"The proposed model explains the spectral distribution of the observed CR flux. It can be said that the processes we described are capable of re-accelerating galactic cosmic rays generated in supernova explosions. Unlike electrons, protons have a significantly greater lifetime, so when accelerated in Fermi bubbles, they can fill up the volume of the galaxy and be observed near the Earth. Our model suggests that the cosmic rays containing high-energy protons and nuclei with energy lower than 1015 eV (below the energy range of the observed spectrum's "knee"), were generated in supernova explosions in the galactic disk. Such CRs are re-accelerated in Fermi bubbles to energies over 1015 eV (above the "knee"). The final cosmic ray distribution is shown on the spectral diagram," says Vladimir Dogiel.
The researchers have proposed an explanation for the peculiarities in the CR spectrum in the energy range from 3×1015 to 1018 eV (energy range "B" in Fig. 2). The scientists proved that particles produced during the SN explosions and which have energies lower than 3×1015 eV experience re-acceleration in Fermi bubbles when they move from the galactic disk to the halo. Reasonable parameters of the model describing the particles' acceleration in Fermi bubbles can explain the nature of the spectrum of cosmic rays above 3×1015 eV. The spectrum below this range remains undisturbed. Thus, the model is able to produce spectral distribution of cosmic rays that is identical to the one observed.
Explore further:
Gamma-ray telescopes reveal a high-energy trap in our galaxy's center
More information:
Dmitry Chernyshov et al, Fermi bubbles as sources of cosmic rays above 1 PeV, EPJ Web of Conferences (2017). DOI: 10.1051/epjconf/201614504004
richk
why
Benni
It's just the reverse, electrons have a greater lifetime because the electron is an elementary particle and therefore there is nothing it can decay to. It's lifetime is infinity.
A proton is believed to be composed of three quarks & therefore has something to decay to meaning that a proton is not an elementary particle.
Da Schneib
Da Schneib
You don't have any problem capturing a baseball; you'd never be able to capture an asteroid.
Mimath224
Benni
You're trying to psycho-babble nuclear physics.
Da Schneib
For pedants, a proton is about 1836 times as massive as an electron. "Psycho babble" that, @Lenni. Now go away before I post the simultaneous differential and algebraic relativistic equations you can't solve again and prove again what a fool you are for posting here.
Da Schneib
This is why people who talk about science need to understand mathematics. Those who don't and won't learn are idiots.
jonesdave
Nope. Just you misunderstanding the term 'lifetime' in this context. It means its lifetime as a free electron, as explained by DS. Not how long before it decays to nothingness!
Kron
Chris_Reeve
Aug 19, 2017Benni
Hey Schneibo.........you were answering questions that weren't being asked by richk, but good Copy & Paste from WikiPedia anyway, but that's all it was, just a Copy & Paste.
Benni
Nope, that wasn't what rihk's question was about, go back & reread his question & you'll better understand why schneibo was answering a question that wasn't being asked. Maybe schneibo could better spend his time learning about what a Differential Equation looks like, much less being able to solve one.
cantdrive85
Whydening Gyre
gravitationally derived "concentric" layers...
Captain Stumpy
the study mentions as it's evidence:
-31 different references
-observed CR spectrum
-plus a model that "provides a natural explanation of the observed CR flux, spectral indices, and matching of spectra at the knee"
so it's historical data that is based upon experimentation that builds a picture that can be modeled, then explains the observations
so now lets look at the idiot eu evidence from cantdrive which is:
https://www.youtu...2di5phM0
so, the idiot eu can't provide a working model
they make claims based upon their belief
then they state it must be [insert pseudoscience jargon claim] because modern physicists ignore them
and they wonder why they're laughed at?
Whydening Gyre
Symmetry/balance is EXACTLY what it does.
But hardly inappropriate. Mass interaction produces force reactions.
Okay, ya got me... what is an FB?
Whydening Gyre
Wrong Photonic interaction is the decay methodology for electrons.
HUNH?!?!? A Nuclear Tech says this?!?!?
Captain Stumpy
he is probably referring to Fermi Bubbles
from the abstract and title https://www.epj-c...4004.pdf
Mimath224
@ Whydening Gyre The Standard Model does not list the Proton as an Elementary particle. I understand that although Proton decay has not been observed some GUT's suggest that it would decay into a Π + e where Π further decays into γ
Da Schneib
Proton decay has long been searched for and never detected. It is currently known to be greater than a bit more than 1 x 10³⁴ years. Hyperkamiokande will look for evidence beyond this value, provided it is built; it's currently projected to begin construction in 2018, but has already been delayed once.
Electrons are believed to be stable. I am not aware that anyone has seriously proposed electron decay even theoretically.
Whydening Gyre
As I smack my forehead and say "doh!'...
Thanks, Cap'n and MiMath -
I guess I'll blame the Tequila...:-)
J Doug
Dmitry Chernyshov et al, & the rest of the Russinas need to get up to speed on this topic that has been more fully researched long before they wrote this.
Jasper Kirkby photographed inside the CLOUD chamber.
http://cds.cern.c...77?ln=de
Henrik Svensmark, being a scientist, devised experiments of his own to test his theory and that demonstrates how science works. It is not about a group of self-serving charlatans proclaiming that "the debate is over" when they have no experiment that shows that CO₂ drives the earth's climate or even provide the mathematical derivation of CO₂ forcing.
"Svensmark: Evidence continues to build that the Sun drives climate, not CO2″.
https://www.youtu...embedded
J Doug
"One Year of Clouds Covering the Earth
At any moment, about 60 percent of the earth is covered by clouds,(Acording to a NASA web page 70% of the earth is covered by clouds) which have a huge influence on the climate. An animated map showing a year of cloud cover suggests the outlines of continents because land and ocean features influence cloud patterns."
http://www.nytime...uds.html
J Doug
J Doug
Chris_Reeve
Aug 20, 2017Captain Stumpy
2- i see you're still avoiding the studies that prove you wrong: still not providing a single study to refute the posted evidence that says you're an idiot
thanks for proving you're a lair too
.
.
@hannes/reeve the idiot eu multi-sock pseudoscience TROLL 1- i've already posted the evidence showing Astro's know about double layers - quit proving you're stupid
2- in no way, shape or form has cd, the eu cult or you ever provided any evidence whatsoever to prove any of the miraculous unobserved evidence you claim causes [insert observation here]
just saying "it's lab observation" means absolutely dick
provide the lab evidence that shows [x] proves yoru eu cult theory or STFU already
it's not like plasma physics aint scalable
idiot troll
Captain Stumpy
in point of fact, i linked evidence, you idiot
my campaign is against your claims that double layers create every f*cking known plasma astrophysics phenomenon observed in about every astrophysics article that cd and you post in
especially since you have never once provided a link to a reputable peer reviewed journal study that provides any evidence showing that [x] observation is linked to [y] claim
no one gives a sh*t about your beliefs - they care about the evidence
stop posting pseudoscience cult dogma and start linking evidence and people will take you more seriously
until then - you're posting religion, not science
RealityCheck
What you point out re Water Vapor is correct, mate; I have long pointed overnight clear-sky cold and freezing-desert examples.
HOWEVER, whatever effect from water vapor, an INCREASED CO2 effect makes it worse!
That is why the RUNAWAY GREENHOUSE 'tipping point' is so dangerous!
The FEEDBACK which will ensue between more-CO2 warming AND more-water-vapor in atmosphere due to warming....and so on....will AMPLIFY the effects of BOTH additional CO2 AND additional Water Vapor in the atmosphere!
So, J Doug, isn't it obvious that in order to prevent more water vapor 'load' in atmosphere we should reduce 'additional' CO2 related warming effect? :)
RealityCheck
@Da Schneib. It's heartening to see that you/others now agree that the galaxy does have an overall magnetic-field pattern which accelerates/confines AND SORTS charged particles into various streaming features/flows in various directions without necessarily re-combining until they are well into deep space away from such 'sorting' and 'separation/acceleration' mag-fields. This is only relatively recently 'discovered' by astrophysicists, as previous discussions have highlighted in the past. :)
@jonesdave. Beware simplistic views/conclusions. For every 'free' electron there is a 'free' proton, yes? So claims of 'free lifetime' are AVERAGE, NOT SPECIFIC. :)
RealityCheck
The fuller passage should have read: "For every 'free' electron there is a 'free' proton OR 'ionized' nucleus of an atom heavier than hydrogen."
Cheers. :)
Chris_Reeve
Aug 20, 2017J Doug
RealityCheck; Please note the following current info from Summit Camp, Greenland.
Summit Camp, Greenland
7:15 PM -02 on August 20, 2017 (GMT -0200)
Temperature= 3 °F Feels Like 3 °F
Pressure 29.98 in
Visibility 5 miles
Clouds
Dew Point 2 °F
Humidity 95%
Rainfall 0.00 in
Snow Depth Not available.
Elev ft 72.58 °N, 38.45 °W | Updated 3 hr ago
https://www.wunde...45000076
This report is somewhat amazing because I know from having spent many years in the arctic that the humidity is generally very low.
J Doug
In 1942, eight U.S. WWII aircraft (2 bombers, 6 fighter planes) emergency-landed on the Southwestern coast of Greenland after encountering severe weather. The crews were rescued and the planes ultimately had to be abandoned at the landing site. So there the planes sat on the Greenland ice sheet, undetected, for more than 4 decades. When the planes were finally found in 1988, 46 years after crash-landing on the Greenland ice sheet, they were buried under 260 feet (79 meters) of ice. In other words, between 1942 and 1988, the Greenland ice sheet gained mass at a rate of 57 feet (17 meters) per decade at that location.
cantdrive85
WG, take a look at CR's link. There is an image of a charge-loaded iron sphere shown through an "evolution" of the sphere developing a series of layers. Gravity has little to no effect on the process, it is electrodynamic. Those electromagnetic forces at work are nearly 40 orders of magnitude stronger than gravitational effects.
J Doug
J Doug
Greenland ice sheet mass balance reconstruction. Part I: net snow accumulation (1600-2009)
Journal of Climate 2012 ''We find a 12% or 86 Gt y-1 increase in ice sheet accumulation rate from the end of the Little Ice Age in ~1840 to the last decade of the reconstruction. This 1840-1996 trend is 30% higher than that of 1600-2009, suggesting an accelerating accumulation rate. The correlation of Ât(G) with the average surface air temperature in the Northern.''
http://journals.a...-00373.1
''Increased ice loading in the Antarctic Peninsula since the 1850s and its effect on Glacial Isostatic Adjustment Accumulation increase results in up to 45 m extra ice thickness over 155 years
http://onlinelibr...2559/pdf
J Doug
Snow flurries. Passing clouds.
Feels Like: -110 °F
Forecast: -66 / -60 °F
Wind: 13 mph ↑ from Southeast
Location: Amundsen-Scott South Pole Station
Current Time: Aug 21, 2017 at 10:14:20 am
Latest Report: Aug 21, 2017 at 6:00 am
Visibility: 6 mi
Pressure: N/A
Humidity: 55%
Dew Point:-69 °F
https://www.timea...uth-pole
Remember in 2013 when the Chopper rescue for Russian ship MV Akademik Shokalskiy as Aurora Australis is forced to abandon rescue bid.
A Chinese helicopter flew over a Russian ship, trapped in Antarctic sea-ice since Christmas Day, as icebreakers make their way to help the stranded vessel.
http://www.news.c...91671102
Caliban
If my understanding is correct to this point, then do I also understand correctly that they are saying that ANY SN can re-accelerate any of these protons/nuclei that encounter the SN's shockwave?
And, if that is the case, it would seem then, that as far as experiment goes, we only need look for a stream of these hyper-accelerated protons coming from a confirmed SN
yep
https://physics.a...cs.6.131
Caliban
Your study only suggests the possibility for double layers to cause such re-acceleration outside of the solar system.
While it doesn't seem like too much of a stretch, it also isn't confirmed, especially as the energy levels confirmed in the study are much lower than those discussed in this PO article, and entirely fail to consider heavier particles than electrons.
It's important not to assume what hasn't been proven, and also, not to compare apples to oranges when promoting a pet theory, especially one as controversial as the EU people support.
Chris_Reeve
Aug 20, 2017cantdrive85
Whydening Gyre
Ummm.. It's winter down there...?
And.... Aren't you a little off topic for this article?
cantdrive85
Yet, we "know" the Sun is powered from within. And we "know" we can treat astrophysical plasma as an ideal gas with MHD with the fields frozen-in contrary to all empirical evidence. And we compare galactic and extra-galactic gravitational dynamics (apples) to solar system dynamics (oranges). And we "know" dark matter exists. But to suggest that the astrophysical plasma should behave similarly to laboratory plasmas is "controversial". The logic evades me.
Whydening Gyre
Errr.... it's summer in the North Hemisphere...?
Whydening Gyre
Controversial - may be a little over the top.
Plain "silly" works.
let me try and explain simply -
Completely different gravitational dynamic.
Whydening Gyre
They HAVE to be in order to counter the STRONG local gravitational (as well as her magnetic) field of Earth.
Chris_Reeve
Aug 21, 2017Kron
No, you misunderstand. From paper:
" Thus our model can be described in the following way: SNRs in the disk accelerate particles with power-law distribution up to energies of 3×10^15 eV and Fermi bubbles further reaccelerate these particles up to 10^18 eV"