Researchers explain the activity of black holes at the centre of galaxy clusters
September 4, 2009
The galaxy cluster NGC507 as seen in three wavelengths. Blue shows the X-ray emission as observed by the Chandra satellite; red depicts the radio waves, which mark the activity of the supermassive black hole, as received by the Very Large Array in New Mexico; and green shows an optical image from the Digitized Sky Survey. The radio waves, and therefore indirectly the black hole's influence, cover a region that extends about 200,000 light years; i.e., they reach the outskirts of the central galaxy in this cluster. (Credits: R. Mittal, Bonn University, CXO, VLA)
(PhysOrg.com) -- Astronomers at the University of Bonn have clarified the connection between black holes at the centre of galaxy clusters and surrounding gas, which serves them as "food". The scientists have produced a ground-breaking study of what could be called "cosmic feeding". It has now been published in the prestigious scientific journal Astronomy and Astrophysics.
A black hole is the term give by astronomers to a cosmic object whose gravitational force is so strong that it draws in everything in the immediate vicinity. Not even light can escape the pull. Scientists expect to find such phenomena at the centres of all major galaxies. Black holes vary considerably in size. Like boxers, they come in different "weight classes". Supermassive black holes can have a mass that is millions, or even billions, of times greater than our sun's.
"Supermassive black holes are not always 'active'," explains Dr. Thomas H. Reiprich. "In fact most black holes simply 'smoulder' away." Dr. Reiprich works at the Argelander Institute for Astronomy in Bonn, where he heads the Emmy Noether Research Group for "Studying the Nature of Dark Energy with Galaxy Clusters". He is particularly interested in understanding the black holes in the cores of galaxy clusters, which are the largest objects in the universe. By looking at the radiation in the vicinity of a black hole, astronomers are able to draw conclusions about their "food situation". The radiation derives from material that is being slowly absorbed by the black hole. This "food" is mainly ingested by the insatiable cosmic bodies in the form of hydrogen gas.
For black holes, gas is only "edible" if it is cooled down sufficiently - much like in real life! "The particles in hot gas move too quickly for them to come close enough to be pulled into a black hole," says Dr. Reiprich. His colleague Dr. Rupal Mittal, the study's principal author, adds, "For that to happen, the gaseous mixture must cool down. Just how long the cooling process lasts can vary. A billion years is very a short period by cosmic standards." The black hole at the centre of a galaxy cluster in which the gas cools "quickly" enough will receive "edible" gas in abundance and be correspondingly active. The centres of galaxy clusters in which these processes take considerably longer are, in turn, far less lively.
Fast-cooling gas as fuel
The idea that all central black holes in galaxy clusters are active if there is sufficient gas available was already postulated by scientists. But the current work by the Bonn research group furnishes the evidence. "Earlier research had identified a high proportion of such galaxy clusters, but we have now been able to demonstrate that it's not just a 70 per cent incidence but applies to all cases," Reiprich sums up. "All galaxy clusters that cool down rapidly, and thus have an abundance of gas available in their interior, reinvigorate supermassive black holes - like a fresh log on a dying wood-fire. In other words, the black holes will really get going if their wide environment is right."
As part of their study, the researchers in Bonn combined the measurement of radio waves with X-ray images of more than sixty galaxy clusters. Thanks to improved data, they were able to examine these phenomena more closely than previous investigations managed to do. Using the X-ray observations they determined which galaxy clusters contain, in their cores, gas that can serve as food for black holes. And, by means of radio data, the Bonn-based scientists analysed the activity of supermassive black holes.
More information: Astronomy and Astrophysics,Volume 501, Issue 3, 2009, pp. 835-850; DOI: 10.1051/0004-6361/200810836
Provided by University of Bonn (news : web)
Jul 24, 2007 |
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Repulsive interactions between neutrons prevent the formation of Black Holes.
Massive compact objects at the center of galaxies (and stars) are neutron stars.
Repulsive interactions between neutrons cause these objects to "evaporate" by neutron-emission. The neutrons decay in a few minutes to Hydrogen (H).
Some of the H waste product may fuse into heavier elements, as does H moving up from the solar core, but some H escapes to interstellar space.
Just like the 50,000 billion metric ton of Hydrogen that pours from the surface of the Sun each year.
See: "The Sun is a plasma diffuser that sorts atoms by mass," Physics of Atomic Nuclei 69 (2009) pages 1847-1856 or Yadernaya Fizika 69 (Russian, November 2006) number 11.
With kind regards,
Oliver K. Manuel
http://www.omatumr.com
Neutrons decay into hydrogen okay, but where do you come up with the idea neutrons are repulsive toward each other? Are there any experiments that confirm this?
"Neutron stars, in which gravity is opposed by neutron degeneracy pressure and short-range repulsive neutron-neutron interactions mediated by the strong force;"
http://en.wikiped...collapse
http://www.physic...ces.html
Consider:
http://www.google...+-manuel
http://www.google...+-manuel
It seems to be a well understood mathematical concept, but I'm afraid I have failed to discover a pure in situ experiment.
Thank you for the question.
Mass data for the 3,000 types of atoms that comprise the entire visible universe show clear evidence of repulsive interactions between neutrons in every atomic nucleus with two (2) or more neutrons.
See the "Cradle of the Nuclides" here: http://tinyurl.com/2otxps or
http://www.omatumr.com/Data/2000Data.htm" title="http://http://www.omatumr.com/Data/2000Data.htm" rel="nofollow" target="_blank">http://www.omatum...Data.htm
This finding was made in the spring semester of 2000 with help from five students in an advanced nuclear chemistry course (Chem 471: Special Topics in Nuclear Chemistry) at the University of Missouri-Rolla.
The finding has been reported in these papers and many others cited in the last one, and nobody - absolutely nobody (none, zero) in the nuclear, solar, or astrophysics community - has had the courage to suggest that our conclusion is wrong. To do that, the critic sends a note the editor asking that their criticism be published as a rebuttal.
01. http://xxx.lanl.g.../0411255
02. http://tinyurl.com/39kwoz or
http://www.omatumr.com/abstracts/jfeinterbetnuc.pdf" title="http://http://www.omatumr.com/abstracts/jfeinterbetnuc.pdf" rel="nofollow" target="_blank">http://www.omatum...tnuc.pdf
03. http://tinyurl.com/n99jvr or
http://www.spring...ak3lyrc/
04. http://tinyurl.com/mw7mhu or
http://www.spring...6685079/
.
.
.
.
05. http://arxiv.org/...609509v3
With kind regards,
Oliver K. Manuel
http://www.omatumr.com
Oliver K. Manuel: Thanks.
You have many good ideas and I find myself in agreement with most of your solar model. But I do have a question, in the excerpt below from one of your links refers to nuclide masses (neutrons?) as being in a high potential energy state.
One would think that the neutrons in a neutron star after a supernova collapse would be at a very low energy state. Wouldn't the pressure of a supernova explosion squeeze most of the heat energy out of the remaining neutrons just like a compressor squeezes heat energy out of a gas? (This heat energy would escape from the supernova by way of neutral neutrino radiation.)
The remaining neutron star would then be reheated by absorbing nearly all of the natural background of neutral neutrino radiation that strikes it. This heating would turn the surface neutrons into hydrogen gas recreating a star like our sun over the eons. This view would explain why nearly one-half of the neutrinos originating from the sun are missing. They are really neutral radiation that is reabsorbed by the neutrons in the sun.
All of this is explained in more detail starting on pages 7, also on 27 and 28 at the link below:
http://www.scribd...-Physics
--------------------------------------------------------------------------------
excerpt
" Nuclide masses showed repulsive n-n interactions, high potential energy for those in a neutron star, and a source for luminosity, neutrinos, and the carrier gas that sustains mass fractionation and an outflow of solar-wind hydrogen [12, 13].
05. http://arxiv.org/...609509v3
I take it you don't subscribe to "neutrino oscillation"?
Correct, I do not subscribe to neutrino oscillation.
Regardless of who, what, when, where, why, how the sun is producing neutrinos, from what I understand two aspects of neutrinos have been experimentally verified:
a. They have mass.
b. They oscillate.
Does anyone care to dispute?
DO SO IN 1,000,000,000,000,000,000,000,000 YEARS??
I don't think so.
To check the basic conservation laws of physics, double beta decay rates were measured where two electrons and two neutrinos are simultaneously emitted from nuclei like Se-82, Te-130 and Te-128.
For time spans up to 10^24 years, we saw no compelling evidence of neutrino oscillations [See: "Geochemical measurements of double-beta decay," J. Phys. G: Nucl. Part. Phys. 17 S221-S229 doi: 10.1088/0954-3899/17/S/024
http://www.iop.or...17/S/024
With kind regards,
Oliver K. Manuel
http://www.omatumr.com
Thank you for your kindness. You are correct in suggesting that neutrons were believed to be tightly bound in neutron stars - bound there by losing ~10% of their rest mass. I.e., the nuclear binding energy of each neutron was thought to be about +93 MeV.
Because of neutron repulsion, the nuclear binding energy of each neutron in a neutron star is about -(10 to 22) MeV. For the neutron star in the core of the Sun, the nuclear binding energy is now about -12 MeV.
This is explained further on the Naked Science Forum: http://tinyurl.com/lkj7zw
With kind regards,
Oliver K. Manuel
http://www.omatumr.com
OF AN ALPHA PARTICLE TO URANIUM NUCLEUS
With kind regards,
Oliver K. Manuel
http://www.omatumr.com
FUNDAMENTAL FORCE OVERLOOKED BY PHYSICISTS
Yes.
1. Measurements from 1960 to 1976 showed us that the Sun exploded axially 5 Gyr ago, ejected the material that now orbits it, and then reformed on the pulsar.
2. Close attention to existing data finally convinced us in 1983 that the interior of the Sun is mostly iron (Fe), not hydrogen (H), as expected in a supernova remnant.
3. Close attention to existing data finally convinced us in 2000 that repulsive interactions between neutrons in the mysterious energy source that powers the ball of iron that rises in the East eash morning and sets in the West each evening.
Yes. They only failed to consider the unrecognized repulsive force between neutrons that turns out to be the primary energy source that powers the cores of Sun, other stars, and galactic centers.
I will provide references if requested.
With kind regards,
Oliver K. Manuel
http://www.omatumr.com
BUT IGNORED - LIKE OTHER FINDINGS SINCE 1960
THAT EMBARRASSED NAS AND FUNDING AGENCIES
Yes. It was discovered in the spring of 2000 - with the help of five graduate students - in the rest mass data of all known nuclei in an Advanced Nuclear Chemistry course (Chem 471) that I taught at the University of Missouri-Rolla.
See CRADLE OF THE NUCLIDES: [url]http://tinyurl.com/2otxps[/url]
Neutron repulsion confirmed as energy source, Journal of Fusion Energy 20 (2001) pages 197-201: http://tinyurl.com/mw7mhu
Numerous other papers cited in: Fingerprints of a local supernova, in SPACE
EXPLORATION RESEARCH (Nova Science Publishers, Inc., Hauppauge, NY, in press, 38 pp, 2009); ISBN: 978-1-60692-264-4
http://arxiv.org/pdf/0905.0684
NAS has used its control over the budgets of NSF, DOE, NASA, NOA, etc. to hide, distort, or ignore repulsive interactions between neutrons and many other experimental findings since 1960 that compelled us to its discovery:
1. SPACE SCIENCE
The Sun gave birth to the solar system 5 Gyr ago by ejecting the material that now orbits it.
- a. The Sun reformed on the pulsar.
- b. Nearby material formed iron meteorites and iron cores of inner planets.
- c. The supernova envelope formed the giant gaseous Jovian planets.
- d. Rocky planets formed in layers, beginning with their iron cores.
- e. Iron is the most abundant element inside the Sun.
- See: http://tinyurl.com/359q3u
2. NUCLEAR SCIENCE
Repulsive neutron-neutron interactions in the solar core trigger reactions that produce solar luminosity, solar neutrinos, and SW-Hydrogen in exactly the proportions observed.
- a. Neutron-neutron interactions are strongly repulsive in all nuclei.
- b. Neutron-proton interactions are strongly attractive.
- c. Neutron-neutron and Coulomb-free proton-proton are symmetric.
- d. Hydrogen is a waste product, not fuel, of the Sun's nuclear furnace.
- e. Nuclear dissociation powers the Sun and sustains our lives.
- f. Solar neutrinos do not oscillate.
- See: [url]http://tinyurl.com/2otxps[/url]
COSMOLOGY
If this tiny corner of space is representative of the rest of the universe, then
- a. Competition between long-range gravitational forces and short-range repulsive forces between neutrons in compact massive objects at the cores of the Sun, other stars, and galaxies sustains their dynamic operation and releases Hydrogen to interstellar space.
- b. The universe may be finite and expanding as emissions from the first-formed neutron star(s) decay to the most dispersed form of nuclear matter, Hydrogen.
- c. The universe may be infinite and oscillating between:
- c, 1. Expansion as compact objects like that at the cores of stars and galaxies evaporate and release hydrogen to interstellar space, followed by
- c, 2. Contraction as the neutron stars evaporate away leaving less repulsive forces between neutrons to counter gravitational forces of attraction.
Despite opposition, All is well today
Oliver K. Manuel
http://www.omatumr.com
Repulsive forces between neutrons and most of the other conclusions posted above for SPACE SCIENCE and NUCLEAR SCIENCE are empirical facts.
Honest science requires us to accept what is - whether or not we understand (or imagine that we understand) why it is.
Scientists sometimes "invent" imaginary reasons for observations that prevent them from eventually finding the truth.
For example, alphabetically labeled neon components (Ne-A, Ne-B, Ne-C, Ne-D, Ne-E, etc.) for ordinary neon in various stages of mass fractionation [See: "The neon alphabet game", Proceedings of the 11th Lunar & Planetary Science Conference, volume 15, number 2 (1980) pages 879-899]
With kind regards,
Oliver K. Manuel
http://www.omatumr.com
Decades may lapse before we figure out an explanation for any observation. Here is one example during my research career.
1. OBSERVATIONS (1960s through 1990s): Iron meteorites are as old as "primitive" meteorites.
1. EXPLANATION (1991): Iron meteorites are material ejected directly from the core of the Sun. Molybdenum isotopes made by various nuclear reactions are still today, 5 x 10^9 yrs (5 Gyr) later are still not homogenized [Qi-Lu, Doctoral Dissertation, The University of Tokyo, 1991]
http://tinyurl.com/mwsevr
2. OBSERVATIONS (1960s through 1980s): Isotopes of many elements in meteorite inclusions, in the solar wind, in solar flares, in the Earth, and in other planets revealed evidence of severe mass fractionation as seen, for example, in Ne isotopes over the range of 0.1 < Ne-20/Ne-22 < 15.
3. OBSERVATION (1980s to 2000s): The Sun is mostly iron and cannot shine. But the Sun continues to shine.
With kind regards,
OM
2. EXPLANATION (1983): The Sun is a plasma diffuser that sorts atoms by mass. http://arxiv.org/.../0609509
3. EXPLANATION (2000): Neutron repulsion is the primary source of energy in the cores of stars and galaxies. http://arxiv.org/.../0511379
With kind regards,
Oliver K. Manuel
http://www.omatumr.com
I believe your observations constitute a validation of existing theory, while you think they could be used to improve models. The difference in opinion could be resolved by comparing the predictions of the appropriate theories with your observations. For someone familiar with the data and existing theories, it should not be difficult to at least speculate about reasonable explanations of the observations.
Molybdenum isotopes in massive pieces of iron that fall from the sky are not still throughly mixed today [Qi-Lu, Doctoral Dissertation, The University of Tokyo, 1991], 5 x 10^9 yrs (5 Gyr) after the iron was ejected from the core of a supernova?
http://tinyurl.com/mwsevr
Don't forget the imaginary interstellar cloud of existing theory that supposedly
1. Collapsed to form the solar system,
2. Differentiated chemically to form iron meteorites,
3. Left the isotopes of Molybdenum unmixed, all this
4. Before Pd-107 and other short-lived nuclides decayed away.
With kind regards,
Oliver K. Manuel
http://www.omatumr.edu
http://www.omatum...Data.htm