"strange quark stars."

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Expand view Topic review: "strange quark stars."

by harry » Mon May 22, 2006 1:24 pm

Hello All

http://glast.gsfc.nasa.gov/


The Gamma-ray Large Area Space Telescope (GLAST) will open this high-energy world to exploration and help us to answer these questions. With GLAST, astronomers will at long last have a superior tool to study how black holes, notorious for pulling matter in, can accelerate jets of gas outward at fantastic speeds. Physicists will be able to study subatomic particles at energies far greater than those seen in ground-based particle accelerators. And cosmologists will gain valuable information about the birth and early evolution of the Universe.

For this unique endeavor, one that brings together the astrophysics and particle physics communities, NASA is teaming up with the U.S. Department of Energy and institutions in France, Germany, Japan, Italy and Sweden. General Dynamics C4 Systems has been chosen to build the spacecraft. The launch is scheduled for August of 2007.

I cannot wait for the information that will come from the GLAST.

I have been waiting for this type of info for decades.

by harry » Mon May 22, 2006 12:51 pm

Hello qev

Found this link, its worth relating the properties of comapcted stars to blackholes.

http://www.jb.man.ac.uk/news/CircinusX-1/
Neutron Star Imitates Black Hole.htm
You may have to google this one.
Since the 1970's astronomers have known that Circinus X-1 produces radio waves as well as X-rays. A large 'nebula' of radio emission lies around the X-ray source. Within the nebula lies the new-found jet of radio-emitting material thought to be associated with an accretion disk of material falling in towards the neutron star. In Circinus X-1 its likely that the accretion disk varies with the 17-day cycle, being at its most intense when the stars are almost touching at the closest point in the orbit. It is then that the jets of matter appear to be ejected from the system.

Jets with speeds of ~ 99% (see note *) of the speed of light have been observed being emitted from the the regions around black holes in our own galaxy and have occasionally been seen emanating from neutron stars, but never before has an ultra-relativistic jet been seen that did not originate from a black hole region. The team has shown that the jets in Circinus X-1 are travelling at 99.8% of the speed of light. This is the fastest outflow seen from any object in our Galaxy, and matches the fastest jets powered by supermassive black holes at the heart of distant galaxies. Whatever process accelerates the jets to near the speed of light, it cannot therefore rely on the special properties of a black hole. "The key process must be one common to both black holes and neutron stars" said Kinwah Wu, formerly of the University of Sydney, now at University College London in the UK.

http://arxiv.org/abs/astro-ph/0305252
http://arxiv.org/abs/astro-ph/0305261
A Jet is a Jet, Big or Small Scale Invariance of Black Hole Jets.htm

by Qev » Sun May 21, 2006 3:44 pm

harry wrote:Hello All

Qev you are quite right in what you say and with bosons being able to occupy the same space.

A theoretical preon star would be denser than a neutron star and would not be lighter. This part of your writing I do not understand.
A preon star is generally thought to be much lighter than neutron stars, but the material that makes them up would be much denser. Very much like a one kilogram block of lead is much more dense than a thousand kilograms of water, but is smaller in mass.
As for a black hole we can only assume what is happening inside from the progressive compaction of subatomic particals. I cannot see and infinite point in space. Maybe its just me until I have more info.
True enough! All we currently have to go on is General Relativity, and it tells us that things collapse to an infinity. Needless to say, nobody really likes that result very much. :lol:
Other than that your writing is great, I take my hut off.
Thank you! :D

by harry » Sun May 21, 2006 9:46 am

Hello All

Qev you are quite right in what you say and with bosons being able to occupy the same space.

A theoretical preon star would be denser than a neutron star and would not be lighter. This part of your writing I do not understand.

As for a black hole we can only assume what is happening inside from the progressive compaction of subatomic particals. I cannot see and infinite point in space. Maybe its just me until I have more info.

Other than that your writing is great, I take my hut off.

by harry » Sun May 21, 2006 9:32 am

Hello All

Qev you are quite right in what you say and with bosons being able to occupy the same space.

A theoretical preon star would be denser than a neutron star and would not be lighter. This part of your writing I do not understand.

As for a black hole we can only assume what is happening inside from the progressive compaction of subatomic particals. I cannot see and infinite point in space. Maybe its just me until I have more info.

Other than that your writing is great, I take my hut off.

by Qev » Sun May 21, 2006 3:06 am

harry wrote:Hello All

qev said
I'm afraid it's not possible to have the mass of the sun compressed into an object 300mm in diameter and have it remain stable. Once the total mass of the Sun gets compacted within it's own Schwartzchild radius (which is 3km), you have a black hole; nothing can prevent its further collapse.


In this day an age i would not limit my thinking.
Well... that outcome is predicted by General Relativity, and I haven't seen anyone be able to poke holes in its predictions yet, not at the macroscopic scale. The problem is, once an object's mass falls within its own Schwartzchild radius, the escape velocity exceeds the speed of light. No force can hold up under that kind of gravitational field, as everything in the universe is governed by the light-speed limit (that we know of)... including all of the fundamental forces, which are what give structure and stability to matter.
Let us think outside the circle and look for the answer. I need someone to look at the possiblities. This 300 mm ball is theoretical and would probably require a density of about 10^18 to 10^30
compared to a neutron star density of about 10^18 or there abouts.

So if we multiply 10^30 by 300mm we get some mad number which is greter than the width of our sun.
Well, if you're looking for density, it's total mass divided by volume. For the object you're proposing, it would be on the order of 1.4x10^32 kg/m^3, which is an utterly insanely high density, far beyond anything that could be stable under its own self-gravity. Remember that a neutron star of much lower density than this will collapse into a black hole.
Even if it were somehow stable, it would still be inside an event horizon, and would technically be a black hole; it would behave exactly the same.
Maybe be so, but! what is the steps from a neutron core to a blackhole.
Well, there may be the 'quark star' stage, which has an estimated core density around 3x10^18 kg/m^3, which is roughly ten times more dense than the average neutron star's core density. But this is nowhere near the sorts of densities you're proposing. :)
A black hole is a state of matter that has the basic degenerated particals that make up all matter.

Its not a hole as so to speak of. But! just a massive compacted degereated particals.

I would not classify it as a singularity where all particals take up one point in space and time. I would assume that no two particals can ocupy the same space at the same time.
Actually, that's the problem: we just don't know what the inside of a black hole looks like, or what happens to the matter that falls into it. Under General Relativity one gets a singularity, a point of infinite density and gravity, which physicists would like to avoid somehow, if they could. Until we have a decent working theory of quantum gravity, we'll never really be able to answer that question. It could very well be that all of the mass gets compressed down into a single 'super particle' or something equally bizarre. Who knows?

Also, some types of particles are quite happy to share the same place at the same time, and are called bosons. These particles have whole integer units of quantum spin. The other group, the fermions, have half-integer quantum spins, and must obey the Pauli Exclusion Principle, forbidding any two of them from sharing the exact same quantum state.
Sorry my computer has not been fixed yet, and cannot search for preon stars and so on. Can someone do that and look at the possible size of a preon star in theory.
Preon stars are estimated to have densities exceeding 10^23kg/m^3. They're also much lighter than neutron stars, being generally thought to mass up to 100 times the mass of the Earth. From what I've read, if these things can exist, they would do so at the very edge of collapsing into a black hole, since at those densities the radius of the object is almost equal to its own Schwartzchild radius. I imagine these things don't hang around very long, if they even exist at all. Preons, as a theory, aren't terribly widely supported.

by harry » Sat May 20, 2006 11:58 pm

Hello All

qev said
I'm afraid it's not possible to have the mass of the sun compressed into an object 300mm in diameter and have it remain stable. Once the total mass of the Sun gets compacted within it's own Schwartzchild radius (which is 3km), you have a black hole; nothing can prevent its further collapse.


In this day an age i would not limit my thinking.

Let us think outside the circle and look for the answer. I need someone to look at the possiblities. This 300 mm ball is theoretical and would probably require a density of about 10^18 to 10^30
compared to a neutron star density of about 10^18 or there abouts.

So if we multiply 10^30 by 300mm we get some mad number which is greter than the width of our sun.

Even if it were somehow stable, it would still be inside an event horizon, and would technically be a black hole; it would behave exactly the same.
Maybe be so, but! what is the steps from a neutron core to a blackhole.

--------------------------------------------------------------------------
A black hole is a state of matter that has the basic degenerated particals that make up all matter.

Its not a hole as so to speak of. But! just a massive compacted degereated particals.

I would not classify it as a singularity where all particals take up one point in space and time. I would assume that no two particals can ocupy the same space at the same time.


Sorry my computer has not been fixed yet, and cannot search for preon stars and so on. Can someone do that and look at the possible size of a preon star in theory.

by BMAONE23 » Sat May 20, 2006 3:57 pm

If you take into consideration the fact that mass is necessary to sustain a Black Hole, the fact that most black holes require many solar masses to evolve in the first place, and the most massive contain m(b)illions of solar masses: given the approximate size of the Black Hole mass, what would be the size of 1 solar mass at that compression?

by Qev » Sat May 20, 2006 1:33 pm

I'm afraid it's not possible to have the mass of the sun compressed into an object 300mm in diameter and have it remain stable. Once the total mass of the Sun gets compacted within it's own Schwartzchild radius (which is 3km), you have a black hole; nothing can prevent its further collapse.

Even if it were somehow stable, it would still be inside an event horizon, and would technically be a black hole; it would behave exactly the same.

by harry » Fri May 19, 2006 10:31 pm

Hello Orin

Thanks Orin

I think there is one more step before a blackhole is formed.

The preons that make up quarks are more compacted to form the theoretical preon star.

You can put our sun in a ball 300mm dia.

by orin stepanek » Fri May 19, 2006 1:44 pm

Harry! Here is another link to your quark stars.
http://archives.cnn.com/2002/TECH/space ... index.html
Supposedly they are in a state between that of a neutron star and a black hole. If quarks are the building blocks of matter than there ought to be more of them out there.
Orin

by harry » Sun May 07, 2006 1:32 pm

Hello All

Cosmologists put compact stars, quarks to preon (theory) and black holes as part of dark matter.

They also say that 99% of all matter is in Plasma.

What do you think.

hi

by ta152h0 » Fri May 05, 2006 9:01 pm

makc

"pass the ice cold one " has become part of my signature. I don't drink, i just find humor in this.

by harry » Fri May 05, 2006 10:59 am

Hello All

Even if I study cosmology for another 10 years I will still be knowing very little.

As I read more I feel I know less.

Why is that?

Darn,,,,,,,,,,,,,I better read less and know more.

by makc » Fri May 05, 2006 6:30 am

tah, I think you drink too much.

so...............

by ta152h0 » Thu May 04, 2006 9:55 pm

Soooooooooooo Harry,
that makes you the " Chief Understander "
pass me an ice cold one :)

by harry » Wed May 03, 2006 5:56 am

Hello Pete

I understand,,,,,,smile,,,,,,,,,,,, but it sounds quarky to me.

I just added that info for others to understand.

by Pete » Tue May 02, 2006 2:37 pm

Right, harry, not all "quarks" are "strange quarks". Nevertheless, "strange quark star", "quark star", and "strange star" are synonymous terms according to the "Quark Star" Wikipedia article and the external links found within.

by harry » Tue May 02, 2006 1:52 pm

Hello Qev

No,,,,,,,,,,,,,,,Strange as it may seem, but strange quarks are different.
As a matter of fact there is six know quarks.

see link

http://hyperphysics.phy-astr.gsu.edu/hb ... rk.html#c6

Why "Quark"?

The name "quark" was taken by Murray Gell-Mann from the book "Finnegan's Wake" by James Joyce. The line "Three quarks for Muster Mark..." appears in the fanciful book. Gell-Mann received the 1969 Nobel Prize for his work in classifying elementary particles.

Quarks and Leptons are the building blocks which build up matter, i.e., they are seen as the "elementary particles". In the present standard model, there are six "flavors" of quarks. They can successfully account for all known mesons and baryons (over 200). The most familiar baryons are the proton and neutron, which are each constructed from up and down quarks. Quarks are observed to occur only in combinations of two quarks (mesons), three quarks (baryons), and the recently discovered particles with five quarks (pentaquark).

The up and down quarks are the most common and least massive quarks, being the constituents of protons and neutrons and thus of most ordinary matter.

In 1947 during a study of cosmic ray interactions, a product of a proton collision with a nucleus was found to live for much longer time than expected: 10-10 seconds instead of the expected 10-23 seconds! This particle was named the lambda particle (Λ0) and the property which caused it to live so long was dubbed "strangeness" and that name stuck to be the name of one of the quarks from which the lambda particle is constructed. The lambda is a baryon which is made up of three quarks: an up, a down and a strange quark.


In 1974 a meson called the J/Psi particle was discovered. With a mass of 3100 MeV, over three times that of the proton, this particle was the first example of another quark, called the charm quark. The J/Psi is made up of a charm-anticharm quark pair.

Convincing evidence for the observation of the top quark was reported by Fermilab 's Tevatron facility in April 1995. The evidence was found in the collision products of 0.9 TeV protons with equally energetic antiprotons in the proton-antiproton collider


In 1977, an experimental group at Fermilab led by Leon Lederman discovered a new resonance at 9.4 GeV/c^2 which was interpreted as a bottom-antibottom quark pair and called the Upsilon meson

by Qev » Mon May 01, 2006 3:23 pm

Here is a link to a wikipedia article discussing the theoretical class of particles known as preons. Currently, this class of theories has very little support, as none of the theories are able to predict observational data that has been collected.

Regarding quark stars and strange quark stars, I believe the two terms are synonymous; 'quark star' is just one word shorter to say. :) I've also heard them termed just 'strange stars' as well.

by harry » Mon May 01, 2006 6:02 am

Hello Kovil

Thanks for the heads up.

by harry » Mon May 01, 2006 5:57 am

hello all

I had this link and found it

http://antwrp.gsfc.nasa.gov/apod/ap020414.html

I hope its not a repeat

These strange stars are coming out of the woodwork
Now we know of
normal stars as so to speak
Brown dwarf stars
white dwarf star
neutron stars
quark stars
strange quark stars

Preon stars (theory),,,,,,,,,,,,,,,,,,has anybody got info on this cuty.

leading up to small black holes,,,,,,,,,,,,,,stella black holes
leading up to black holes of a million or so sun mass
leading up to super black holes a few billion sun mass.

leading up to wopper black holes in a galaxy far far away.

This is so interesting its making my head spin.

by harry » Wed Apr 26, 2006 6:17 am

Hello All

With a head cold I copied thus info.
I'm off to bed

Ultra dense Plasma matter

http://plasmadictionary.llnl.gov/ter...age=list&ABC=Q
Term: Quark-gluon plasma
Definition:
"A state of matter in which quarks and gluons, the fundamental constituents of matter, are no longer confined within the dimensions of the nucleon, but free to move around over a volume in which a high enough temperature and/or density prevails. This type of plasma has recently, 2/2000, been observed indirectly by the European laboratory for particle physics, CERN. These plasmas result in effective quark masses which are much larger than the actual masses. Calculations for the transition temperature to this new state give values between 140 and 180 MeV. This is more than 10,000 times the nominal fusion plasma temperature of 10keV. 150 MeV is the characteristic energy of a particle in a plasma at roughly 1.5 trillion Kelvin. This corresponds to an energy density in the neighborhood of seven times that of nuclear matter. Temperatures and energy densities above these values existed in the early universe during the first few microseconds after the Big Bang. "


http://columbia-physics.net/faculty/gyulassy_main.htm

Professor: Miklos Gyulassy

Research
quote:"I head the nuclear theory group at Columbia. Our work concentrates on the physics of ultra-dense nuclear matter, called the quark-gluon plasma. Current experiments at the Relativistic Heavy Ion Collider RHIC at BNL require the development of detailed parton/ hadron transport theory in order to interpret the data and to test specific signatures that can reveal the physical properties of this new state of matter. We have developed new techniques to solve ultra-relativistic non-linear Boltzmann equations and relativistic hydrodynamics to study collective flow signatures, such as elliptic transverse flow at RHIC. In addition, these transport models are used to predict pion interferometry correlations that probe the global freeze-out space-time geometry of high energy nuclear reactions. Recently we concentrate on the problem of non-abelian radiative energy loss and its application as a novel tomographic tool to study the density evolution in the expanding gluon plasma on times scales ~10^-23 sec. We predicted that high transverse momentum jets of hadrons produced in nuclear reactions should be strongly quenched by radiative energy loss induced by the high opacity of the produced plasma. This prediction has been recently confirmed by the PHENIX and STAR experiments at RHIC, and we have deduced from the quenching pattern that gluon densities about 100 times greater than in ground state nuclei have been attained in Au+Au reactions at Ecm = 200 AGeV. At such high densities matter is predicted via lattice QCD to be in the deconfined phase. We continue to refine and extend the theory of jet tomography in order to predict the quenching pattern of heavy quarks as well as high pT correlations of monojets. Another area of interest is the dynamics of baryon number transport and hyperonization at RHIC. Preliminary data provide possible evidence of novel topological gluon junction dynamics that we first tested on data at lower SPS/CERN energies."

by harry » Mon Apr 10, 2006 1:47 am

Hello Kovil

Thank you mate.

Love this info.

MHD and extragalactic jets

by kovil » Sun Apr 09, 2006 3:10 pm

Here's another good one on MHD accelerating electrons in galactic jets.


Lepton Acceleration by Relativistic Collisionless Magnetic Reconnection

D. A. Larrabee

R. V. E. Lovelace and M. M. Romanova

ABSTRACT

We have calculated self-consistent equilibria of a collisionless relativistic electron-positron gas in the vicinity of a magnetic X-point. For the considered conditions, pertinent to extragalactic jets, we find that leptons are accelerated up to Lorentz factors 0 = eB0L2/mc2 1, where B0 is the typical magnetic field strength, E0/B0, with E0 the reconnection electric field, L is the length scale of the magnetic field, and 12. The acceleration is due to the dominance of the electric field over the magnetic field in a region around the X-point. The distribution function of the accelerated leptons is found to be approximately dn/d -1 for 0. The apparent distribution function may be steeper than -1 due to the distribution of 0 values and/or the radiative losses. Self-consistent equilibria are found only for plasma inflow rates to the X-point less than a critical value.

Subject headings: acceleration of particlesgalaxies: jetsmagnetic fieldsMHDplasmas

1. INTRODUCTION

The observed radiation of most large-scale extragalactic jets is due to incoherent synchrotron radiation. In a number of sources, M87 and 3C 273, for instance, the radiation lifetime of the electrons (and possibly positrons) is much less than the transit time from the central source (Felten 1968). Thus, there must be mechanisms for the electron "reacceleration."

Several mechanisms have been proposed to account for the reacceleration of the electrons. These include the Fermi mechanism of particle acceleration (Pacholczyk & Scott 1976), Fermi acceleration in shock waves (Krimsky 1977; Axford, Leer, & Skadron 1978; Bell 1977, 1978; Blandford & Ostriker 1978), stochastic electric field acceleration (Eilek & Hughes 1990), and whistler-wave acceleration (Melrose 1974). The effectiveness of the Fermi mechanism and stochastic fields in accelerating electrons is unknown (Blandford & Eichler 1987; Eilek & Hughes 1990; Jones & Ellison 1991). Resistive tearing has been discussed as a means of producing neutral layers that can accelerate electrons (Königl & Choudhuri 1985; Choudhuri & Königl 1986). Reconnection as a mechanism for accelerating electrons has been discussed by a number of authors (Blandford 1983; Begelman, Blandford, & Rees 1984; Browne 1985; Ferrari 1984; Norman 1985; Kirchner 1988; Lesch 1991; Romanova & Lovelace 1992). The acceleration of electrons by long-wavelength electromagnetic waves trapped in the boundary layer of a jet has been discussed by Bisnovatyi-Kogan & Lovelace (1995).

The reconnection of magnetic fields at a neutral point as described by magnetohydrodynamics (MHD) has been studied extensively. It has been shown that the neutral lines can evolve into current sheets (Syrovatskii 1971). Resistive MHD simulations of reconnection by Biskamp (1986) show a strong tendency to form current sheets.

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