Jets Big and Small: Understanding the Universe through High-Energy Emissions

[Sundance]

Hello

Jets Big and Small maybe the key to understanding the universe.

On a side issue from the Quasars and cosmology post, since the file is locked.

Response to Neried

I understand your logic, your good.
But! You said

Finally, it would seem that you, Sundance, may not be aware of just how enormous and compelling the published papers on quasars are, and the vast quantity of high quality observations on which the contemporary 'unified AGN model' is built (I gave a short para summary in post#84). If you'd like to explore that more, I'd be happy to help you ... why not start a new thread on it?

I'm quite awear of the huge and upto date papers on quasars, so called black holes, degenerate matter, jet formation etc. As for the unified AGN model, if History proves me write, unification is only temporary if that.

As for Jets Big and Small

http://arxiv.org/abs/0812.0021
Gamma-ray Burst 080319B: Evidence for Relativistic Turbulence, Not Internal Shocks

Authors: Pawan Kumar, Ramesh Narayan
(Submitted on 1 Dec 2008)

Abstract: We show that the excellent optical and gamma-ray data available for GRB 080319B rule out the internal shock model for the prompt emission. The data instead point to a model in which the observed radiation was produced close to the deceleration radius ($\sim10^{17}$ cm) by a turbulent source with random Lorentz factors $\sim10$ in the comoving frame. The optical radiation was produced by synchrotron emission from relativistic electrons, and the gamma-rays by inverse Compton scattering of the synchrotron photons. The gamma-ray emission originated both in eddies and in an inter-eddy medium, whereas the optical radiation was mostly from the latter. Therefore, the gamma-ray emission was highly variable whereas the optical was much less variable. The model explains all the observed features in the prompt optical and gamma-ray data of GRB 080319B. We are unable to determine with confidence whether the energy of the explosion was carried outward primarily by particles (kinetic energy) or magnetic fields. Consequently, we cannot tell whether the turbulent medium was located in the reverse shock (we can rule out the forward shock) or in a Poynting-dominated jet.

The question that most ask is where and how does the jet form.

The properties of jets are studied in depth and as time passes our abilty to study them in depth increases. Its fun and games for the next few years.

 

[Nereid]

I'm not at all sure why you think jets "maybe the key to understanding the universe" Sundance.

Surely they are, in the first instance, an astrophysics puzzle (not a cosmology one)?

Also, while understanding jets in AGNs is indeed a most interesting research topic, I don't see how a detailed account of how they form could challenge the unified AGN model.

Perhaps a mentor could move this thread to the Astrophysics section?

 

[Sundance]

Hello Neried

Jets are part of the process that eject matter out.

The interesting part is that it come out as degenerate matter mostly.

Therefore forms part of a recycling process.

There are varies mechanism for Jets, hre is one:

Relativistic poynting jets
http://arxiv.org/find/all/1/all:+AND+jets+AND+relativistic+Poynting/0/1/0/all/0/1

The papers do not give the specific location of the formation of the jets
and the trigger.

 

[granpa]

most of the matter expelled by the jets is DEGENERATE?! I've never heard of that before. I'd love to read more about that.

is it mostly metallic hydrogen?

 

[Sundance]

Hello Grandpa

Read the link to understand jets.

 

[Nereid]

Hello Neried

Jets are part of the process that eject matter out.

The interesting part is that it come out as degenerate matter mostly.

Therefore forms part of a recycling process.

There are varies mechanism for Jets, hre is one:

Relativistic poynting jets
http://arxiv.org/find/all/1/all:+AND+jets+AND+relativistic+Poynting/0/1/0/all/0/1

The papers do not give the specific location of the formation of the jets
and the trigger.

(bold added)

Interesting material, Sundance.

Like granpa, I had never heard of the jets being degenerate matter, so I read the first paper you provided a link to, and skimmed several others. It seems that none of the papers mentions "degenerate matter".

Would you please clarify?

In particular, in which paper(s) did you read that the jets are composed (mostly) of degenerate matter?

 

[granpa]

Hello Grandpa

Read the link to understand jets.

I'm not a 'Grandpa'. I'm just a 'granpa'. that's kinda the whole point of my handle.

 

[Sundance]

Hello Granpa

Sorry for the "d"

Neried I will get back to you.
This is the link That I'm also reading.

http://adsabs.harvard.edu/cgi-bin/nph-basic_connect?qsearch=Degenerate+matter+black+holes&version=1

The transition of matter to compact matter that is found in black holes takes various transitions. Neutron matter maybe the first, followed by other exotic matter.

http://adsabs.harvard.edu/cgi-bin/nph-basic_connect?qsearch=Degenerate+matter+black+holes&version=1

Sorry for being quick, I will be back.

 

[Sundance]

Hello

This maybe of interest

http://arxiv.org/abs/0811.2034
Transonic properties of the accretion disk around compact objects

Authors: Banibrata Mukhopadhyay
(Submitted on 13 Nov 2008)

Abstract: An accretion flow is necessarily transonic around a black hole. However, around a neutron star it may or may not be transonic, depending on the inner disk boundary conditions influenced by the neutron star. I will discuss various transonic behavior of the disk fluid in general relativistic (or pseudo general relativistic) framework. I will address that there are four types of sonic/critical point possible to form in an accretion disk. It will be shown that how the fluid properties including location of sonic points vary with angular momentum of the compact object which controls the overall disk dynamics and outflows.

 

[Nereid]

Sundance, I am quite confused by all these references!

Although I have not checked them all - not even read all the abstracts yet - there seems to be nothing in here of relevance to degenerate matter in jets, which is after all the topic of this thread.

Can you please clarify?

This maybe of interest

Yes, it is interesting ... but so are, in their own ways, the thousands of Astrophysics, General Relativity and Quantum Cosmology, High Energy Physics - Phenomenology, and High Energy Physics - Theory papers published every year.

Would you please take some time, gather your thoughts, and write a succinct post on the area you are (apparently) interested in?

 

[Sundance]

G'day Neried

Maybe this will help

Accretion flow transonic
http://arxiv.org/find/all/1/all:+AND+transonic+AND+Accretion+flow/0/1/0/all/0/1

Than again what do you think degenerate matter is?

http://arxiv.org/abs/0811.2034
Transonic properties of the accretion disk around compact objects

Authors: Banibrata Mukhopadhyay
(Submitted on 13 Nov 2008)

Abstract: An accretion flow is necessarily transonic around a black hole. However, around a neutron star it may or may not be transonic, depending on the inner disk boundary conditions influenced by the neutron star. I will discuss various transonic behavior of the disk fluid in general relativistic (or pseudo general relativistic) framework. I will address that there are four types of sonic/critical point possible to form in an accretion disk. It will be shown that how the fluid properties including location of sonic points vary with angular momentum of the compact object which controls the overall disk dynamics and outflows

.


and

http://arxiv.org/abs/0812.3401
The X-ray Jets of Active Galaxies

Authors: D.M. Worrall (University of Bristol)
(Submitted on 17 Dec 2008)

Abstract: Jet physics is again flourishing as a result of Chandra's ability to resolve high-energy emission from the radio-emitting structures of active galaxies and separate it from the X-ray-emitting thermal environments of the jets. These enhanced capabilities have coincided with an increasing interest in the link between the growth of super-massive black holes and galaxies, and an appreciation of the likely importance of jets in feedback processes. I review the progress that has been made using Chandra and XMM-Newton observations of jets and the medium in which they propagate, addressing several important questions, including: Are the radio structures in a state of minimum energy? Do powerful large-scale jets have fast spinal speeds? What keeps jets collimated? Where and how does particle acceleration occur? What is jet plasma made of? What does X-ray emission tell us about the dynamics and energetics of radio plasma/gas interactions? Is a jet's fate determined by the central engine?

and

http://arxiv.org/abs/0810.0923
Dynamics of black holes

Authors: Sean A. Hayward
(Submitted on 6 Oct 2008)

Abstract: This is a review of current theory of black-hole dynamics, concentrating on the framework in terms of trapping horizons. Summaries are given of the history, the classical theory of black holes, the defining ideas of dynamical black holes, the basic laws, conservation laws for energy and angular momentum, other physical quantities and the limit of local equilibrium. Some new material concerns how processes such as black-hole evaporation and coalescence might be described by a single trapping horizon which manifests temporally as separate horizons.

This process of forming jets will be the most important process to understand.

It will explain the phase changes in star formation and the various forms of galaxy evolution.

 

[Nereid]

G'day Neried

Erm, the name is Nereid, if you please.

Maybe this will help

Accretion flow transonic
http://arxiv.org/find/all/1/all:+AND+transonic+AND+Accretion+flow/0/1/0/all/0/1

What, may I ask, Sundance, do you think this may help with?

I am still at a loss as to what you trying to say, in terms of jets, degenerate matter, and astrophysics.

Can you clarify please? In your own words.

Than again what do you think degenerate matter is?

In the material that you've provided links to, that I've read so far, three/four types of degenerate matter have been mentioned (if there are others, please identify them exactly):

* electron degeneracy, as in white dwarf stars (below a thin atmosphere)

* nuclear degeneracy, as in neutron stars (below a thin crust)

* hypothetical degenerate states involving quarks or excited hadronic states (e.g. 'strange matter'), in the cores of neutron stars.

* neutrino degeneracy, a hypothetical state of matter.

AFAICS, no paper even hints at any of these states being found in jets!

[...]
.


and

http://arxiv.org/abs/0812.3401
The X-ray Jets of Active Galaxies

Authors: D.M. Worrall (University of Bristol)
(Submitted on 17 Dec 2008)




and

http://arxiv.org/abs/0810.0923
Dynamics of black holes

Authors: Sean A. Hayward
(Submitted on 6 Oct 2008)




This process of forming jets will be the most important process to understand.

It will explain the phase changes in star formation and the various forms of galaxy evolution.

Why do you think this, if I may ask?

AFAICS, none of the papers you've cited point to this conclusion.

Besides, I don't know what you are referring to in "the phase changes in star formation"; could you elaborate please?

 

[Sundance]

Hello Nereid

Am I do unstand that you do not understand star formation or jet formation and the probable formation of black holes from transient phase changes.

As for degenerate matter it seems that you have partly covered its meaning and properties.

As for phase changes in matter. Tell me what you think.

Also explain to me what matter is found in jets.

If I'm going to go into depth in this topic, I want to know what you know.

I will have more time later.

 

[Nereid]

The matter density of the bipolar jets observed in a range of astronomical objects, from YSOs (young stellar objects, the last stage of the collapse of the star's natal cloud) to AGNs, is extremely low, by our here-on-Earth standards ... a good vacuum to one so hard we can't make it in an Earthly lab!

No degenerate states of matter are known for such low densities, esp when you also consider that the temperature of the matter in the jets (measured suitably) is high.

The jets obviously contain electrons - that's what makes them visible, the synchrotron radiation - and protons; many jets also contain nuclei of heavier elements (than H), such as He.

May I ask, again, from where you are getting the idea that jets contain degenerate matter?

I've https://www.physicsforums.com/showthread.php?p=2036987#post2036987" to another one of your posts, from a month or so ago; it seems that you are conflating two quite different meanings of the term 'degenerate' that you have found in some papers ...

 

[Sundance]

Nereid

What do you think the compact matter is made from?

If its made from degenerate made?

As we observe a Neutron star forming than evolving into ultra high density matter, that some call black holes.

Than what do you think would be ejected from such compact matter?

How are you reading these papers?


Heres another


http://arxiv.org/abs/0811.0874
Solitons and vortices in an evolving Bose-Einstein condensate

Authors: Shi-Jie Yang, Quan-Sheng Wu, Shiping Feng, Yu-Chuan Wen, Yue Yu
(Submitted on 6 Nov 2008)

Abstract: Spatiotemporal evolution of a confined Bose-Einstein condensate is studied by numerically integrating the time-dependent Gross-Pitaevskii equation. Self-interference between the successively expanding and reflecting nonlinear matter waves results in spiral atomic density profile, which subsequently degenerates into an embedding structure: The inner part preserves memory of the initial states while the outer part forms a sequence of necklacelike rings. The phase plot reveals a series of discrete concentric belts. The large gradients between adjacent belts indicate that the ring density notches are dark solitons. In the dynamical process, a scenario of vortex-antivortex pairs are spontaneously created and annihilated, whereas the total vorticity keeps invariant.

Keep reading

http://arxiv.org/abs/0810.4138
Leptoquarks and Neutrino Masses at the LHC

Authors: Pavel Fileviez Perez, Tao Han, Tong Li, Michael J. Ramsey-Musolf
(Submitted on 22 Oct 2008)

Abstract: The properties of light leptoquarks predicted in the context of a simple grand unified theory and their observability at the LHC are investigated. The SU(5) symmetry of the theory implies that the leptoquark couplings to matter are related to the neutrino mass matrix. We study the resulting connection between neutrino masses and mixing parameters and the leptoquark decays, and show that different light neutrino hierarchies imply distinctive leptoquark decay signatures. We also discuss low-energy constraints implied by searches for charged lepton flavour violation, studies of meson decays, and electroweak precision data. We perform a detailed parton-level study of the leptoquark signals and the Standard Model backgrounds at the LHC. With the clean final states containing a di-lepton plus two jets, the QCD production of the leptoquark pair can be observed for a leptoquark mass of one TeV and beyond. By examining the lepton flavor structure of the observed events, one could further test the model predictions related to the neutrino mass spectrum. In particular, b-flavor tagging will be useful in distinguishing the neutrino mass pattern and possibly probing an unknown Majorana phase in the Inverted Hierarchy or the Quasi-Degenerate scenario. Electroweak associated production of the leptoquark doublet can also be useful in identifying the quantum numbers of the leptoquarks and distinguishing between the neutrino mass spectra, even though the corresponding event rates are smaller than for QCD production. We find that with only the clean channel of mu+ E_T jets, one could expect an observable signal for a leptoquark masses of about 600 GeV or higher.

and

http://arxiv.org/abs/0708.2263
The SN 1987A Link to Others and Gamma-Ray Bursts

Authors: John Middleditch
(Submitted on 16 Aug 2007 (v1), last revised 6 Feb 2008 (this version, v8))

Abstract: Early measurements of SN 1987A can be interpreted in light of a beam/jet (BJ), with a collimation factor >10,000, which impacted polar ejecta (PE) to produce the "Mystery Spot" (MS), ~24 lt-d away. Other details of SN 1987A suggest that it came from a merger of 2 stellar cores of a common envelope (CE) binary, i.e. a "double degenerate" (DD) SN. Even having to penetrate the CE, the BJ may have caused a long-soft (l)GRB upon hitting the PE, thus DD can produce lGRBs. Because DD must be the dominant merger/SN mechanism in elliptical galaxies (EGs), where only short, hard GRBs (sGRBs) have been observed, DD without CE or PE must also produce sGRBs, and thus NS-NS mergers may not make GRBs as we know them, and/or be as common as previously thought. Millisecond pulsars (MSPs) in the non-core-collapsed globular clusters are also 99% DD-formed from WD-WD merger, consistent with their 2.10 ms minimum spin period, the 2.14 ms signal seen from SN 1987A, and sGRBs offset from the centers of EGs. The details of Ia's suggest that these are also DD, and the total thermonuclear disruption paradigm is now in serious doubt as well, a cause for concern in Ia Cosmology, because Ia's will appear to be Ic's when viewed from their DD merger poles, given sufficient matter above that lost to core-collapse. As a DD SN, 1987A appears to be the Rosetta Stone for 99% of SNe, GRBs and MSPs, including all recent nearby SNe except SN 1986J, and the more distant SN 2006gy. There is no need to invent exotica, such as "collapsars," to account for GRBs.

This is quite interesting paper written 2001


http://arxiv.org/abs/physics/0107027
Induced Gravity in the Short Range

Authors: C.P.Kouropoulos
(Submitted on 13 Jul 2001 (v1), last revised 9 Aug 2001 (this version, v2))

Abstract: We consider a pair of harmonic oscillators in two or three dimensions of space coupled by the standard electrodynamic forces : the Coulomb, the Lorentz and the electrokinetic forces. The addition of the Lorentz force is mainly felt in the short range and suppresses the radial correlated oscillating mode of such coupled oscillators. This imposes constraints on the system that make the two transverse modes degenerate. As a result, an 1/r antigravitational interaction now appears in the surviving anticorrelated radial zero-mode, which does not allow coherent states to form. As gravitation can only emerge from coherent modes, it can no longer be transitive. Matter in high densities would thus tend to increase its disorder, decouple from its own gravity, from the ordering far infrared Machian background that coheres its rest energy and would become intrinsically unstable. The highly energetic jets from galactic nuclei could be the consequence.

 

[Sundance]

Hello all

This is for Nereid

http://arxiv.org/abs/0812.4813
Angular Energy Distribution of Collapsar-Jets

Authors: Akira Mizuta, Miguel A. Aloy
(Submitted on 28 Dec 2008)

Abstract: Collapsars are fast-spinning, massive stars, whose core collapse liberates an energy, that can be channeled in the form of ultrarelativistic jets. These jets transport the energy from the collapsed core to large distances, where it is dissipated in the form of long-duration gamma-ray bursts. In this paper we study the dynamics of ultrarelativistic jets produced in collapsars. Also we extrapolate our results to infer the angular energy distribution of the produced outflows in the afterglow phase. Our main focus is to look for global energetical properties which can be imprinted by the different structure of different progenitor stars. Thus, we employ a number of pre-supernova, stellar models (with distinct masses and metallicities), and inject in all of them jets with fixed initial conditions. We assume that at the injection nozzle, the jet is mildly relativistic (Lorentz factor $\sim 5$), has a finite half-opening angle ($5^\circ$), and carries a power of $10^{51} $erg s$^{-1}$. These jets arrive intact to the stellar surface and break out of it. A large Lorentz factor region $\Gamma\simmore 100$ develops well before the jet reaches the surface of the star, in the unshocked part of the beam, located between the injection nozzle and the first recollimation shock. These high values of $\Gamma$ are possible because the finite opening angle of the jet allows for free expansion towards the radial direction. We find a strong correlation between the angular energy distribution of the jet, after its eruption from the progenitor surface, and the mass of the progenitors. The angular energy distribution of the jets from light progenitor models is steeper than that of the jets injected in more massive progenitor stars. This trend is also imprinted in the angular distribution of isotropic equivalent energy.

What makes people think that the universe had a start?

A start from what?

If there is an expansion in the universe, than why do the images show a clustering nature, such as Star cluster, galaxy unit, cluster of galaxies, super cluster of clusters of galaxies and so it goes on.


Normal matter makes up about 4% and the rest can be called Plasma or degenerate matter that is found in compact objects such as Stars, Neutron stars excotic stars such as Quark and Neutrino and the so called black holes, stellar black holes and super massive ultra compact matter.

 

[Sundance]

Hello Nereid

It seems you read different papers than me on astropysics.

Maybe you can refer me to the properties of jets from your reading and the different types of jets that are formed from various locations.

and maybe what actually triggers the jets, and how the main jet keeps a stable position for millins of years.

The main trigger for jets is a via a magnetic entanglement and when this happens degenerate matter is formed.
Are you familiar with the process.

 

[Jonathan Scott]

Hello Nereid

It seems you read different papers than me on astropysics.

Maybe you can refer me to the properties of jets from your reading and the different types of jets that are formed from various locations.

and maybe what actually triggers the jets, and how the main jet keeps a stable position for millins of years.

The main trigger for jets is a via a magnetic entanglement and when this happens degenerate matter is formed.
Are you familiar with the process.

You had better define what you mean by "degenerate matter" because it doesn't seem to match the usage which I've previously encountered.

As far as I know, "degenerate matter" is conventionally used for various forms of non-atomic matter which normally only exists at abnormally high pressures, such as in neutron stars.

However, if you simply mean that the matter which forms jets is presumably charged and very energetic and is therefore mostly totally ionized, consisting mainly of free protons and electrons which can subsequently recombine to form neutral hydrogen, then that would be quite plausible to me.

 

[heldervelez]

I have a problem understanding the timings associated to GRBs.

http://en.wikipedia.org/wiki/Gamma-ray_burst"
we know that hey can last for a "...typically a few seconds, but can range from a few milliseconds to several minutes, ..."
and http://en.wikipedia.org/wiki/GRB_080319B"
"The GRB's redshift was measured to be 0.937[5], which means that the explosion occurred about 7.5 billion (7.5×109) years ago...
The emission in both curves then peaks at around 60 seconds before a long exponential decay..."

It seems an extremelly short time for an event at the scale of the dimensions of a star and even worst for a galaxy.
At such a distance, given the space expansion, what should be the period of time of the event at the moment of the occurrence, equivalent to actual the observed 60s ?

 

[Jonathan Scott]

I have a problem understanding the timings associated to GRBs.

http://en.wikipedia.org/wiki/Gamma-ray_burst"
we know that hey can last for a "...typically a few seconds, but can range from a few milliseconds to several minutes, ..."
and http://en.wikipedia.org/wiki/GRB_080319B"
"The GRB's redshift was measured to be 0.937[5], which means that the explosion occurred about 7.5 billion (7.5×109) years ago...
The emission in both curves then peaks at around 60 seconds before a long exponential decay..."

It seems an extremelly short time for an event at the scale of the dimensions of a star and even worst for a galaxy.
At such a distance, given the space expansion, what should be the period of time of the event at the moment of the occurrence, equivalent to actual the observed 60s ?

If something is happening at redshift z, we see it happening (1+z) times slower than it actually happens locally. In this case, 60s observed with a redshift 0.937 means 60s/1.937 locally, about 31s.

 

[Sundance]

Hello All

Johnathan Scott said

As far as I know, "degenerate matter" is conventionally used for various forms of non-atomic matter which normally only exists at abnormally high pressures, such as in neutron stars.

This state of matter is normal, and your right it exists as a neutron matrix where the Neutron are kept apart by Neutron repulsion, the next phase of compaction is Neutron merger, next is quark composites, than Neutrino matter and so on.


Maybe this link may be of help

http://arxiv.org/find/all/1/all:+AND+Higgs+boson/0/1/0/all/0/1?skip=0&query_id=9165ae5fc6ef54b2

http://arxiv.org/find/all/1/all:+AND+2008+AND+Neutron+matter/0/1/0/all/0/1

http://arxiv.org/find/all/1/all:+AND+matter+AND+compact+AND+Quantum+mechanics/0/1/0/all/0/1

The only way to understand and to get away from the chinese whisper is to read scientific papers that are not based on hear say and opinions based on ad hoc ideas.

We see matter on Earth and call it normal, in actual fact this type of matter makes up about 4% of the universe.

 

[granpa]

You had better define what you mean by "degenerate matter" because it doesn't seem to match the usage which I've previously encountered.

As far as I know, "degenerate matter" is conventionally used for various forms of non-atomic matter which normally only exists at abnormally high pressures, such as in neutron stars.
.

non-atomic? what about white dwarfs?

 

[Sundance]

Hello Granpa

White dwarfs do have degenerate matter within the core..

 

[granpa]

and its atomic.

 

[George Jones]

Maybe this link may be of help

http://arxiv.org/find/all/1/all:+AND+Higgs+boson/0/1/0/all/0/1?skip=0&query_id=9165ae5fc6ef54b2

http://arxiv.org/find/all/1/all:+AND+2008+AND+Neutron+matter/0/1/0/all/0/1

http://arxiv.org/find/all/1/all:+AND+matter+AND+compact+AND+Quantum+mechanics/0/1/0/all/0/1

The only way to understand and to get away from the chinese whisper is to read scientific papers that are not based on hear say and opinions based on ad hoc ideas.

Sundance, you have given references to over 1000 papers! Have you read in detail any of them?

Any further posts that use such a blind, shotgun approach will be treated as spam.

 

[Sundance]

Hello George

Mate, I have read a few hundred in detail. It is my reading for the next two years plus a bit more.

The link was made to show the scope of the field.

The people who are interested in reading will find it very interesting.


What is the problem?


Hello Granpa

What do you mean by atomic?