Questions tagged [relativistic-jets]
To be used for astrophysical jets -- collimated, relativistic outflows often due to accretion onto compact objects.
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Why is there no jet visible in the M87* black hole radio image?
M87 is known to contain a jet that is likely created by the supermassive black hole at its center. The recently published radio image taken by the Event Horizon Telescope does not display any ...
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Can star such as our sun produce astrophysical jet?
Must there be an accretion disc for astrophysical jet to form? Does it have anything to do with how massive the star is? Since it is already a hot plasma and produce it's own magnetic field, can't it ...
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2answers
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How can cosmic jets exist? [duplicate]
Cosmic jets are jets of matter ejected from super massive black holes.
The gravitational pull of a black hole is so high that even light can't escape it.
Yet particles with mass traveling at speeds ...
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0answers
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What is the $\eta$-reflection method to estimate the background by CMS?
When I used the "Fastjet Package" to reconstruct jet and calculate the jet-shape, I need to estimate the background. I saw from paper:
"The η-reflection method as the CMS experiment did, i.e., ...
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1answer
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Why the reconstructed jet need to substract the “background”?
There is a trouble bother me a long time. I know it may be stupid
question. But I really need your help. It's in the CMS paper:
CMS Collaboration, CMS Physics Analysis Summary No. CMS-PAS-HIN-12-013,...
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0answers
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What Black Holes causes Astrophysical Jets?
this is my first question, so here goes, I was wondering, what kind of Black Holes creates Astrophysical Jets that shows as massive clouds of particles shooting out of the Black Hole. What would be ...
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0answers
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Can rotating black hole have toroidal event horizon with penetrating relativistic jet(s)?
It is conjectured that a rotating black hole has at its center a ring-shaped singularity.
Thus, at the center of the ring-shaped singularity the gravitational field must be zero (similar to ...
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1answer
125 views
Relativistic emission from a spherical outflow (doppler boost and apparent velocities)
If I'm observing radiation emitted from a spherical outflow, is it correct to assume that that on the axis of the spherical outflow perpendicular to the observer the doppler boost is similar to the ...
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2answers
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Is it possible that black holes have an anti-matter jet? [closed]
If we can think of the black hole in the center of our galaxy as a group of decaying atoms with neutrinos coming from one side in the jet and anti neutrinos from the other side then would it be ...
4
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2answers
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How do we know that Quasars actually produce collimated jets?
How did astrophysicists know this? Of course it's very difficult to directly see the jets from Quasars, so I'm wondering how did they come to the conclusion that Quasars produce collimated jets or ...
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1answer
57 views
The production of cosmic jets [duplicate]
For cosmic jets produced in gamma ray bursts or quasars, I've read that you have to assume a "Force-free magnetosphere" in order to explain these phenomena through electromagnetism. From my ...
2
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1answer
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Do AGN produce protons that are relativistic enough to collide with the CMB and make pions?
AGN (Active Galactic Nuclei) produce protons in their jets and they are relativistic. I was reading about photo-pion production, where a proton and photon annihilate to produce a pion. Could this ...
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Can objects exit a black hole?
I read an article claiming that an object had been observed to be ejected from a black hole.
This was the newest article I could find published on it but they still seem uncertain what the object was ...
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3answers
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Why are pulsar's radiation beams collimated?
Every picture of a pulsar I see shows a very collimated radiation beam. What is the mechanism generating such a collimation?
Note: I am not talking about "relativistic jets". I am talking about ...
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0answers
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Lense-Thirring Precession of short GRBs
Stone et al. 2014 have proposed that the jet resulting from the merger of a black hole (BH) and neutron star (NS) may precess due to Lense Thirring torques
A large rotating mass e.g. the Earth, can ...
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1answer
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Relativistic blast waves in medium of non uniform density
The relativistic outflow of a gamma ray burst drives a shock into the circumburst medium. This medium could have a uniform density $n_0$ or a density profile of the form, $n(r) \propto r^{-2}$.
For ...
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1answer
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Question about the Blandford–Znajek process
I've been trying to understand the Blandford–Znajek process which explains how Gamma Ray Bursts form, but it's still not clear to me how it works. In this article, several theories about the formation ...
5
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3answers
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Why are the jets of the “light saber” star slightly curved?
Why don't the jets of the HH-24 object follow a straight line?
In the image below, notice how they bend towards left from the expected straight line.
Is it an optical distortion, or some nearby ...
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1answer
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Black hole corona and bipolar outflows
What are black hole coronas? Are they different from accretion disks? If so, how are they formed?
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Origin of Jet production: Active Galactic Nuclei
According to Netzer's book on Active Galactic Nuclei (AGN), pair production ($\gamma \gamma \leftrightarrow e^+ e^-$) which causes AGN jets presumably happens in "the corona of the central accretion ...
3
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1answer
338 views
How do black hole jets form? [duplicate]
A black hole, neutron star or any object that has accumulated an accretion disc, sometimes features opposing jets, positioned perpendicular to the accretion disc.
I understand that these jets are ...
21
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2answers
8k views
How can Quasars emit anything if they're black holes?
We've heard it many times, nothing can escape the gravity of a black hole, even light once it's past the event horizon. If this is true, how can a black hole emit anything? Quasars are massive black ...
2
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1answer
188 views
Easy formula for ultrarelativistic bremsstrahlung?
I am very curious if an easy calculable formula for the bremstrahlung radiation of deeply relativistic, charged particles exists, if they are moving on circular orbit:
$P(E,m_0,Q,r)=?$
...where
$P$ ...
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1answer
205 views
(Polar jets) Is it possible that black holes radiate substantial amount of the mass/energy they accrete?
Is the amount of energy a black hole emit through polar jets comparable to the mass it accretes or is it negligible? Here I am mostly concerned about the observational findings as opposed to the ...
9
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2answers
387 views
Which way do black hole jets spin?
The centers of black holes and quasars often have jets coming out the two poles of an accretion disk, say north and south. Is it known if the two jets spin in the same direction or opposite ...
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1answer
573 views
Visual representations of black holes
Some black holes emit jets that are rapidly circling the poles of what appears to be a sphere at the center of the black hole, cf. Fig. 1.
Is there really a sphere here and how far (relative to the ...
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1answer
460 views
Why are polar jets emitted along the axis of rotation?
Why are streams of energy-matter emitted along the axis of rotation of compact objects?
(or) what is the reason that they are emitted along the axis of rotation of a compact object?
8
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1answer
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What is the proper time used in relativistic non-equilibrium statistical physics?
In the literature one often finds covariant relativistic generalizations of classical non equilibrium statistical equations (Boltzmann, Vlasov, Landau, Fokker-Planck, etc...) but I wonder what is the ...
4
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1answer
400 views
models for astrophysical relativistic jets from compact objects
what is the simplest way to understand the physics of relativistic jets? we know that they have axial symmetry with very tight angular spread, presumably aligned with the axis of rotation of the ...
3
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1answer
247 views
Pulsar beam radiant intensity distribution
I'm curious about the radiant intensity distribution of pulsars: what's the general dependence of intensity on angle, and what are typical angular beam widths? How much does the beam width vary ...
8
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1answer
251 views
Where do the bipolar jets of black holes come from?
How are they formed? And why are they so bright?
