<p>Theoretically, Yes. Relativistic jets accelerate beams of plasma, so  due ionization it has a lack of baryonic matter as @Uhoh pointed, instead it contains a lot of leptons and antileptons like positrons. But there is a possible scenario covered in <a href="https://ui.adsabs.harvard.edu/abs/2013Natur.504..260D/abstract" rel="nofollow noreferrer">research papers</a> that maybe baryons arising from the accretion disk could be injected into the jet which so as appears in X-ray binary, 4U1630-47. I agree the paper might no be so assuring but there is a well enough chance of baryonic matter in a jet. Even if it is not there minute interactions with the interstellar medium and surrounding could in theory inject baryons into the jet. As to how the relativistic jet could cool traveling  at 2/3rd the speed of light through inverse square law eventually it would disperse in the surrounding and cool to form dust particles, it could also cool through <strong>inverse compton cooling</strong>.</p>
<p>As for could we detect flashes of radiation when dust speaks smash into meteoroids at relativistic speeds?, Yeah the impact flash, could create tiny peaks of radiation but it would be very hard to detect such radiation because it wouldn't be intense enough to travel to Earth considering inverse square law.</p>

CC BY-SA 4.0
2024-05-07T17:43:27.400Z
I am also concerned that the gas would expand so much (do to it's very high initial temperature) that it gets too sparse before the stuff inside can condense.

But this is the best answer "we don't really know" because there are limits to our models.
Kevin Kostlan
CC BY-SA 4.0
2024-05-08T06:59:45.273Z
@KevinKostlan To be honest, that's a really interesting theory!. So according to me, I think it might depend on the cooling factors, how straightline the jet is, how much velocity the jet is, and of course the temperature. So you might be right, we really don't know what is the reality, But my point is, that although the chances are low. By sufficient cooling in a short amount of time, thereotically it might be possible
Arjun
CC BY-SA 4.0
2024-05-08T07:02:00.467Z
@KevinKostlan Quoting "Interactions with cold molecular clouds might do gas condensation as a result of compression". So it also might depend on the medium it travels through
Arjun
CC BY-SA 4.0
2024-05-09T02:29:39.903Z
Interesting, I would think that interactions would generate so much heat that it would fight against cooling?
Kevin Kostlan
CC BY-SA 4.0
2024-05-09T06:57:28.843Z
@KevinKostlan Yes, the heat would rather go down gradually, from the heat generated from the collisions. As the laws of thermodynamic states that the heat flowing from hotter to colder regions transfer heat of their own until thermal equilibrium is reached. So if the matter is dense enough it would just be a matter of time before it reaches thermal equilibrium and proceeds to cool further.
Arjun
CC BY-SA 4.0
2024-05-02T03:51:23.253Z
2024-05-02T10:30:33.230Z
2024-05-02T10:30:33.230Z
Arjun
<p>Black-holes accreting matter can emit <a href="https://www.nustar.caltech.edu/page/relativistic_jets" rel="nofollow noreferrer">jets of plasma</a> that can exceed half the speed of light.</p>
<p>Can these jets cool off enough that dust particles condense in them? If so, could we detect flashes of radiation when dust specks smash into meteoroids at relativistic speeds?</p>

CC BY-SA 4.0
2024-04-24T04:32:51.333Z
Is a simpler question if it contains any baryonic matter at all? I'd assumed it was just electrons and some positrons, since protons are ~2000 times heavier and therefore wouldn't be accelerated so much. But it seems I have no idea.
uhoh
CC BY-SA 4.0
2024-04-24T06:41:27.310Z
Some info on jet material: https://physics.stackexchange.com/a/522613/123208
PM 2Ring
CC BY-SA 4.0
2024-04-25T00:29:40.610Z
What about plasma and relativistic speeds makes you think anything in there can cool off and condense?
Mithoron
CC BY-SA 4.0
2024-04-25T04:05:24.757Z
@Mithoron: https://en.wikipedia.org/wiki/Dusty_plasma
It has millions of years to cool off via radiation (thousands of years for micro-quasars in our galaxy).
Kevin Kostlan
CC BY-SA 4.0
2024-04-25T12:21:23.513Z
If the jet cools off then it would not be observable.  So how would we know?
eshaya
<black-hole>
Does a relativistic jet contain dust particles?
Kevin Kostlan
# Does a relativistic jet contain dust particles?

(Asked by: username_0 on 2024-04-24)

Black-holes accreting matter can emit [jets of plasma](https://www.nustar.caltech.edu/page/relativistic_jets) that can exceed half the speed of light.

Can these jets cool off enough that dust particles condense in them? If so, could we detect flashes of radiation when dust specks smash into meteoroids at relativistic speeds?

**Tags:** black-hole

> **Comments:**
> **username_1**: Is a simpler question if it contains any baryonic matter at all? I'd assumed it was just electrons and some positrons, since protons are ~2000 times heavier and therefore wouldn't be accelerated so much. But it seems I have no idea.  
> **username_2**: Some info on jet material: https://physics.stackexchange.com/a/522613/123208  
> **username_3**: What about plasma and relativistic speeds makes you think anything in there can cool off and condense?  
> **username_0**: @username_3: https://en.wikipedia.org/wiki/Dusty_plasma It has millions of years to cool off via radiation (thousands of years for micro-quasars in our galaxy).  
> **username_4**: If the jet cools off then it would not be observable.  So how would we know?  

---

## 1 answers

### Answer by username_5 on 2024-05-02. Score: 2 | Accepted answer

Theoretically, Yes. Relativistic jets accelerate beams of plasma, so due ionization it has a lack of baryonic matter as @username_1 pointed, instead it contains a lot of leptons and antileptons like positrons. But there is a possible scenario covered in [research papers](https://ui.adsabs.harvard.edu/abs/2013Natur.504..260D/abstract) that maybe baryons arising from the accretion disk could be injected into the jet which so as appears in X-ray binary, 4U1630-47. I agree the paper might no be so assuring but there is a well enough chance of baryonic matter in a jet. Even if it is not there minute interactions with the interstellar medium and surrounding could in theory inject baryons into the jet. As to how the relativistic jet could cool traveling at 2/3rd the speed of light through inverse square law eventually it would disperse in the surrounding and cool to form dust particles, it could also cool through **inverse compton cooling**.

As for could we detect flashes of radiation when dust speaks smash into meteoroids at relativistic speeds?, Yeah the impact flash, could create tiny peaks of radiation but it would be very hard to detect such radiation because it wouldn't be intense enough to travel to Earth considering inverse square law.

> **Comments:**
> **username_0**: I am also concerned that the gas would expand so much (do to it's very high initial temperature) that it gets too sparse before the stuff inside can condense.  But this is the best answer "we don't really know" because there are limits to our models.  
> **username_5**: @username_0 To be honest, that's a really interesting theory!. So according to me, I think it might depend on the cooling factors, how straightline the jet is, how much velocity the jet is, and of course the temperature. So you might be right, we really don't know what is the reality, But my point is, that although the chances are low. By sufficient cooling in a short amount of time, thereotically it might be possible  
> **username_5**: @username_0 Quoting "Interactions with cold molecular clouds might do gas condensation as a result of compression". So it also might depend on the medium it travels through  
> **username_0**: Interesting, I would think that interactions would generate so much heat that it would fight against cooling?  
> **username_5**: @username_0 Yes, the heat would rather go down gradually, from the heat generated from the collisions. As the laws of thermodynamic states that the heat flowing from hotter to colder regions transfer heat of their own until thermal equilibrium is reached. So if the matter is dense enough it would just be a matter of time before it reaches thermal equilibrium and proceeds to cool further.  

---

