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Overdensity of Discrete X-ray Sources in Outer Galactic Halos
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Robert L. Oldershaw
Nov 5, 2012, 8:36:47 AM11/5/12
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Title: LMXB populations in galaxy outskirts: globular clusters and supernova kicks
Authors: Zhang et al
http://arxiv.org/abs/1211.0399
Arxiv.org Nov 5th listing
"For the first time, we systematically explored the population of discrete X-ray sources in the outskirt of early-type galaxies. Based on...20 galaxies observed with Chandra we revealed an overdensity of X-ray sources in their outskirts. They appear as halos of resolved sources around galaxies, distributing much broader than the stellar light, and extended out to at least [10 times the effective radius]. These halos are composed of sources fainter than ~ 5 x 10^38 erg/s, whereas more luminous sources appea
r to follow the distribution of stellar light, ..."
This study could not see sources fainter than ~ 10^37 erg/s, but the distribution and properties of the bright component of the discrete X-ray population in the DM halo is quite interesting.
I am less enthusiastic about the authors speculative interpretations of the data.
If the limiting X-ray luminosity could be somehow lowered to the 10^26 erg/s to 10^31 erg/s range, then we might see the light, so to speak, not to mention the blackness of the dark.
Robert L. Oldershaw
Discrete Scale Relativity
http://www3.amherst.edu/~rloldershaw
Authors: Zhang et al
http://arxiv.org/abs/1211.0399
Arxiv.org Nov 5th listing
"For the first time, we systematically explored the population of discrete X-ray sources in the outskirt of early-type galaxies. Based on...20 galaxies observed with Chandra we revealed an overdensity of X-ray sources in their outskirts. They appear as halos of resolved sources around galaxies, distributing much broader than the stellar light, and extended out to at least [10 times the effective radius]. These halos are composed of sources fainter than ~ 5 x 10^38 erg/s, whereas more luminous sources appea
r to follow the distribution of stellar light, ..."
This study could not see sources fainter than ~ 10^37 erg/s, but the distribution and properties of the bright component of the discrete X-ray population in the DM halo is quite interesting.
I am less enthusiastic about the authors speculative interpretations of the data.
If the limiting X-ray luminosity could be somehow lowered to the 10^26 erg/s to 10^31 erg/s range, then we might see the light, so to speak, not to mention the blackness of the dark.
Robert L. Oldershaw
Discrete Scale Relativity
http://www3.amherst.edu/~rloldershaw
Robert L. Oldershaw
Nov 16, 2012, 3:13:38 AM11/16/12
to
On Monday, November 5, 2012 8:37:08 AM UTC-5, Robert L. Oldershaw wrote:
Here is a new paper from today's arXiv.org posting.
http://arxiv.org/abs/1211.3372
The authors argue that their research suggests that "at least some old [globular clusters of the Milky Way galaxy] could have hundreds of stellar-mass black holes at present. Since nearly all of our BHs are single, our prediction is consistent with the small number of BH XRBs detected in clusters to date."
Given that there are ~300 GCs in the MWG, this new research points to a substantial population of isolated stellar-mass black holes that had not been identified before. A relatively "small" population, but the actual numbers are as yet unknown and I like the trend.
Robert L. Oldershaw
�The most beautiful thing we can experience is the mysterious. It is the source of all true art and all science. He to whom this emotion is a stranger, who can no longer pause to wonder and stand rapt in awe, is as good as dead: his eyes are closed.� - A. Einstein
Here is a new paper from today's arXiv.org posting.
http://arxiv.org/abs/1211.3372
The authors argue that their research suggests that "at least some old [globular clusters of the Milky Way galaxy] could have hundreds of stellar-mass black holes at present. Since nearly all of our BHs are single, our prediction is consistent with the small number of BH XRBs detected in clusters to date."
Given that there are ~300 GCs in the MWG, this new research points to a substantial population of isolated stellar-mass black holes that had not been identified before. A relatively "small" population, but the actual numbers are as yet unknown and I like the trend.
Robert L. Oldershaw
�The most beautiful thing we can experience is the mysterious. It is the source of all true art and all science. He to whom this emotion is a stranger, who can no longer pause to wonder and stand rapt in awe, is as good as dead: his eyes are closed.� - A. Einstein
Phillip Helbig---undress to reply
Nov 16, 2012, 4:29:12 PM11/16/12
to
In article <mt2.0-29837...@hydra.herts.ac.uk>, "Robert L.
Let's say 500. So, 500*300/2 = 7500. 7500 among a population of at
least 100 billion stars is a substantial population? Stellar-mass black
holes are a known end-product of stellar evolution, so no surprise here.
Oldershaw" <rlold...@amherst.edu> writes:
> The authors argue that their research suggests that "at least some old
> [globular clusters of the Milky Way galaxy] could have hundreds of
> stellar-mass black holes at present. Since nearly all of our BHs are
> single, our prediction is consistent with the small number of BH XRBs
> detected in clusters to date."
>
> Given that there are ~300 GCs in the MWG, this new research points to a
> substantial population of isolated stellar-mass black holes that had not
> been identified before. A relatively "small" population, but the actual
> numbers are as yet unknown and I like the trend.
At least some, so not all. Let's be generous and say half. Hundreds?
> The authors argue that their research suggests that "at least some old
> [globular clusters of the Milky Way galaxy] could have hundreds of
> stellar-mass black holes at present. Since nearly all of our BHs are
> single, our prediction is consistent with the small number of BH XRBs
> detected in clusters to date."
>
> Given that there are ~300 GCs in the MWG, this new research points to a
> substantial population of isolated stellar-mass black holes that had not
> been identified before. A relatively "small" population, but the actual
> numbers are as yet unknown and I like the trend.
Let's say 500. So, 500*300/2 = 7500. 7500 among a population of at
least 100 billion stars is a substantial population? Stellar-mass black
holes are a known end-product of stellar evolution, so no surprise here.
Eric Gisse
Nov 16, 2012, 4:49:37 PM11/16/12
to
On Friday, November 16, 2012 2:13:59 AM UTC-6, Robert L. Oldershaw wrote:
[...]
The literature is extremely clear on this, regardless of how much straw grasping you do.
If you disagree, feel free to produce a sample calculation of what fraction of dark matter could be accounted for using your latest guess.
[Mod. note: let's say a hundred stellar mass BHs in each of the 300
GCs; so that's 30,000 stellar-mass BHs. So, in accounting for the dark
matter, that's, roughly, 30,000 solar masses down, 999,999,970,000 to
go... -- mjh]
[...]
>
> Given that there are ~300 GCs in the MWG, this new research points to a substantial population of isolated stellar-mass black holes that had not been identified before. A relatively "small" population, but the actual numbers are as yet unknown and I like the trend.
Sorry Robert, microlensing observations are pretty clear about what the bulk of the dark matter population isn't. Which is to say "it isn't black holes".
> Given that there are ~300 GCs in the MWG, this new research points to a substantial population of isolated stellar-mass black holes that had not been identified before. A relatively "small" population, but the actual numbers are as yet unknown and I like the trend.
The literature is extremely clear on this, regardless of how much straw grasping you do.
If you disagree, feel free to produce a sample calculation of what fraction of dark matter could be accounted for using your latest guess.
[Mod. note: let's say a hundred stellar mass BHs in each of the 300
GCs; so that's 30,000 stellar-mass BHs. So, in accounting for the dark
matter, that's, roughly, 30,000 solar masses down, 999,999,970,000 to
go... -- mjh]
Robert L. Oldershaw
Nov 17, 2012, 2:58:57 PM11/17/12
to
On Friday, November 16, 2012 4:49:58 PM UTC-5, Eric Gisse wrote:
>
> Sorry Robert
---------------------------------------------
The journey of 1,000 miles begins with a single step.
I predict that at least a trillion stellar-mass black holes will be discovered in our galaxy, to go along with the at least a trillion planetary-mass objects discovered by Sumi et al.
Why have microlensing teams discovered the planetary-mass population, but have yet to see no more than a tiny fraction of the stellar-mass population? I cannot answer that. I can only assume that some systematic error in the assumptions regarding the velocity distribution, or the spatial distributions, or some unknown unknown have led to incorrect conclusions.
[Mod. note: presumably you also acknowledge the possibility that you
might be wrong? -- mjh]
--
I am well aware that I am way out on a limb on this issue, but it is DSR's most definitive prediction and I expect to be fully vindicated. Like I say, the trends seem propitious, so I think I will calmly wait another decade or so.
Robert L. Oldershaw
Discrete Scale Relativity
“The next great awakening of the human intellect may well produce a method of understanding the qualitative content of the equations.” - Richard Feynman
>
> Sorry Robert
---------------------------------------------
> [Mod. note: let's say a hundred stellar mass BHs in each of the 300
> GCs; so that's 30,000 stellar-mass BHs. So, in accounting for the dark
> matter, that's, roughly, 30,000 solar masses down, 999,999,970,000 to
> go... -- mjh]
------------------------------------------------------
> GCs; so that's 30,000 stellar-mass BHs. So, in accounting for the dark
> matter, that's, roughly, 30,000 solar masses down, 999,999,970,000 to
> go... -- mjh]
The journey of 1,000 miles begins with a single step.
I predict that at least a trillion stellar-mass black holes will be discovered in our galaxy, to go along with the at least a trillion planetary-mass objects discovered by Sumi et al.
Why have microlensing teams discovered the planetary-mass population, but have yet to see no more than a tiny fraction of the stellar-mass population? I cannot answer that. I can only assume that some systematic error in the assumptions regarding the velocity distribution, or the spatial distributions, or some unknown unknown have led to incorrect conclusions.
[Mod. note: presumably you also acknowledge the possibility that you
might be wrong? -- mjh]
--
I am well aware that I am way out on a limb on this issue, but it is DSR's most definitive prediction and I expect to be fully vindicated. Like I say, the trends seem propitious, so I think I will calmly wait another decade or so.
Robert L. Oldershaw
Discrete Scale Relativity
Phillip Helbig---undress to reply
Nov 17, 2012, 3:04:31 PM11/17/12
to
In article <mt2.0-4416...@hydra.herts.ac.uk>, Phillip
Helbig---undress to reply <hel...@astro.multiCLOTHESvax.de> writes:
> At least some, so not all. Let's be generous and say half. Hundreds?
> Let's say 500. So, 500*300/2 = 7500. 7500 among a population of at
> least 100 billion stars is a substantial population? Stellar-mass black
> holes are a known end-product of stellar evolution, so no surprise here.
Sorry, should be 75,000. Still not substantial.
> At least some, so not all. Let's be generous and say half. Hundreds?
> Let's say 500. So, 500*300/2 = 7500. 7500 among a population of at
> least 100 billion stars is a substantial population? Stellar-mass black
> holes are a known end-product of stellar evolution, so no surprise here.
Eric Gisse
Nov 18, 2012, 5:19:12 AM11/18/12
to
On Saturday, November 17, 2012 1:59:20 PM UTC-6, Robert L. Oldershaw wrote:
> On Friday, November 16, 2012 4:49:58 PM UTC-5, Eric Gisse wrote:
>
> >
>
> > Sorry Robert
>
> ---------------------------------------------
>
> > [Mod. note: let's say a hundred stellar mass BHs in each of the 300
>
> > GCs; so that's 30,000 stellar-mass BHs. So, in accounting for the dark
>
> > matter, that's, roughly, 30,000 solar masses down, 999,999,970,000 to
>
> > go... -- mjh]
>
> ------------------------------------------------------
>
>
>
> The journey of 1,000 miles begins with a single step.
>
>
>
> I predict that at least a trillion stellar-mass black holes will be discovered in our galaxy, to go along with the at least a trillion planetary-mass objects discovered by Sumi et al.
Too bad the possibility has been conclusively excluded, especially because it would have been discovered far earlier than the planetary-mass objects.
> On Friday, November 16, 2012 4:49:58 PM UTC-5, Eric Gisse wrote:
>
> >
>
> > Sorry Robert
>
> ---------------------------------------------
>
> > [Mod. note: let's say a hundred stellar mass BHs in each of the 300
>
> > GCs; so that's 30,000 stellar-mass BHs. So, in accounting for the dark
>
> > matter, that's, roughly, 30,000 solar masses down, 999,999,970,000 to
>
> > go... -- mjh]
>
> ------------------------------------------------------
>
>
>
> The journey of 1,000 miles begins with a single step.
>
>
>
> I predict that at least a trillion stellar-mass black holes will be discovered in our galaxy, to go along with the at least a trillion planetary-mass objects discovered by Sumi et al.
>
>
>
> Why have microlensing teams discovered the planetary-mass population, but have yet to see no more than a tiny fraction of the stellar-mass population? I cannot answer that. I can only assume that some systematic error in the assumptions regarding the velocity distribution, or the spatial distributions, or some unknown unknown have led to incorrect conclusions.
The deflection of light via a gravitational lens is directly proportional to its' mass. The fact that low mass lensing objects are discovered while objects that are a factor of ten thousand larger are NOT detected doesn't seem to concern you at all.
I love the notion that it has to be some sort of "systematic error". Do you even know what that means? There have been something like a half dozen *different* microlensing collaborations over the years that have searched for ultracompacts.
Spatial distribution? They search the entire LMC plus a good chunk of its' halo. I've given you the references that show the grids they use. You arguing that it is a "spatial distribution" issue indicates you don't have much of an idea.
Velocity distribution? You've never been able to quantitatively explain what you mean, or show a viable model that accounts for your claims.
You are wrong, and this is as much of an admission as we are ever going to get.
Can you finally move on now?
Phillip Helbig---undress to reply
Nov 18, 2012, 5:26:42 AM11/18/12
to
In article <mt2.0-23195...@hydra.herts.ac.uk>, "Robert L.
trillion have been discovered at any one time, you can always say "they
haven't been discovered yet". Note that DSR has made definitive (your
words), testable, falsifiable predictions, e.g. electron substructure.
These have been falsified. By definition, a theory has been falsified
if a definitive prediction has been falsified.
If you have some sort of revised version of DSR which is essentially the
same but predicts no electron substructure, or on a scale not yet
accessible (as the original prediction predicted structure on a scale
not accessible then), then you are moving the goalposts, something you
have repeatedly criticized in other theories.
Oldershaw" <rlold...@amherst.edu> writes:
> I predict that at least a trillion stellar-mass black holes will be
> discovered in our galaxy, to go along with the at least a trillion
> planetary-mass objects discovered by Sumi et al.
Note that this is not a falsifiable prediction, i.e. if less than a
> I predict that at least a trillion stellar-mass black holes will be
> discovered in our galaxy, to go along with the at least a trillion
> planetary-mass objects discovered by Sumi et al.
trillion have been discovered at any one time, you can always say "they
haven't been discovered yet". Note that DSR has made definitive (your
words), testable, falsifiable predictions, e.g. electron substructure.
These have been falsified. By definition, a theory has been falsified
if a definitive prediction has been falsified.
If you have some sort of revised version of DSR which is essentially the
same but predicts no electron substructure, or on a scale not yet
accessible (as the original prediction predicted structure on a scale
not accessible then), then you are moving the goalposts, something you
have repeatedly criticized in other theories.
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