WIMPs AWOL Yet Again

One hopes Dan Hooper will turn down the hype now.

http://journals.aps.org/prl/abstract...ett.116.051102

[[Mod. note -- The preprint version of this appears to be
http://arxiv.org/abs/1506.05104
-- jt]]

Gamma-ray excess in MWG central region is NOT due to WIMPs, or any
other form of ad hoc hypothetical particle dark matter.

Rather it is due to stellar-mass astrophysical sources at the 10
sigma level. The sources remain to be fully identified, but
millisecond pulsars are considered to be the most likely candidates.
Might they actually be a completely unexpected population of
stellar-mass black holes? We shall see!

RLO
http://www3.amherst.edu/~rloldershaw
"Those who expect the old ideas to last forever are doomed to live
confined within them"

In article ,
"Robert L. Oldershaw" writes:

Gamma-ray excess in MWG central region is NOT due to WIMPs, or any
other form of ad hoc hypothetical particle dark matter.

Even assuming that this is true,

Rather it is due to stellar-mass astrophysical sources at the 10
sigma level.

Can you explain this?

The sources remain to be fully identified, but
millisecond pulsars are considered to be the most likely candidates.

OK.

Might they actually be a completely unexpected population of
stellar-mass black holes? We shall see!

Can you explain how stellar-mass black holes could emit the radiation in
question---quantitatively?

I remind posters here that you still cannot explain why this putative
population is not seen in microlensing searches.

On Sunday, February 7, 2016 at 12:44:54 PM UTC-5, Phillip Helbig
(undress to reply) wrote:

=20
I remind posters here that you still cannot explain why this putative=20
population is not seen in microlensing searches.

If the population of objects emitting this radiation turns out to
be on the order of 100,000 millisecond pulsars, as proposed by the
authors of the paper, then microlensing studies should detect them
if they are looking in the right place and microlensing observations
are feasible and effective in this particular setting.

[[Mod. note -- Alas, microlensing observations aren't feasable and
effective in this setting:
* It would be hard to distinguish brightness fluctuations caused by
microlensing from those caused by turbulence in the interstellar
medium.
* Microlensing only happens if the lens is *very* precisely lined up
along the line of sight to the background object. Using the central
bulge of our galaxy (= on the order of 1e10 stars = on the order of
1e10 potential lenses) gives a probability of any given source being
microlensed at any given time is on the order of 1e-7 or so, which
is just detectable by monitoring star fields of 10s to 100s of
millions of background stars. So a population of "only" 1e5
millisecond pulsars is going to produce something on the order of
1e5 times fewer microlensing events, i.e., in practice we probably
wouldn't see any events.
-- jt]]

On Monday, February 8, 2016 at 9:03:15 PM UTC-5, Robert L. Oldershaw wrote:

And here is another negative result in the endless "WIMP" search.

http://arxiv.org/abs/1603.05120

The authors say it confirms the latest LUX and SuperCDMS no-show results.

RLO (yawn) http://www3.amherst.edu/~rloldershaw

On Friday, March 18, 2016 at 4:57:34 AM UTC-4, Robert L. Oldershaw wrote:
On Monday, February 8, 2016 at 9:03:15 PM UTC-5, Robert L. Oldershaw wrote:

And here is another negative result in the endless "WIMP" search.


And here is yet another: http://arxiv.org/abs/1603.08914

This time it from CMS at LHC.

On Thursday, March 31, 2016 at 2:27:52 AM UTC-4, Robert L. Oldershaw wrote:
On Friday, March 18, 2016 at 4:57:34 AM UTC-4, Robert L. Oldershaw wrote:
On Monday, February 8, 2016 at 9:03:15 PM UTC-5, Robert L. Oldershaw wrote:

And here is another negative result in the endless "WIMP" search.


And here is yet another: http://arxiv.org/abs/1603.08914

This time it from CMS at LHC.

Following on the heels of the "WIMP" no-show in the LUX experiment,
we now have yet another "WIMP" no-show at PandaX-II.

http://arxiv.org/abs/1607.07400

RLO
http://www3.amherst.edu/~rloldershaw

In article ,
"Robert L. Oldershaw" writes:

And here is another negative result in the endless "WIMP" search.

And here is yet another: http://arxiv.org/abs/1603.08914

This time it from CMS at LHC.

Following on the heels of the "WIMP" no-show in the LUX experiment,
we now have yet another "WIMP" no-show at PandaX-II.

http://arxiv.org/abs/1607.07400

Why the scare quotes?

One could have said the same things about gravitational waves for
several decades. Would that have prove that they don't exist? No.

On Wednesday, July 27, 2016 at 6:54:01 PM UTC-4, Phillip Helbig (undress to reply) wrote:


Why the scare quotes?

One could have said the same things about gravitational waves for
several decades. Would that have prove that they don't exist? No.

-----------------------------

When a "WIMP" is actually discovered, and not rejected as another
in a long, long line of false-positives, then I will remove the
reality quotes.

RLO
http://www3.amherst.edu/~rloldershaw

On Friday, July 29, 2016 at 12:10:58 AM UTC-4, Robert L. Oldershaw wrote:


When a "WIMP" is actually discovered, and not rejected as another
in a long, long line of false-positives, then I will remove the
reality quotes.


Today (7/28/16) we have a report from the H.E.S.S Collaboration. They
have been observing the center 300 pc of the Galaxy for 10 years looking
for evidence for gamma-rays attributable to "particle dark matter
annihilations".

http://arxiv.org/abs/1607.08142

Results after 10 years of data: no-show.

RLO
http://www3.amherst.edu/~rloldershaw

In article ,
"Robert L. Oldershaw" writes:

When a "WIMP" is actually discovered, and not rejected as another
in a long, long line of false-positives, then I will remove the
reality quotes.

I expect you to put them around "primordial black holes" as well until
these are discovered.

Today (7/28/16) we have a report from the H.E.S.S Collaboration. They
have been observing the center 300 pc of the Galaxy for 10 years looking
for evidence for gamma-rays attributable to "particle dark matter
annihilations".

http://arxiv.org/abs/1607.08142

Results after 10 years of data: no-show.

No problem. If they hadn't looked, they wouldn't have been able to draw
any conclusions. Observations are the basis of science.

Note also that one of the main motivation for the MACHO and similar
collaborations was to find a substantial fraction of the dark matter in
compact objects in our galactic halo. After 25 years of data, no show.

Gravitational waves were a no show for 100 years.