DAMA/Libra claim confirmation of direct dark-matter detection

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Jonathan Thornburg [remove -animal to reply] - 21 Apr 2008 21:44 GMT

A recent newspaper story by Dennis Overbye in the New York Times
http://www.nytimes.com/2008/04/17/science/space/17dark.html
(probably needs signup-for-user-tracking-registration to view)
and elsewhere
http://www.iht.com/articles/2008/04/17/healthscience/dark.php
reports that
A team of Italian and Chinese physicists on Wednesday renewed a
controversial claim that they had detected the mysterious dark
matter particles that astronomers say swaddle the galaxies in halos
and direct the evolution of the universe.

The team, called Dama, from "DArk MAtter," and led by Rita Bernabei
of the University of Rome, has maintained since 2000 that a yearly
modulation in the rate of flashes in a detector nearly a mile
underneath the Gran Sasso mountain in Italy is the result of the
Earth's passage through a "wind" of dark matter particles as it
goes around the Sun. Other groups of hunters of dark matter have
just as consistently failed to find any evidence of the putative
particles.

At a meeting in Venice, Dr. Bernabei reported that a new, bigger
experiment named Dama/Libra had now observed the same modulation.

Can anyone point to a more technical account of the claim? Is there
a preprint out?

Signature

-- Jonathan Thornburg <J.Thornburg@soton.ac.uk>
School of Mathematics, U of Southampton, England
"It is especially difficult to find exact solutions of the equations,
as the equations are nonlinear." -- Einstein, fall 1913, discussing
nonlinear gravitational radiation with Born (quoted in MTW chapter 35)

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Jonathan Thornburg [remove -animal to reply] - 22 Apr 2008 22:39 GMT

I asked if anyone had more technical info on the DAMA/Libra claim of
a direct dark-matter detection. To follow up on my own query :), here
are some pointers I've found in the last day-and-a-half:
* Details of the claim: http://arxiv.org/abs/0804.2741
* Non-technical overview (I think lacking a suitable degree of skepticism)
at Bad Astronomy:
http://www.badastronomy.com/bablog/2008/04/21/dark-matter-detected/
* Criticism by doriga at
http://dorigo.wordpress.com/2008/04/17/about-the-dama-libra-result/
* Strong criticism by Juan Collar at Cosmic Variance:
http://cosmicvariance.com/2008/04/21/guest-post-juan-collar-on-dark-matter-detection/

ciao,

Signature

-- "Jonathan Thornburg [remove -animal to reply]" <J.Thornburg@soton.ac-zebra.uk>
School of Mathematics, U of Southampton, England
"ActiveX as a security component? Isn't that like Ben and Jerry's ice
cream as a diet component?" -- Bill Unruh, sci.crypt, 18.Jul.2003

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pkarwow@googlemail.com - 22 Apr 2008 22:39 GMT

Hello.

I know - there is April now - so it's good time for various, crazy
proposals. Anyway the whole idea does not looks mad enough
for me in order to be considered true. Physics is an empirical
science. If you claim something - you have to prove your
claims experimetally. I am highly sceptical in that issue you've
just described. Only new approach, new experiment proposals,
carefull consideration if those exp make sense and realization
of the most interesting ideas can push our knowledge forward.

Regards

Pawel Karwowski

On Apr 21, 10:44 pm, "Jonathan Thornburg [remove -animal to reply]"
<J.Thornb...@soton.ac-zebra.uk> wrote:

> A recent newspaper story by Dennis Overbye in the New York Timeshttp://www.nytimes.com/2008/04/17/science/space/17dark.html
> (probably needs signup-for-user-tracking-registration to view)
[quoted text clipped - 26 lines]
> as the equations are nonlinear." -- Einstein, fall 1913, discussing
> nonlinear gravitational radiation with Born (quoted in MTW chapter 35)

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Richard Saam - 22 Apr 2008 22:39 GMT

Jonathan Thornburg -remove -animal to reply- wrote:

> A recent newspaper story by Dennis Overbye in the New York Times
> http://www.nytimes.com/2008/04/17/science/space/17dark.html
[quoted text clipped - 21 lines]
> Can anyone point to a more technical account of the claim? Is there
> a preprint out?

RESULTS ON DARK MATTER AND DECAY MODES BY DAMA AT GRAN SASSO
http://arxiv.org/abs/0704.3543
First results from DAMA/LIBRA and the combined results with DAMA/NaI
http://arxiv.org/abs/0804.2741
Dark Matter search
http://arxiv.org/abs/astro-ph/0307403
Rita Bernabei et al
Dip. di Fisica, Università di Roma Tor Vergata and INFN-Roma Tor Vergata,
00133 Roma, Italy

In regards to DAMA observed annual oscillation,
a question comes to mind in terms of the following logic:

Given the statement:

Signature

The Milky Way is moving at around 600 km/s
with respect to the photons of the Cosmic Microwave Background (CMB).
This has been observed by satellites
such as COBE and WMAP as a dipole contribution to the CMB,
as photons in equilibrium at the CMB frame
get blue-shifted in the direction of the motion
and red-shifted in the opposite direction.
--
and also:

--
the solar system is orbiting galactic center at about 200 km/sec
--
and also:

--
the earth has a velocity of 30 km/sec around the sun.
--
and also

--
ref: Dark Matter search
http://arxiv.org/abs/astro-ph/0307403
Fig 10

Harmonic DAMA/NaI experimental data
indicates an annual oscillation of detected radiation flux
detected on earth.
--
Has anyone done the trigonometry in order to calculate
the correlation of annual DAMA/NaI experimental data
on earth due to earth_solar annual differential velocity projection
to CMB velocity vector?

I have found some information to answer the question.
Possibly someone could comment.

The CMB 'hot spot' or 'wind origin' is in constellation Leo

http://aether.lbl.gov/www/projects/u2/

Now the earth moves around the sun at 30 km/sec
The hypothesis would be that average flux would be
when earth - sun line
would be parallel
to earth - Leo line
which occurs September 1 (sun in Leo) and March 1.
with maximum flux (earth against the CMB dipole wind) on December 1
and minimum (CMB dipole wind to earth's back) on June 1.

This is 180 degrees out of phase with your data
but perhaps that is a reflection of dark matter reality

This CMB dipole wind and earth solar rotation
are then approximately 180 degrees of phase with data expressed in:

http://arxiv.org/abs/astro-ph/0307403
Fig 10

http://arxiv.org/abs/0704.3543
Figure 2

where t0 = 152.5 is June 1 (maximum flux)

Is this a coincidence or an indication
of connection between DAMA/NaI observed data and CMB dipole wind.

Richard Saam

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Natural Science Forum / Physics / Research / April 2008

DAMA/Libra claim confirmation of direct dark-matter detection