Cross-disciplinary axion ↔ chameleon detection + ID
DM
Equipment / people
DE
> novel concept
… a by-product
K. Zioutas
University of Patras / Greece
+ O.K. Baker, A. Lindner, Y.K. Semertzidis, A. Upadhye
Benefitted from: CERN, CAST +
M. Betz, P. Brax, F. Caspers, J. Harris, M. Tsagri,
J.-C. Vallet at al. / Tore Supra, L. Walckiers, …
Vistas in Axion Physics: A Roadmap for Theoretical
and Experimental Axion Physics through 2025
UW, Seattle / USA
April 23-26, 2012
1
Related work …
•
CAST search for sub-eV mass solar axions with 3He buffer gas.
The CAST Collaboration, S. Aune et al, Phys. Rev. Lett.107 (2011) 261302
“Results from CAST … searches”, T. Papaevangelou, Moriond (March 2012):
http://indico.in2p3.fr/getFile.py/access?contribId=70&sessionId=11&resId=0&materialId=slides&confId=6001
•
Prospects for Searching Axion-like Particle Dark Matter
with Dipole, Toroidal and Wiggler Magnets
O.K. Baker, M. Betz, F. Caspers, J. Jaeckel, A. Lindner,
A. Ringwald, Y. Semertzidis, P. Sikivie, K. Zioutas, Phys. Rev. D85 (2012) 035018
•
Detection prospects for solar and terrestrial chameleons
P. Brax, A. Lindner, K. Zioutas, Phys. Rev. D85 (2012) 043014.
•
A chameleon helioscope
O.K. Baker, A. Lindner, A. Upadhye, K. Zioutas,
•
arXiv:1201.0079v1
Detection of radiation pressure from solar chameleons
O.K. Baker, A. Lindner, Y.K. Semertzidis, A. Upadhye, K. Zioutas, arXiv:1201.6508v1
… and ref’s therein
2
Axion, Chameleons, WISPs to solve astrophysical puzzles
=>
γ↔ALP oscillations?
•
Dark energy

•
Dark matter
 maxion ~1- 1000 μeV/c2
•
HE  - transparency
 mALP < 10-10 eV/c2 / gaγγ ~ 10-12 GeV-1
mCHameleon = f(density)
Chameleon instead?!
•
WD fast cooling
 maxion ~10 meV/c2
•
Solar corona heating
 maxion ~17 meV/c2
~transparency
•
SN1987A
 maxion ≤10 meV/c2
“Open questions”  new physics?!
3
>> Motivation – encouragement for:
•
Telescopes:
solar / relics
+ Natural T.
 @ work => direct signatures!
 copy their workings
•
RECYCLING
 gain: time, $$, R&D, people (collaborators)
 accelerating science cost efficiently,
e.g., CAST
4
CAST: axion helioscope + …
Axion flux on earth
Ea=4.2 keV
2
g aγ



  10
1 
 10 GeV 
CAST  A superconducting LHC test-dipole tracks the Sun 2x1.5hours @ Sunrise /Sunset.
Operation at T=1.8 K, I=13,000A, B=9T, L=9.26m, 4x14.5 cm2
A difficult experiment: the only moving telescope @ 1.8K (!?)
Expected signal
X-Ray excess during tracking
@ 1-10 keV
CAST sensitivity per detector
0.3 counts/hour for
gaγγ= 10-10 GeV-1 and A = 14.5 cm2
More see in http://indico.in2p3.fr/getFile.py/access?contribId=70&sessionId=11&resId=0&materialId=slides&confId=60015
CAST: Solar axion / chameleon ID
» Signal / Noise
 rare!
Signal + background
The recycled CAST XRTelescope
With CCD at focal plane
expected
axion signal
7
CAST preliminary results for ma > 0.64 eV/c2
… 2012 run
2012
CAST 2012
10 trackings per density step, starting @ 0.4 eV (≈15.5 mbar)
 improved sensitivity
9
CAST: also ~axion haloscope + …
… CHameleon helioscope
•
… tbd
(+ haloscope?)
Relics
CAST  Tore Supra / Tokamak
Need: MW antenna/cavities inside B
 ma ≈ 0.1 – 100 μeV/c2 …tbd
•
Solar axions (CAST)
Need: « X-ray bckg. det’s + XRTs
 best limit for ma <0.02 eV/c2
•
Solar Chameleons
CAST  Tore Supra  new !
Need: ~eV-keV threshold det’s
 best sensitivity
10
CDM axion search
ALPS / DESY
CAST
ADMX
CDM axions / ALPs
11
Alternative magnets as haloscopes
CAST
DESY
Dipole
Wiggler
ATLAS  IAXO
>> experimental Challenge!!
Tore Supra
Toroidal magnets
L. Walckiers / CERN
TE – modes
couple to axions
1st exploratory meeting on
Tore Supra, CERN, 19/3/2012
12
Expected sensitivity
… tbd
Existing bounds for axionlike particles. The QCD-axion region is marked as the hatched band. In the orange
region, axions are a natural candidate for DM. In the lighter shaded orange area, axions can still be DM, but
with decreasing mass, this requires an increasing amount of fine tuning. Axion-like particles can be dark
matter in a large part of the so-far untested parameter space. The right green (red) regions are the
conservatively (realistically) expected sensitivity of a dipole or wiggler search for axion-like particle DM. The
left green/red region shows the masses and couplings that could be probed in a setup with a toroidal magnet.
OK Baker, et al., PRD85 (2012)035018
13
Box-in-the-box principle (3 GHz)
F. Caspers / CERN
Table-top particle physics!
E2-field suppression ~300dB ~10-30
M. Betz, F. Caspers CERN
See M. Betz, in PATRAS2011 http://axion-wimp2011.desy.de/e102694/e102699/e118290/Betz-M.pdf
14
RF cavities inside toroidal magnets
>> Tore Supra
JC Vallet
•
•
Tore Supra = one of the largest Tokamaks
 FREE NOW!!
V = 30 m3 & B = 4.5 T
RF Heating Systems:
- 47-54 MHz : 12 MW x 40s
- 3.7 GHz :
8 MW cw
- 118 GHz :
1 MW x 5s
•
ITER
~2018 completion, start torus pump-down
~10x
F. Caspers / CERN:
“Either with single big cavities for low axion mass ma or with an array of smaller cavities for larger axion masses
>> it’s delicate: each cavity has to be controlled individually, +in terms of its resonance frequency, independently”
>>> tbd

15
Tore Supra
Tokamak, as relics haloscope
The magnetic field converts relic axions to MW photons, which excite the TE011 mode.
The inner walls might have to be covered
by copper sheets, to achieve higher Q
factors and better EMI shielding
The microwave signal is coupled out by a small
antenna and amplified. A commercial spectrum
analyzer can be used to detect the axion signal.
Test
signal
A test signal is required in order to proof that for zero
result the detector was working properly. This test signal
is recommended to be used during the whole run; it
should be near the res-frq but not at resonance.
M. Betz, F. Caspers / CERN
16
Tore Supra
as relics haloscope
Preliminary simulation results
E–field of TE011 mode (ECAV) in TS cavity
•
•
Inner radius: 0.8m, outer radius: 2.4m
TE011 = H011 mode, f = 145.601 MHz
 Most sensitive to axions with
ma = 6∙10-7 eV
Static magnetic field of
superconducting coils (B0)
Wall material
Conductivity
Unloaded Q
Stainless steel
9.8e+5 S/m
19271
Copper
5.8e+7 S/m
148250
17
Tore Supra
as relics haloscope
M. Betz / CERN
Expected sensitivity
With the rather conservative parameters on the
left (QL=1000 & Pdet=5.5∙10-22W), in 9h one could
reach:
Tore Supra
Cavity volume
Magnetic field
Axion density
Geometry factor
Axion mass
Loaded Q factor
Desired signal/noise
System noise temp.
Coupling parameter
Relic axion velocity spread
V
B
pa
C
ma
Q
SNR
Tn
gayy
Qa
Minimum meas. Time
t
t
30300 l
4.5 T
3.00E+02 Mev/cm^3
0.39 Geometry factor
6.00E-07 eV
1.00E+03
2.0
300 K
7.00E-16 GeV^-1
1.00E+06
gaγγ = 7∙10-16 GeV-1
3.18E+04 s
8.8 h
18
Tore Supra
as relics haloscope
• [ADMX]: ~1m3 (low frequency cavity), 7.6T; B2V ~ 50T2m3
 near quantum limit!
• Torre Supra: ~35m3, 4T; B2V~500T2m3
 Low frequency cavity @ ~150MHz  NEW
 Without cavity mode?
F. Caspers / CERN
Higher axion rest mass, in a large volume (Lcoh~10 – 100 m)  lose a factor of
Q~105 in production rate, but wideband!
Y.K. Semertzidis / BNL
 outcome?
19
Tore Supra’…
… relics sensitivity  first estimate
ALPS / DESY
CAST
 ADMX
300K
3K
30mK
19 March 2012
Yannis Semertzidis, BNL
20
Chameleons … to explain DE
Khoury, Weltman 2004
… solar CHameleons!
23
Converted Solar Chameleons: CAST, …, space
0.1 mbar
vacuum
[keV]
CH conversion in vacuum with:
BL=90Tm & βm=106 / βγ=1010.32.
 LE saturation!
In CAST:
CH 
γ
axion  γ
The analogue spectrum [h-1 keV-1] of regenerated photons as predicted
to be seen by CAST: βm=106, B=30T in a shell of width 0.01Rsolar
around the tachocline (~0.7Rsolar).
 Low
Vacuum:
~10-13
~10-17
[keV]
energy threshold: MM, CCD, …?!
+
vacuum
The effective mass of the chameleon inside the CAST pipe
in vacuum is: mch = 40 μeV/c2
24
XRT: Chameleon helioscope
 ~100-1000x enhanced ΦCH !!
Tore Supra

double measurement!!
enter βγ & βm
CAST
Eγ,CH > 50 – 100 eV
X-Ray Telescope = Chameleon telescope
Eγ,CH < 10 – 50 eV
~any Telescope = Chameleon telescope
O.K. Baker , A. Lindner , A. Upadhye , K. Zioutas, arXiv:1201.0079v1 [astro-ph.SR]
27
Detection of radiation pressure from solar chameleons
..on a foil
arXiv:1201.6508v1 [astro-ph.IM]
Equipment?
… Finally, optomechanical experiments might be the mostly sensitive devices
to react on an additional external radiation pressure component like that from
solar chameleons. For example, the measured frequency drifts or the
temporally observed irregularities in Figure 5.9 of [14] are of potential interest to
be followed further; in particular, in case the observed behaviour resembles
solar diurnal behaviour or other solar activity during the time period this
measurement was performed. Therefore, such or other experiments being
sensitive to external radiation pressure, when performed over longer time
periods, i.e. at least one day, a correlation to solar activity should be searched
for. Last but not least, the highest sensitivity of Gravitational Waves antennas
might be of potential interest, provided their unprecedented sensitive
performance is re-considered following the reasoning of this work about an
ubiquitous dark radiation pressure.
.
A new concept!
28
Optical cavity
… with a movable end mirror  ~pendulum.
Mass m & Frequency ωΜ
10-50 nm Membrane, ~50 ngram
~2-3 mm
Pcirc
(r1,t1)
(r2,t2)
Cavity length L ~7mm
31
RT force threshold ≈ 10-16N ≈ 20nW
6nN=1W
Sensitivity ~ 20 nW/cm2 @ RT
ΦsolarCHam. <15 mW/cm2
Jack Harris / Yale U.
 “Contigency”
~106
nanogram - nanometers
? some overlooked signal?
32
Resonant frequency drift … of the membrane in 1 h run.
origin??
“repeatedly”
[Jack Harris/Yale U.]
Solar / celectial CHs!!?
B.M. Zwickl, Progress Toward Observation of Radiation Pressure Shot Noise, PhD-thesis,
Yale University (2011) ( http://www.yale.edu/harrislab/docs/Zwickl_Thesis.pdf ) .
33
Cosmic CHameleons
Optical
IR
same spectrum with
ΦCH ≤ 0.3Φγ-CR
O.K. Baker, K.Z.
…the total probability to ALPs saturates to 1/3,
which is the maximum (theoretical) attenuation.
 Chameleons
http://www.aanda.org/index.php?option=com_article&access=standard&Itemid=129&url=/articles/aa/full/2006/20/aa4446-05/aa4446-05.right.html
H. Dole et al., A&A 451 (2006) 417
36
Thanks Sun!!
37
Back-up slides
31
Tore Supra
as relics haloscope
Can we improve with B2V~500T2m3?
•
Lose a factor of Q~105 in production rate; overall lose a factor
of 3x102 in S/N (for same total integration time). We gain a
factor of 10 in B2V. Hence S/N loss ~30.
•
If the receiver noise is 103 times higher (102 from temperature
and 10 from frequency range)  Another S/N loss of ~30.
•
Then the overall lost factor in S/N is 103. The coupling is worse
by 30-100.
•
Overall the expected sensitivity is ~10-13GeV-1 @ ~10GHz
axion mass range.
19 March 2012
Yannis Semertzidis, BNL
19a
Tore Supra…
Opportunities on both sides, low + high frequency axions.
see O.K. Baker, et al., PRD D85 (2012) 035018
Axion
range
coverage
Central
frequency
[GHz]
Quality
factor Q
Receiver
Axion
noise T [K] coupling
[GeV-1]
5GHz/y
0.150
103
300
2x10-15
5GHz/y
0.150
103
3
2x10-16
5GHz/y
0.150
103
0.03
2x10-17
5GHz/y
10
1
300
10-13
5GHz/y
10
1
3
10-14
5GHz/y
10
1
0.03
10-15
19 March 2012
Yannis Semertzidis, BNL
19b
Maximum energy at which a chameleon particle can be focused by an X-ray mirror with density 10 g/cm3 (≈
the density of a Ni-coated X-ray telescope) and grazing angle ε, for several different chameleon models. The
dotted horizontal and vertical lines illustrate one example of a 600 eV chameleon incident on a mirror of
focusing angle 30', which is, for example, equal to the field-of-view of XMM/Newton. The chameleon will
be focused by this mirror if n=4 and βm=106, but will pass through the mirror if n=1 and βm=104.
K. Baker , A. Lindner , A. Upadhye , K. Zioutas, arXiv:1201.0079v1 [astro-ph.SR]
13
Minimum chameleon energy ω required for transmission through the atmosphere to the Earth’s
surface. The atmosphere has at sea level a density of ρm ≈ 1.2 ·10−3g/cm3. (left) The minimum
energy at normal incidence is the chameleon mass in the atmosphere, shown as a function of βm
and n. (right) Chameleons at nonzero incident angles θ require greater energies for transmission,
i.e., when the chameleons hit the plane of the denser surface less and less perpendicularly, more
and more energetic chameleons can be reflected
K. Baker , A. Lindner , A. Upadhye , K. Zioutas, arXiv:1201.0079v1 [astro-ph.SR]
14
Take for sure B ~0.1pTesla
 BL ~ 109Tm ~ 107xCAST
http://axion-wimp2010.desy.de/e80839/e80847/e92594/100706_montanino.pdf
…the total probability saturates to 1/3  33% of the photons
which is the maximum (theoretical) attenuation.  Chameleons
can convert into ALPs,
E.g.,A. Mirizzi, G. G. Raffelt, P. Serpico, Phys. Rev. D 76, 023001 (2007);
M. A. SANCHEZ-CONDE et al., PHYSICAL REVIEW D 79, 123511 (2009)
http://prd.aps.org/pdf/PRD/v79/i12/e123511
34
although it is well established that the ultimate energy source is the coronal magnetic field,
the question of how the magnetic energy is transformed to heat
the coronal plasma is still to be solved. ... one important issue is
whether the heating is released gradually + continuously or in the form
of discrete, rapid and intense pulses.
http://xxx.lanl.gov/pdf/1204.0041.pdf
April 2012