Solar Solar ~ ~ axions axions K. Zioutas K. Zioutas Università di Patrasso Università di Patrasso & & CERN CERN EU-ILIAS AXIONS EU-ILIAS AXIONS INFN Sezione di Trieste Università di Trieste - Dipartimento di Fisica 3 ottobre 2006 brillante idea brillante idea ! !
Solar ~ axions. K. Zioutas Università di Patrasso & CERN EU-ILIAS AXIONS. brillante idea !. INFN Sezione di Trieste Università di Trieste - Dipartimento di Fisica 3 ottobre 2006. The CAST collaboration. LLNL. - PowerPoint PPT Presentation
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Solar Solar ~~axionsaxions
K. ZioutasK. Zioutas
Università di Patrasso Università di Patrasso && CERN CERN EU-ILIAS AXIONS EU-ILIAS AXIONS
INFN Sezione di TriesteUniversità di Trieste - Dipartimento di Fisica
3 ottobre 2006
brillante ideabrillante idea!!
The CAST collaboration LLNLLLNL
P. SikivieP. Sikivie
IstanbulIstanbul
uu??
E. Arik / TU
M. Asplund / Au
K. Dennerl / MPE
L. Di Lella / CERN
M. Grande / RAL-UK
Th. Hackman / UH-FI
D.H.H. Hoffmann / TU-Darmstadt
J. Huovelin / UH-FI
J. Jacoby / U. Frankfurt B. Lakic / RBI - Zagreb
S. Orlando / INAF-Palermo
A. Ortiz / USA
Th. Papaevangelou / CERN
Y. Semertzidis / BNL-USA
Sp. Tzamarias / HOU-GR
O. Vilhu / UH-FI
….m.m.
Profit / encouraged from :
CASTCAST motivated workmotivated work
beyond(?) beyond(?) CASTCAST feedbackfeedback!!
Thanks to PVLAS:Axion searches in the spotlight
Attempts to Attempts to reconcile PVLAS reconcile PVLAS result with CAST result with CAST and other limits…and other limits…
And others…And others…
Axion searches in the spotlight
• The interest on axions reaches also The interest on axions reaches also string theorists…string theorists…
22ndnd X-ray optic X-ray optic • Measured effective area (throughput) very different than simulations• Several factors at play
mimic CAST
(in)direct axion-signals ?
Challenging questions @ Sun
11 years cycle!?
Solar corona heating
Flares instantaneous particle acceleration
Dynamo(s) B⊙
Sunspots heating
Neon composition “Solar Model problem”“Solar Model problem”!
» smoking-gun signatures for new physics?
solarsolar ~~axionsaxions
ubiquitous @@ Sun, …
11st st
┌►┌► X-rays, visible, …
Unexpected (dis)appearance of photonsUnexpected (dis)appearance of photons
Lx ~ B2 à la Sikivie ~ ρ à la van Bibber
dynamical behaviour transient effects
axion ⇄ photon oscillations
22ndnd axion → 2γ
decay of gravitationally trapped massive ~axions, e.g. KK-type generic
▼ unexpectedly hot “plasma” ▼ Lx ≈ constant
solar observations require both componentssolar observations require both components
solar corona problem Grotrian (1939) The enigma of coronal heating represents… one of the outstanding puzzles of stellar astronomy + one of the most challenging problems in astrophysics. S.M. Jefferies, McIntosh, Armstrong, Bogdan, Cacciani, Fleck, ApJL. 648 (10.9.2006)151 E R Priest, D W Longcope, J Heyvaerts, ApJ. 624 (2005)
1057
Solar temperature distribution
Stellar observations + theory on stellar evolution
↛ stars might possess atmospheres … that produce X-rays.L.W. Acton, Magnetodynamic Phenomena in the Solar Atm. (1996) 3
K. Galsgaard, C.E. Parnell, A.& A. 439 (August 2005) 335 R.B. Dahlburg, J.A. Klimchuk, S.K. Antiochos, ApJ. 622 (2005) 1191
The magnetic field plays a crucial role in heating the solar corona (this has been known for many years) the exact energy release mechanism(s) is(are) still unknown.
the process by which it is converted into heat and other forms remains a nagging unsolved problem.
Values in 3-12 keV correlate with GOES implying signal!
How is this energetic e-- population created in the Quiet Corona ? more offpointing 2006 thru 2007
not ≠ reconstructed solar X-ray spectrum see DiLella + Z. (2003)
20062006
What produces solar flaresWhat produces solar flares? ? μμflares, nanoflares,..flares, nanoflares,..
The precise causes of solar flares & CMEs is one of the great solar mysteries. (20032003)
flare-quiet ≈≈ flare-imminent regions
↓↓ … storage and release of the energy that powers solar flares is generally believedbelieved to be in the coronal magnetic fieldmagnetic field … + magnetic reconnectionmagnetic reconnection necessary for solar flares to occur.
One key issue to understand the coronal heating problem is to know howhow magnetic energy can be stored and then released in a solar magnetic configuration.
S Regnier, RC Canfield, Proc. SOHO 15 Workshop - Coronal Heating,
St. Andrews, Scotland, 6-9 September 2004, ESA SP-575 (2004) 255
the magnetic field can transform out streaming
~axions-to-photons + vice versavice versa
++ transient brightenings!
In the axion scenarioIn the axion scenario
B B = catalyst = catalyst ⊗⊗ ρρlocal,local,ΔΔtt ~ ~ ωωplasmaplasma=m=maxionaxion
CASTCAST @@ SunSun
<X-ray flux> / cm2 vs. <B> July-Nov. 1996
From: L. van Driel-Gesztelyi, P. Démoulin, C.H. Mandrini, L. Harra, J.A. Klimchuk, ApJ. 586 (2003) 579
K. Zioutas, K. Dennerl, M. Grande, D.H.H. Hoffmann, J. Huovelin, B. Lakic, S. Orlando, A.Ortiz,
Th. Papaevangelou, Y. Semertzidis, Sp. Tzamarias, O. Vilhu J. Phys. Conf. Ser. 39 (2006) 103
The long-term evolution of AR 7978 (S10o) Yohkoh / SXT
Lx B1.94±.12
~ filter independent
Eγ < 4 keV
B [Gauss]
Lx
11stst
RHESSI :often hard X-rayemission from non-flaring ARs.
The relation between the solar soft X-ray flux (below ~4.4keV) …and B can be approximated by a power law with an averaged index close to 2. Benevolenskaya, Kosovichev, Lemen, Scherrer, Slater ApJ. 571 (2002) L181
Note: axion-to-photon oscillation ∝ B2 e.g., in CAST
DHH Hoffmann, K. Z., Nucl. Phys. B Suppl. 151 (2006) 359
11 years solar cycle11 years solar cycle??
22ndnd
33rdrd
Rebinned peak flare X-ray intensity vs. Bmax
D. Mason et al., ApJ. 645 (10.7.2006)1543 B2 correlation
Lx
↑
Bmax
The Electron “Problem”The Electron “Problem”
e- flux~105 hard X-raysfrom Bremsstrahlung!!
FLARES FLARES origin?origin?
G. Emslie (20052005)http://www.astro.auth.gr/%7Evlahos/ascona/memberstalks/energeticsEmslie.ppt#366,8
44ththSUNSPOTSSUNSPOTS originorigin??
K. Zioutas, K. Dennerl, M. Grande, D.H.H. Hoffmann, J. Huovelin, B. Lakic, S. Orlando, A.Ortiz, Th. Papaevangelou, Y. Semertzidis, Sp. Tzamarias, O. Vilhu J. Phys. Conf. Ser. 39(2006)103
rela
tive
to
Ph
oto
sph
ere
(=Q
uie
t S
un
)
50% of the quiet Sun
SK Solanki A.&A. Rev.11 (2003) 153 Plot reconstructed from : • fundamental questions remain unanswered.fundamental questions remain unanswered.• is an additional mechanism neededis an additional mechanism needed??
SUNSPOTS Yohkoh - XRTelescope
<1.3 MK> quiet Sun
<1.8 MK> Umbra
Temperature distributions A.Nindos, M.R.Kundu, S.M.White, K.Shibasaki, N.Gopalswamy,
Long-lasting sunspots appear in this sequence of drawings made by
Galileo himself as he observed the Sun from June 2nd to 26th, 16121612. http://science.nasa.gov/headlines/y2001/ast07nov_1.htm
more?
manifestation of 2 opposite effectsmanifestation of 2 opposite effects??
Solar metallicitySolar metallicity
Standard Solar Model problem with:Standard Solar Model problem with:
Ne/O abundance ratios vs. coronal activity.
To rescue the agreement between the SSModel and Helioseismology the radiative opacity reduction by the downward revision of the C,N,O,Ne abundances (which provide a major source of opacity for the solar interior, which determines the internal solar structure and the depth of the convection zone) must be compensated by other elements. Ne is the only suitable element, since its photospheric abundance is not well determined due to absence of strong lines; the Ne solar abundance is obtained either from solar energetic particles or from coronal X-rays or EUV. Also above 20 quiet solar Active Regions:
Quiet ARs:Quiet ARs: Ne/ONe/O also at ~0.15 also at ~0.15..Flares:Flares: enhanced Ne detection enhanced Ne detection (~2x),
i.e., some mechanism would preferen-tially dredge up Ne from the photosphere!Ne/O = 0.52 would reconcile low C,N,O abundances with helioseismology.Solution: stellar values!?The problem: find a truly solar-like star. None star known has such a low Ne/O ratio as observed for the Sun. Why the Sun is so specialWhy the Sun is so special??
C.Liefke, JHMM. Schmitt, A&A L. (2006)
models incorrectly predict • the depth of the convection zone, • the depth profiles of sound speed and density, • the helium abundance J.J. Drake, P. Testa, Nature 436 (2005) 525
Stellar spectra are likely dominated by photons fromintense flares. Therefore flare enhanced Ne/O ratios no solution of the problem! J.T. Schmelz et al., ApJ. 634 (2005) L197
measured photospheric abundances of
C, N, O, Ne 25-35% below prediction!
M. Asplund et al., astro-ph/200410214 :
!!Solar axion surface effects at workSolar axion surface effects at work!!
… changing diffusion locally.
No problem for the Solar Model
Martin ASPLUND, private communication, 11/9/2006
“the most promising aspect in my opinion is not the increase in radiation pressure, but rather the extra heating from absorption the extra heating from absorption of axions in the atmosphere which might increase the of axions in the atmosphere which might increase the temperature in the spectral line formation region of the Sun.” temperature in the spectral line formation region of the Sun.”
▼▼
• Solar atmosphere:Solar atmosphere: differential rotation
• SolarSolar ν’ν’s s && X X--raysrays oscillations / correlations
WL K-Corona?
mm
Soft X-ray Corona
photosphere
The rotation profile across latitude for all years averaged. Short solid line: sunspot groups; thin solid line: Mt. Wilson Doppler measurements of the photosphere; dashed line: the WL K-corona.
M.A. Weber, L.W. Acton, D. Alexander, S. Kubo, H. Hara, Sol. Phys. 189 (1999) 271
Why this occurs is unclear!D. Altrock, Private communication
Comparison of normalized probability distribution functions formed from power spectra of data from SXT equator (red), SXT N60-S60 (green), Homestake (black), and GALLEX (blue). Note that the SXT (red) and GALLEX data are equatorial, and the other two are not. Frequencies are given in cycles per year.
Comparison of normalized probability distribution functions formed from power spectra of data from SXT equator (red), SXT N60-S60 (green), Homestake (black), and GALLEX (blue). Note that the SXT (red) and GALLEX data are equatorial, and the other two are not. Frequencies are given in cycles per year.