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Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, 17-21 Sept 2008, Beijing, China Neutrinos and the stars.

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Presentation on theme: "Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, 17-21 Sept 2008, Beijing, China Neutrinos and the stars."— Presentation transcript:

1 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Neutrinos and the stars Neutrinos and the Stars Georg Raffelt, MPI for Physics Lectures at the Topical Seminar Neutrino Physics & Astrophysics Sept 2008, Beijing, China Georg Raffelt, MPI for Physics Lectures at the Topical Seminar Neutrino Physics & Astrophysics Sept 2008, Beijing, China

2 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Where do Neutrinos Appear in Nature? Astrophysical Accelerators Soon ? Cosmic Big Bang (Today 330 /cm 3 ) Indirect Evidence Indirect Evidence Nuclear Reactors Particle Accelerators Particle Accelerators Earth Atmosphere (Cosmic Rays) Sun Supernovae (Stellar Collapse) SN 1987A SN 1987A Earth Crust (NaturalRadioactivity)

3 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Where do Neutrinos Appear in Nature? Neutrinos from nuclear reactions: Energies 1 20 MeV Quasi thermal sources Supernova: T ~ few MeV Big-Bang Neutrinos: Very small energies today (cosmic red shift) Like matter today Beam dump neutrinos High-energy protons hit High-energy protons hit matter or photons matter or photons Produce secondary Produce secondary Neutrinos from pion Neutrinos from pion decay decay e e e e Energies GeV Energies GeV

4 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Where do Neutrinos Appear in Nature? Low-energy neutrino astronomy (including geo-neutrinos) Energies ~ 1 50 MeV Long-baseline neutrino oscillation experiments with Reactor neutrinos Reactor neutrinos Neutrino beams from Neutrino beams from accelerators accelerators High-energy neutrino astronomy Closely related to cosmic-ray physics Precision cosmology & Precision cosmology & limit on neutrino mass limit on neutrino mass Big-bang nucleosynthesis Big-bang nucleosynthesis Leptogenesis Leptogenesis

5 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Hans Bethe ( , Nobel prize 1967) Thermonuclear reaction chains (1938) Neutrinos from the Sun Solar radiation: 98 % light 2 % neutrinos 2 % neutrinos At Earth 66 billion neutrinos/cm 2 sec Reaction-chains Energy 26.7 MeV Helium

6 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Bethes Classic Paper on Nuclear Reactions in Stars No neutrinos from nuclear reactions in 1938 …

7 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Gamow & Schoenberg, Phys. Rev. 58:1117 (1940)

8 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Gamow & Schoenberg 2

9 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Sun Glasses for Neutrinos? Several light years of lead Several light years of lead needed to shield solar needed to shield solar neutrinos neutrinos Bethe & Peierls 1934: Bethe & Peierls 1934: … this evidently means … this evidently means that one will never be able that one will never be able to observe a neutrino. to observe a neutrino. 8.3 light minutes

10 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China First Detection ( ) Fred Reines (1918 – 1998) Nobel prize 1995 Clyde Cowan (1919 – 1974) Detector prototype Anti-ElectronNeutrinosfromHanford Nuclear Reactor 3 Gammas in coincidence pp nn CdCd e+e+e+e+ e+e+e+e+ e-e-e-e- e-e-e-e-

11 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Inverse beta decay of chlorine 600 tons of Perchloroethylene Homestake solar neutrino Homestake solar neutrino observatory ( ) observatory ( ) First Measurement of Solar Neutrinos

12 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Neutrinos from the Sun Solar Neutrinos

13 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China < MeV MeV MeV PP-I < 18.8 MeV hep MeV MeV < 15 MeV PP-IIPP-III Hydrogen burning: Proton-Proton Chains 15%85% 0.02%90%10% 0.24%100%

14 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Solar Neutrino Spectrum

15 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Hydrogen Burning: CNO Cycle (p, )

16 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China John Bahcall Raymond Davis Jr Missing Neutrinos from the Sun Homestake Chlorine 7 Be 8B8B8B8B CNO Measurement (1970 – 1995) Calculation of expected experimental counting rate from various source reactions

17 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Results of Chlorine Experiment Average ( ) stat 0.16 sys SNU (SNU = Solar Neutrino Unit = 1 Absorption / sec / Atoms) Theoretical Prediction 6 9 SNU Solar Neutrino Problem since 1968 AverageRate

18 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Neutrino Flavor Oscillations Two-flavor mixing Bruno Pontecorvo (1913 – 1993) Invented nu oscillations Each mass eigenstate propagates as with Phase difference implies flavor oscillations OscillationLength sin 2 (2 ) Probability e Probability e z

19 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Cherenkov Effect Water Elastic scattering or CC reaction Neutrino LightLight Cherenkov Ring Electron or Muon (Charged Particle)

20 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Super-Kamiokande Neutrino Detector 42 m 39.3 m

21 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Super-Kamiokande: Sun in the Light of Neutrinos

22 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China 2002 Physics Nobel Prize for Neutrino Astronomy Ray Davis Jr. ( ) Masatoshi Koshiba (*1926) for pioneering contributions to astrophysics, in particular for the detection of cosmic neutrinos particular for the detection of cosmic neutrinos

23 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Solar Neutrino Spectrum 7-Be line measured by Borexino (since 2007)

24 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Solar Neutrino Spectroscopy with BOREXINO Neutrino electron scattering Neutrino electron scattering Liquid scintillator technology Liquid scintillator technology (~ 300 tons) (~ 300 tons) Low energy threshold Low energy threshold (~ 60 keV) (~ 60 keV) Online since 16 May 2007 Online since 16 May 2007 Expected without flavor oscillationsExpected without flavor oscillations 75 ± 4 counts/100t/d Expected with oscillationsExpected with oscillations 49 ± 4 counts/100t/d BOREXINO result (May 2008)BOREXINO result (May 2008) 49 ± 3 stat ± 4 sys cnts/100t/d arXiv: (25 May 2008) arXiv: (25 May 2008)

25 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Next Steps in Borexino Collect more statistics of Beryllium line Collect more statistics of Beryllium line Seasonal variation of rate Seasonal variation of rate (Earth orbit eccentricity) (Earth orbit eccentricity) Measure neutrinos from the CNO reaction chain Measure neutrinos from the CNO reaction chain Information about solar metal abundance Information about solar metal abundance Measure geo-neutrinos Measure geo-neutrinos (from natural radioactivity in the Earth crust) (from natural radioactivity in the Earth crust) Approx events/year Approx events/year Main background: Reactors ~ 20 events/year Main background: Reactors ~ 20 events/year

26 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Geo Neutrinos: Why and What? We know surprisingly little about the interior of the Earth: Deepest bore hole ~ 12 km Deepest bore hole ~ 12 km Samples from the crust are Samples from the crust are available for chemical analysis available for chemical analysis (e.g. vulcanoes) (e.g. vulcanoes) Seismology reconstructs density Seismology reconstructs density profile throughout the Earth profile throughout the Earth Heat flow from measured Heat flow from measured temperature gradients TW temperature gradients TW (BSE canonical model, based on (BSE canonical model, based on cosmo-chemical arguments, cosmo-chemical arguments, predicts ~ 19 TW from crust and predicts ~ 19 TW from crust and mantle, none from core) mantle, none from core) Neutrinos escape freely Neutrinos escape freely Carry information about chemical composition, radioactive heat production, Carry information about chemical composition, radioactive heat production, or even a putative natural reactor at the core or even a putative natural reactor at the core

27 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Expected Geo Neutrino Fluxes S. Dye, Talk 5/25/2006 Baltimore

28 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Geo Neutrinos Predicted geo neutrino flux Reactor background KamLAND scintillator detector (1 kton)

29 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Kamland Observation of Geoneutrinos First tentative observation of geoneutrinos First tentative observation of geoneutrinos at Kamland in 2005 (~ 2 sigma effect) at Kamland in 2005 (~ 2 sigma effect) Very difficult because of large background Very difficult because of large background of reactor neutrinos of reactor neutrinos (is main purpose for neutrino oscillations) (is main purpose for neutrino oscillations)

30 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Neutrinos from the Sun Solar Models

31 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Equations of Stellar Structure Assume spherical symmetry and static structure (neglect kinetic energy) Assume spherical symmetry and static structure (neglect kinetic energy) Excludes: Rotation, convection, magnetic fields, supernova-dynamics, … Excludes: Rotation, convection, magnetic fields, supernova-dynamics, … Literature Clayton: Principles of stellar evolution and Clayton: Principles of stellar evolution and nucleosynthesis (Univ. Chicago Press 1968) nucleosynthesis (Univ. Chicago Press 1968) Kippenhahn & Weigert: Stellar structure Kippenhahn & Weigert: Stellar structure and evolution (Springer 1990) and evolution (Springer 1990) Hydrostatic equilibrium Hydrostatic equilibrium Energy conservation Energy conservation Energy transfer Energy transfer rP G N M r L r Radius from center Pressure Newtons constant Mass density Integrated mass up to r Luminosity (energy flux) Local rate of energy generation [erg/g/s] Opacity Radiative opacity Electron conduction

32 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Convection in Main-Sequence Stars Kippenhahn & Weigert, Stellar Structure and Evolution Sun

33 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Virial Theorem and Hydrostatic Equilibrium Most important tool to understand Most important tool to understand self-gravitating systems self-gravitating systems Hydrostatic equilibrium Hydrostatic equilibrium Average energy of single atoms of the gas Virial Theorem L.h.s. partial integration with P = 0 at surface R Integrate both sides Integrate both sides Classical monatomic gas: (U density of internal energy)

34 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Virial Theorem Applied to the Sun Virial Theorem Virial Theorem Approximate Sun as a homogeneous sphere with Mass Mass Radius Radius Gravitational potential energy of a proton near center of the sphere Thermal velocity distribution Estimated temperature T = 1.1 keV T = 1.1 keV Central temperature from standard solar models

35 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Constructing a Solar Model: Fixed Inputs Solve stellar structure equations with good microphysics, starting from a Solve stellar structure equations with good microphysics, starting from a zero-age main-sequence model (chemically homogeneous star) to present age zero-age main-sequence model (chemically homogeneous star) to present age Adapted from A. Serenellis lectures at Scottish Universities Summer School in Physics 2006 Fixed quantities Solar mass M = g 0.1% Keplers 3 rd law Solar age t = yrs 0.5%Meteorites Quantities to match Solar luminosity L = erg s % Solar constant Solar radius R = cm 0.1% Angular diameter Solar metals/hydrogen ratio (Z/X) = Photosphere and meteorites

36 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Constructing a Solar Model: Free Parameters Adapted from A. Serenellis lectures at Scottish Universities Summer School in Physics free parameters Convection theory has 1 free parameter: Convection theory has 1 free parameter: Mixing length parameter a MLT Mixing length parameter a MLT determines the temperature stratification where convection determines the temperature stratification where convection is not adiabatic (upper layers of solar envelope) is not adiabatic (upper layers of solar envelope) 2 of the 3 quantities determining the initial composition: 2 of the 3 quantities determining the initial composition: X ini, Y ini, Z ini (linked by X ini + Y ini + Z ini = 1). X ini, Y ini, Z ini (linked by X ini + Y ini + Z ini = 1). Individual elements grouped in Z ini have relative abundances Individual elements grouped in Z ini have relative abundances given by solar abundance measurements (e.g. GS98, AGS05) given by solar abundance measurements (e.g. GS98, AGS05) Construct a 1 M initial model with X ini, Z ini, (Y ini = 1 – X ini Z ini ) Construct a 1 M initial model with X ini, Z ini, (Y ini = 1 – X ini Z ini ) and a MLT and a MLT evolve it for the solar age t evolve it for the solar age t match (Z/X), L and R to better than one part in 10 5 match (Z/X), L and R to better than one part in 10 5

37 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Standard Solar Model Output Information Eight neutrino fluxes: production profiles and integrated values. Only 8 B flux directly measured (SNO) so far Chemical profiles X(r), Y(r), Z i (r) electron and neutron density profiles electron and neutron density profiles (needed for matter effects in neutrino studies) Thermodynamic quantities as a function of radius: T, P, density ( ), sound speed (c) Surface helium abundance Y surf (Z/X and 1 = X + Y + Z leave 1 degree of freedom) Depth of the convective envelope, R CZ Adapted from A. Serenellis lectures at Scottish Universities Summer School in Physics 2006

38 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Standard Solar Model: Internal Structure TemperatureDensity

39 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Neutrinos from the Sun Helioseismology and the New Opacity Problem New Opacity Problem

40 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Helioseismology: Sun as a Pulsating Star Discovery of oscillations: Leighton et al. (1962) Sun oscillates in > 10 5 eigenmodes Frequencies of order mHz (5-min oscillations) Individual modes characterized by radial n, angular l and longitudinal m numbers Adapted from A. Serenellis lectures at Scottish Universities Summer School in Physics 2006

41 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Helioseismology: p-Modes Solar oscillations are acoustic waves (p-modes, pressure is the restoring force) stochastically excited by convective motions Outer turning-point located close to temperature inversion layer Inner turning-point varies, strongly depends on l (centrifugal barrier) Credit: Jørgen Christensen-Dalsgaard

42 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China + Examples for Solar Oscillations + =

43 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Helioseismology: Observations Adapted from A. Serenellis lectures at Scottish Universities Summer School in Physics 2006 Doppler observations of spectral Doppler observations of spectral lines measure velocities of lines measure velocities of a few cm/s a few cm/s Differences in the frequencies Differences in the frequencies of order mHz of order mHz Very long observations needed. Very long observations needed. BiSON network (low-l modes) BiSON network (low-l modes) has data for 5000 days has data for 5000 days Relative accuracy in frequencies Relative accuracy in frequencies

44 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Helioseismology: Comparison with Solar Models Oscillation frequencies depend on, P, g, c Oscillation frequencies depend on, P, g, c Inversion problem: Inversion problem: From measured frequencies and from a reference solar model From measured frequencies and from a reference solar model determine solar structure determine solar structure Output of inversion procedure: c 2 (r), (r), R CZ, Y SURF Output of inversion procedure: c 2 (r), (r), R CZ, Y SURF Relative sound-speed difference between helioseismological model and standard solar model

45 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China New Solar Opacities (Asplund, Grevesse & Sauval 2005) Large change in solar composition: Large change in solar composition: Mostly reduction in C, N, O, Ne Mostly reduction in C, N, O, Ne Results presented in many papers by the Asplund group Results presented in many papers by the Asplund group Summarized in Asplund, Grevesse & Sauval (2005) Summarized in Asplund, Grevesse & Sauval (2005) Authors (Z/X) (Z/X) Main changes (dex) Grevesse Anders & Grevesse C = 0.1, N = 0.06 C = 0.1, N = 0.06 Grevesse & Noels Grevesse & Sauval C = 0.04, N = 0.07, O = 0.1 C = 0.04, N = 0.07, O = 0.1 Asplund, Grevesse & Sauval C = 0.13, N = 0.14, O = 0.17 Ne = 0.24, Si = 0.05 C = 0.13, N = 0.14, O = 0.17 Ne = 0.24, Si = 0.05 (affects meteoritic abundances) Adapted from A. Serenellis lectures at Scottish Universities Summer School in Physics 2006

46 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Origin of Changes Improved modeling Improved modeling 3D model atmospheres 3D model atmospheres MHD equations solved MHD equations solved NLTE effects accounted for in most cases NLTE effects accounted for in most cases Improved data Improved data Better selection of spectral lines Better selection of spectral lines Previous sets had blended lines Previous sets had blended lines (e.g. oxygen line blended with nickel line) (e.g. oxygen line blended with nickel line) Spectral lines Spectral lines from solar from solar photosphere photosphere and corona and corona Meteorites Meteorites Volatile elements Volatile elements do not aggregate easily into solid bodies do not aggregate easily into solid bodies e.g. C, N, O, Ne, Ar only in solar spectrum e.g. C, N, O, Ne, Ar only in solar spectrum Refractory elements, Refractory elements, e.g. Mg, Si, S, Fe, Ni e.g. Mg, Si, S, Fe, Ni both in solar spectrum and meteorites both in solar spectrum and meteorites meteoritic measurements more robust meteoritic measurements more robust

47 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Consequences of New Element Abundances Much improved modeling Much improved modeling Different lines of same element give Different lines of same element give same abundance (e.g. CO and CH lines) same abundance (e.g. CO and CH lines) Sun has now similar composition Sun has now similar composition to solar neighborhood to solar neighborhood What is good What is good New problems New problems Agreement between helioseismology Agreement between helioseismology and SSM very much degraded and SSM very much degraded Was previous agreement a coincidence? Was previous agreement a coincidence? Adapted from A. Serenellis lectures at Scottish Universities Summer School in Physics 2006

48 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Standard Solar Model 2005: Old and New Opacity Sound Speed Density Old: BS05 (GS98) New: BS05 (ASG05) Helioseismology R CZ ± Y SURF ± Adapted from A. Serenellis lectures at Scottish Universities Summer School in Physics 2006

49 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Old and New Neutrino Fluxes Old: BS05 (GS98) New: BS05 (AGS05) Measurement (SNO) Flux cm 2 s 1 Error%Flux Error%Flux Error% pp pp pep pep hep hep Be 7 Be B8B8B8B N O F Cl (SNU) Ga (SNU) Bahcall, Serenelli & Basu (astro-ph/ & astro-ph/ )

50 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Neutrinos from the Sun Very Low-Energy Solar Neutrinos

51 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Neutrinos from Thermal Plasma Processes These processes first discussed in after V A theory Photo (Compton) Plasmon decay Pair annihilation Bremsstrahlung

52 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Solar Neutrinos from Compton Process Cross section (non-relativistic limit) Volume energy loss rate Energy loss rate per unit mass To be compared with nuclear energy generation rate in the Sun Photo (Compton)

53 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Thermal vs. Nuclear Neutrinos from the Sun Haxton & Lin, The very low energy solar flux of electron and heavy-flavor neutrinos and anti-neutrinos, nucl-th/

54 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Neutrinos from the Sun Search for Solar Axions

55 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Search for Solar Axions a Sun Primakoffproduction Axion Helioscope (Sikivie 1983) Magnet S N a Axion-Photon-Oscillation Tokyo Axion Helioscope (Sumico) Tokyo Axion Helioscope (Sumico) (Results since 1998, up again 2008) (Results since 1998, up again 2008) è CERN Axion Solar Telescope (CAST) (Data since 2003) (Data since 2003) Axion flux Axion flux Alternative technique: Alternative technique: Bragg conversion in crystal Bragg conversion in crystal Experimental limits on solar axion flux Experimental limits on solar axion flux from dark-matter experiments from dark-matter experiments (SOLAX, COSME, DAMA,...) (SOLAX, COSME, DAMA,...)

56 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Tokyo Axion Helioscope (Sumico) S.Moriyama, M.Minowa, T.Namba, Y.Inoue, Y.Takasu & A.Yamamoto, PLB 434 (1998) 147 ~ 3 m

57 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China LHC Magnet Mounted as a Telescope to Follow the Sun

58 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China CAST at CERN

59 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Limits from CAST-I and CAST-II CAST-I results: PRL 94: (2005) and JCAP 0704 (2007) 010 CAST-II results (He-4 filling): preliminary

60 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Neutrinos from the Sun High-Energy Neutrinos from the Sun

61 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Search for WIMP Dark Matter Direct Method (Laboratory Experiments) Crystal Energydeposition Recoil energy (few keV) is measured by Ionisation Ionisation Scintillation Scintillation Cryogenic Cryogenic Galactic dark matter particle(e.g.neutralino) Indirect Method (Neutrino Telescopes) Sun Sun Galactic dark matterparticles are accreted AnnihilationHigh-energyneutrinos(GeV-TeV) can be measured

62 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China IceCube Neutrino Telescope at the South Pole 1 km 3 antarctic ice, instrumented 1 km 3 antarctic ice, instrumented with 4800 photomultipliers with 4800 photomultipliers 40 of 80 strings installed (2008) 40 of 80 strings installed (2008) Completion until 2011 foreseen Completion until 2011 foreseen

63 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Muon Flux from WIMP Annihilation in the Sun

64 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China High-Energy Neutrinos from the Sun Ingelman & Thunman, High Energy Neutrino Production by Ingelman & Thunman, High Energy Neutrino Production by Cosmic Ray Interactions in the Sun [hep-ph/ ]

65 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Neutrinos (and other Particles) from the Sun Thermal plasma reactions E ~ 1 eV - 30 keV E ~ 1 eV - 30 keV No apparent way to measure No apparent way to measure Nuclear burning reactions E ~ MeV E ~ MeV Routine detailed measurements Routine detailed measurements Cosmic-ray interactions in the Sun E ~ GeV E ~ GeV Future high-E neutrino telescopes (?) Future high-E neutrino telescopes (?) Dark matter annihilation in the Sun E ~ GeV - TeV (?) E ~ GeV - TeV (?) Future high-E neutrino telescopes (?) Future high-E neutrino telescopes (?) New particles, notably axions Are searched with CAST & Sumico Are searched with CAST & Sumico

66 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Basics of Stellar Evolution

67 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Equations of Stellar Structure Assume spherical symmetry and static structure (neglect kinetic energy) Assume spherical symmetry and static structure (neglect kinetic energy) Excludes: Rotation, convection, magnetic fields, supernova-dynamics, … Excludes: Rotation, convection, magnetic fields, supernova-dynamics, … Literature Clayton: Principles of stellar evolution and Clayton: Principles of stellar evolution and nucleosynthesis (Univ. Chicago Press 1968) nucleosynthesis (Univ. Chicago Press 1968) Kippenhahn & Weigert: Stellar structure Kippenhahn & Weigert: Stellar structure and evolution (Springer 1990) and evolution (Springer 1990) Hydrostatic equilibrium Hydrostatic equilibrium Energy conservation Energy conservation Energy transfer Energy transfer rP G N M r L r Radius from center Pressure Newtons constant Mass density Integrated mass up to r Luminosity (energy flux) Local rate of energy generation [erg/g/s] Opacity Radiative opacity Electron conduction

68 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Nuclear Binding Energy Mass Number Fe

69 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Thermonuclear Reactions and Gamow Peak Coulomb repulsion prevents nuclear reactions, except for Gamow tunneling Tunneling probability With Sommerfeld parameter Parameterize cross section with astrophysical S-factor LUNA Collaboration, nucl-ex/

70 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Main Nuclear Burnings Hydrogen burning 4p + 2e 4 He + 2 e Proceeds by pp chains and CNO cycle Proceeds by pp chains and CNO cycle No higher elements are formed because No higher elements are formed because no stable isotope with mass number 8 no stable isotope with mass number 8 Neutrinos from p n conversion Neutrinos from p n conversion Typical temperatures: 10 7 K (~1 keV) Typical temperatures: 10 7 K (~1 keV) Helium burning 4 He + 4 He + 4 He 8 Be + 4 He 12 C 4 He + 4 He + 4 He 8 Be + 4 He 12 C Triple alpha reaction because 8 Be unstable, builds up with concentration ~ C + 4 He 16 O 12 C + 4 He 16 O 16 O + 4 He 20 Ne 16 O + 4 He 20 Ne Typical temperatures: 10 8 K (~10 keV) Carbon burning Many reactions, for example 12 C + 12 C 23 Na + p or 20 Ne + 4 He etc 12 C + 12 C 23 Na + p or 20 Ne + 4 He etc Typical temperatures: 10 9 K (~100 keV) Each type of burning occurs Each type of burning occurs at a very different T but a at a very different T but a broad range of densities broad range of densities Never co-exist in the same Never co-exist in the same location location

71 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Hydrogen Exhaustion in a Main-Sequence Star Helium-burning star HeliumBurning HydrogenBurning Main-sequence star Hydrogen Burning

72 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Burning Phases of a 15 Solar-Mass Star Hydrogen3 H He Duration[years] L /L L /L c [g/cm 3 ] T c [keV]DominantProcess Burning Phase L [10 4 L sun ] Helium14 He C, O Carbon C Ne, Mg Neon Ne O, Mg Oxygen O Si Silicon Si Fe, Ni days 6 days

73 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Neutrinos from Thermal Plasma Processes These processes first discussed in after V A theory Photo (Compton) Plasmon decay Pair annihilation Bremsstrahlung

74 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Neutrino Energy Loss Rates

75 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Existence of Direct Neutrino-Electron Coupling

76 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Self-Regulated Nuclear Burning Main-Sequence Star Small Contraction Heating Heating Increased nuclear burning Increased nuclear burning Increased pressure Increased pressure Expansion Expansion Additional energy loss (cooling) Loss of pressure Loss of pressure Contraction Contraction Heating Heating Increased nuclear burning Increased nuclear burning Hydrogen burning at a nearly fixed T Gravitational potential nearly fixed: Gravitational potential nearly fixed: G N M/R ~ constant G N M/R ~ constant R M (More massive stars bigger) R M (More massive stars bigger) Virial Theorem Virial Theorem

77 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Degenerate Stars (White Dwarfs) Assume T very small No thermal pressure No thermal pressure Electron degeneracy is pressure source Electron degeneracy is pressure source Pressure ~ Momentum density x Velocity Electron density Electron density Momentum p F (Fermi momentum) Momentum p F (Fermi momentum) Velocity Velocity Pressure Pressure Density Density (Stellar mass M and radius R) (Stellar mass M and radius R) Hydrostatic equilibrium With dP/dr ~ P/R we have approximately (Y e electrons per nucleon) (Y e electrons per nucleon) For sufficiently large mass, electrons become relativistic Velocity = speed of light Velocity = speed of light Pressure Pressure No stable configuration Chandrasekhar mass limit Inverse mass-radius relationship Inverse mass-radius relationship for degenerate stars: R M 1/3 for degenerate stars: R M 1/3

78 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Degenerate Stars (White Dwarfs) Inverse mass-radius relationship Inverse mass-radius relationship for degenerate stars: R M 1/3 for degenerate stars: R M 1/3 Chandrasekhar mass limit

79 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Stellar Collapse Helium-burning star HeliumBurning HydrogenBurning Main-sequence star Hydrogen Burning Onion structure Degenerate iron core: 10 9 g cm g cm 3 T K T K M Fe 1.5 M sun M Fe 1.5 M sun R Fe 8000 km R Fe 8000 km Collapse (implosion)

80 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Evolution of Stars 6 8 M sun M ??? 6 8 M sun M ??? All burning cycles Onion skin Onion skin structure with structure with degenerate iron degenerate iron core coreCorecollapsesupernova Neutron star Neutron star (often pulsar) (often pulsar) Sometimes Sometimes black hole? black hole? Supernova Supernova remnant (SNR), remnant (SNR), e.g. crab nebula e.g. crab nebula M 0.08 M sun M 0.08 M sun Never ignites hydrogen cools (hydrogen white dwarf) Brown dwarf Brown dwarf 2 M 5 8 M sun 2 M 5 8 M sun Helium ignition non-degenerate 0.8 M 2 M sun 0.8 M 2 M sun Degenerate helium core after hydrogen exhaustion Carbon-oxygen Carbon-oxygen white dwarf white dwarf Planetary nebula Planetary nebula 0.08 M 0.8 M sun 0.08 M 0.8 M sun Hydrogen burning not completed in Hubble time Low-mass Low-mass main-squence star main-squence star

81 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Evolution of a Low-Mass Star H Main-Sequence MS HorizontalBranch H He HB Ged-Giant Branch H He RGB Asymptotic Giant Branch H He CO AGB

82 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Planetary Nebulae Hour Glass Nebula Hour Glass Nebula Planetary Nebula IC 418 Planetary Nebula IC 418 Planetary Nebula NGC 3132 Planetary Nebula NGC 3132 Eskimo Nebula Eskimo Nebula

83 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Globular Clusters of the Milky Way The galactic globular cluster M3 Globular clusters on top of the FIRAS 2.2 micron map of the Galaxy

84 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Color-magnitude diagram synthesized from several low-metallicity globular Color-magnitude diagram synthesized from several low-metallicity globular clusters and compared with theoretical isochrones (W.Harris, 2000) clusters and compared with theoretical isochrones (W.Harris, 2000) Hot, blue cold, red Color-Magnitude Diagram for Globular Clusters H Main-Sequence Mass Stars with M Stars with M so large that so large that they have burnt they have burnt out in a Hubble out in a Hubble time time No new star No new star formation in formation in globular globular clusters clusters

85 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Color-magnitude diagram synthesized from several low-metallicity globular Color-magnitude diagram synthesized from several low-metallicity globular clusters and compared with theoretical isochrones (W.Harris, 2000) clusters and compared with theoretical isochrones (W.Harris, 2000) Hot, blue cold, red Color-Magnitude Diagram for Globular Clusters H Main-Sequence H He Red Giant H He CO Asymptotic Giant H He Horizontal Branch CO WhiteDwarfs

86 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Basics of Stellar Evolution Bounds on Neutrino Properties Bounds on Neutrino Properties

87 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Basic Argument Flux of weakly interacting particles Flux of weakly interacting particles Star Low-mass weakly-interacting particles can be emitted from stars Low-mass weakly-interacting particles can be emitted from stars New energy-loss channel New energy-loss channel Back-reaction on stellar properties and evolution Back-reaction on stellar properties and evolution What are the emission processes? What are the emission processes? What are the observable consequences? What are the observable consequences?

88 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Bernstein et al.

89 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Color-magnitude diagram synthesized from several low-metallicity globular Color-magnitude diagram synthesized from several low-metallicity globular clusters and compared with theoretical isochrones (W.Harris, 2000) clusters and compared with theoretical isochrones (W.Harris, 2000) Hot, blue cold, red Color-Magnitude Diagram for Globular Clusters H Main-Sequence H He Red Giant H He CO Asymptotic Giant H He Horizontal Branch CO WhiteDwarfs Particle emission reduces Particle emission reduces helium burning lifetime, helium burning lifetime, i.e. number of HB stars i.e. number of HB stars Particle emission delays He ignition, i.e. core mass increased

90 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Neutrinos from Thermal Plasma Processes Photo (Compton) Plasmon decay Pair annihilation Bremsstrahlung Plasmon decay

91 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Plasmon Decay in Neutrinos Propagation in vacuum: Photon massless Photon massless Can not decay into other Can not decay into other particles, even if they particles, even if they themselves are massless themselves are massless Interaction in vacuum: Massless neutrinos do Massless neutrinos do not couple to photons not couple to photons May have dipole moments May have dipole moments or even millicharges or even millicharges Interaction in a medium: Neutrinos interact coherently with Neutrinos interact coherently with the charged particles which the charged particles which themselves couple to photons themselves couple to photons Induces an effective charge Induces an effective charge In a degenerate plasma In a degenerate plasma (electron Fermi energy E F and (electron Fermi energy E F and Fermi momentum p F ) Fermi momentum p F ) Degenerate helium core (and C V = 1) Degenerate helium core (and C V = 1) Propagation in a medium: Photon acquires a refractive index Photon acquires a refractive index In a non-relativistic plasma In a non-relativistic plasma (e.g. Sun, white dwarfs, core of red (e.g. Sun, white dwarfs, core of red giant before helium ignition, …) giant before helium ignition, …) behaves like a massive particle: behaves like a massive particle: Plasma frequency Plasma frequency (electron density n e ) (electron density n e ) Degenerate helium core Degenerate helium core ( = 10 6 g cm 3, T = 8.6 keV) ( = 10 6 g cm 3, T = 8.6 keV) Plasmon decay

92 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Plasmon Decay vs. Cherenkov Effect Refractive index n (k = n ) n < 1 n > 1 Example Ionized plasma Ionized plasma Normal matter for Normal matter for large photon energies large photon energies Water (n 1.3), air, glass for visible frequencies Photon dispersion in a medium can be Time-like 2 k k 2 0Space-like Allowed process in medium that is forbidden in vacuum Plasmon decay to neutrinos Cherenkov effect

93 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Neutrino-Photon-Coupling in a Plasma For vector-current analogous to photon polarization tensor Neutrino effective in-medium coupling Usuallynegligible

94 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Neutral-Current Couplings and Plasmon Decay NeutrinoFermion CVCVCVCV Neutron CACACACA Proton Electron Standard-model Standard-model plasmon decay plasmon decay process process Standard-model Standard-model plasmon decay plasmon decay produces almost produces almost exclusively exclusively A neutral-current process that was never useful for neutrino counting unlike big-bang nucleosynthesis (of course today Z 0 -decay width fixes N = 3) fixes N = 3)

95 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Neutrino Electromagnetic Form Factors Effective coupling of electromagnetic field to a neutral fermion Charge e = F 1 (0) = 0 Anapole moment G 1 (0) Magnetic dipole moment = F 2 (0) Electric dipole moment = G 2 (0) Charge form factor F 1 (q 2 ) and anapole G 1 (q 2 ) are short-range interactions Charge form factor F 1 (q 2 ) and anapole G 1 (q 2 ) are short-range interactions if charge F 1 (0) 0 if charge F 1 (0) 0 Connect states of equal helicity Connect states of equal helicity In the standard model they represent radiative corrections to weak interaction In the standard model they represent radiative corrections to weak interaction Dipole moments connect states of opposite helicity Dipole moments connect states of opposite helicity Violation of individual flavor lepton numbers (neutrino mixing) Violation of individual flavor lepton numbers (neutrino mixing) Magnetic or electric dipole moments can connect different flavors Magnetic or electric dipole moments can connect different flavors or different mass eigenstates (Transition moments) or different mass eigenstates (Transition moments) Usually measured in Bohr magnetons B = e 2m e Usually measured in Bohr magnetons B = e 2m e

96 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Standard Dipole Moments for Massive Neutrinos In standard electroweak model, neutrino dipole and transition moments are induced at higher order Massive neutrinos i (i = 1,2,3), mixed to form weak eigenstates Explicit evaluation for Dirac neutrinos (Magnetic moments ij electric moments ij ) electric moments ij )

97 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Standard Dipole Moments for Massive Neutrinos Diagonal case Diagonal case (Magnetic moments (Magnetic moments of Dirac neutrinos) of Dirac neutrinos) Off-diagonal case Off-diagonal case (Transition moments) (Transition moments) First term in First term in f(m /m W ) does not f(m /m W ) does not contribute contribute (GIM cancellation) (GIM cancellation) Largest neutrino mass eigenstate 0.05 eV < m < 0.2 eV For Dirac neutrino expect

98 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Consequences of Neutrino Dipole Moments Spinprecession in external E or B fields Decay or Cherenkoveffect Plasmon decay in stars Scattering T electron recoil energy

99 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Plasmon Decay and Stellar Energy Loss Rates Assume photon dispersion relation like a massive particle (nonrelativistic plasma) Energy-loss rate of stellar plasma (temperature T and plasma and plasma frequency pl ) frequency pl ) Photon decay rate (transverse plasmon) with energy E with energy E Millicharge Dipole moment Standard model

100 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Globular Cluster Limits on Neutrino Dipole Moments Globular-cluster limit on neutrino dipole moment Compare magnetic-dipole plasma emission with standard case For red-giant core before helium ignition pl = 18 keV Require this to be < 1

101 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Neutrino Radiative Lifetime Limits Plasmondecay Radiativedecay For low-mass neutrinos, plasmon decay in globular cluster stars yields most restrictive limits

102 Georg Raffelt, Max-Planck-Institut für Physik, München, Germany Neutrino Physics & Astrophysics, Sept 2008, Beijing, China Limits on Milli-Charged Particles Davidson, Hannestad & Raffelt JHEP 5 (2000) 3 Globular cluster limit most restrictive for small masses


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