ISAPP 2011 International on Astroparticle Physics Neutrinos School

ISAPP 2011, International on Astroparticle Physics Neutrinos. School and the Stars 26 th July– 5 th August 2011, Varenna, Italy Neutrinos and the Stars I Stellar Evolution and Neutrinos Georg G. Raffelt Max-Planck-Institut für Physik, München, Germany Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Where do Neutrinos Appear in Nature? Nuclear Reactors Particle Accelerators Earth Atmosphere (Cosmic Rays) Earth Crust (Natural Radioactivity) Sun Supernovae (Stellar Collapse) SN 1987 A Astrophysical Accelerators Soon ? Cosmic Big Bang (Today 330 n/cm 3) Indirect Evidence

Neutrinos from the Sun Helium Reactionchains Energy 26. 7 Me. V Solar radiation: 98 % light 2 % neutrinos At Earth 66 billion neutrinos/cm 2 sec Hans Bethe (1906 -2005, Nobel prize 1967) Thermonuclear reaction chains (1938) Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Bethe’s Classic Paper on Nuclear Reactions in Stars No neutrinos from nuclear reactions in 1938 … Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Predicting Neutrinos from Stars Phys. Rev. 58: 1117 (1940) Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Sun Glasses for Neutrinos? 8. 3 light minutes Several light years of lead needed to shield solar neutrinos Bethe & Peierls 1934: … this evidently means that one will never be able to observe a neutrino. Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

First Detection (1954 – 1956) Clyde Cowan (1919 – 1974) Anti-Electron Neutrinos from Hanford Nuclear Reactor Georg Raffelt, MPI Physics, Munich Fred Reines (1918 – 1998) Nobel prize 1995 n p Detector prototype Cd g g 3 Gammas in coincidence g ISAPP 2011, 2/8/11, Varenna, Italy

First Measurement of Solar Neutrinos Inverse beta decay of chlorine 600 tons of Perchloroethylene Homestake solar neutrino observatory (1967– 2002) Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

2002 Physics Nobel Prize for Neutrino Astronomy Ray Davis Jr. (1914– 2006) Masatoshi Koshiba (*1926) “for pioneering contributions to astrophysics, in particular for the detection of cosmic neutrinos” Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Basics of Stellar Evolution Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Equations of Stellar Structure Assume spherical symmetry and static structure (neglect kinetic energy) Excludes: Rotation, convection, magnetic fields, supernova-dynamics, … Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Virial Theorem and Hydrostatic Equilibrium Hydrostatic equilibrium Integrate both sides Average energy of single “atoms” of the gas Virial Theorem: Most important tool to study self-gravitating systems Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Dark Matter in Galaxy Clusters Velocity dispersion from Doppler shifts and geometric size Coma Cluster Georg Raffelt, MPI Physics, Munich Total Mass ISAPP 2011, 2/8/11, Varenna, Italy

Dark Matter in Galaxy Clusters Fritz Zwicky: Die Rotverschiebung von Extragalaktischen Nebeln (The redshift of extragalactic nebulae) Helv. Phys. Acta 6 (1933) 110 In order to obtain the observed average Doppler effect of 1000 km/s or more, the average density of the Coma cluster would have to be at least 400 times larger than what is found from observations of the luminous matter. Should this be confirmed one would find the surprising result that dark matter is far more abundant than luminous matter. Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Virial Theorem Applied to the Sun Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Nuclear Binding Energy Fe Mass Number Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Hydrogen Burning: Proton-Proton Chains < 0. 420 Me. V 1. 442 Me. V 100% PP-I 0. 862 Me. V 0. 24% 85% 15% 90% 10% hep 0. 02% < 18. 8 Me. V 0. 384 Me. V < 15 Me. V PP-II Georg Raffelt, MPI Physics, Munich PP-III ISAPP 2011, 2/8/11, Varenna, Italy

Hydrogen Burning: CNO Cycle Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Thermonuclear Reactions and Gamow Peak LUNA Collaboration, nucl-ex/9902004 Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Main Nuclear Burnings • Each type of burning occurs at a very different T but a broad range of densities • Never co-exist in the same location Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Hydrogen Exhaustion Main-sequence star Hydrogen Burning Georg Raffelt, MPI Physics, Munich Helium-burning star Helium Burning Hydrogen Burning ISAPP 2011, 2/8/11, Varenna, Italy

Burning Phases of a 15 Solar-Mass Star Lg [104 Lsun] Burning Phase Dominant Process Hydrogen H He Tc rc [ke. V] [g/cm 3] 3 5. 9 Ln/Lg 2. 1 - Duration [years] 1. 2 107 Helium He C, O 14 1. 3 103 6. 0 1. 7 10 -5 1. 3 106 Carbon C Ne, Mg 53 1. 7 105 8. 6 1. 0 Neon Ne O, Mg 110 1. 6 107 9. 6 1. 8 103 7. 0 Oxygen O Si 160 9. 7 107 9. 6 2. 1 104 1. 7 Silicon Si Fe, Ni 270 2. 3 108 9. 6 9. 2 105 6 days Georg Raffelt, MPI Physics, Munich 6. 3 103 ISAPP 2011, 2/8/11, Varenna, Italy

Neutrinos from Thermal Processes Photo (Compton) Plasmon decay Pair annihilation Bremsstrahlung These processes were first discussed in 1961 -63 after V-A theory Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Plasmon Decay in Neutrinos Propagation in vacuum: • Photon massless • Can not decay into other particles, even if they themselves are massless Georg Raffelt, MPI Physics, Munich Plasmon decay Interaction in vacuum: • Massless neutrinos do not couple to photons • May have dipole moments or even “millicharges” ISAPP 2011, 2/8/11, Varenna, Italy

Neutrino-Photon-Coupling in a Plasma For vector current it is analogous to photon polarization tensor Usually negligible Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Plasmon Decay vs. Cherenkov Effect Photon dispersion in a medium can be Refractive index n (k = n w) Example “Time-like” “Space-like” w 2 - k 2 > 0 w 2 - k 2 < 0 n<1 n>1 • Ionized plasma • Normal matter for large photon energies Water (n 1. 3), air, glass for visible frequencies Allowed process that is forbidden in vacuum Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Effective Neutrino Neutral-Current Couplings Neutral current Effective four fermion coupling E ≪ MW, Z Charged current Neutrino Fermion CV CA Electron Proton Neutron Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Existence of Direct Neutrino-Electron Coupling Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Self-Regulated Nuclear Burning Main-Sequence Star Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Modified Stellar Properties by Particle Emission Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Degenerate Stars (“White Dwarfs”) Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Degenerate Stars (“White Dwarfs”) Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Stellar Collapse Onion structure Main-sequence star Degenerate iron core: r 109 g cm-3 T 1010 K Hydrogen MFe 1. 5 MBurning sun RFe 8000 km Georg Raffelt, MPI Physics, Munich Collapse (implosion) Helium-burning star Helium Burning Hydrogen Burning ISAPP 2011, 2/8/11, Varenna, Italy

Normal vs. Giant Stars Main-sequence star 1 M⊙ (Hydrogen burning) Helium-burning star 1 M⊙ Large surface area low temperature “red giant” Large luminosity mass loss Georg Raffelt, MPI Physics, Munich Envelope convective ISAPP 2011, 2/8/11, Varenna, Italy

Red Giant Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Evolution of a Low-Mass Star H H He H CO He MS Main-Sequence Georg Raffelt, MPI Physics, Munich RGB Ged-Giant Branch HB AGB Horizontal Branch Asymptotic Giant Branch ISAPP 2011, 2/8/11, Varenna, Italy

Planetary Nebulae Hour Glass Nebula Planetary Nebula IC 418 Eskimo Nebula Georg Raffelt, MPI Physics, Munich Planetary Nebula NGC 3132 ISAPP 2011, 2/8/11, Varenna, Italy

Evolution of Stars M < 0. 08 Msun Never ignites hydrogen cools (“hydrogen white dwarf”) Brown dwarf 0. 08 < M ≲ 0. 8 Msun Hydrogen burning not completed in Hubble time Low-mass main-squence star 0. 8 ≲ M ≲ 2 Msun Degenerate helium core after hydrogen exhaustion 2 ≲ M ≲ 5 -8 Msun Helium ignition non-degenerate 8 Msun ≲ M < ? ? ? Georg Raffelt, MPI Physics, Munich All burning cycles Onion skin structure with degenerate iron core Core collapse supernova • Carbon-oxygen white dwarf • Planetary nebula • Neutron star (often pulsar) • Sometimes black hole? • Supernova remnant (SNR), e. g. crab nebula ISAPP 2011, 2/8/11, Varenna, Italy

Globular Clusters of the Milky Way Globular clusters on top of the FIRAS 2. 2 micron map of the Galaxy http: //www. dartmouth. edu/~chaboyer/mwgc. html The galactic globular cluster M 3 Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Color-Magnitude Diagram for Globular Clusters • Stars with M so large that they have burnt out in a Hubble time • No new star formation in globular clusters M H as Hot, blue s cold, red Main-Sequence Color-magnitude diagram synthesized from several low-metallicity globular clusters and compared with theoretical isochrones (W. Harris, 2000) Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Color-Magnitude Diagram for Globular Clusters H He H CO He Asymptotic Giant Red Giant H H He CO Horizontal Branch Hot, blue White Dwarfs cold, red Main-Sequence Color-magnitude diagram synthesized from several low-metallicity globular clusters and compared with theoretical isochrones (W. Harris, 2000) Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Basics of Stellar Evolution Bounds on Particle Properties Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Basic Argument: Stars as Bolometers Flux of weakly interacting particles • Low-mass weakly-interacting particles can be emitted from stars • New energy-loss channel • Back-reaction on stellar properties and evolution • What are the emission processes? • What are the observable consequences? Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Electromagnetic Properties of Neutrinos Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Neutrino Electromagnetic Form Factors Effective coupling of electromagnetic field to a neutral fermion Charge en = F 1(0) = 0 Anapole moment G 1(0) Magnetic dipole moment m = F 2(0) Electric dipole moment e = G 2(0) • Charge form factor F 1(q 2) and anapole G 1(q 2) are short-range interactions if charge F 1(0) = 0 • Connect states of equal helicity • In the standard model they represent radiative corrections to weak interaction • Dipole moments connect states of opposite helicity • Violation of individual flavor lepton numbers (neutrino mixing) Magnetic or electric dipole moments can connect different flavors or different mass eigenstates (“Transition moments”) • Usually measured in “Bohr magnetons” m. B = e/2 me Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Consequences of Neutrino Dipole Moments Spin precession in external E or B fields Scattering T electron recoil energy Plasmon decay in stars Decay or Cherenkov effect Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Plasmon Decay and Stellar Energy Loss Rates Assume photon dispersion relation like a massive particle (nonrelativistic plasma) Photon decay rate (transverse plasmon) with energy Eg Millicharge Dipole moment Standard model Energy-loss rate of stellar plasma Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Color-Magnitude Diagram for Globular Clusters H He H Particle emission delays He ignition, i. e. He core mass increased CO Asymptotic Giant Red Giant H H He Particle emission reduces helium burning lifetime, O i. e. number of HBCstars White Dwarfs Horizontal Branch Hot, blue cold, red Main-Sequence Color-magnitude diagram synthesized from several low-metallicity globular clusters and compared with theoretical isochrones (W. Harris, 2000) Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Measurements of Globular Cluster Observables Number ratio of HB vs. RGB stars in 15 globular clusters Georg Raffelt, MPI Physics, Munich Brightness difference between HB (RR Lyrae stars) and brightest red giant in 26 globular clusters ISAPP 2011, 2/8/11, Varenna, Italy

Core-Mass at Helium Ignition Primordial helium (observations & implied by CMBR acoustic peaks) G. Raffelt, Stars as Laboratories for Fundamental Physics (1996) Catelan et al. , astro-ph/9509062 Core mass at helium ignition established to 0. 030 Msun or 6% Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Globular Cluster Limits on Neutrino Dipole Moments Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy

Further Reading on Particle Limits from Stars Georg Raffelt: Stars as Laboratories for Fundamental Physics (University of Chicago Press, 1996) Particle Physics from Stars Annu. Rev. Nucl. Part. Sci. 49 (1999) 163– 216 [hep-ph/9903472] Astrophysical Methods to Constrain Axions and Other Novel Particle Phenomena Phys. Rept. 198 (1990) 1– 113 Georg Raffelt, MPI Physics, Munich ISAPP 2011, 2/8/11, Varenna, Italy