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Effects of New Physics on the Evolution of Massive Stars

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Effects of New Physics on the Evolution of Massive Stars Summary Effects of new physics on the evolution of massive stars Massive stars and physics beyond the standard model: How do intermediate and massive stars respond to new physics? Axions and massive stars. Maurizio Giannotti, (MAYBE) Effects of a non-vanishing neutrino magneticBarry moment University on the evolution of a massive star. In collaboration with: A. Friedland,Conclusions V.Cirigliano, and Los perspectives Alamos National Laboratory M.Wise, Barry University A. Heger, University of Minnesota Miami 2011 December 2011 Neutrino Cooling in Stars Standard Cooling: photons and neutrinos The labels refer to the Photon cooling is relevant in the non-degenerate star core region, below T~5×108K Pair Production Plasmon decay HB RG Bremsstrahlung Photoproduction WhiteDwarf SUN Core Evolution of Massive Stars Neutrino Cooling Photon Cooling From A.Heger, A.Friedland, M.G., V.Cirigliano APJ:696 (2009) Observable evolutionary Phases: Central H- and He-burning Massive stars spend 80% to 90% of their life burning hydrogen in their core (H- burning stage), and almost all the rest of their life burning helium in the core and hydrogen in a shell (He-burning stage). Consequently, these are the only stages that can be observed astronomically. [k]) [K]) eff T Teff Log( Log( Star AgeAge [(MyrMyr]) Simulations for a 8M⊙, solar metallicty, from main sequence to end of He-burning. MESA (Modules for Experiments in Stellar Astrophysics), Paxton et al. ApJ Suppl. 192 3 (2011) [arXiv:1009.1622] Observable evolutionary Phases: H-burning Central H- and He-burning He- H-burning burning Main Sequence HeB phase [k]) [K]) eff T Teff Log( Log( Star AgeAge [(MyrMyr]) Simulations for a 8M⊙, solar metallicty, from main sequence to end of He-burning. MESA (Modules for Experiments in Stellar Astrophysics), Paxton et al. ApJ Suppl. 192 3 (2011) [arXiv:1009.1622] Observable evolutionary Phases: H-burning Central H- and He-burning He- Blue Loop: burning the beginning is set by the H-burning shell time scale the end is set by the He-burning core time scale [e.g., Kippenhahn and Weigert (1994)] Main Sequence Blue Loop [k]) [K]) eff T Teff Log( Log( Star AgeAge [(MyrMyr]) Simulations for a 8M⊙, solar metallicty, from main sequence to end of He-burning. MESA (Modules for Experiments in Stellar Astrophysics), Paxton et al. ApJ Suppl. 192 3 (2011) [arXiv:1009.1622] Observable evolutionary Phases: Central H- and He-burning Simulations of evolution in H-R diagram of stars with solar metallicty, from main sequence to end of He-burning. [MESA] Observable evolutionary Phases: Central H- and He-burning RHeB Most of the star BHeB life-time is spent in one of the three sequences: the Main Sequence (central H- burning), the Red central He- MS Burning sequence, and the Blue central He- Burning sequence Simulations of evolution in H-R diagram of stars with solar metallicty, from main sequence to end of He-burning. [MESA] Observable evolutionary Phases: Central H- and He-burning Color-magnitude diagram for Sextans A. MS and BHeB stars From R. C. Dohm-Palmer and E. D. Skillman, (2002) The x-axis shows the V-I color. Observable evolutionary Phases: Central H- and He-burning The relative number and position in the color magnitude diagram of the red and blue He-burning stars has been subject to deep investigation in the last decade. Currently there is a small discrepancy between predictions and observations: (at high luminosities) B/R is too high, and the blues stars are too blue. From Kristen B. W. McQuinn et. al., Astrophys.J. 740 (2011) Log T[k]=4 Log T[k]=3.7 Observable evolutionary Phases: Central H- and He-burning Any new-physics process that is more efficient during the He-burning phase than during the H-burning phase would change the relative number of MS and HeB stars. From Kristen B. W. McQuinn et. al., Astrophys.J. 740 (2011) Log T[k]=4 Log T[k]=3.7 Observable evolutionary Phases: Central H- and He-burning Any new-physics process that is more efficient in the He-burning core than in the H-burning shell during the He-burning stage would change the relative position and number of RHeB and BHeBa stars. [see, e.g., Kippenhahn and Weigert, Springer-Verlag Berlin Heidelberg New York. (1994)] From Kristen B. W. McQuinn et. al., Astrophys.J. 740 (2011) Log T[k]=4 Log T[k]=3.7 The Axion Axions are hypothetical particles whose existence Peccei and Quinn (1977) is a prediction of the Peccei-Quinn solution of the Weinberg (1978), Wilczek (1978) Strong CP problem. Preskill, Wise and Wilczek (1983) In addition, the axion is a prominent dark matter Abbott and Sikivie (1983) candidate (see P. Sikivie talk) Dine and Fischler (1983) Axions interact with matter and radiation: 1 ~ L i C a g a F F int a 5 4 aγ Here we are interested on in the interactios with photons. −10 −1 The current bound on the axion-photon coupling is ga ≤10 GeV Today, the research in axion is experiencing a revival in terms of new experimental effort for its detection, and new theoretical ideas and models. Experimental Axion Search Among the major experiments that are searching for the axion are the Cern Axion Solar Telescope (CAST) and the Axion Dark Matter eXperiment (ADMX). They are both based on the microwave cavity detection of axions proposed by P. Sikivie (1983). CAST searches for axions from the sun, whereas ADMX searches for CDM axions. HB-bound, Raffelt and Dearborn (1987) Axion-photon vertex The figure on the side is from I. G. Irastorza et al., Latest results and prospects of the CERN Axion Solar Telescope, Journal of Physics: Conference Series 309 (2011) 012001 Primakoff production of Axions in Stars Axions can be produced in the core of a star through Primakoff photon conversion, +(Ze) → a +(Ze), in the field of a nucleus. The production rate is [G. Raffelt, PRD 33, 897 (1986)] a where and HB RG SUN A. Friedland, M.G., M. Wise, in preparation We derived an analytical fitting formula for f(x) which fits better than 3% in the region of interest for us. The relative importance of the Primakoff effect is −10 −1 shown above for ga = 10 GeV (g10 = 1), corresponding to the current bound Primakoff production of Axions in Stars Massive star: He-burning stage H-burning He- burning Core: T≈ 108 K Shell: T≈ 106 K A. Friedland, M.G., M. Wise, in preparation Axions effects on the Blue Loop g10=0 g10=0.5 g10=0.6 g10=0.7 g10=0.8 g10=0.9 −10 −1 With g10 = ga / 10 GeV Simulations of evolution in H-R diagram of a 8M⊙, solar metallicty star from main sequence to end of He-burning. [MESA]. Friedland, M.G., M. Wise, in preparation Axions effects on the Blue Loop Increasing ga causes: g10=0 g10=0.5 Less blue stars g10=0.6 g10=0.7 g10=0.8 g10=0.9 Red-shift −10 −1 With g10 = ga / 10 GeV Simulations of evolution in H-R diagram of a 8M⊙, solar metallicty star from main sequence to end of He-burning. [MESA]. Friedland, M.G., M. Wise, in preparation Axions effects on the Blue Loop Simulations of evolution in H-R diagram of a 8M⊙, solar metallicty star from main sequence to end of He-burning. [MESA]. Friedland, M.G., M. Wise, in preparation Axions effects on the Blue Loop Axions would in general affect the expected B/R and the position of the BHeB sequence. According to our simulations, for a value of ga below the current bound the blue loop disappears almost completely. The effect is stronger for heavier stars. For a star of initial mass about 12M ⊙ (and solar metallicity), the blue loop disappears completely already for g10 = 0.5. The figure shows the simulations of the evolution in the H-R diagram of stars (solar metallicty) from main sequence to end of He-burning. [MESA]. Friedland, M.G., M. Wise, in preparation Experimental Evidence for Blue Sequences High metallicity Galaxy V-I Color Figures from Kristen B. W. McQuinn et. al., Astrophys.J. 740 (2011) Experimental Evidence for Blue Sequences High mass (young cluster) High metallicity Galaxy Low mass V-I Color Figures from Kristen B. W. McQuinn et. al., (old cluster) Astrophys.J. 740 (2011) Experimental Evidence for Blue Sequences High metallicity Galaxy uncertainty V-I Color Figures from Kristen B. W. McQuinn et. al., Astrophys.J. 740 (2011) Experimental Evidence for Blue Sequences Result: A value of g10 above 0.8 (optimistically, 0.5) seems to be incompatible with the current observations of HeB sequences. uncertainty V-I Color Kristen B. W. McQuinn et. al., Astrophys.J. 740 (2011) Experimental Evidence for Blue Sequences Result: A value of g10 above 0.8 (optimistically, 0.5) seems to be incompatible with the current observations of HeB sequences. HB-bound, Raffelt and Dearborn (1987) I. G. Irastorza et al., Journal of Physics: uncertainty Conference Series 309 (2011) 012001 V-I Color Kristen B. W. McQuinn et. al., Astrophys.J. 740 (2011) Experimental Evidence for Blue Sequences Result: A value of g10 above 0.8 (optimistically, 0.5) seems to be incompatible with the current observations of HeB sequences. Open questions: - Can the axion explain the small red-shift of the bluest point of the blue loop in the high luminosity region of the CMD? - Can the axion explain the discrepancy in the number of blue and red stars observed experimentally, namely the fact hat B/R is larger than expected? V-I Color Kristen B.
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