Cristina VOLPE ( AstroParticule - PowerPoint Presentation

1. Cristina VOLPE(AstroParticule et Cosmologie–APC, Paris) Open issues inneutrino flavor conversion in media

2. Neutrino flavor conversion in media4He, D, 3H, 7Li primordial abundances Early universe -8B nn e Survival ProbabilityNeutrino Energy (MeV)pep7Be nBorexino , PRL 2012MSW solutionpp Core-collapse supernovae solar neutrinosMSW effect :resonant flavor conversion due to n-e interactionImportant for observations in astrophysical and cosmological context :8B n

3. Core-collapse supernovae comprise : O-Ne-Mg supernovae Iron core-collapse supernovae Very massive -> accretion-disk black hole (AD-BH) Two of the key open questions in astrophysics :- How do very massive stars explode ?- What is the site where heavy elements are made ? Core-collapse supernovaeironSiO-Ne-MgH-He

4. The explosionCurrent simulations :multidimensional, realistic neutrino transport, convection and turbulence, hydrodynamical instabilities (SASI).Neutrinos play a role in revitalizing the shock.See MICRA workshop, september 2013, Trento.first 3D : hints for explosion in 3D not enhanced compared to 2DHanke et al, arXiv:1303.6269Bruenn et al, arXiv:1002.4909

5. NucleosynthesisSupernovae, AD-BH, neutron star mergers :sites for heavy elements nucleosynthesis. Neutrinos determine if the site is neutron-rich(r-process elements) or proton-rich (np-process). n flavor conversion in matter impacts the nucleosynthetic outcomes.see Focus Issue on «Nucleosynthesis and Neutrinos» to appear in Journal of Physics G.Beun, McLaughlin, Surman, Hix, PRD73 (2006), 0602012

6. More observations Time and energy signal from a supernova explosion. In our galaxy, 1-3 events/century; one explosion/3years at 3 Mpc.SN1987A eventsSuzuki, J. of Physics, Conf. (2008) Galais, Kneller, Volpe, Gava, PRD 81(2010) , arXiv :0906.5294. The Diffuse Supernova Neutrino Background : The SN fluxes integrated over cosmological redshift.Events (10 y) window detector 90 (IH/NH) 9-25 MeV 50 kton scintillator 300 19-30 MeV 440 kton water Cherenkov 30 17-41 MeV 50 kton liquid argonnenene

7. nentnmNSNeutrino luminosity curvescoolingaccretionTime after bounce (s)Hüdepohl et al. PRL 104 (2010)coolingaccretionfrom simulationsneutronization burstTime and energy signal of different explosion phases important :a sensitive probe of the supernova dynamicsneutrinosphere

8. n flavour conversion in supernovaeshock wavesn-e MSW the n interaction with n and with matter (MSW effect). dynamical aspects - shock waves and turbulence. Flavour conversion effects arise because of nmneneutrinosphere

9. Distance in SNn e Survival Probability n flavour conversion in supernovaePantaleone, PLB 287 (1992), Samuel,PRD 48 (1993)synchronizationbippolarspectral split Collective stable and unstable modes in flavor space Effects of the nn interactioncharacteristicimprints Neutrino Fluxes Neutrino Energy (MeV)at 200 km Duan,Fuller,Qian PRD74 (2006) 76 (2007), Hannestad, al. PRD 74 (2006), Galais, Kneller, Volpe JPG 39 (2012)Duan, Fuller, Qian, PRD76(2007); Meng and Qian, PRD (2011); Raffelt and Smirnov PRD 76, PRL (2007); Esteban-Pretel et al PRD78 (2008) Pehlivan et al, PRD 84 (2011); Galais and Volpe, PRD 84 (2011), Chakraborty, Fischer, Mirizzi, Saviano, Tomas, PRL 107 (2011), Lund and Kneller, PRD 88 (2013), …

10. ? n flavour conversion in supernovaeneutronization burstaccretioncooling(first 50 ms)(50-500 ms)(1-10 s)n-nshock waveEFFECTS MSW Different effects are relevant at different explosion timescales :The final picture could be simpler than we (might) think.Dated 12/11/13

11. Open questions impact on the shock wave impact on (heavy elements) nucleosynthesis, see e.g. Duan, Friedland, McLaughlin, Surman, JPG 38 (2011) merging with realistic supernova simulations (eg. breaking the spherical or azymuthal symmetries)Dasgupta, o’Connor, Ott, PRD 85 (2012)Qian et al, PRL 71 (1993)Further work needed to finally assess :Is the mean-field approximation sufficient ?n trappedn freestreamingnucleosynthesisshock waveBalantekin and Pehlivan, JPG 34 (2007)

12. Looking across fields…Establishing the connection between n flavour conversion in media and other many-body systems such as npgiant resonancesnuclear collisionmetallic clustersphonons76Ge76As76Sebb(0n)double-beta decaycondensed matter

13. e-eeppnnLet us consider a system of N-particles described by a Hamiltonian :nnpppnnnppppeeeeeThe exact evolutionN-body density matrixThe system evolution is determined by solving the Liouville Von-Neumann equation for D :

14. Born-Bogoliubov-Green-Kirkwood-Yvon hierarchyKirkwood 1935, Yvon 1935, Born and Green 1946, Bogoliubov 1946BBGKY : a hierarchy of equations for reduced density matricesSolving exactly the full many-body problem equivalent toone-body densitytwo-body density

15. A novel perspective to n conversionVolpe, Väänänen, Espinoza, PRD87 (2013), arXiv: 1302.2374 We have applied the BBGKY hierarchy to neutrinos and antineutrinospropagating in environments : a rigorous derivation of n evolution equations it allows to test current mean-field approximation UNIFIED APPROACH FOR COSMOLOGICAL and ASTROPHYSICAL applications

16. First BBGKY equation the mean-field approximationone-body densitiestwo-body density two-body correlations The first BBGKY equation reduces to :withMEAN-FIELD re (MSW case) a n and n backgrounds for the early Universe, supernovae, AD-BHThe n evolution equations in presence of a matter background consistent with previous derivations Sigl and Raffelt, Nucl. Phys. B406 (1993), Fuller and Qian PRD 51 (1995)

17. Beyond mean-field The extended mean-field n equations can be cast as Volpe, Väänänen, Espinoza, PRD87 (2013), arXiv: 1302.2374 PAIRING MEAN-FIELD generalised densitygeneralised Hamiltonianthe role of neutrino-antineutrino (and other) correlations?n-n pairing correlationsabnormal density

18. terms GF2 :n trappedterms GFmean-fieldBoltzmannneutrinospherentnmnethe transition region in supernovaenmnetransition region extended descriptionNeutrino equations are non-linear :novel features can arise.Further numerical investigations necessaryfor direction-changing term see also, Cherry et al., PRL108 (2012)

19. Appearance of stable or unstable collectivemodes studied through linearization. Sawyer PRD79 (2009), Banerjee, Dighe, Raffelt, PRD 84 (2011)Distance in SNn e Probabilitysynchronizationbippolar Collective stable and unstable modes

20. flavor space STABILITY MATRIX EIGENVALUES:real (stable) or imaginary (unstable) modesnpgiant resonances76Ge76As76Sebb(0n)double-beta decayDistance in SNn e Probabilitysynchronizationbippolar Collective stable and unstable modeswStability matrixVäänänen, Volpe, PRD88 (2013), arXiv: 1306.6372 General linearized equations using methodsfrom many-body approaches

21. Current SN observatories MiniBOONEHALOBorexinoLVDDaya-BayBaksanSK (104) KamLAND (400)IceCube (106)Different detection channels available : scattering of anti-ne with p, ne with nuclei, nx with e, pLarge scale detectors (LENA, GLACIER, Hyper-K,…) under study

22. COMBINING DIFFERENT DETECTION CHANNELSVäänänen, Volpe, JCAP 1110 (2011) One-neutron eventsTwo-neutron events An example : CC+NC events in HALO-2 (1 kton lead), SN at 10 kpc Pinning down informationWith nn and the n-matter uncertainties in the fluxes, at the neutrinosphere

23. Conclusions and PerspectivesNumerous aspects understood but more work needed.An important question : testing the mean field approximation.Establishing connections to other many body systems offers novel perspectives : BBGKY gives extended equations with neutrino-antineutrino correlations (but also collisions). - general eigenvalue equations and a stability matrix to study stable and unstable modes. Studies combining different detection channels to pin down Interesting information. A lot to learn from future observations

24. Merci

25. n-properties and supernovaeInteresting information on unknown neutrino properties encoded in the supernova neutrino fluxes, in particular the mass hierarchy - earth matter effects (with one or two-detectors) ; - the early time signal ; - the full time and energy signal of the explosion. sterile neutrinos non-standard interactions CP violation – exist but small - Balantekin, Gava, Volpe, PLB662, (2008), arXiv:0710.3112Gava, Volpe, Phys. Rev. D78 (2008), arXiv:0807.3418

26. The first BBGKY equation the mean-field approximationone-body densitytwo-body densitytwo-body correlations The first BBGKY equation reduces to :withMEAN-FIELD

27. derived from first principlesThe n evolution equations in presence of a matter backgroundThe MSW and nn (mean-field) termsoff-diagonalre electron mean-fieldn mean-field a n and n backgrounds for the early Universe, supernovae, AD-BHConsistent with previous derivations Sigl and Raffelt, Nucl. Phys. B406 (1993), Fuller and Qian PRD 51 (1995)