Neutrinos reliques de supernovae et leurs proprits n

Neutrinos (reliques) de supernovae et leurs propriétés n Cristina VOLPE (Institut de Physique Nucléaire Orsay, FRANCE)

Cosmologie Astrophysique BBN, LSS, leptogènese, … n soleil, SNII, UHEn, Physique du neutrino Physique nucléaire processus double-beta, interaction n-noyau, … UN DOMAINE AUX NOMBREUSES INTERFACES

I. Neutrinos de supernovae : présent et futur PLAN II. Neutrinos de supernovae et physique des neutrinos Conclusions et Pespectives

I. THE first OBSERVATION of SOLAR ne n Homestake mine (South Dakota) 600 tons of C 2 Cl 4 37 Ar + ene + 37 Cl From fusion reactions, like p+p ® 2 H+e++ne « We observe much less neutrinos than we expect. » 1970 the detector « THE SOLAR NEUTRINO PUZZLE » THE IMPORTANT DISCOVERY OF NEUTRINO OSCI

THE OSCILLATION PARAMETERS L n 3 nm nt q 23 n 1 q 12 n 2 ne q 13 The two basis are related by a unitary matrix, called the Maki-Nakagawa-Sakata. Pontecorvo (MNSP) matrix, which is the analog of the Cabibbo-Kobayashi. Maskawa (CKM) matrix for quarks. ne nm nt n 1 q 23 q 13 n 2 q 12 n 3 THE d CP violating PHASE INTRODUCES A n-n

Type II SUPERNOVAE… collapse ne burst E V E N T S cooling Totani et al. , Astr. . J. 1998 0. 1 1. t (s) S N 1 9 8 7 A 10 R. Davis and M. Koshiba , 2002 Nobel Prize with R. Giacconi NEUTRINOS FOLLOW CL THE EXPLOSION MECHA

Neutrinos mass hierarchy ? the mixing angle q 13 ? Majorana or Dirac ? the magnetic moment ? … Type II Supernovae neutrino propagation in the star luminosities, spectra, time distribution of the emitted neutrinos nucleosynthesis (r-process) … Neutrino Astronomy The philosophy… « To use stars and the Universe for the study of fundamental properties. »

FUTURE EXPERIMENTS I. To measure the neutrino II. luminosity curve from a future III. (extra)galactic explosion. EVENTS SK MEMPHYS 9000 140000 II. To measure the relic neutrino background from past supernova explosions. Theoretical predictions close to the present experimental limit (1. 2 anti-ne/cm 2/s from Super-Kamiokande). New observatories of large (megaton) size are under study (water Cherenkov, scintillator, liquid argon technologies are considered). A demand for a design study (LAGUNA) submitted within FP 7. Such observatories can observe far explosion (much more frequent) and reach the sensitivity to observe relic neutrinos. IMPORTANT DISCOVERY FOR SUPERNOVA AND NEUT

Can we use supernova neutrinos to learn about CP violation in the lepton sector ? Thèse de Jérome Gava The possible existence of CP violation in the lepton sector is a crucial issue that will be addressed by « third generation » n experiments (super-beams, beta-beams, neutrino factories).

CP VIOLATION AND SUPERNOVA n A. B. Balantekin, J. Gava, C. Volpe, ar. Xiv: 0710. 3112 Analytically, we have demonstrated that : - if the nm and nt fluxes are equal at emission, there is no CP effect on the (anti)-ne fluxes. - if the nm and nt fluxes differ at emission (ex. physics beyond the Standard Model), there are significant effects from the d phase on the (anti)-ne fluxes. effects in an observatory? Numerically, we have solved the evolution with a non-zero phase : fne (d=180 o) fne(d=0 o) fnm (d=180 o) fnm(d=0 o) SIGNIFICANT CP EFFECTS.

RELIC SUPERNOVA n Relic neutrino fluxes bring information about the explosion, the supernova formation rate and neutrino properties. C. Volpe, J. Welzel, ar. Xiv: 0711. 3237 We have performed a detailed analysis of the three technologies considered for future observatories and proposed to measure both electron neutrinos and anti-neutrinos. ne reactor background ne + p n + e+ hierarchy q 13 relic ne flux ne atmospheric background EVENTS 19. 3 - 27 Me. V 12 - 50 Me. V MEMPHYS 142 – 248 ne 12 - 19 ne INFORMATION ON THE MASS HIERARCHY AND THE

A remark Supernova ne detection exploits neutrino scattering on nuclei: LENA (scintillator), GLACIER (liquid argon), MEMPHYS (water Cherenkov) 12 C 40 Ar 16 O A BETTER KNOWLEDGE OF NEUTRINONUCLEUS REQUIRED. Low energy Beta-beams C. Volpe, J Phys G 30 (2004). 6 He n boost 6 He A new facility to produce pure and intense low energy neutrino beams (10 -100 Me. V, i. e. g = 5 -14). New development for the EURISOL project, included in the FP 6 Design Study (2005 -2009) n

Conclusions et Perspectives L’astronomie neutrino apporte des informations cruciales dans l’étude des particules et des interactions fondamentales. Les neutrinos provenant d’une explosion future ou reliques pourraient etre observés dans les observatoires de prochaine génération (étude de faisabilité dans FP 7).

Conclusions et Perspectives CP VIOLATION (Thèse de Jérome Gava) Un premier travail a montré des effets importants. Diverses études sont à réaliser: - effets dans un observatoire - inclusion de l’interaction neutrino-neutrino. Des études récentes ont montré que cette interaction modifie de façon profonde la propagation des neutrinos dans les supernovae (effet Mikheyev. Smirnov-Wolfenstein ou MSW étudié depuis les années 80).

Conclusions et Perspectives Neutrinos reliques de supernovae On a étudié les potentialités quant à l’observation des neutrinos et des anti-neutrinos reliques dans les observatoires futurs. Des études théoriques poussées nécessaires pour affirmer les potentialités de découverte.

Merci!

Effet Mikheyev-Smirnov-Wolfenstein (MSW) ne e B = -Dm 2/4 En sin 2 q A = -Dm 2/4 En cos 2 q W ne GF re. A potential is introduced due to the coupling with matter. n fluxes Earth at emission 2 n =n m 2 e detection n 2 n 1 =nm n 1 e V(r) vacuum high r coeur core 10