410 likes | 581 Views
Parametric Resonance by the Matter Effect. SATO, Joe (Saitama). Plan Introduction Two-Flavor Oscillation Parametric Resonance in Neutrino Oscillation More on Parametric Resonance Summary. with. Koike, Masafumi (Saitama) Ota, Toshihiko (Würzburg) Saito, Masako (Saitama). Introduction.
E N D
Parametric Resonanceby the Matter Effect • SATO, Joe (Saitama) • Plan • Introduction • Two-Flavor Oscillation • Parametric Resonance in Neutrino Oscillation • More on Parametric Resonance • Summary with Koike, Masafumi (Saitama) Ota, Toshihiko (Würzburg) Saito, Masako (Saitama)
Interior of the Earth http://www.math.montana.edu/~nmp/materials/ess/geosphere/expert/activities/planet_earth/
Interior of the Earth Preliminary Reference Earth Model outer core mantle inner core crust Depth http://www.math.montana.edu/~nmp/materials/ess/geosphere/expert/activities/planet_earth/
Inhomogeneous Matter Koike,Sato 1999 Ota,Sato 2001
Parametric Resonance in Neutrino Oscillation • Ermilova et al. (1986) • Akhmedov, Akhmedov et al. (1988 — Present) • others “Castle-wall” matter profile (Akhmedov, 1998) Fourier decomposition (Present approach) Mode 1 Mode 2 Mode 3
Two-Flavor Oscillation • Evolution equation of the two-flavor neutrino • Matter effect • Second-order equation in dimensionless variables • Dimensionless variables • Initial conditions ,
Constant-Density Oscillation • Peaks and dips of the oscillation spectrum • Simple solution when : • Appearance probability at the endpoint of the baseline • MSW-resonance peak. • (n+1)-th oscillation peak. • n-th oscillation dip.
Constant-Density Oscillation Appearance Prob id numbers of the oscillation peaks Neutrino Energy / [GeV]
Mathieu Equation Evolution Equation • Inhomogeneity • Fourier expansion • Effect of the n-th Fourier mode on the oscillation
Mathieu Equation Pow! Pow! Parametric Resonance in classical mechanics Periodic Motion Oscillation of Oscillation Parameter We kick a swing twice in a period of motion.
Pow! Pow! Parametric Resonance in classical mechanics Periodic Motion Parametric Resonance Condition Parametric Resonance Oscillation of Oscillation Parameter We kick a swing twice in a period of motion.
Parametric Resonance in neutrino oscillation Neutrino Oscillation Fourier modes of matter effect
Parametric Resonance in neutrino oscillation Neutrino Oscillation Parametric Resonance Condition n-th oscillation dip Parametric Resonance Fourier modes of matter effect
Effect of the Mode 1 Sizable effect at 1st peak (n=0) and 2nd peak (n=1) Appearance Prob Neutrino Energy / [GeV]
Earth models suggest for a through-Earth path Mode 1: Possible Large Effect
Earth models suggest for a through-Earth path Mode 1: Possible Large Effect
Effect of the Mode 2 Sizable at 2nd (n=1) and 3rd (n=2) peaks Appearance Prob Neutrino Energy / [GeV]
Effect of the Mode 3 Sizable at 3rd (n=2) and 4th (n=3) peaks Appearance Prob Neutrino Energy / [GeV]
Resonant Enhancement Resonant enhancement of apparance probability, even for a small Fourier coefficient Matter profile (Arbitrary vertical scale) n = 1 Oscillation “dip” at n = 2 Fictious repetition of the matter profile n = 3
Summary • Neutrino oscillation across the Earth • Deviation from the constant density • Fourier analysis • Parametric resonance • Frequency matching of the matter distribution and the neutrino energy • Mathieu-like equation provides an analytic description