### Neutrinos and Ultra-High Energy Cosmic Rays

### Soft Susy-breaking terms from strings

### Introduction to Ultra-High Energy Cosmic Rays (III)

### Dark Matter Detection in the Light of Recent Experimental Results

### Introduction to Ultra-High Energy Cosmic Rays (II)

### Introduction to Ultra-High Energy Cosmic Rays (I)

### Exploring Neutrino Mixing angles and Dirac and Majorana CP Violation Phases at GUT Scale

$V_{13}\sineq 0$ and (2) $\tan^2 \theta_{\rm atm}\simeq 1$. The

recent SNO data implies that the solar mixing angle is far from the

maximal value, $\tan^2 \theta_{\rm sol}\simeq 0.37$. From these data,

it may be natural to assume that at GUT scale, the mixing angles would

be such that (1) $$V_{13}=0$ and (2) $\tan^2 \theta_{\rm atm}\simeq

1$. Then, we explore what kind of solar mixing angle would be at the

GUT scale. The model $V_{13}=0$ at GUT scale, the number of parameters

in the neutrino mass matrix is three masses, two mixing angles and two

Majorana phases. At $m_Z$ scale, $V_{13}$ as well as a Dirac phase is

induced by the radiative correction. In particular, we found that

$\sin^22\tilde\theta_{12}\leq \sin^22\theta_{\rm sol}$, where

$\theta_{12}$ and $\theta_{\rm sol}$ are mixing angles at the GUT

scale and at $m_Z$ scale resprctively. This means that if the solar

mixing angle at $m_Z$ scale is really far from maximal, $\tan^2

\theta_{\rm sol}\simeq 0.37$, then the Bi-maximal scheme can not be a

realistic model. We also discuss possible sizes of $V_{13}$ and a

Dirac CP violation phase.We also comment on the relation between the

CP violation phase and phases which appear in leptogenesis.

### Supersymmetry in the Next Linear Collider

### Neutrino oscillations in dense neutrino media

refractive index is dominated by the neutrinos themselves. Several

previous studies have found numerically that these self-interactions

have the effect of coupling different neutrino modes in such a way as

to synchronize the flavor oscillations which otherwise would depend on

the energy of a given mode. We show a simple explanation for this

baffling phenomenon in analogy to a system of magnetic dipoles which

are coupled by their self-interactions to form one large magnetic

dipole which then precesses coherently in a weak external magnetic

field (analogous to the weak-field Zeeman effect in atoms).

### Neutrinos in Cosmology

most restrictive limits on the overall neutrino mass scale comes from

cosmological structure formation arguments in conjunction with

large-scale galaxy surveys. Conversely, the cosmic neutrino mass

density can be constrained by laboratory measurements of the neutrino

mass, for example in the KATRIN experiment, if the cosmic number

density of neutrinos were known. However, it depends on the unknown

cosmic neutrino degeneracy parameters. We show that neutrino

oscillations effectively lead to chemical equilibrium before big-bang

nucleosynthesis (BBN) if the favored LMA solution of the solar

neutrino problem applies. It is supported by the recent SNO

results. In this case the restrictive BBN limit on the chemical

potential of the electron neutrino applies to all flavors and the

cosmic neutrino density is tightly constrained to be within 1% of its

standard value. The primordial neutrino oscillations involve

fascinating non-linear effects due to the neutrino self-potential

which lead to a synchronization of the oscillations of different

modes. It is fascinating that solving the solar neutrino problem with

the LMA solution indirectly provides a number count of the cosmic

neutrino sea. We finally also mention leptogenesis as an important

cosmological role for Majorana neutrino masses in the experimentally

favored regime.

### Neutrinos: from experiment to theory

followed by a review of the paradigm of three active neutrinos, and a

discussion of a natural approach to neutrino mass matrices based on

the see-saw mechanism with right-handed neutrino dominance, with some

examples of unified models satisfying these criteria. I also briefly

mention leptogenesis and the idea of a neutrino factory.

### Entropy-Area Relations in Field Theory

scalar field in the background of a curved time-independent metric. To

account for the curvature of space, we postulate a position-dependent

cutoff that depends on energy. With this cutoff, we calculate the

scalar contribution in a background anti-de Sitter space, the exterior

of a black hole, and de Sitter space.In all cases, we find results

that can be simply interpreted in terms of local energy and proper

volume, yielding insight into why a theory appears to be holographic.

### Variations on the seesaw mechanism

seesaw mechanism is used as the basic ingredient. I put emphasis on

large or maximal neutrino mixing and show how such mixing angles can

be achieved either by radiative corrections or by lepton number

symmetries.

### Supersymmetric Sfermion Sector with CP Violating Phases

of 3rd generation scalar fermions. We work in the Minimal

Supersymmetric Standard Model and take the Higgs-higgsino mass

parameter mu and the trilinear scalar coupling parameters A_f

complex. We analyse the dependence on the complex phases of the CP

conserving and CP violating observables.

### CP-Matter Interplay and Measuring MNS in Neutrino Oscillations

remaining parameters in the (1-3) sector of the MNS matrix (lepton

flavor mixing matrix). One of the key point is to understand the

structure of CP-matter interplay. Then I focus on the low-energy

option and discuss the issue of parameter ambiguity and its

resolution.

### Large lepton flavour violating signals in supersymmetric models at future e+e- colliders

collider within the general MSSM, allowing for the most general flavor

structure. We demonstrate that there is a large region in parameter

space with large signals, while being consistent with present

experimental bounds on rare lepton decays such as mu -> e gamma. In

our analysis, we include all possible signals from charged slepton and

sneutrino production and their decays as well as from the decays of

neutralinos and charginos. We also consider the background from the

Standard Model and the MSSM. We find that in general the signature e

tau + missing energy is the most pronounced one.

### A simple connection between neutrino oscillation and leptogenesis

triplets in left-right symmetric theories. The contribution from the

left-handed Higgs triplet to the see-saw formula can dominate over the

conventional one when the neutrino Dirac mass matrix is identified

with the charged lepton or down quark mass matrix. In this case an

analytic calculation of the lepton asymmetry, generated by the decay

of the lightest right-handed Majorana neutrino, is possible. For

typical parameters, the out-of-equilibrium condition for the decay is

automatically fulfilled. The baryon asymmetry has the correct order of

magnitude, as long as the lightest mass eigenstate is not much lighter

then 10^{-6} to 10^{-8} eV, depending on the solution of the solar

neutrino problem. A sizable signal in neutrinoless double beta decay

can be expected, as long as the smallest mass eigenstate is not much

lighter than 10^{-3} eV and the Dirac mass matrix is identified with

the charged lepton mass matrix.

### Introduction to Ultra-High Energy Cosmic Rays (IV)

### Wave Packet Treatment of Neutrino Oscillations

### Ruling out four-neutrino oscillation interpretations of the LSND anomaly?

### Bulk neutrinos and core cooling in Supernovae

with bulk fermions in the context of supernova physics. Following

the usual energy loss argument, the core cooling strongly constraints

the size of such extra dimensions and the mixing parameters. We show

that these constraints can be widely relaxed due to a feedback mechanism

that self-limits the loss. This mechanism also affects the protoneutron

star evolution through a non trivial interplay with neutrino diffusion.

Finally, we discuss the consistency with the SN1987A signal and possible

effects on the neutrino flux composition and the delayed explosion

scenario.

### Confronting spin flavor solutions of the solar neutrino problem with current and future solar neutrino data

### Leptogenesis via hidden sector: unifying the visible and dark matters

provide a natural candidate for dark matter. Phenomenological and astrophysical implications of such a scenario is discussed.

### Leptogenesis from the bottom-up

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See also the IFIC – CSIC/UVEG seminar list

See also the IFIC – CSIC/UVEG seminar list