Corrections to Tribimaximal Mixing from Nondegenerate Phases

We propose a seesaw scenario that possible corrections to the tribimaximal pattern of lepton mixing are due to the small phase splitting of the right-handed neutrino mass matrix. we show that the small deviations can be expressed analytically in terms of two splitting parameters($\delta_1$ and $\delta_2$) in the leading order. The solar mixing angle $\theta_{12}$ favors a relatively smaller value compared to zero order value ($35.3^\circ$), and the Dirac type CP phase $\delta$ chooses a nearly maximal one. The two Majorana type CP phases $\rho$ and $\sigma$ turn out to be a nearly linear dependence. Also a normal hierarchy neutrino mass spectrum is favored due to the stability of perturbation calculations.Comment: 19 pages 6 figures, Accepted by Mod. Phy. Lett.

Neutrino Factories: Physics Potential

The physics potential of low-performance and high-performance neutrino factories is briefly reviewed..Comment: Talk presented at NUFACT02, London, 1-6 July, 2002. 8 pages, 5 figure

Left-Right Asymmetry of Weak Interaction Mass of Polarized Fermions in Flight

The left-right polarization-dependent asymmetry of the weak interaction mass is investigated. Based on the Standard Model, the calculation shows that the weak interaction mass of left-handed polarized fermions is always greater than that of right-handed polarized fermions in flight with the same velocity in any inertial frame. The asymmetry of the weak interaction mass might be very important to the investigation of neutrino mass and would have an important significance for understanding the parity nonconservation in weak interactions.Comment: 8 pages, 2 figures, corrected calculatio

Hydrophobicity properties of graphite and reduced graphene oxide of the polysulfone (PSf) mixed matrix membrane

Hydrophobicity properties of graphite and reduced graphene oxide (rGO) (from exfoliated graphite/rGO) towards PSf polymer membrane characteristic and properties at different additives weight concentrations (1, 2, 3, 4 and 5 wt. %) were investigated. Both PSF/graphite and PSf/rGO membranes were characterized in term of hydrophobicity, surface bonding, surface roughness and porosity. FTIR peaks revealed that membrane with graphite and reduced graphene oxide nearly diminished their O-H bonding which was opposite to the graphene oxide peak that shows a strong O-H bonding as increased exfoliated times. These results were in line with the contact angle results that showed strong hydrophobicity of graphite and reduced graphene oxide membranes as increased these additives concentration. The effect of strong hydrophobicity in these membranes also has resulted in smoother surface roughness compared to pristine PSf membrane. Further investigation of the performance of water flux also proved that both above membranes have strong hydrophobic effect, with the lowest pure water flux rate (L/m2h) was given by PSf/rGO 3% membrane at 19.2437 L/m2h

Thermodynamics of interacting entropy-corrected holographic dark energy in a non-flat FRW universe

A so-called "entropy-corrected holographic dark energy" (ECHDE), was recently proposed to explain the dark energy-dominated universe with the help of quantum corrections to the entropy-area relation in the setup of loop quantum cosmology. Using this new definition, we investigate its thermodynamical features including entropy and energy conservation. We describe the thermodynamical interpretation of the interaction between ECHDE and dark matter in a non-flat universe. We obtain a relation between the interaction term of the dark components and thermal fluctuation. Our study further generalizes the earlier works [M.R. Setare and E.C. Vagenas, Phys. Lett. B 666 (2008) 111; B. Wang et al., Phys. Lett. B 662 (2008) 1] in this direction.Comment: 14 pages, no figure, accepted by Int. J. Mod. Phys.

Leptogenesis via multiscalar coherent evolution with supersymmetric neutrino see-saw

A novel scenario of leptogenesis is investigated in the supersymmetric neutrino see-saw model. The right-handed sneutrino ${\tilde N}$ and the $\phi$ field in the ${\tilde L} H_u$ direction of the slepton and Higgs doublets start together coherent evolution after the inflation with right-handed neutrino mass $M_N$ smaller than the Hubble parameter of inflation. Then, after some period the motion of ${\tilde N}$ and $\phi$ is drastically changed by the cross coupling $M_N h_\nu {\tilde N}^* \phi \phi$ from the $M_N N N$ and $h_\nu N L H_u$ terms, and the significant asymmetries of ${\tilde N}$ and ${\tilde L}$ are generated. The ${\tilde L}$ asymmetry is fixed later by the thermal effect as the lepton number asymmetry for baryogenesis, while the ${\tilde N}$ asymmetry disappears through the decays ${\tilde N} \to {\bar L} {\bar{\tilde H}}_u, {\tilde L} H_u$ with almost the same rate but opposite final lepton numbers.Comment: 4pages, 1 figure; submitted to Physical Review D. The renormalization group effects were include

A question of hierarchy: matter effects with atmospheric neutrinos and anti-neutrinos

It is by now established that neutrinos mix, have (different) non-zero masses, and therefore oscillate. The oscillation parameters themselves, however, are not all well-known. An open problem is that of the neutrino mass hierarchy. We study the possibility of determining the neutrino mass hierarchy with atmospheric neutrinos using an iron calorimeter detector capable of charge identification such as the proposed MONOLITH and ICAL/INO detectors. We find that such detectors are sensitive to the sign of the mass-squared difference, \delta_{32} = m_3^2 - m_2^2, provided the as-yet unknown mixing angle between the first and third generations, \theta_{13}, is greater than 6 degrees (\sin^2 2\theta_{13} > 0.04). A result with a significance greater than 90% CL requires large exposures (more than 500 kton-years) as well as good energy and angular resolution of the detected muons (better than 15%), especially for small \theta_{13}. Hence obtaining definitive results with such a detector is difficult, unless \theta_{13} turns out to be large. In contrast, such detectors can establish a clear oscillation pattern in atmospheric neutrinos in about 150 kton-years, therefore determining the absolute value of \delta_{32} and \sin^2 2 \theta_{23} to within 10%.Comment: 36 pages revtex with 14 eps figures; new section on statistical significance when detector resolution is include

Peningkatan Kemampuan Pemecahan Masalah Matematis Siswa dengan Menggunakan Model Pembelajaran Creative Problem Solving pada Materi Spldv di Kelas VIII SMP Negeri 2 Takengon

Kemampuan pemecahan masalah merupakan salah satu tujuan atau kompetensi yang akan dicapai dalam pelajaran matematika. Semua pemecahan masalah melibatkan beberapa informasi dan untuk mendapatkan penyelesaiannya digunakan informasi tersebut. Informasi-informasi ini pada umumnya merupakan konsep-konsep atau prinsip-prinsip dalam matematika salah satunya pada sistem persamaan linear dua variabel. karena akan  memudahkan siswa untuk menghitung barang belanjaan di pasar dan juga memudahkan siswa nantinya apabila akan membuat sebuah Perusahan. Selain siswa kurang bisa dalam menyelesaikan soal sistem pesamaan linear dua variabel siswa juga masih kurang terampil dalam menjawab soal pemecahan masalah. Untuk itu peneliti menggukan model pembelajaran Creative Problem Solving (CPS) dalam pemecahan masalah matematis siswa. Penelitian   ini   bertujuan   untuk   mengetahui peningkatan dan perbedaan hasil belajar menggunakan model Creative Problem Solving (CPS) pada siswa kelas VIII SMP Negeri 2 Takengon. Penelitian ini menggunakan pendekatan kuantitatif dengan jenis penelitiannya yaitu quasi ekperimen, karena penelitian ini ingin mengetahui perbedaan dari kelas eksperimen dan kontrol serta ingin melihat peningkatan pada kelas eksperimen yang diberi perlakuan model pembelajaran (CPS). Penelitian yaitu dengan nilai rata-rata pada kelas yang kontrol yaitu 42,9 dan nilai rata-rata pada kelas eksperimen yaitu 53,4, yang dimana kelas tersebut berdistribusi normal. Dengan nilai uji hipotesis thitung ttabel  dimana 12,53  2,02 dengan demikian Ha diterima, sehingga terdapat perbedaan rerata kemampuan pemecahan masalah siswa. Dan hasil pengujian gain ternormalisasi diperoleh untuk kriteria gain ternormalisasi terendah 4 siswa (20%) dan dengan kriteria sedang diperoleh 16 siswa (80%), Sehingga dapat disimpulkan terdapat peningkatan kemampuan masalah siswa pada kelas VIII SMP Negeri  2 Takengon dengan model pembelajaran Creative Problem Solving (CPS)

Neutrino oscillation and expected event rate of supernova neutrinos in adiabatic explosion model

We study how the influence of the shock wave appears in neutrino oscillations and the neutrino spectrum using density profile of adiabatic explosion model of a core-collapse supernova which is calculated in an implicit Lagrangian code for general relativistic spherical hydrodynamics. We calculate expected event rates of neutrino detection at SK and SNO for various theta_{13} values and both normal and inverted hierarchies. The predicted event rates of bar{nu}_e and nu_e depend on the mixing angle theta_{13} for the inverted and normal hierarchies, respectively, and the influence of the shock appears for about 2 - 8 s when sin^2 2 theta_{13} is larger than 10^{-3}. These neutrino signals for the shock propagation is decreased by < 30 % for bar{nu}_e in inverted (SK) or by < 15 % for nu_e in normal hierarchy (SNO) compared with the case without shock. The obtained ratio of the total event for high-energy neutrinos (20 MeV < E_{nu} < 60 MeV) to low-energy neutrinos (5 MeV < E_{nu} < 20 MeV) is consistent with the previous studies in schematic semi-analytic or other hydrodynamic models of the shock propagation. The time dependence of the calculated ratio of the event rates of high-energy to low-energy neutrinos is a very useful observable which is sensitive to theta_{13} and hierarchies. Namely, time-dependent ratio shows clearer signal of the shock propagation that exhibits remarkable decrease by at most factor \sim 2 for bar{nu}_e in inverted (SK), whereas it exhibits smaller change by \sim 10 % for nu_e in normal hierarchy (SNO). Observing time-dependent high-energy to low-energy ratio of the neutrino events thus would provide a piece of very useful information to constrain theta_{13} and mass hierarchy, and eventually help understanding the propagation how the shock wave propagates inside the star.Comment: 19 pages, 9 figures, accepted for publication in Physical Review

Neutrino oscillation probabilities: Sensitivity to parameters

We study in detail the sensitivity of neutrino oscillation probabilities to the fundamental neutrino parameters and their possible determination through experiments. The first part of the paper is devoted to the broad theme of isolating regions in the neutrino (and anti-neutrino) energy and propagation length that are sensitive to the oscillation parameters. Such a study is relevant to neutrinos both from the Earth's atmosphere or from a neutrino factory. For completeness we discuss the sensitivity, however small, to the parameters involved in a three-generation framework, and to the Earth matter density profile. We then study processes relevant to atmospheric neutrinos which are sensitive to and allow precision measurements of the mixing angle theta_23 and mass-squared difference delta_32 apart from the mixing angle theta_13. Crucial to this analysis is charge identification; detectors having this capability can isolate these matter effects. In particular, we address the issue of using matter effects to determine whether the mixing angle theta_23 is maximal, and, if not, to explore how well its octant can be determined. When realistic detector resolutions are included, we find that deviations of about 15% (20%) from a maximal value of sin^2 theta_23=1/2 can be measured at 95% (99%) CL provided theta_13 is non-zero, sin^2 theta_13 >= 0.015, and the neutrino mass ordering is normal, with fairly large exposures of 1000 kton-years.Comment: 37 pages Latex file, 30 eps figure files; minor typos fixe