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Statistics on internal migration are important for keeping estimates of subnational population numbers up-to-date as well as urban planning, infrastructure development and impact assessment, among other applications. However, migration flow statistics typically remain constrained by the logistics of infrequent censuses or surveys. The penetration rate of mobile phones is now high across the globe with rapid recent increases in ownership in low-income countries. Analysing the changing spatiotemporal distribution of mobile phone users through anonymized call detail records (CDRs) offers the possibility to measure migration at multiple temporal and spatial scales. Based on a dataset of 72 billion anonymized CDRs in Namibia from October 2010 to April 2014, we explore how internal migration estimates can be derived and modelled from CDRs at subnational and annual scales, and how precision and accuracy of these estimates compare to census-derived migration statistics. We also demonstrate the use of CDRs to assess how migration patterns change over time, with a finer temporal resolution compared to censuses. Moreover, we show how gravity-type spatial interaction models built using CDRs can accurately capture migration flows. Results highlight that estimates of migration flows made using mobile phone data is a promising avenue for complementing more traditional national migration statistics and obtaining more timely and local data.

We study the possibility to perform neutrino oscillation tomography and to determine the neutrino mass hierarchy in kilometer-scale ice Čerenkov detectors by means of the θ 13 -driven matter effects which occur during the propagation of atmospheric neutrinos deep through the Earth. We consider the ongoing IceCube/DeepCore neutrino observatory and future planned extensions, such as the PINGU detector, which has a lower energy threshold. Our simulations include the impact of marginalization over the neutrino oscillation parameters and a fully correlated systematic uncertainty on the total number of events. For the current best-fit value of the mixing angle θ 13 , the DeepCore detector, due to its relatively high-energy threshold, could only be sensitive to fluctuations on the normalization of the Earth's density of ∆ρ ±10% at ∼ 1.6σ CL after 10 years in the case of a true normal hierarchy. For the two PINGU configurations we consider, overall density fluctuations of ∆ρ ±3% (±2%) could be measured at the 2σ CL after 10 years, also in the case of a normal mass hierarchy. We also compare the prospects to determine the neutrino mass hierarchy in these three configurations and find that this could be achieved at the 5σ CL, for both hierarchies, after 5 years in DeepCore and about 1 year in PINGU. This clearly shows the importance of lowering the energy threshold below 10 GeV so that detectors are fully sensitive to the resonant matter effects.

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The low energy neutrino factory has been proposed as a very sensitive setup for future searches for CP violation and matter effects. Here we study how its performance is affected when the experimental specifications of the setup are varied. Most notably, we have considered the addition of the 'platinum' νµ → νe channel. We find that, whilst theoretically the extra channel provides very useful complementary information and helps to lift degeneracies, its practical usefulness is lost when considering realistic background levels. Conversely, an increase in statistics in the 'golden' νe → νµ channel and, to some extent, an improvement in the energy resolution, lead to an important increase in the performance of the facility, given the rich energy dependence of the 'golden' channel at these energies. We show that a low energy neutrino factory with a baseline of 1300 km, muon energy of 4.5 GeV, and either a 20 kton totally active scintillating detector or 100 kton liquid argon detector, can have outstanding sensitivity to the neutrino oscillation parameters θ13, δ and the mass hierarchy. For our estimated exposure of 2.8 × 10 23 kton × decays per muon polarity, the low energy neutrino factory has sensitivity to θ13 and δ for sin 2 (2θ13) > 10 −4 and to the mass hierarchy for sin 2 (2θ13) > 10 −3 .

The Daya Bay and RENO experiments have recently observed a non-zero θ 13 at more than 5σ CL. This has important consequences for future neutrino oscillation experiments. We analyze these within the LAGUNA design study which considers seven possible locations for a European neutrino observatory for proton decay, neutrino, and astroparticle physics. The megaton-scale detector would be an ideal target for a CERN-based neutrino beam with baselines ranging from 130 km to 2300 km. We perform a detailed study to assess the physics reach of the three detector options -a 440 kton water Čerenkov, a 100 kton liquid argon and a 50 kton liquid scintillator detector -at each of the possible locations, taking into account the recent measurement of θ 13 . We study the impact of the beam properties and detector performances on the sensitivity to CPviolation and the mass hierarchy. We find that a liquid argon or water Čerenkov detector can make a 3σ discovery of CP violation for 60% − 70% of the parameter space for any of the baselines under consideration, although the results for the liquid argon detector placed at 130 km are slightly worse and only 40% − 50% is achieved in this case. The performance of the liquid scintillator detector is affected by its level of neutral-current background at all baselines. A 3σ determination of the mass hierarchy is possible for all values of δ, for the values of θ 13 favoured at 3σ by Daya Bay and RENO, for almost all setups with L 650 km.

We explore the physics reach of several possible configurations for a Super-Beam experiment in Europe, focusing on the possibilities of discovering θ13, CP violation in the leptonic sector and the ordering of neutrino mass eigenstates. We consider the three different detector technologies: WaterČerenkov, Liquid Argon and Liquid Scintillator, and seven possible sites in Europe which would be able to host such a detector underground. The distances to these sites from CERN, where the beam would be originated, go from 130 km to 2300 km. The neutrino flux is optimized in each case as to match the first oscillation peak for each of the baselines under consideration. We also study the impact of several experimental factors in the performance of each detector technology. These include the influence of the spectral information, the rejection efficiencies for the neutral-current backgrounds, the ratio between running times in neutrino and antineutrino modes and the systematic uncertainties on the signal and backgrounds, among others. Contribution to NUFACT 11, XIIIth International Workshop on Neutrino Factories, Super beams and Beta beams, 1-6 August 2011, CERN and University of Geneva (Submitted to IOP conference series).

Recent developments on tau detection technologies and the construction of high intensity neutrino beams open the possibility of a high precision search for non-standard µτ flavour transition with neutrinos at short distances. The MINSIS -Main Injector Non-Standard Interaction Search-is a proposal under discussion to realize such precision measurement. This document contains the proceedings of the workshop which took place on 10-11 December 2009 in Madrid to discuss both the physics reach as well as the experimental requirements for this proposal 1 . 1 The original slides can be found at the workshop web-site [1] Contents I. Overview of talks A. MINSIS -Main Injector Non-Standard Interaction Search -A. Para B. ν τ detection: the CHORUS and OPERA experiences -P. Migliozzi C. NSI for Fermilab to DUSEL -S. Parke D. Non-unitarity PMNS matrix (Theory) -S. Antusch E. Non-unitarity PMNS matrix (Bound) -M. Blennow F. Non-standard neutrino Interactions (Theory) -E. Fernández-Martínez G. Non-standard neutrino Interactions (Bound) -T. Ota H. Minimal Flavour violation at MINSIS -R. Alonso I. NSI bounds from ICECUBE -O. Mena J. Probing the Seesaw Scale -from nano to mega electron-volts -A. de Gouvêa K. Sterile neutrino mixings and near detectors -O. Yasuda L. Sterile neutrinos in the MINSIS experiment -T. Li and J. López-Pavón M. New physics searches with near detectors at a neutrino factory -W. Winter N. Very short baseline electron neutrino disappearance -M. Laveder O. Tau detection using the kinematic and impact parameter techniques -F. J. P. Soler