Status of 3-neutrino and 4-neutrino scenarios

Some aspects of the current neutrino oscillation phenomenology are briefly discussed, with emphasis on the status of mass-mixing parameters relevant for scenarios with three active neutrinos, and with an additional fourth sterile neutrino.Comment: 3 pages (including 1 figure). Talk presented at NOW 2000, 2nd International Europhysics Neutrino Oscillation Workshop (Conca Specchiulla, Otranto, Italy), September 9-16, 2000, to be published in Nucl. Phys. B (Proc. Suppl.

Phenomenology of Neutrino Oscillations

We review the status of several phenomenological topics of current interest in neutrino oscillations: (i) Solar neutrino oscillations after the first Sudbury Neutrino Observatory measurements, including both model-independent and model-dependent results; (ii) Dominant nu_mu-->nu_tau oscillations of atmospheric and K2K neutrinos, and possible subdominant oscillations induced by either extra states or extra interactions; and (iii) Four-neutrino scenarios embedding the controversial LSND evidence for oscillations.Comment: 9 pages, including 12 figures. Presented at TAUP 2001: Topics in Astroparticle and Underground Physics, Assergi, Italy, 8-12 Sep. 200

Analysis of oscillations of atmospheric neutrinos

We briefly review the current status of standard oscillations of atmospheric neutrinos in schemes with two, three, and four flavor mixing. It is shown that, although the pure \nu_\mu-->\nu_\tau channel provides an excellent 2\nu fit to the data, one cannot exclude, at present, the occurrence of additional subleading \nu_\mu-->\nu_e oscillations (3\nu schemes) or of sizable \nu_\mu-->\nu_s oscillations (4\nu schemes). It is also shown that the wide dynamical range of energy and pathlength probed by the Super-Kamiokande experiment puts severe constraints on nonstandard explanations of the atmospheric neutrino data, with a few notable exceptions.Comment: Talk at the 19th International Conference on Neutrino Physics and Astrophysics - Neutrino 2000 (Sudbury, Ontario, Canada, 16-21 June 2000

Statistical treatment of detection cross-section uncertainties in the analysis of solar neutrino data

We propose a modification to the standard statistical treatment of the detection cross-section uncertainties in the analysis of solar neutrino data. We argue that the uncertainties of the energy-averaged cross sections of the different neutrino fluxes in the same experiment should be treated as correlated. We show that the resulting allowed regions for the neutrino oscillation parameters are significantly larger than the ones obtained with uncorrelated uncertainties.Comment: 12 pages. Corrected Figures 4 and 5 (vacuum oscillations

A frequentist analysis of solar neutrino data

We calculate with Monte Carlo the goodness of fit and the confidence level of the standard allowed regions for the neutrino oscillation parameters obtained from the fit of solar neutrino data. We show that the values of the goodness of fit and of the confidence level of the allowed regions are significantly smaller than the standard ones. Using Neyman's method, we also calculate exact allowed regions with correct frequentist coverage. We show that the standard allowed region around the global minimum of the least-squares function is a reasonable approximation of the exact one, whereas the size of the other regions is dramatically underestimated in the standard method.Comment: 19 page

Three-flavor solar neutrino oscillations with terrestrial neutrino constraints

We present an updated analysis of the current solar neutrino data in terms of three-flavor oscillations, including the additional constraints coming from terrestrial neutrino oscillation searches at the CHOOZ (reactor), Super-Kamiokande (atmospheric), and KEK-to-Kamioka (accelerator) experiments. The best fit is reached for the subcase of two-family mixing, and the additional admixture with the third neutrino is severely limited. We discuss the relevant features of the globally allowed regions in the oscillation parameter space, as well as their impact on the amplitude of possible CP-violation effects at future accelerator experiments and on the reconstruction accuracy of the mass-mixing oscillation parameters at the KamLAND reactor experiment.Comment: 10 pages + 8 figure

Nature or nurture? learning and female labor force dynamics

In the last century, the evolution of female labor force participation has been S-shaped: It rose slowly at first, then quickly, and has leveled off recently. Central to this dramatic rise has been the entry of women with young children. We argue that this S-shaped dynamic came from generations of women learning about the relative importance of nature (endowed ability) and nurture (time spent child-rearing) in determining children's outcomes. Each generation updates the beliefs of their parents, by observing others' outcomes. When few women participate in the labor force, most outcomes are uninformative about the effect of labor force participation and participation rises slowly. As information accumulates and the effects of labor force participation become less uncertain, more women participate, learning accelerates and labor force participation rises faster. As beliefs converge to the truth, participation flattens out. Learning offers a rational explanation for the differences in employment preferences that have been the focus of a large empirical literature. Survey data, wage data and participation data support our story and distinguish it from alternative explanations.Women - Employment

Fertility: The Role of Culture and Family Experience

This paper attempts to disentangle the direct effects of experience from those of culture in determining fertility. We use the GSS to examine the fertility of women born in the US but from different ethnic backgrounds. We take lagged values of the total fertility rate in the woman's country of ancestry as the cultural proxy and use the woman's number of siblings to capture her direct family experience. We find that both variables are significant determinants of fertility, even after controlling for several individual and family-level characteristics.

The solar neutrino problem after three hundred days of data at SuperKamiokande

We present an updated analysis of the solar neutrino problem in terms of both Mikheyev-Smirnov-Wolfenstein (MSW) and vacuum neutrino oscillations, with the inclusion of the preliminary data collected by the SuperKamiokande experiment during 306.3 days of operation. In particular, the observed energy spectrum of the recoil electrons from 8B neutrino scattering is discussed in detail and is used to constrain the mass-mixing parameter space. It is shown that: 1) the small mixing MSW solution is preferred over the large mixing one; 2) the vacuum oscillation solutions are strongly constrained by the energy spectrum measurement; and 3) the detection of a possible semiannual modulation of the 8B \nu flux due to vacuum oscillations should require at least one more year of operation of SuperKamiokande.Comment: 15 pages (RevTeX) + 8 figures (postscript). Requires epsfig.st

Neutrino Oscillation and CP Violation

We reconsider the meaning of observing CP violation in neutrino oscillation.Comment: Talk given at the NUFACT'00: International Workshop on Muon Storage Ring for a Neutrino Factory, Monterey, California, 22-26 May 2000. Several typographical errors are correcte