The Potential of Spaced-based High-Energy Neutrino Measurements via the Airshower Cherenkov Signal

Future space-based experiments, such as OWL and JEM-EUSO, view large atmospheric and terrestrial neutrino targets. With energy thresholds slightly above 10^19 eV for observing airshowers via air fluorescence, the potential for observing the cosmogenic neutrino flux associated with the GZK effect is limited. However, the forward Cherenkov signal associated with the airshower can be observed at much lower energies. A simulation was developed to determine the Cherenkov signal strength and spatial extent at low-Earth orbit for upward-moving airshowers. A model of tau neutrino interactions in the Earth was employed to determine the event rate of interactions that yielded a tau lepton which would induce an upward-moving airshower observable by a space-based instrument. The effect of neutrino attenuation by the Earth forces the viewing of the Earth's limb to observe the nu_tau-induced Cherenkov airshower signal at above the OWL Cherenkov energy threshold of ~10^16.5 eV for limb-viewed events. Furthermore, the neutrino attenuation limits the effective terrestrial neutrino target area to ~3x10^5 km^2 at 10^17 eV, for an orbit of 1000 km and an instrumental full Field-of-View of 45 degrees. This translates into an observable cosmogenic neutrino event rate of ~1/year based upon two different models of the cosmogenic neutrino flux, assuming neutrino oscillations and a 10% duty cycle for observation.Comment: Contribution to the 32nd ICRC, Beijing, China, August 2011; Paper#1331, 4 pages, 4 figure

Organic atmospheric particulate material

Carbonaceous compounds comprise a substantial fraction of atmospheric particulate matter (PM). Particulate organic material can be emitted directly into the atmosphere or formed in the atmosphere when the oxidation products of certain volatile organic compounds condense. Such products have lower volatilities than their parent molecules as a result of the fact that adding oxygen and/or nitrogen to organic molecules reduces volatility. Formation of secondary organic PM is often described in terms of a fractional mass yield, which relates how much PM is produced when a certain amount of a parent gaseous organic is oxidized. The theory of secondary organic PM formation is outlined, including the role of water, which is ubiquitous in the atmosphere. Available experimental studies on secondary organic PM formation and molecular products are summarized

Light Quark Masses and Mixing Angles

I review the present state of our knowledge about the masses and weak mixing elements of the u, d, s quarks. This is the written version of lectures given in the 1993 Theoretical Advanced Study Institute (TASI).Comment: UMHEP-402, Latex file, 27 page

New insights concerning dimension-eight effects in weak decays

Most past work on weak nonleptonic decays has mixed dimensional regularization in the weak operator product expansion with some form of a cutoff regularization in the evaluation of the matrix elements. Even with the usual technique of matching the two schemes, this combination misses physics at short distance which can be described by dimension eight (and higher dimension) operators. I describe some recent work with V. Cirigliano and E. Golowich which clarifies these effects and provides a numerical estimate suggesting that they are important.Comment: 3 pages, talk presented at the Division of Particles and Fields Meeting, DPF 2000, Columbus, Ohio, Aug. 200

Vitamins

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The Controversy Concerning Nomenclature Vis-A-Vis Homosexuality

Father Harvey\u27s article contemplates the changes that have and will accrue from the recent AP A decision regarding homosexuals

Morality and institutions: an exploration

This paper explores the question of how culturally varying views of ‘morality’, ‘fairness’ and ‘justice’, particularly those held by the rural poor in developing countries, influence the way people evaluate,work within, use and (sometimes) resist, economic institutions – especially the institutions that emerge or are actively promoted during ‘development’ (market-oriented or otherwise)? It reviews the way this and related questions have been dealt with in a wide range of subjects, including social anthropology, institutional economics, economic sociology, experimental economics, and the study of rural protest. It then discusses how insights about morality and its interactions with institutions could be incorporated more widely into our understanding of the relationship between institutions and development and, in particular, whether we should begin to understand moralities as part of the wider domain of informal institutions which interact with formal institutions to shape behaviours