15,356 research outputs found
Neutrino masses and R-parity violation
We review different contributions to the neutrino masses in the context of
R-parity violating supersymmetry in a basis independent manner. We comment on
the generic spectrum expected in such a scenario comparing different
contributions.Comment: Invited brief review for Mod. Phys. Lett. A, 15 pages, uses
axodraw.st
The Demand for Cocaine by Young Adults: A Rational Addiction Approach
This paper applies the rational addiction model, which emphasizes the interdependency of past, current, and future consumption of an addictive good, to the demand for cocaine by young adults in the Monitoring the Future Panel. The price of cocaine is added to this survey from the System to Retrieve Information from Drug Evidence (STRIDE) maintained by the Drug Enforcement Administration of the U.S. Department of Justice. Results suggest that annual participation and frequency of use given participation are negatively related to the price of cocaine. In addition current participation is positively related to past and future participation, and current frequency of use given participation is positively related to past and future frequency of use. The long-run price elasticity of total consumption (participation multiplied by frequency given participation) of -1.18 is substantial. A permanent 10 percent reduction in price due, for example, to the legalization of cocaine would cause the number of cocaine users to grow by slightly more than 8 percent and would increase the frequency of use among users by a little more than 3 percent. Surely, both proponents and opponents of drug legalization should take account of this increase in consumption in debating their respective positions.
Electron collision quenching of CO(v) chemiluminescence in CS2/O2 and CS2/O2/N2O flames
Chemiluminescence from vibrationally excited carbon monoxide formed by the reaction CS+O-->CO(v)+S was observed in CS2/O2 and CS2/O2/N2O flames to which an electric discharge was applied. Although the total amount of chemiluminescence increased with increasing discharge current probably due to enhanced reaction rates as a result of radical formation, the vibrational distribution was quenched, becoming thermal in character. The thermalization is attributed to superelastic electron collisions [e+CO(v)-->e+CO(v−1)]. The technique demonstrates a sensitive method for detecting collisional transfers between excited states by separating the perturbation (electron collisions) from the initial excitation mechanism (chemical reactions)
Testing minimal lepton flavor violation with extra vector-like leptons at the LHC
Models of minimal lepton flavor violation where the seesaw scale is higher
than the relevant flavor scale predict that all lepton flavor violation is
proportional to the charged lepton Yukawa matrix. If extra vector-like leptons
are within the reach of the LHC, it will be possible to test the resulting
predictions in ATLAS/CMS.Comment: 19 pages, 8 figure
Leptonic Flavor and CP Violation
We discuss how neutrino oscillation experiments can probe new sources of
leptonic flavor and CP violation.Comment: 8 pages, latex, no figures. Invited talk given at KAON 2001, Pisa,
Italy, June 12 - 17, 200
Assessment of Connections Between Knowledge- Based Economy Characteristics and Selected Macroeconomic Categories in the European Union's Countries by Means of Panel Models
The aim of the article is to analyze the impact of knowledge-based economy variables on the selected macroeconomic categories - the share of total investments in GDP and the employment rate- in European Union's countries in the years 2000-2007, conducted with application of panel models.Celem artykułu jest analiza wpływu zmiennych opisujących gospodarkę opartą na wiedzy na podstawowe kategorie makroekonomiczne - udział całkowitych inwestycji w PKB i stopę zatrudnienia - w krajach Unii Europejskiej (z podziałem na kraje UE-15 i nowe kraje członkowskie UE) w latach 2000-2007, przeprowadzona w oparciu o modele panelowe
Constraining the CKM Parameters using CP Violation in semi-leptonic B Decays
We discuss the usefulness of the CP violating semi-leptonic asymmetry a_{SL}
not only as a signal of new physics, but also as a tool in constraining the CKM
parameters. We show that this technique could yield useful results in the first
years of running at the B factories. We present the analysis graphically in
terms of M_{12}, the dispersive part of the B-Bbar mixing amplitude. This is
complementary to the usual unitarity triangle representation and often allows a
cleaner interpretation of the data.Comment: 15 pages REVTEX, 7 figure
Organization of Multinational Activities and Ownership Structure
We develop a model in which multinational investors decide about the modes of organization, the locations of production, and the markets to be served. Foreign investments are driven by market-seeking and cost-reducing motives. We further assume that investors face costs of control that vary among sectors and increase in distance. The results show that (i) production intensive sectors are more likely to operate a foreign business independent of the investment motive, (ii) that distance may have a non-monotonous effect on the likelihood of horizontal investments, and (iii) that globalization, if understood as reducing distance, leads to more integration
Insulator-to-Metal Transition in Selenium-Hyperdoped Silicon: Observation and Origin
Hyperdoping has emerged as a promising method for designing semiconductors
with unique optical and electronic properties, although such properties
currently lack a clear microscopic explanation. Combining computational and
experimental evidence, we probe the origin of sub-band gap optical absorption
and metallicity in Se-hyperdoped Si. We show that sub-band gap absorption
arises from direct defect-to-conduction band transitions rather than free
carrier absorption. Density functional theory predicts the Se-induced
insulator-to-metal transition arises from merging of defect and conduction
bands, at a concentration in excellent agreement with experiment. Quantum Monte
Carlo calculations confirm the critical concentration, demonstrate that
correlation is important to describing the transition accurately, and suggest
that it is a classic impurity-driven Mott transition.Comment: 5 pages, 3 figures (PRL formatted
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