New Distribution Records for Minnesota Odonata

Several Minnesota state record Odonata, Aeshna subarctica, Ophiogomphus anomalus, Stylogomphus albistylus, Stylurus scudderi, and Coenagrion interrogatum are reported, along with notes on the distribution and habitat of Aeshna sitchensis. New county records for Minnesota Odonata are also reported

On the Interpretation of the NA51 Experiment

We study the $p-n$ Drell-Yan asymmetry, recently measured by the NA51 collaboration, and conclude that the value quoted by their experiment only sets a lower limit on the asymmetry of the proton sea. In particular, we notice that charge symmetry breaking between the proton and the neutron may produce corrections which should be taken into account.Comment: To appear in Phys. Lett.

THE ECONOMICS OF PRIVATE VOLUNTARY ORGANIZATIONS AND COLLECTIVE ACTION IN DEER MANAGEMENT

Game theory and other approaches have been used to characterize problems involving high-exclusion-cost goods which also have the characteristic that marginal cost of an additional user is zero over some range. These analytical tools have made valuable contributions to understanding voluntary organizations and collective action. Resource systems for which composition or scale of the resource is an important factor do not fit neatly into the types of problems which are typically analyzed. The Quality Deer Management Association (QDMA) in Southern Wisconsin is used as an example to illustrate where the existing literature must be modified to take account of particular features of this resource problem. Schelling's multi-person prisoner's dilemma model is modified to incorporate preferences and marginal benefits of deer quality to different types of hunters and to explore issues of resource sustainability. Against the odds, the private QDMA has successfully organized hunters to practice harvesting techniques consistent with improved herd quality.Resource /Energy Economics and Policy,

Quantum field tomography

We introduce the concept of quantum field tomography, the efficient and reliable reconstruction of unknown quantum fields based on data of correlation functions. At the basis of the analysis is the concept of continuous matrix product states, a complete set of variational states grasping states in quantum field theory. We innovate a practical method, making use of and developing tools in estimation theory used in the context of compressed sensing such as Prony methods and matrix pencils, allowing us to faithfully reconstruct quantum field states based on low-order correlation functions. In the absence of a phase reference, we highlight how specific higher order correlation functions can still be predicted. We exemplify the functioning of the approach by reconstructing randomised continuous matrix product states from their correlation data and study the robustness of the reconstruction for different noise models. We also apply the method to data generated by simulations based on continuous matrix product states and using the time-dependent variational principle. The presented approach is expected to open up a new window into experimentally studying continuous quantum systems, such as encountered in experiments with ultra-cold atoms on top of atom chips. By virtue of the analogy with the input-output formalism in quantum optics, it also allows for studying open quantum systems.Comment: 31 pages, 5 figures, minor change

Local Duality and Charge Symmetry Violation in Quark Distributions

We use local quark-hadron duality to calculate the nucleon structure function as seen by neutrino and muon beams. Our result indicates a possible signal of charge symmetry violation at the parton level in the very large x region.Comment: 4 pages, 2 figures. Modified version to appear on PRD. A dicussion on the experimental errors of the form factors was adde

Continuous matrix product state tomography of quantum transport experiments

In recent years, a close connection between the description of open quantum systems, the input-output formalism of quantum optics, and continuous matrix product states in quantum field theory has been established. So far, however, this connection has not been extended to the condensed-matter context. In this work, we substantially develop further and apply a machinery of continuous matrix product states (cMPS) to perform tomography of transport experiments. We first present an extension of the tomographic possibilities of cMPS by showing that reconstruction schemes do not need to be based on low-order correlation functions only, but also on low-order counting probabilities. We show that fermionic quantum transport settings can be formulated within the cMPS framework. This allows us to present a reconstruction scheme based on the measurement of low-order correlation functions that provides access to quantities that are not directly measurable with present technology. Emblematic examples are high-order correlations functions and waiting times distributions (WTD). The latter are of particular interest since they offer insights into short-time scale physics. We demonstrate the functioning of the method with actual data, opening up the way to accessing WTD within the quantum regime.Comment: 11 pages, 4 figure

Heavy-quark axial charges to non-leading order

We combine Witten's renormalization group with the matching conditions of Bernreuther and Wetzel to calculate at next-to-leading order the complete heavy-quark contribution to the neutral-current axial-charge measurable in neutrino-proton elastic scattering. Our results are manifestly renormalization group invariant.Comment: 5 pages, revtex styl

Dynamical symmetry breaking in the sea of the nucleon

We derive the nonanalytic chiral behavior of the flavor asymmetry d̅ -u̅ . Such behavior is a unique characteristic of Goldstone boson loops in chiral theories, including QCD, and establishes the unambiguous role played by the Goldstone boson cloud in the sea of the proton. Generalizing the results to the SU(3) sector, we show that strange chiral loops require that the s-s̅ distribution be nonzero.A. W. Thomas, W. Melnitchouk, and F. M. Steffen