Optical activity of neutrinos and antineutrinos

Using the one-loop helicity amplitudes for low-energy $\nu\gamma\to\nu\gamma$ and $\bar\nu\gamma\to\bar\nu\gamma$ scattering in the standard model with massless neutrinos, we study the optical activity of a sea of neutrinos and antineutrinos. In particular, we estimate the values of the index of refraction and rotary power of this medium in the absence of dispersion.Comment: Additional reference

Identification and Validation of a New Source of Low Grain Cadmium Accumulation in Durum Wheat (Triticum Turgidum L. Subsp. Durum (Defs.))

Cadmium (Cd) is a toxic heavy metal with no known biological function. The maximum level of Cd concentration allowed in the international market for wheat grain is 0.2 mg kg-1. Higher Cd levels in durum wheat (Triticum turgidum L. var. durum Desf) may threaten its export. To develop new durum wheat cultivars low in Cd uptake and speed up the selection process in breeding programs, this study attempted to identify SNP(s) associated with a low Cd uptake in the durum experimental line D041735. D041735 was developed from a cross between hexaploid (Sumai 3) and durum wheat by NDSU breeding program and has consistently shown low grain Cd levels. Therefore, this study sought 1) to identify SNP marker(s) tightly linked to Cd uptake and genetic dissection of the grain Cd content in a recombinant inbred line mapping population derived from D041735 and Divide (a high Cd accumulator cultivar) using wheat 90k SNP chips and 2) to test for alleles from detected Cd-linked markers among three sources of low Cd accumulators, including Strongfield, Haurani, and D041735. The QTL analysis performed in this study identified only a single major QTL for Cd uptake on chromosome arm 5BL. The QTL was detected in a 0.3 cM interval flanked by SNP markers RAC875_c20785_1219 and Kukri_c66357_357. Validation results using these flanking markers initially suggested the existence of a different gene or allele for low Cd uptake in the D041735 line as a new source for the durum breeding program at NDSU. The BLAST analysis of these flanking markers suggested the Aluminum Induced Protein Like Protein and heavy metal transporter ATPase 3 as candidate genes for the major QTL. Allelism testing revealed that the identified QTL in this study is novel and not the previously mapped QTL Cdu1on 5BL. This study therefore confirmed that the D041735 experimental line is a novel source of low Cd uptake in durum wheat germplasms, where the major QTL is most likely introduced from hexaploid wheat

Neutrino-photon reactions for energies above mem_e

We show that neutrino-photon reactions above $m_e$ are dominated by the reaction $\nu \gamma \to \nu e^+ e^-$. We calculate its cross-section and see that it is larger by several orders of magnitude than the cross-sections of other neutrino-photon processes, for energies above $m_e$. We also discuss potential astrophysical and cosmological consequences.Comment: 7 pages, 2 figure

A Framework for Urban Building Energy Use Modeling

Reliable quantification of energy consumption by buildings plays a key role in development of sustainable cities. However, there are methodological uncertainties embedded in the most common urban scale energy use modeling methods and tools which affect the reliability of these tools and their applicability for decision-making purposes. This article presents a novel bottom- up data-driven framework for urban energy use modeling (UEUM) to help predict energy use more precisely through utilizing disaggregated data at building level, incorporating the actual urban spatial patterns, and testing different algorithms to propose an enhanced prediction model. This framework integrates the influential factors in the model including building characteristics; i.e., height, as an urban intensity metric, urban attributes; i.e., sprawl indices, that are captured in a multidimensional way representing compactness and connectivity of neighborhoods, and occupant characteristics. A case study on 800,000 buildings in seventy-seven neighborhoods in Chicago was used to test the framework. This framework has the potential to help better understand the existing urban energy use profiles and provides a more holistic image of urban energy use at multi-scales of building, block, neighborhood, and urban levels

Photons, neutrinos and optical activity

We compute the one-loop helicity amplitudes for low-energy $\nu\gamma\to\nu\gamma$ scattering and its crossed channels in the standard model with massless neutrinos. In the center of mass, with $\sqrt{s} = 2\omega\ll 2m_e$, the cross sections for these $2\to 2$ channels grow roughly as $\omega^6$. The scattered photons in the elastic channel are circularly polarized and the net value of the polarization is non-zero. We also present a discussion of the optical activity of a sea of neutrinos and estimate the values of its index of refraction and rotary power.Comment: 9 pages, ReVTeX4, 6 figures include

Radiative Higgs Boson Decays H -> f fbar gamma

Higgs boson radiative decays of the form $H\rightarrow f\bar{f}\gamma$ are calculated in the Standard Model using the complete one-loop expressions for the decay amplitudes. Contributions to the radiative width from leptons and light quarks are given. We also present $e\bar{e}$ invariant mass distributions for $H\rightarrow e\bar{e}\gamma$, which illustrate the importance of the photon pole contribution and the effects of the box diagrams.Comment: 17 pages, RevTeX, 6 postscript figures include