Local variance asymmetries in Planck temperature anisotropy maps

Recently, it was shown that local variance maps of temperature anisotropy are simple and useful tools for the study of large scale hemispherical power asymmetry. This was done by studying the distribution of dipoles of the local variance maps. In this work, we extend the study of the dipolar asymmetry in local variance maps using foreground cleaned Planck 143 GHz and 217 GHz data to smaller scales. In doing so, we include the effect of the CMB Doppler dipole. Further, we show that it is possible to use local variance maps to measure the Doppler dipole in these Planck channel maps, after removing large scale features (up to $l=600$), at a significance of about $3 \sigma$. At these small scales, we do not find any power asymmetry in the direction of the anomalous large scale power asymmetry beyond that expected from cosmic variance. At large scales, we verify previous results i.e. the presence of hemispherical power asymmetry at a significance of at least $3.3 \sigma$.Comment: 7 pages and 7 figures; various typos fixed and discussions clarified in v2 to match the MNRAS accepted versio

Negotiating and Navigating the Rough Terrain of Transnational Feminist Research

This article examines aspects of feminist methodology pertinent to carrying out transnational research within an era of globalization. I explore the use of self-reflexivity, engagement with conceptualizations of insider/outsider, and the employment of feminist critiques of notions of objectivity within the research process as feminist methodological tools relevant to transnational feminist research. I argue that in an age of globalization, such methodological frameworks and tools are necessary in research committed to feminist contestations of globalization in that the nature of transnational research sustains an ever dynamic and shifting landscape of personal, political, and geographical relationships. This article draws upon my experiences carrying out transnational research in Ireland and the United States for my PhD dissertation between 2003 and 200

Thermal Creation of Electron Spin Polarization in n-Type Silicon

Conversion of heat into a spin-current in electron doped silicon can offer a promising path for spin-caloritronics. Here we create an electron spin polarization in the conduction band of n-type silicon by producing a temperature gradient across a ferromagnetic tunnel contact. The substrate heating experiments induce a large spin signal of 95 $\mu$V, corresponding to 0.54 meV spin-splitting in the conduction band of n-type silicon by Seebeck spin tunneling mechanism. The thermal origin of the spin injection has been confirmed by the quadratic scaling of the spin signal with the Joule heating current and linear dependence with the heating power

Effects of flavor-symmetry violation from staggered fermion lattice simulations of graphene

We analyze the effects of flavor splitting from staggered fermion lattice simulations of graphene. Both the unimproved action, and the tadpole improved action with a Naik term show significant flavor symmetry breaking in the spectrum of the Dirac operator. We also measure the average plaquette term and describe how it calls for a reinterpretation of previous lattice Monte Carlo simulation results, due to tadpole improvement. From this we infer that the simulations are indicative of a semi-metal phase for suspended graphene.Comment: 7 pages, 5 figures; v2. added results for noncompact gauge action; v3. added results for stout smearing, corrected rescaling of coupling, published versio