Welcome to the UA Campus Repository, a service of the University of Arizona Libraries. The repository shares, archives and preserves unique digital materials from faculty, staff, students and affiliated contributors.
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- The UA Libraries is celebrating International GIS Day on November 14th with a morning workshop and afternoon talks. Learn more at http://libguides.library.arizona.edu/GIS/gisday2018
- The Critical Librarianship & Pedagogy Symposium (CLAPS) is happening November 15-16th at The University of Arizona. Proceedings from the 2016 symposium are available in the repository.
- Presentations from October 31st's research data program are now available:
- Celebrate Open Access Week with these University of Arizona events:
- The Arizona Geological Survey (AZGS) Document Repository is now available in the UA Campus Repository. UA Libraries personnel collaborated with AZGS to add historical and current publications to the repository, for immediate public availability and long-term preservation. Content includes geologic maps, reports, bulletins, and other publications.
- More than 200 honors theses from Spring 2018 graduates are now available in the repository. Theses represent research activities from multiple disciplines across campus.
- Tree-Ring Research Volumes 68, 69 and 70 (2012-2014) are now available in the repository.
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Search for Higgs boson decays into pairs of light (pseudo)scalar particles in the gamma gamma jj final state in pp collisions at root s=13 TeV with the ATLAS detector(ELSEVIER SCIENCE BV, 2018-07-10)This Letter presents a search for exotic decays of the Higgs boson to a pair of new (pseudo) scalar particles, H -> aa, where the a particle has a mass in the range 20-60 GeV, and where one of the a bosons decays into a pair of photons and the other to a pair of gluons. The search is performed in event samples enhanced in vector-boson fusion Higgs boson production by requiring two jets with large invariant mass in addition to the Higgs boson candidate decay products. The analysis is based on the full dataset of pp collisions at root s = 13 TeV recorded in 2015 and 2016 with the ATLAS detector at the CERN Large Hadron Collider, corresponding to an integrated luminosity of 36.7 fb(-1). The data are in agreement with the Standard Model predictions and an upper limit at the 95% confidence level is placed on the production cross section times the branching ratio for the decay H -> aa -> gamma gamma gg. This limit ranges from 3.1 pb to 9.0 pb depending on the mass of the a boson. (C) 2018 The Author. Published by Elsevier B.V.
Topologically Protected Helical States in Minimally Twisted Bilayer Graphene(AMER PHYSICAL SOC, 2018-07-17)In minimally twisted bilayer graphene, a moire pattern consisting of AB and BA stacking regions separated by domain walls forms. These domain walls are predicted to support counterpropogating topologically protected helical (TPH) edge states when the AB and BA regions are gapped. We fabricate designer moire crystals with wavelengths longer than 50 nm and demonstrate the emergence of TPH states on the domain wall network by scanning tunneling spectroscopy measurements. We observe a double-line profile of the TPH states on the domain walls, only occurring when the AB and BA regions are gapped. Our results demonstrate a practical and flexible method for TPH state network construction.
Density split statistics: Cosmological constraints from counts and lensing in cells in DES Y1 and SDSS data(AMER PHYSICAL SOC, 2018-07-13)We derive cosmological constraints from the probability distribution function (PDF) of evolved large-scale matter density fluctuations. We do this by splitting lines of sight by density based on their count of tracer galaxies, and by measuring both gravitational shear around and counts-in-cells in overdense and underdense lines of sight, in Dark Energy Survey (DES) First Year and Sloan Digital Sky Survey (SDSS) data. Our analysis uses a perturbation theory model [O. Friedrich et al., Phys. Rev. D 98, 023508 (2018)] and is validated using N-body simulation realizations and log-normal mocks. It allows us to constrain cosmology, bias and stochasticity of galaxies with respect to matter density and, in addition, the skewness of the matter density field. From a Bayesian model comparison, we find that the data weakly prefer a connection of galaxies and matter that is stochastic beyond Poisson fluctuations on <= 20 arcmin angular smoothing scale. The two stochasticity models we fit yield DES constraints on the matter density Omega(m) = 0.26(-0.04)(+0.05) and Omega(m) = 0.28(-0.03)(+0.04) that are consistent with each other. These values also agree with the DES analysis of galaxy and shear two-point functions (3x2pt, DES Collaboration et al.) that only uses second moments of the PDF. Constraints on s 8 are model dependent (sigma(8) = 0.97(-0.06)(+0.07) and 0.80(-0.07)(+0.06) for the two stochasticity models), but consistent with each other and with the 3 x 2pt results if stochasticity is at the low end of the posterior range. As an additional test of gravity, counts and lensing in cells allow to compare the skewness S-3 of the matter density PDF to its Lambda CDM prediction. We find no evidence of excess skewness in any model or data set, with better than 25 per cent relative precision in the skewness estimate from DES alone.
Density split statistics: Joint model of counts and lensing in cells(AMER PHYSICAL SOC, 2018-07-13)We present density split statistics, a framework that studies lensing and counts-in-cells as a function of foreground galaxy density, thereby providing a large-scale measurement of both 2-point and 3-point statistics. Our method extends our earlier work on trough lensing and is summarized as follows: given a foreground (low redshift) population of galaxies, we divide the sky into subareas of equal size but distinct galaxy density. We then measure lensing around uniformly spaced points separately in each of these subareas, as well as counts-in-cells statistics (CiC). The lensing signals trace the matter density contrast around regions of fixed galaxy density. Through the CiC measurements this can be related to the density profile around regions of fixed matter density. Together, these measurements constitute a powerful probe of cosmology, the skewness of the density field and the connection of galaxies and matter. In this paper we show how to model both the density split lensing signal and CiC from basic ingredients: a non-linear power spectrum, clustering hierarchy coefficients from perturbation theory and a parametric model for galaxy bias and shot-noise. Using N-body simulations, we demonstrate that this model is sufficiently accurate for a cosmological analysis on year 1 data from the Dark Energy Survey.
High-order encoding schemes for floodlight quantum key distribution(AMER PHYSICAL SOC, 2018-07-23)Floodlight quantum key distribution (FL-QKD) has realized a 1.3 Gbit/s secret-key rate (SKR) over a 10-dB-loss channel against a frequency-domain collective attack [Quantum Sci. Technol 3, 025007 (2018)]. It achieved this remarkable SKR by means of binary phase-shift keying (BPSK) of multiple optical modes. Moreover, it did so with available technology, and without space-division or wavelength-division multiplexing. In this paper we explore whether replacing FL-QKD's BPSK modulation with a high-order encoding can further increase that protocol's SKR. First, we show that going to K-ary phase-shift keying with K = 32 doublesfrom 2.0 to 4.5 Gbit/sthe theoretical prediction from [Phys. Rev. A 94, 012322 (2016)] for FL-QKD's BPSK SKR on a 50-km-long fiber link. Second, we show that 2d x 2d quadrature amplitude modulation does not offer any SKR improvement beyond what its d = 1 casewhich is equivalent to quadrature phase-shift keyingprovides.