1,117 research outputs found
Testing for Multiple Bubbles 2: Limit Theory of Real Time Detectors
Singapore MOE Academic Research Tier 2Published in International Economic Review, https://doi.org/10.1111/iere.12131</p
Testing for Multiple Bubbles 1: Historical Episodes of Exuberance and Collapse in the S&P 500
Published in International Economic Review, https://doi.org/10.1111/iere.12132</p
Limits on the Emission of Gamma Rays from M31 (The Andromeda Galaxy) with HAWC
The detection of the Fermi Bubbles suggests that spiral galaxies such as the
Milky Way can undergo active periods. Using gamma-ray observations, we can
investigate the possibility that such structures are present in other nearby
galaxies. We have analyzed the region around the Andromeda Galaxy (Messier
Catalog M31) for signs of bubble-like emission using TeV gamma-ray data
recorded by the High-Altitude Water Cherenkov Observatory. We fit a model
consisting of two 6 kpc bubbles symmetric about and perpendicular to the M31
galactic plane and assume a power-law distribution for the gamma-ray flux. We
compare the emission from these bubble regions to that expected from structures
similar to the Fermi Bubbles found in the Milky Way. No significant emission
was observed. We report upper limits on the TeV flux from Fermi Bubble
structures in M31.Comment: Presented at the 35th International Cosmic Ray Conference (ICRC2017),
Bexco, Busan, Korea. See arXiv:1708.02572 for all HAWC contribution
Monitoring Cointegrating Polynomial Regressions: Theory and Application to the Environmental Kuznets Curves for Carbon and Sulfur Dioxide Emissions
This paper develops residual-based monitoring procedures for cointegrating polynomial regressions, i.e., regression models including deterministic variables, integrated processes as well as integer powers of integrated processes as regressors. The regressors are allowed to be endogenous and the stationary errors are allowed to be serially correlated. We consider five variants of monitoring statistics and develop the results for three modified least squares estimators for the parameters of the CPRs. The simulations show that using the combination of self-normalization and a moving window leads to the best performance. We use the developed monitoring statistics to assess the structural stability of environmental Kuznets curves (EKCs) for both CO2 and SO2 emissions for twelve industrialized country since the first oil price shock
A Space Communications Study Final Report, Sep. 15, 1965 - Sep. 15, 1966
Reception of frequency modulated signals passed through deterministic and random time-varying channel
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