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Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.

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Showing 1 to 20 of 50 for “"spectral index"”.

  1. Probing diffuse galactic synchrotron emission using meerkat single dish data

    Mahlalela, SifisoUniversity of the Western Cape2025

    … one way to probe said emission is to measure the spectral index of this power law. From the various results available in the literature, the average spectral index for frequencies that are between 0.408 and 3.8 GHz is ∼ −2.7. In this study, the MeerKLASS UHF-data (544-1087 MHz) was used alongside …

    western-cape Repository record

  2. Visualizing muscular fatigue during running exercises with electromyography-derived variables.

    Lewis, Adam David, 1992-Baylor University.2020

    … root mean square amplitude, 2nd order Dimitrov spectral index, and fractal dimension. A validation trial with calf raises proved the reliability of these parameters. Results of the running trials showed that both gastrocnemius muscles had their mean frequency and fractal dimension increase, …

    baylor Repository record

  3. Radio & Infrared Observations of the W3/W4/W5 Star-forming Regions

    Natt, KizThe Open University2015

    … in new parameter space, both spatially and spectrally. A LOFAR calibration pipeline was developed as part of this work (§ 3) resulting in unique continuum maps ~10 deg<sup>2</sup> that detail extended diffuse emission of W3/W4/W5 at unprecedented sensitivity and angular resolution at low …

    the-open-u Repository record

  4. New algorithm for neural network data discrimination applied to Markarian 421 high energy gamma rays

    Macot, Luc1998

    … and is further used for determining the spectral index of the Markarian 421 source.

    concordia Repository record

  5. Accretion and outflow in black-hole x-ray binaries

    Dusoye, AvishekDepartment of Astronomy2015

    … a CP spectrum can be constructed and the spectral index can be estimated. There are 4 ways of producing CP emission and the spectral index helps us to constrain the CP production mechanism. In addition, the kinematics of propelling a proton-electron plasma in a jet is different from that …

    cape-town Repository record

  6. Circumstellar Structure Properties of Young Stellar Objects: Envelopes, Bipolar Outflows, and Disks

    Kwon, WoojinUniversity of Illinois at Urbana-Champaign2010

    … simultaneously, we found that the dust opacity spectral index of Class 0 YSOs is around unity, which implies that dust grains have significantly grown already at the earliest stage. In addition, we discussed the radial dependence of the dust opacity spectral index detected in L1448 IRS 3B and …

    uiuc Repository record

  7. Radio Observations of Discs around Young Stellar Objects

    Parker, RaeesaUniversity of Central Lancashire2017

    … dust in the disc of DG Tau B by looking at its spectral energy distribution (SED). We also analyse the proper motions of DG Tau B and the classical T Tauri star DG Tau A to determine if they are a binary. We fit a modified blackbody to the DG Tau B SED and model the dust using a temperature of …

    cent-lancashire Repository record

  8. Analyse de sensibilité des indices de végétation au-dessus d'un couvert forestier de sapin: Étude comparative à partir des données de simulation entre MODIS-EOS, VEGETATION-SPOT and AVHRR-NOAA

    Asalhi, HayatteUniversity of Ottawa (Canada)2013

    … in making the development on the optimal spectral index to characterize the dynamics of a forest cover of a fir tree independently of the internal (underlying soil, topography, saturation and linearity) and external disturbing factors (BRDF and atmosphere) to covers starting from the data …

    ottawa-retro Repository record

  9. Spectator fields and their imprints on the Cosmic Microwave Background

    Wang, Lingfei, Mazumdar, AnupamLancaster University2016

    … of the CMB, namely the power spectrum Pζ , spectral index ns and its running dns/d ln k, the non-Gaussianities fNL, gNL and τNL, and the lack of isocurvature and polarization modes. Based on these studies, we derive the cosmological predictions for the spectator scenario, revealing its …

    lancaster Repository record

  10. Cosmic microwave background predictions of supernatural inflation

    Buttz, Catalina M. (Catalina Marie)Massachusetts Institute of Technology2004

    … the detailed calculations of the scalar spectral index, ns, demonstrate that the energy scale most favored by Randall et. al on particle physics grounds, is actually the one most tightly constrained by observation.

    mit Repository record

  11. Precision measurement of electron and positron flux in cosmic rays with the AMS-02 Detector

    Chen, Hai, Ph. D. Massachusetts Institute of TechnologyMassachusetts Institute of Technology2016

    … a smooth spectrum with no sharp structure. The spectral index ... above 30 GeV is observed to be ... (energy scale). This provides precise measurement for cosmic ray electrons and positrons and can contribute to probing the origin of cosmic rays, informing the studies of new physics..

    mit Repository record

  12. Exploring the faint source population at 15.7 GHz

    Whittam, Imogen HelenUniversity of Cambridge2014

    … FIRST and WENSS) I have investigated the radio spectral properties of the sources in this sample; all but 30 of the 10C sources are matched to a source in one or more of these surveys. I have found a significant increase in the proportion of flat spectrum sources at flux densities below …

    cambridge Repository record

  13. The faint low-frequency radio universe in continuum: exploitation of the pre-SKA deepest survey

    Ocran, EmmanuelDepartment of Astronomy2020

    … 1.4-GHz and JVLA at 5-GHz), I obtain the median spectral index from 325-MHz to 610-MHz to be −0.80 ± 0.29, 610-MHz to 1.4-GHz to be −0.83 ± 0.31 and 1.4-GHz to 5-GHz to be −1.12 ± 0.15. The main result is that the median spectral index appears to steepen at the highest frequency. With the above …

    cape-town Repository record

  14. The dynamical state of a young stellar cluster

    Sullivan, TimothyMissouri University of Science and Technology

    … Sources are chosen based upon their spectral index to focus on the earlier stages of star formation, in this case, Class I and Flat spectrum objects, and compared with a sample of Class II and III objects from the same embedded cluster. It is found that the radial velocity dispersion …

    must-thes Repository record

  15. The Search For Pulsar Wind Nebulae in the Very High Energy Gamma-ray Regime

    Keogh, Dominic RobertDurham University2010

    … is seen concerning the luminosity or spectral index of the nebulae when observed in the TeV gamma-ray regime due to uncertainties in the measurements available. TeV gamma-ray upper limits are calculated for several nebulae observed in the X-ray regime allowing the strength of their …

    durham Repository record

  16. Supersymmetry, supergravity, and String Theory based inflationary cosmology

    Kraj, Megan C.Massachusetts Institute of Technology2020

    … using observable derived constraints of the spectral index and tensor to scalar ratio.

    mit Repository record

  17. Multiwavelength Studies of Rotating Radio Transients

    Miller, Joshua J.2019

    … show evidence for an additional power-law tail. Spectral indices are calculated for the seven RRATs which were detected at multiple frequencies. These RRATs have a mean spectral index of &lang;alpha SI&rang; = -3.2(7), or &lang;alphaSI ln> = -3.1(1) when using mean flux densities derived from …

    wvu Repository record

  18. Full Mueller imaging: direction dependent corrections in polarimetric radio imaging

    Jagannathan, PreshanthDepartment of Astronomy2018

    … is tied to the magnetic field strength B and the spectral index α (defined such that the flux density S ∝ ν −α ) such that ε ∝ B 1+α .

    cape-town Repository record

  19. Hybrid and multifield inflation

    Sfakianakis, Evangelos IMassachusetts Institute of Technology2014

    … mission, finding excellent agreement for the spectral index and tensor to scalar ratio and promising agreement for the existence of iso-curvature modes.

    mit Repository record

  20. Hard X-ray and radio studies of solar flares

    Bain, Hazel MillerUniversity of Glasgow2010

    … spectroscopy shows a powerlaw spectrum with a spectral index of ~4 and NoRH images reveal radio emission at 17 GHz and 34 GHz co-spatial with the hard X-ray emission, thus supporting the evidence for nonthermal emission in the jet. The second event occurred on the 24th of August 2002 and was …

    glasgow Repository record

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