Now showing items 444-463 of 863

    • Milliarcsecond-Accurate Astrometry of 34 Southern Hemisphere Radio Sources 

      Fey, Alan L.; Ojha, Roopesh; Quick, Jonathan F. H.; Nicolson, George D.; Lovell, James E. J.; Reynolds, John E.; Ellingsen, Simon P.; McCulloch, Peter M.; Johnston, Kenneth J.; Jauncey, David L.; Tzioumis, Anastasios K. (IOP, 2006-11-01)
      Milliarcsecond-accurate radio positions in the International Celestial Reference Frame for 34 southern hemisphere extragalactic sources are reported. The positions are derived from Mark III/IV very long baseline interferometry ...
    • Millisecond Pulsar Origin of the Galactic Center Excess and Extended Gamma-Ray Emission from Andromeda: A Closer Look 

      Eckner, Christopher; Hou, Xian; Serpico, Pasquale D.; Winter, Miles; Zaharijas, Gabrijela; Martin, Pierrick; Mauro, Mattia Di; Mirabal, Nestor; Petrovic, Jovana; Prodanovic, Tijana; Vandenbroucke, Justin (IOP, 2018-07-25)
      A new measurement of a spatially extended gamma-ray signal from the center of the Andromeda galaxy (M31) has recently been published by the Fermi-LAT collaboration, reporting that the emission broadly resembles the so-called ...
    • Mineral Dust Detection Using Satellite Data 

      Shi, Peichang; Song, Qianqian; Patwardhan, Janita; Zhang, Zhibo; Wang, Jianwu
      Mineral dust, defined as aerosol originating from the soil, can have various harmful effects to the environment and human health. The detection of dust, and particularly incoming dust storms, may help prevent some of these ...
    • Minimal dissipation in processes far from equilibrium 

      Bonanca, Marcus V.S.; Deffner, Sebastian (2018)
      A central goal of thermodynamics is to identify optimal processes during which the least amount of energy is dissipated into the environment. Generally, even for simple systems, such as the parametric harmonic oscillator, ...
    • MINUTE-TIMESCALE >100 MeV γ-RAY VARIABILITY DURING THE GIANT OUTBURST OF QUASAR 3C 279 OBSERVED BY FERMI-LAT IN 2015 JUNE 

      Mirabal, N.; et al. (IOP, 2015-06-15)
      On 2015 June 16, Fermi-LAT observed a giant outburst from the flat spectrum radio quasar 3C 279 with a peak >100 MeV flux of ~3.6 × 10⁻⁵ photons cm⁻² s⁻¹, averaged over orbital period intervals. It is historically the ...
    • Missing Gamma-Rays from kpc-scale AGN Jets: A Test of the IC/CMB Model 

      Meyer, Eileen T.; Georganopoulos, Markos; Sparks, William B.; Godfrey, Leith; Perlman, Eric (2015-02-27)
      The physical origin of the X-ray emission in powerful quasar jets has been a long-standing mystery. Though these jets start out on the sub-pc scale as highly relativistic flows, we do not have any direct measurement of ...
    • Missing peroxy radical sources within a summertime ponderosa pine forest 

      Wolfe, G. M.; Cantrell, C.; Kim, S.; Maudlin III, R. L.; Karl, T.; Harley, P.; Turnipseed, A.; Zheng, W.; Flocke, F.; Apel, E. C.; Hornbrook, R. S.; Hall, S. R.; Ullmann, K.; Henry, S. B.; DiGangi, J. P.; Boyle, E. S.; Kaser, L.; Schnitzhofer, R.; Hansel, A.; Graus, M.; Nakashima, Y.; Kajii, Y.; Guenther, A.; Keutsch, F. N. (Copernicus Publications, 2014-05-13)
      Organic peroxy (RO₂) and hydroperoxy (HO₂) radicals are key intermediates in the photochemical processes that generate ozone, secondary organic aerosol and reactive nitrogen reservoirs throughout the troposphere. In regions ...
    • MIXED LAYER DEPTHS VIA DOPPLER LIDAR DURING LOW-LEVEL JET EVENTS 

      Carroll, Brian; Demoz, Belay; Bonin, Timothy; Delgado, Ruben (EPJ, 2018)
      A low-level jet (LLJ) is a prominent wind speed peak in the lower troposphere. Nocturnal LLJs have been shown to transport and mix atmospheric constituents from the residual layer down to the surface, breaching quiescent ...
    • Modeling and Lidar Study on Ozone Over the Chesapeake Bay During OWLETS-2 

      Yang, Zhifeng; Delgado, Ruben; Demoz, Belay; Sullivan, John; Gronoff, Guillaume; Berkoff, Timothy (EDP Sciences, 2020-07-07)
      This study focuses on the distribution of ozone (O₃) concentration near the Chesapeake Bay, USA (hereafter CB) by integrating observations and model simulations. The motivation of this work is to understand reasons causing ...
    • Modeling Atmosphere-Ocean Radiative Transfer: A PACE Mission Perspective 

      Chowdhary, Jacek; Zhai, Peng-Wang; Boss, Emmanuel; Dierssen, Heidi M.; Frouin, Robert; Ibrahim, Amir; Lee, Zhongping; Remer, Lorraine Ann; Twardowski, Michael; Xu, Feng; Zhang, Xiaodong; Ottaviani, Matteo; Espinosa, William Reed; Ramon, Didier (Frontiers Media S.A, 2019-06-18)
      The research frontiers of radiative transfer (RT) in coupled atmosphere-ocean systems are explored to enable new science and specifically to support the upcoming Plankton, Aerosol, Cloud ocean Ecosystem (PACE) satellite ...
    • Modeling Improvements in the ILRS Reprocessing for ITRF2013 

      Pavlis, E. C.; Luceri, V.; Kuzmicz-Cieslak, M.; König, D.; Bianco, G. (National Aeronautics and Space Administration, 2014-10-27)
    • Modeling Ozone in the Eastern U.S. using a Fuel-Based Mobile Source Emissions Inventory 

      McDonald, Brian C.; McKeen, Stuart A.; Cui, Yu Yan; Ahmadov, Ravan; Kim, Si-Wan; Frost, Gregory J.; Pollack, Ilana B.; Peischl, Jeff; Ryerson, Thomas B.; Holloway, John S.; Graus, Martin; Warneke, Carsten; Gilman, Jessica B.; Gouw, Joost A. de; Kaiser, Jennifer; Keutsch, Frank N.; Hanisco, Thomas F.; Wolfe, Glenn M.; Trainer, Michael (ACS Publications, 2018-06-05)
      Recent studies suggest overestimates in current U.S. emission inventories of nitrogen oxides (NOx = NO + NO₂). Here, we expand a previously developed fuel-based inventory of motor-vehicle emissions (FIVE) to the continental ...
    • Modeling Revisions for Improved Reprocessing for ITRF2020 

      Pavlis, Erricos C.; Kuzmicz-Cieslak, M. (National Aeronautics and Space Administration, 2018-11-05)
    • MODELING X–RAY EMISSION OF A STRAIGHT JET: PKS 0920-397 

      SCHWARTZ, D. A.; MASSARO, F.; SIEMIGINOWSKA, A.; WORRALL, D. M.; BIRKINSHAW, M.; MARSHALL, H.; EVANS, D.; PERLMAN, E.; GELBORD, J. M.; LOVELL, J. E. J.; GODFREY, L.; BICKNELL, G.; OJHA, R.; HARDCASTLE, M.; JESTER, S.; JORSTAD, S.; STAWARZ, L. (World Scientific, 2012-01)
      We summarize a study of PKS 0920-397 using our 42 ks Chandra observation in conjunction with our ATCA 20GHz image, and HST/ACS F814W and F475W images. We investigate the hypothesis that the jet X–ray emission is due to ...
    • Modernizing and expanding the NASA Space Geodesy Network to meet future geodetic requirements 

      Merkowitz, S. M.; Bolotin, S.; Elosegui, P.; Esper, J.; Gipson, J.; Hilliard, L.; Himwich, E.; Hoffman, E.D.; Lakins, D. D.; Lamb, R. C.; Lemoine, F. G.; Long, J. L.; McGarry, J. F.; MacMillan, D. S.; Michael, B. P.; Noll, C.; Pavlis, E. C.; Pearlman, M. R.; Ruszczyk, C.; Shappirio, M. D.; Stowers, D. A. (Springer Nature, 2018-10-06)
      NASA maintains and operates a global network of Very Long Baseline Interferometry (VLBI), Satellite Laser Ranging (SLR), and Global Navigation Satellite System ground stations as part of the NASA Space Geodesy Program. The ...
    • Monitoring global climate change using SLR data from LARES and other geodetic satellitespa 

      Paolozzi, Antonio; Paris, Claudio; Pavlis, Erricos C.; Sindoni, Giampiero; Ciufolini, Ignazio; Vendittozzi, Cristian (SPIE, 2016-04-20)
      The Earth Orientation Parameters (EOP), i.e. the spin axis of the Earth, is influenced by the mass redistribution inside and on the surface of the Earth. On the Earth surface, global ice melting, sea level change and ...
    • Monte Carlo simulations of the LARES space experiment to test General Relativity and fundamental physics 

      Ciufolini, I.; Monge, B Moreno; Paolozzi, A.; Koenig, R.; Sindoni, G.; Michalak, G.; Pavlis, E. C. (IOP, 2013-10-08)
      The LARES (LAser RElativity Satellite) satellite was successfully launched in February 2012. The LARES space experiment is based on the orbital determinations of the laser ranged satellites LARES, LAGEOS (LAser GEOdynamics ...
    • Multi-messenger Observations of a Binary Neutron Star Merger 

      Ojha, Roopesh; Lien, A.; Lee, W. H.; et al. (The American Astronomical Society, 2017-10-16)
      On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi ...
    • Multi-Particle Interferometry Based on Double Entangled States 

      Pittman, Todd B.; Shih, Y. H.; Strekalov, D. V.; Sergienko, A. V.; Rubin, M. H. (NASA, 2013-09)
      A method for producing a 4-photon entangled state based on the use of two independent pair sources is discussed. Of particular interest is that each of the pair sources produces a two-photon state which is simultaneously ...
    • Multi-Photon Entanglement and Quantum Teleportation 

      Shih, Yanhua (U. S. Army Research Office, 1999-07-31)
      The project "Multi-Photon Entanglement and Quantum Teleportation" concerns a series of experimental and theoretical investigations on multi-photon entangled states and the applications, for example, quantum teleportation. ...