Now showing items 464-483 of 841

    • Nanofiber-segment ring resonator 

      Jones, D.E.; Hickman, G. T.; Franson, J.D.; Pittman, T.B. (OSA Publishing, 2016)
      We describe a fiber ring resonator comprised of a relatively long loop of standard single-mode fiber with a short nanofiber segment. The evanescent mode of the nanofiber segment allows the cavity-enhanced field to interact ...
    • The NASA Carbon Airborne Flux Experiment (CARAFE): instrumentation and methodology 

      Wolfe, Glenn M.; Kawa, S. Randy; Hanisco, Thomas F.; Hannun, Reem A.; Newman, Paul A.; Swanson, Andrew; Bailey, Steve; Barrick, John; Thornhill, K. Lee; Diskin, Glenn; DiGangi, Josh; Nowak, John B.; Sorenson, Carl; Bland, Geoffrey; Yungel, James K.; Swenson, Craig A. (Copernicus Publications, 2018-03-28)
      The exchange of trace gases between the Earth's surface and atmosphere strongly influences atmospheric composition. Airborne eddy covariance can quantify surface fluxes at local to regional scales (1–1000 km), potentially ...
    • NASA’s Next Generation Space Geodesy Network Typical Core Site Requirements and Layout 

      Esper, J.; Long, J. L.; Lemoine, F. G.; McCormick, D. R.; Merkowitz, S. M.; Ma, C.; McGarry, J. F.; Hilliard, L.; Pavlis, E. C.; Pearlman, M. R.; Stowers, D. A.; Wetzel, S. L. (NASA, 2014-10-14)
      NASA’s renewed commitment to the deployment of a new network of “core” space geodetic sites requires careful planning and consideration for location selection, instrument and facility layout, and required infrastructure. ...
    • NASA’s Next Generation Space Geodesy Project 

      NASA Goddard Space Flight Center Jet Propulsion Laboratory (NASA, 2011-12-16)
      This proposal describes NASA’s Space Geodesy Project. This two-year project will contribute to the Global Geodetic Core Network by: (1) Completing ongoing Network Design Studies that describe the appropriate number and ...
    • The nature of the X-ray flash of August 24 2005 

      Sollerman, J.; Fynbo, J. P. U.; Gorosabe, J.; Halpern, J. P.; Hjorth, J.; Jakobsson, P.; Mirabal, N.; Watson, D.; Xu, D.; Castro-Tirado, A. J.; Féron, C.; Jaunsen, A. O.; Jelínek, M.; Jensen, B. L.; Kann, D. A.; Ovaldsen, J. E.; Pozanenko, A.; Stritzinger, M.; Thöne, C. C.; Postigo, A. de Ugarte; Guziy, S.; Ibrahimov, M.; Järvinen, S. P.; Levan, A.; Rumyantsev, V.; Tanvir, N. (EDP sciences, 2007-04-24)
      Aims. Our aim is to investigate the nature of the X-Ray Flash (XRF) of August 24, 2005. Methods. We present comprehensive photometric R-band observations of the fading optical afterglow of XRF 050824, from 11 minutes to ...
    • Near-infrared and gamma-ray monitoring of TANAMI gamma-ray bright sources 

      Nesci, R.; Tosti, G.; Pursimo, T.; Ojha, R.; Kadler, M. (EDP sciences, 2013-06-18)
      Context. Spectral energy distribution and its variability are basic tools for understanding the physical processes operating in active galactic nuclei (AGN). Aims. In this paper we report the results of a one-year ...
    • Negative entropy production rates in Drude-Sommerfeld metals 

      Bonança, Marcus V. S.; Nazé, Pierre; Deffner, Sebastian (2020-09-30)
      It is a commonly accepted creed that in typical situations the rate of entropy production is non-negative. We show that this assertion is not entirely correct if a time-dependent, external perturbation is not compensated ...
    • Net radiative effects of dust in the tropical North Atlantic based on integrated satellite observations and in situ measurements 

      Song, Qianqian; Zhang, Zhibo; Yu, Hongbin; Kato, Seiji; Yang, Ping; Colarco, Peter; Remer, Lorraine A.; Ryder, Claire L. (Copernicus Publications, 2018-08-13)
      In this study, we integrate recent in situ measurements with satellite retrievals of dust physical and radiative properties to quantify dust direct radiative effects on shortwave (SW) and longwave (LW) radiation (denoted ...
    • A Neutron Star Identification for the High-Energy Gamma-Ray Source 3EG J1835+5918 Detected in the ROSAT All-Sky Survey 

      Mirabal, N.; Halpern, J. P. (IOP, 2001-01-24)
      In the error box of 3EG J1835+5918, the brightest as-yet unidentified EGRET source at intermediate Galactic latitude, we find a weak, ultrasoft X-ray source at energies E < 0.3 keV in the ROSAT All-Sky Survey. Deep optical ...
    • A new airborne laser-induced fluorescence instrument for in situ detection of formaldehyde throughout the troposphere and lower stratosphere 

      Cazorla, M.; Wolfe, G. M.; Bailey, S. A.; Swanson, A. K.; Arkinson, H. L.; Hanisco, T. F. (Copernicus, 2015-02-03)
      The NASA In Situ Airborne Formaldehyde (ISAF) instrument is a high-performance laser-based detector for gas-phase formaldehyde (HCHO). ISAF uses rotational-state specific laser excitation at 353 nm for laser-induced ...
    • New ALMA and Fermi/LAT Observations of the Large-scale Jet of PKS 0637−752 Strengthen the Case Against the IC/CMB Model 

      Meyer, Eileen T.; Breiding, Peter; Georganopoulos, Markos; Oteo, Iván; Zwaan, Martin A.; Laing, Robert; Godfrey, Leith; Ivison, R. J. (IOP, 2017-02-02)
      The Chandra X-ray observatory has discovered several dozen anomalously X-ray-bright jets associated with powerful quasars. A popular explanation for the X-ray flux from the knots in these jets is that relativistic ...
    • New high-resolution model developed for Earth’s gravitational field 

      Lemoine, Frank G.; Pavlis, Nikolaos K.; Kenyon, Steve C.; Rapp, Richard H.; Pavlis, E. C.; Chao, B. F (AGU Pubication, 2006-10-19)
    • A new laser-based and ultra-portable gas sensor for indoor and outdoor formaldehyde (HCHO) monitoring 

      Shutter, Joshua D.; Allen, Norton T.; Hanisco, Thomas F.; Wolfe, Glenn M.; St. Clair, Jason M.; Keutsch, Frank N. (Copernicus Publications, 2019-11-22)
      n this work, a new commercially available, laser-based, and ultra-portable formaldehyde (HCHO) gas sensor is characterized, and its usefulness for monitoring HCHO mixing ratios in both indoor and outdoor environments is ...
    • A new laser-ranged satellite for General Relativity and space geodesy: I. An introduction to the LARES2 space experiment 

      Ciufolini, Ignazio; Paolozzi, Antonio; Pavlis, Erricos C.; Sindoni, Giampiero; Koenig, Rolf; Ries, John C.; Matzner, Richard; Gurzadyan, Vahe; Penrose, Roger; Rubincam, David; Paris, Claudio (Springer Nature, 2017-08-04)
      We introduce the LARES 2 space experiment recently approved by the Italian Space Agency (ASI). The LARES 2 satellite is planned for launch in 2019 with the new VEGA C launch vehicle of ASI, ESA and ELV. The orbital analysis ...
    • A new laser-ranged satellite for General Relativity and space geodesy: II. Monte Carlo simulations and covariance analyses of the LARES 2 experiment 

      Ciufolini, Ignazio; Pavlis, Erricos C.; Sindoni, Giampiero; Ries, John C.; Paolozzi, Antonio; Matzner, Richard; Koenig, Rolf; Paris, Claudia (Springer Nature, 2017-08-04)
      In the previous paper we have introduced the LARES 2 space experiment. The LARES 2 laser-ranged satellite is planned for a launch in 2019 with the new VEGA C launch vehicle of the Italian Space Agency (ASI), ESA and ELV. ...
    • A new look at radio loud AGN unification 

      Georganopoulos, Markos; Meyer, Eileen T.; Fossati, Giovanni; Lister, Matthew L. (Sissa Medialab, 2012-06-20)
      We review some open issues on our understanding of the radio loud AGN unification and the blazar sequence, and discuss the results of our recent work [Meyer et al.(2011)] and current and future work in the direction of ...
    • A new non-resonant laser-induced fluorescence instrument for the airborne in situ measurement of formaldehyde 

      St. Clair, Jason M.; Swanson, Andrew K.; Bailey, Steven A.; Wolfe, Glenn M.; Marrero, Josette E.; Iraci, Laura T.; Hagopian, John G.; Hanisco, Thomas F. (Copernicus Publications, 2017-12-12)
      A new in situ instrument for gas-phase formaldehyde (HCHO), COmpact Formaldehyde FluorescencE Experiment (COFFEE), is presented. COFFEE utilizes non-resonant laser-induced fluorescence (NR-LIF) to measure HCHO, with 300 mW ...
    • The Next Geminga: Deep Multiwavelength Observations of a Neutron Star Identified with 3EG J1835+5918 

      Halpern, J. P.; Gotthelf, E. V.; Mirabal, N.; Camilo, F. (IOP, 2002-06-02)
      We describe Chandra, Hubble Space Telescope (HST), and radio observations that reveal a radio-quiet but magnetospherically active neutron star in the error circle of the high-energy γ-ray source 3EG J1835+5918, the brightest ...
    • The Next Generation X-ray Galaxy Survey with eROSITA 

      Basu-Zych, Antara R.; Hornschemeier, Ann E.; Haberl, Frank; Vulic, Neven; Wilms, Jörn; Zezas, Andreas; Kovlakas, Konstantinos; Ptak, Andrew; Dauser, Thomas (Oxford University Press, 2020-03-02)
      eROSITA, launched on 13 July 2019, will be completing the first all-sky survey in the soft and medium X-ray band in nearly three decades. This 4-year survey, finishing in late 2023, will present a rich legacy for the entire ...
    • Next-Generation Geodesy at the Lunar South Pole: An Opportunity Enabled by the Artemis III Crew 

      Viswanathan, Vishnu; Mazarico, Erwan; Merkowitz, Stephen; Sun, Xiaoli; Eubanks, Thomas Marshall; Smith, David Edmund (2020-09-08)
      Lunar retro-reflector arrays (LRAs) consisting of corner-cube reflectors (CCRs) placed on the nearside of the Moon during the Apollo era have demonstrated their longevity, cost-effectiveness, ease of deployment, and most ...