Institution
Jet Propulsion Laboratory
Facility•La Cañada Flintridge, California, United States•
About: Jet Propulsion Laboratory is a facility organization based out in La Cañada Flintridge, California, United States. It is known for research contribution in the topics: Mars Exploration Program & Telescope. The organization has 8801 authors who have published 14333 publications receiving 548163 citations. The organization is also known as: JPL & NASA JPL.
Topics: Mars Exploration Program, Telescope, Galaxy, Coronagraph, Planet
Papers published on a yearly basis
Papers
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Cardiff University1, University of Paris2, University of Paris-Sud3, University of Toulouse4, California Institute of Technology5, Jet Propulsion Laboratory6, Institut d'Astrophysique de Paris7, Sapienza University of Rome8, University of Oxford9, University of Grenoble10, University of Minnesota11, Maynooth University12, Landau Institute for Theoretical Physics13, DSM14
TL;DR: In this paper, the cosmological constraints that Archeops places on adiabatic cold dark matter models with passive power-law initial fluctuations were analyzed, and the spectral index n was measured to be 1.04 (+0.10, 0.12) when the optical depth to reionization, tau, is allowed to vary as a free parameter, and 0.96 (+ 0.03,0.04) when tau is fixed to zero, both in good agreement with inflation.
Abstract: We analyze the cosmological constraints that Archeops places on adiabatic cold dark matter models with passive power-law initial fluctuations. Because its angular power spectrum has small bins in l and large l coverage down to COBE scales, Archeops provides a precise determination of the first acoustic peak in terms of position at multipole l_peak=220 +- 6, height and width. An analysis of Archeops data in combination with other CMB datasets constrains the baryon content of the Universe, Omega(b)h^2 = 0.022 (+0.003,-0.004), compatible with Big-Bang nucleosynthesis and with a similar accuracy. Using cosmological priors obtainedfrom recent non-CMB data leads to yet tighter constraints on the total density, e.g. Omega(tot)=1.00 (+0.03,-0.02) using the HST determination of the Hubble constant. An excellent absolute calibration consistency is found between Archeops and other CMB experiments, as well as with the previously quoted best fit model.The spectral index n is measured to be 1.04 (+0.10,-0.12) when the optical depth to reionization, tau, is allowed to vary as a free parameter, and 0.96 (+0.03,-0.04) when tau is fixed to zero, both in good agreement with inflation.
228 citations
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University of Paris-Sud1, Paris Diderot University2, Aix-Marseille University3, University of Colorado Boulder4, Ames Research Center5, University of Edinburgh6, Max Planck Society7, California Institute of Technology8, Jet Propulsion Laboratory9, University of Hawaii10, University of La Laguna11, Spanish National Research Council12, Complutense University of Madrid13, Imperial College London14, University of California, Irvine15, Cardiff University16, University of Sussex17, University of Padua18, UK Astronomy Technology Centre19, University of British Columbia20, Institut d'Astrophysique de Paris21, University College London22, Rutherford Appleton Laboratory23, University of Lethbridge24, University of Oxford25, Commonwealth Scientific and Industrial Research Organisation26, Harvard University27, University of the Western Cape28, European Space Agency29
TL;DR: In this paper, the authors derived the number counts and redshift distributions of the bright SPIRE sources in the COSMOS field with a method using the positions, the flux densities, and the redshifts of the 24 μm sources as a prior.
Abstract: Aims. The Spectral and Photometric Imaging REceiver (SPIRE) onboard the Herschel space telescope has provided confusion limited maps of deep fields at 250 μm, 350 μm, and 500 μm, as part of the Herschel Multi-tiered Extragalactic Survey (HerMES). Unfortunately, due to confusion, only a small fraction of the cosmic infrared background (CIB) can be resolved into individually-detected sources. Our goal is to produce deep galaxy number counts and redshift distributions below the confusion limit at SPIRE wavelengths (~20 mJy), which we then use to place strong constraints on the origins of the cosmic infrared background and on models of galaxy evolution.
Methods. We individually extracted the bright SPIRE sources (>20 mJy) in the COSMOS field with a method using the positions, the flux densities, and the redshifts of the 24 μm sources as a prior, and derived the number counts and redshift distributions of the bright SPIRE sources. For fainter SPIRE sources (<20 mJy), we reconstructed the number counts and the redshift distribution below the confusion limit using the deep 24 μm catalogs associated with photometric redshift and information provided by the stacking of these sources into the deep SPIRE maps of the GOODS-N and COSMOS fields. Finally, by integrating all these counts, we studied the contribution of the galaxies to the CIB as a function of their flux density and redshift.
Results. Through stacking, we managed to reconstruct the source counts per redshift slice down to ~2 mJy in the three SPIRE bands, which lies about a factor 10 below the 5σ confusion limit. Our measurements place tight constraints on source population models. None of the pre-existing models are able to reproduce our results at better than 3-σ. Finally, we extrapolate our counts to zero flux density in order to derive an estimate of the total contribution of galaxies to the CIB, finding 10.1_(-2.3)^(+2.6) nW m^(-2) sr^(-1), 6.5_(-1.6)^(+1.7) nW m^(-2) sr^(-1), and 2.8_(-0.8)^(+0.9) nW m^(-2) sr^(-1) at 250 μm, 350 μm, and 500 μm, respectively. These values agree well with FIRAS absolute measurements, suggesting our number counts and their extrapolation are sufficient to explain the CIB. We find that half of the CIB is emitted at z = 1.04, 1.20, and 1.25, respectively. Finally, combining our results with other works, we estimate the energy budget contained in the CIB between 8 μm and 1000 μm: 26_(-3)^(+7) nW m^(-2) sr^(-1).
228 citations
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University of California, Berkeley1, Goddard Space Flight Center2, Centre national de la recherche scientifique3, Swedish Institute of Space Physics4, National Institute of Aerospace5, Boston University6, Princeton University7, University of Colorado Boulder8, Space Sciences Laboratory9, University of Arizona10, Wright State University11, University of Kansas12, University of Tokyo13, Tohoku University14, University of California, Los Angeles15, Max Planck Society16, University of New Brunswick17, Eastern Michigan University18, University of Michigan19, Planetary Science Institute20, United States Naval Research Laboratory21, Jet Propulsion Laboratory22
TL;DR: In this article, the authors used observations of the Mars upper atmosphere made from the Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft to determine the loss rates of gas from the upper atmosphere to space for a complete Mars year (16 Nov 2014 − 3 Oct 2016).
227 citations
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TL;DR: The detection by Cassini's Imaging Science Subsystem of a large low-latitude cloud system early in Titan’s northern spring and extensive surface changes in the wake of this storm are reported, which suggests that the dry channels observed at Titan's low latitudes are carved by seasonal precipitation.
Abstract: Although there is evidence that liquids have flowed on the surface at Titan’s equator in the past, to date, liquids have only been confirmed on the surface at polar latitudes, and the vast expanses of dunes that dominate Titan’s equatorial regions require a predominantly arid climate. We report the detection by Cassini’s Imaging Science Subsystem of a large low-latitude cloud system early in Titan’s northern spring and extensive surface changes (spanning more than 500,000 square kilometers) in the wake of this storm. The changes are most consistent with widespread methane rainfall reaching the surface, which suggests that the dry channels observed at Titan’s low latitudes are carved by seasonal precipitation.
227 citations
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17 Mar 2002TL;DR: A review of the status of the EAP field and the challenges to practical application of EAP materials as actuators is presented in this article, where the basic principles are studied using comprehensive material science, electro-mechanics analytical tools and improved material processing techniques to gain better understanding of the parameters that control the electro-activation force and deformation.
Abstract: In the last ten years, new EAP materials have emerged that exhibit large displacement in response to electrical stimulation enabling great potential for the field. To develop efficient and robust EAP material for practical applications efforts are underway to understand the behavior of EAP materials and improved characterization techniques. Further, to enhance the actuation force the basic principles are being studied using comprehensive material science, electro-mechanics analytical tools and improved material processing techniques to gain better understanding of the parameters that control the EAP electro-activation force and deformation. The processes of synthesizing, fabricating, electroding, shaping and handling are being refined to maximize the EAP materials actuation capability and robustness. Methods of reliably characterizing the response of these materials are required to establish database with documented material properties in order to support design engineers considering use of these materials and towards making EAP as actuators of choice. Various configurations of EAP actuators and sensors need to be studied and modeled to produce an arsenal of effective smart EAP driven system. The development of the infrastructure is a multidisciplinary task involving materials science, chemistry, electro-mechanics, computers, electronics, and others. This paper will be a review of the status of the EAP field and the challenges to practical application of EAP materials as actuators.
227 citations
Authors
Showing all 9033 results
Name | H-index | Papers | Citations |
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B. P. Crill | 148 | 486 | 111895 |
George Helou | 144 | 662 | 96338 |
H. K. Eriksen | 141 | 474 | 104208 |
Charles R. Lawrence | 141 | 528 | 104948 |
W. C. Jones | 140 | 395 | 97629 |
Gianluca Morgante | 138 | 478 | 98223 |
Jean-Paul Kneib | 138 | 805 | 89287 |
Kevin M. Huffenberger | 138 | 402 | 93452 |
Robert H. Brown | 136 | 1174 | 79247 |
Federico Capasso | 134 | 1189 | 76957 |
Krzysztof M. Gorski | 132 | 380 | 105912 |
Olivier Doré | 130 | 427 | 104737 |
Mark E. Thompson | 128 | 527 | 77399 |
Clive Dickinson | 123 | 501 | 80701 |
Daniel Stern | 121 | 788 | 69283 |