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1.
N. Narukage T. Sakao R. Kano H. Hara M. Shimojo T. Bando F. Urayama E. DeLuca L. Golub M. Weber P. Grigis J. Cirtain S. Tsuneta 《Solar physics》2011,269(1):169-236
The X-Ray Telescope (XRT) onboard the Hinode satellite is an X-ray imager that observes the solar corona with unprecedentedly high angular resolution (consistent with its 1?? pixel size). XRT has nine X-ray analysis filters with different temperature responses. One of the most significant scientific features of this telescope is its capability of diagnosing coronal temperatures from less than 1 MK to more than 10 MK, which has never been accomplished before. To make full use of this capability, accurate calibration of the coronal temperature response of XRT is indispensable and is presented in this article. The effect of on-orbit contamination is also taken into account in the calibration. On the basis of our calibration results, we review the coronal-temperature-diagnostic capability of XRT. 相似文献
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Rocky Dunlap Leo Mark Spencer Rugaber V. Balaji Julien Chastang Luca Cinquini Cecelia DeLuca Don Middleton Sylvia Murphy 《Earth Science Informatics》2008,1(3-4):131-149
The Earth System Curator is a National Science Foundation sponsored project developing a metadata formalism for describing the digital resources used in climate simulations. The primary motivating observation of the project is that a simulation/model’s source code plus the configuration parameters required for a model run are a compact representation of the dataset generated when the model is executed. The end goal of the project is a convergence of models and data where both resources are accessed uniformly from a single registry. In this paper we review the current metadata landscape of the climate modeling community, present our work on developing a metadata formalism for describing climate models, and reflect on technical challenges we have faced that require new research in the area of Earth Science Informatics. 相似文献
4.
The active region NOAA AR 8331 was a target of an international ground-based observational campaign in the Canaries and coordinated with space instruments (TRACE and Yohkoh). We focus our study on observations obtained with the SVST at LaPalma, and with TRACE. On 10 September 1998, arch-filament systems were observed with high spatial and temporal resolution, from the lower to the upper atmosphere of the Sun, during five hours. Flux tubes emerged with increasing shear, which apparently led to energy release and heating in the overlying corona. A model for filament formation by the emergence of U-shaped loops from the subphotosphere, as proposed by Rust and Kumar (1994), is supported by the present observations. The coronal response to these events is visualized by rising, medium-scale loop brightenings. The low-lying X-ray loops show short-lived, bright knots which are thought to result from interaction between different loop systems. 相似文献
5.
Lenz Dawn D. DeLuca Edward E. Golub Leon Rosner Robert Bookbinder Jay A. Litwin Christof Reale Fabio Peres Giovanni 《Solar physics》1999,190(1-2):131-138
An initial study of long-lived loops observed with TRACE (Lenz et al., 1999) shows that they have no significant temperature stratification and that they are denser than the classic loop model
predicts. Models that agree better with the observations include a loop consisting of a bundle of filaments at different temperatures
and a loop with momentum input by MHD waves. Some implications for coronal heating models and mechanisms are discussed. 相似文献
6.
A. S. Savcheva S. C. McKillop P. I. McCauley E. M. Hanson E. E. DeLuca 《Solar physics》2014,289(9):3297-3311
We present a new sigmoid catalog covering the duration of the Hinode mission and the Solar Dynamics Observatory (SDO) until the end of 2012. The catalog consists of 72 mostly long-lasting sigmoids. We collect and make available all X-ray and EUV data from Hinode, SDO, and the Solar TErrestrial RElations Observatory (STEREO), and we determine the sigmoid lifetimes, sizes, and aspect ratios. We also collect the line-of-sight magnetograms from the Helioseismic and Magnetic Imager (HMI) for SDO or the Michelson Doppler Imager (MDI) on the Solar and Heliospheric Observatory (SOHO) to measure flux versus time for the lifetime of each region. We determine that the development of a sigmoidal shape and eruptive activity is more strongly correlated with flux cancelation than with emergence. We find that the eruptive properties of the regions correlate well with the maximum flux, largest change, and net change in flux in the regions. These results have implications for constraining future flux-rope models of ARs and gaining insight into their evolutionary properties. 相似文献
7.
L. Golub E. DeLuca G. Austin J. Bookbinder D. Caldwell P. Cheimets J. Cirtain M. Cosmo P. Reid A. Sette M. Weber T. Sakao R. Kano K. Shibasaki H. Hara S. Tsuneta K. Kumagai T. Tamura M. Shimojo J. McCracken J. Carpenter H. Haight R. Siler E. Wright J. Tucker H. Rutledge M. Barbera G. Peres S. Varisco 《Solar physics》2007,243(1):63-86
The X-ray Telescope (XRT) of the Hinode mission provides an unprecedented combination of spatial and temporal resolution in solar coronal studies. The high sensitivity
and broad dynamic range of XRT, coupled with the spacecraft’s onboard memory capacity and the planned downlink capability
will permit a broad range of coronal studies over an extended period of time, for targets ranging from quiet Sun to X-flares.
This paper discusses in detail the design, calibration, and measured performance of the XRT instrument up to the focal plane.
The CCD camera and data handling are discussed separately in a companion paper. 相似文献
8.
R. Kano T. Sakao H. Hara S. Tsuneta K. Matsuzaki K. Kumagai M. Shimojo K. Minesugi K. Shibasaki E. E. DeLuca L. Golub J. Bookbinder D. Caldwell P. Cheimets J. Cirtain E. Dennis T. Kent M. Weber 《Solar physics》2008,249(2):263-279
The X-ray Telescope (XRT) aboard the Hinode satellite is a grazing incidence X-ray imager equipped with a 2048×2048 CCD. The XRT has 1 arcsec pixels with a wide field
of view of 34×34 arcmin. It is sensitive to plasmas with a wide temperature range from < 1 to 30 MK, allowing us to obtain
TRACE-like low-temperature images as well as Yohkoh/SXT-like high-temperature images. The spacecraft Mission Data Processor (MDP) controls the XRT through sequence tables with
versatile autonomous functions such as exposure control, region-of-interest tracking, flare detection, and flare location
identification. Data are compressed either with DPCM or JPEG, depending on the purpose. This results in higher cadence and/or
wider field of view for a given telemetry bandwidth. With a focus adjust mechanism, a higher resolution of Gaussian focus
may be available on-axis. This paper follows the first instrument paper for the XRT (Golub et al., Solar Phys.
243, 63, 2007) and discusses the design and measured performance of the X-ray CCD camera for the XRT and its control system with the MDP. 相似文献
9.
Jason C. Leppi Thomas H. DeLuca Solomon W. Harrar Steven W. Running 《Climatic change》2012,112(3-4):997-1014
In the snowmelt dominated hydrology of arid western US landscapes, late summer low streamflow is the most vulnerable period for aquatic ecosystem habitats and trout populations. This study analyzes mean August discharge at 153 streams throughout the Central Rocky Mountains of North America (CRMs) for changes in discharge from 1950–2008. The purpose of this study was to determine if: (1) Mean August stream discharge values have decreased over the last half-century; (2) Low discharge values are occurring more frequently; (3) Climatic variables are influencing August discharge trends. Here we use a strict selection process to characterize gauging stations based on amount of anthropogenic impact in order to identify heavily impacted rivers and understand the relationship between climatic variables and discharge trends. Using historic United States Geologic Survey discharge data, we analyzed data for trends of 40–59 years. Combining of these records along with aerial photos and water rights records we selected gauging stations based on the length and continuity of discharge records and categorized each based on the amount of diversion. Variables that could potentially influence discharge such as change in vegetation and Pacific Decadal Oscillation (PDO) were examined, but we found that that both did not significantly influence August discharge patterns. Our analyses indicate that non-regulated watersheds are experiencing substantial declines in stream discharge and we have found that 89% of all non-regulated stations exhibit a declining slope. Additionally our results here indicate a significant (α?≤?0.10) decline in discharge from 1951–2008 for the CRMs. Correlations results at our pristine sites show a negative relationship between air temperatures and discharge and these results coupled with increasing air temperature trends pose serious concern for aquatic ecosystems in CRMs. 相似文献
10.
P. MacCarthy S.J. DeLuca K.J. Voorhees R.L. Malcolm E.M. Thurman 《Geochimica et cosmochimica acta》1985,49(10):2091-2096
A suite of well-characterized humic and fulvic acids of freshwater, soil and plant origin was subjected to pyrolysis-mass spectrometry and the resulting data were analyzed by pattern recognition and factor analysis. A factor analysis plot of the data shows that the humic acids and fulvic acids can be segregated into two distinct classes. Carbohydrate and phenolic components are more pronounced in the pyrolysis products of the fulvic acids, and saturated and unsaturated hydrocarbons contribute more to the humic acid pyrolysis products. A second factor analysis plot shows a separation which appears to be based primarily on whether the samples are of aquatic or soil origin. 相似文献