Spatial and temporal variations of solar coronal loops     

S. R. Habbal  R. Ronan  G. L. Withbroe 《Solar physics》1985,98(2):323-340

Skylab EUV observations of an active region near the solar limb were analyzed. Both cool (T < 10⁶ K) and hot (T > 10⁶ K) loops were observed in this region. For the hot loops the observed intensity variations were small, typically a few percent over a period of 30 min. The cool loops exhibited stronger variations, sometimes appearing and disappearing in 5 to 10 min. Most of the cool material observed in the loops appeared to be caused by the downward flow of coronal rain and by the upward ejection of chromospheric material in surges. The frequent EUV brightenings observed near the loop footpoints appear to have been produced by both in situ transient energy releases (e.g. subflares) and the infall/impact of coronal rain. The physical conditions in the loops (temperatures, densities, radiative and conducting cooling rates, cooling times) were determined. The mean energy required to balance the radiative and conductive cooling of the hot loops is approximately 3 × 10^–3 erg cm^–3 s^–1. One coronal heating mechanism that can account for the observed behavior of the EUV emission from McMath region 12634 is heating by the dissipation of fast mode MHD waves.  相似文献   

Establishing stakeholder connections for management of the Irish orange roughy fishery     

Shephard  Samuel; Connolly  Paul; Hareide  Nils-Roar; Rogan  Emer 《ICES Journal of Marine Science》2007,64(4):841-845

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Fisheries Management Strategies: an introduction by the Conveners     

Rice  Jake C.; Connolly  Paul L. 《ICES Journal of Marine Science》2007,64(4):577-579

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An automated strategy for calculation of phase diagram sections and retrieval of rock properties as a function of physical conditions   总被引：9，自引：0，他引：9  

J. A. D. Connolly  K. Petrini 《Journal of Metamorphic Geology》2002,20(7):697-708

We formulate an algorithm for the calculation of stable phase relations of a system with constrained bulk composition as a function of its environmental variables. The basis of this algorithm is the approximate representation of the free energy composition surfaces of solution phases by inscribed polyhedra. This representation leads to discretization of high variance phase fields into a continuous mesh of smaller polygonal fields within which the composition and physical properties of the phases are uniquely determined. The resulting phase diagram sections are useful for understanding the phase relations of complex metamorphic systems and for applications in which it is necessary to establish the variations in rock properties such as density, seismic velocities and volatile‐content through a metamorphic cycle. The algorithm has been implemented within a computer program that is general with respect to both the choice of variables and the number of components and phases possible in a system, and is independent of the structure of the equations of state used to describe the phases of the system.  相似文献   

Quantifying flows along hydrological pathways by applying a new filtering algorithm in conjunction with master recession curve analysis          下载免费PDF全文

Ronan J. O'Brien  Bruce D. Misstear  Laurence W. Gill  Paul M. Johnston  Raymond Flynn 《水文研究》2014,28(26):6211-6221

Quantifying the proportion of the river hydrograph derived from the different hydrological pathways is essential for understanding the behaviour of a catchment. This paper describes a new approach using the output from master recession curve analysis to inform a new algorithm based on the Lyne and Hollick ‘one‐parameter’ signal analysis filtering algorithm. This approach was applied to six catchments (including two subcatchments of these) in Ireland. The conceptual model for each catchment consists of four main flow pathways: overland flow, interflow, shallow groundwater and deep groundwater. The results were compared with those of the master recession curve analysis, a recharge coefficient approach developed in Ireland and the semi‐distributed, lumped and deterministic hydrological model Nedbør‐Afstrømings‐Model. The new algorithm removes the ‘free variable’ aspect that is typically associated with filtering algorithms and provides a means of estimating the contribution of each pathway that is consistent with the results of hydrograph separation in catchments that are dominated by quick response pathways. These types of catchments are underlain by poorly productive aquifers that are not capable of providing large baseflows in the river. Such aquifers underlie over 73% of Ireland, ensuring that this new algorithm is applicable in the majority of catchments in Ireland and potentially in those catchments internationally that are strongly influenced by the quick‐responding hydrological pathways. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

Phase diagram methods for graphitic rocks and application to the system C−O−H−FeO−TiO2−SiO2     

J. A. D. Connolly 《Contributions to Mineralogy and Petrology》1995,119(1):94-116

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The Meteoritical Bulletin,No. 91, 2007 March     

Harold C. Connolly  Jutta Zipfel  Luigi Folco  Caroline Smith  Rhian H. Jones  Gretchen Benedix  Kevin Righter  Akira Yamaguchi  Hasnaa Chennaoui Aoudjehane  Jeffrey N. Grossman 《Meteoritics & planetary science》2007,42(3):413-466

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Galaxy–galaxy weak lensing in the Sloan Digital Sky Survey: intrinsic alignments and shear calibration errors     

Christopher M. Hirata  Rachel Mandelbaum  Uro&#; Seljak  Jacek Guzik  Nikhil Padmanabhan  Cullen Blake  Jonathan Brinkmann  Tamas Budávari  rew Connolly  Istvan Csabai  Ryan Scranton  Alexander S. Szalay 《Monthly notices of the Royal Astronomical Society》2004,353(2):529-549

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The OSIRIS‐REx target asteroid (101955) Bennu: Constraints on its physical,geological, and dynamical nature from astronomical observations          下载免费PDF全文

D. S. Lauretta  A. E. Bartels  M. A. Barucci  E. B. Bierhaus  R. P. Binzel  W. F. Bottke  H. Campins  S. R. Chesley  B. C. Clark  B. E. Clark  E. A. Cloutis  H. C. Connolly  M. K. Crombie  M. Delbó  J. P. Dworkin  J. P. Emery  D. P. Glavin  V. E. Hamilton  C. W. Hergenrother  C. L. Johnson  L. P. Keller  P. Michel  M. C. Nolan  S. A. Sandford  D. J. Scheeres  A. A. Simon  B. M. Sutter  D. Vokrouhlický  K. J. Walsh 《Meteoritics & planetary science》2015,50(4):834-849

We review the results of an extensive campaign to determine the physical, geological, and dynamical properties of asteroid (101955) Bennu. This investigation provides information on the orbit, shape, mass, rotation state, radar response, photometric, spectroscopic, thermal, regolith, and environmental properties of Bennu. We combine these data with cosmochemical and dynamical models to develop a hypothetical timeline for Bennu's formation and evolution. We infer that Bennu is an ancient object that has witnessed over 4.5 Gyr of solar system history. Its chemistry and mineralogy were established within the first 10 Myr of the solar system. It likely originated as a discrete asteroid in the inner Main Belt approximately 0.7–2 Gyr ago as a fragment from the catastrophic disruption of a large (approximately 100‐km), carbonaceous asteroid. It was delivered to near‐Earth space via a combination of Yarkovsky‐induced drift and interaction with giant‐planet resonances. During its journey, YORP processes and planetary close encounters modified Bennu's spin state, potentially reshaping and resurfacing the asteroid. We also review work on Bennu's future dynamical evolution and constrain its ultimate fate. It is one of the most Potentially Hazardous Asteroids with an approximately 1‐in‐2700 chance of impacting the Earth in the late 22nd century. It will most likely end its dynamical life by falling into the Sun. The highest probability for a planetary impact is with Venus, followed by the Earth. There is a chance that Bennu will be ejected from the inner solar system after a close encounter with Jupiter. OSIRIS‐REx will return samples from the surface of this intriguing asteroid in September 2023.  相似文献   

The effect of sideband ratio on line intensity for Herschel/HIFI     

Ronan Higgins  David Teyssier  Colin Borys  Jonathan Braine  Claudia Comito  Bertrand Delforge  Frank Helmich  Michael Olberg  Volker Ossenkopf  John Pearson  Russell Shipman 《Experimental Astronomy》2014,37(2):433-452

The Heterodyne Instrument for the Far Infrared (HIFI) on board the Herschel Space Observatory is composed of a set of fourteen double sideband mixers. We discuss the general problem of the sideband ratio (SBR) determination and the impact of an imbalanced sideband ratio on the line calibration in double sideband heterodyne receivers. The HIFI SBR is determined from a combination of data taken during pre-launch gas cell tests and in-flight. The results and some of the calibration artefacts discovered in the gas cell test data are presented here along with some examples of how these effects appear in science data taken in orbit.  相似文献