An improved multiple-frequency method for measuring in situ target strengths     

Conti  Stephane G.; Demer  David A.; Soule  Michael A.; Conti  Jean H.E. 《ICES Journal of Marine Science》2005,62(8):1636-1646

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Validation of the stochastic distorted-wave Born approximation model with broad bandwidth total target strength measurements of Antarctic krill   总被引：2，自引：0，他引：2  

Demer  David A; Conti  Stephane G 《ICES Journal of Marine Science》2004,61(1):155-156

In the computations of SDWBA_TTS(f) in Figure 4, the scatteredvector was integrated over all orientations in the XY plane,where X is the main axis of the krill, but a factor of 2 was  相似文献   

New target-strength model indicates more krill in the Southern Ocean   总被引：5，自引：3，他引：5  

Demer  David A.; Conti  Stephane G. 《ICES Journal of Marine Science》2005,62(1):25-32

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A north-south section across the Queyras Schistes lustrés (Piedmont zone, Western Alps): Syn-collision refolding of a subduction wedge     

Pierre Tricart  Stephane Schwartz 《Eclogae Geologicae Helvetiae》2006,99(3):429-442

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Asymptotic Analysis and Layer Decomposition for the Couplex Exercise     

Stephane Del Pino  Olivier Pironneau 《Computational Geosciences》2004,8(2):149-162

This document explores the possibilities of multiscale expansions and domain decomposition to solve part of the Couplex 1 exercise. We concentrate on the hydrostatic pressure and show that the slenderness of the domain and the large variations of the Darcy constants allows an analytical approximation which our test reveals to be true to relative errors smaller than 10^–3. The numerical tests are done in 2D with freefem+ and in 3D with freefem3D. Some considerations are also given for Iodine transport.  相似文献   

Mesoscale distribution of zooplankton biomass in the northeast Atlantic Ocean determined with an Optical Plankton Counter: Relationships with environmental structures     

Jean-Philippe Labat  Stephane Gasparini  Laure Mousseau  Louis Prieur  Marc Boutoute  Patrick Mayzaud   《Deep Sea Research Part I: Oceanographic Research Papers》2009,56(10):1742-1756

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WASP-1b and WASP-2b: two new transiting exoplanets detected with SuperWASP and SOPHIE   总被引：1，自引：0，他引：1  

A. Collier Cameron  F. Bouchy  G. Hébrard  P. Maxted  D. Pollacco  F. Pont  I. Skillen  B. Smalley  R. A. Street  R. G. West  D. M. Wilson  S. Aigrain  D. J. Christian  W. I. Clarkson  B. Enoch  A. Evans  A. Fitzsimmons  M. Fleenor  M. Gillon  C. A. Haswell  L. Hebb  C. Hellier  S. T. Hodgkin  K. Horne  J. Irwin  S. R. Kane  F. P. Keenan  B. Loeillet  T. A. Lister  M. Mayor  C. Moutou  A. J. Norton  J. Osborne  N. Parley  D. Queloz  R. Ryans  A. H. M. J. Triaud  S. Udry  P. J. Wheatley 《Monthly notices of the Royal Astronomical Society》2007,375(3):951-957

We have detected low-amplitude radial-velocity variations in two stars, USNO-B1.0 1219–0005465 (GSC  02265–00107 = WASP–1  ) and USNO-B1.0 0964–0543604 (GSC  00522–01199 = WASP–2  ). Both stars were identified as being likely host stars of transiting exoplanets in the 2004 SuperWASP wide-field transit survey. Using the newly commissioned radial-velocity spectrograph SOPHIE at the Observatoire de Haute-Provence, we found that both objects exhibit reflex orbital radial-velocity variations with amplitudes characteristic of planetary-mass companions and in-phase with the photometric orbits. Line-bisector studies rule out faint blended binaries as the cause of either the radial-velocity variations or the transits. We perform preliminary spectral analyses of the host stars, which together with their radial-velocity variations and fits to the transit light curves yield estimates of the planetary masses and radii. WASP-1b and WASP-2b have orbital periods of 2.52 and 2.15 d, respectively. Given mass estimates for their F7V and K1V primaries, we derive planet masses 0.80–0.98 and 0.81–0.95 times that of Jupiter, respectively. WASP-1b appears to have an inflated radius of at least 1.33 R _Jup, whereas WASP-2b has a radius in the range 0.65–1.26 R _Jup.  相似文献   

Reconciling theoretical versus empirical target strengths of krill: effects of phase variability on the distorted-wave Born approximation     

Demer  David A; Conti  Stephane G 《ICES Journal of Marine Science》2004,61(1):157-158

In the caption for Figure 5, it was erroneously stated thatthe TS curves were normalized to L = 31.6 mm. They were normalizedto L = 38.35  相似文献   

Investigating the igneous petrogenesis of Martian volcanic rocks using augite quantitative textural analysis of the Yamato nakhlites     

Sammy Griffin  Arya Udry  Luke Daly  Lucy Victoria Forman  Martin R. Lee  Benjamin E. Cohen 《Meteoritics & planetary science》2023,58(1):63-84

To better understand volcanism on planetary bodies other than the Earth, the quantification of physical processes is needed. Here, the petrogenesis of the achondrite Martian Yamato (Y) nakhlites (Y 000593, Y 000749, and Y 000802) is reinvestigated via quantitative analysis of augite (high-Ca clinopyroxene) phenocrysts: crystal size distribution (CSD), spatial distribution patterns (SDP), and electron backscatter diffraction (EBSD). Results from CSD and EBSD quantitative data sets show augite to have continuous uninterrupted growth resulting in calculated minimum magma chamber residence times of either 88–117 ± 6 yr or 9–12 yr. All samples exhibit low-intensity S-LS type crystallographic preferred orientation. Directional strain is observed across all samples with intracrystalline misorientation patterns indicative of (100)[001]:(001)[100] (Y 000593 and Y 000802) and {110}<001>or {110}¹/₂<110> (Y 000749) slip systems. SDP results indicate phenocryst-bearing crystal-clustered rock signatures. Combined findings from this work show that the Yamato nakhlites formed on Mars as individual low-viscosity lava flows or sills. This study shows that through combining these different quantitative techniques over multiple samples, one can more effectively compare and interpret resulting data to gain a more robust, geologically contextualized petrogenetic understanding of the rock suite being studied. The techniques used in this study should be equally applicable to igneous achondrites from other parent bodies.  相似文献   

Petrology and trace element geochemistry of Tissint,the newest shergottite fall          下载免费PDF全文

J. Brian Balta  Matthew E. Sanborn  Arya Udry  Meenakshi Wadhwa  Harry Y. McSween 《Meteoritics & planetary science》2015,50(1):63-85

The fall and recovery of the Tissint meteorite in 2011 created a rare opportunity to examine a Martian sample with a known, short residence time on Earth. Tissint is an olivine‐phyric shergottite that accumulated olivine antecrysts within a single magmatic system. Coarse olivine grains with nearly homogeneous cores of Mg# >80 suggest slow re‐equilibration. Many macroscopic features of this sample resemble those of LAR 06319, including the olivine crystal size distribution and the presence of evolved oxide and olivine compositions. Unlike LAR 06319, however, no magmatic hydrous phases were found in the analyzed samples of Tissint. Minor and trace element compositions indicate that the meteorite is the product of closed‐system crystallization from a parent melt derived from a depleted source, with no obvious addition of a LREE‐rich (crustal?) component prior to or during crystallization. The whole‐rock REE pattern is similar to that of intermediate olivine‐phyric shergottite EETA 79001 lithology A, and could also be approximated by a more olivine‐rich version of depleted basaltic shergottite QUE 94201. Magmatic oxygen fugacities are at the low end of the shergottite range, with log fO₂ of QFM‐3.5 to ‐4.0 estimated based on early‐crystallized minerals and QFM‐2.4 estimated based on the Eu in pyroxene oxybarometer. These values are similarly comparable to other depleted shergottites, including SaU 005 and QUE 94201. Tissint occupies a previously unsampled niche in shergottite chemistry: containing olivines with Mg# >80, resembling the enriched olivine‐phyric shergottite LAR 06319 in its crystallization path, and comparable to intermediate olivine‐phyric shergottite EETA 79001A, depleted olivine‐phyric shergottite DaG 476, and depleted basaltic shergottite QUE 94201 in its trace element abundances and oxygen fugacity. The apparent absence of evidence for terrestrial alteration in Tissint (particularly in trace element abundances in the whole‐rock and individual minerals) confirms that exposure to the arid desert environment results in only minimal weathering of samples, provided the exposure times are brief.  相似文献