Near- and mid-infrared colours of star-forming galaxies in European Large Area ISO Survey fields     

P. Väisänen  T. Morel  M. Rowan-Robinson  S. Serjeant  S. Oliver  T. Sumner  H. Crockett  C. Gruppioni  E. V. Tollestrup 《Monthly notices of the Royal Astronomical Society》2002,337(3):1043-1058

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Large-scale wind structures in OB supergiants: a search for rotationally modulated Hα variability     

T. Morel  S. V. Marchenko  A. K. Pati  K. Kuppuswamy  M. T. Carini  E. Wood  R. Zimmerman 《Monthly notices of the Royal Astronomical Society》2004,351(2):552-568

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Apport des isotopes stables dans l'estimation des altitudes de recharge de sources thermales du MarocRecharge altitude estimation of thermal springs using stable isotopes in Morocco     

Anne Winckel  Christelle Marlin  Laurent Dever  Jean-Luc Morel  Karim Morabiti  Mohamed Ben Makhlouf  Ahmed Chalouan 《Comptes Rendus Geoscience》2002,334(7):469-474

The recharge altitude estimation of thermal springs from northern and eastern Morocco using ¹⁸O and ²H contents requires the definition of regional isotopic altitudinal gradients (?0.25‰ for 100 m for the Rif and ?0.30‰ for the East) and the calculation of residence time using ¹⁴C. The altitudes of emergence vary widely between 170 and 1040 m under the altitude of the recharge areas. The ¹⁸O and ²H compositions of palaeowaters ($\text{>10}\text{000}$ yr BP) indicate two effects, altitude and palaeoclimate. To cite this article: A. Winckel et al., C. R. Geoscience 334 (2002) 469–474.  相似文献   

板状绿柱石晶体的结构测定   总被引：12，自引：0，他引：12  

郭延军 Fontan  F 《地质论评》2000,46(3):312-317

自然界中绿柱石晶体多为柱状,具板状晶形的绿柱石非常少见。本文对产于四川雪宝顶云英岩晶洞中的无色透明板状绿柱石进行了精确的结构分析,并与产于阿尔泰山号伟晶岩脉中的柱状绿柱石进行了比较。与阿尔泰柱状绿柱石相比,雪面板状绿石富Ｌi、Ｎａ,ｃ／ａ值较高,为１．００１,属钠－锂绿柱石或“四面体”绿柱石。本文还对这种特殊形貌柱石的形成机制进行了初步讨论,成矿流体中Ｌi的浓度以及Ｓi的化学形态可能是影响柱石忻驳闹  相似文献   

Calibration observations of Fomalhaut with the VLTI     

J. Davis  A. Richichi  P. Ballester  Ph. Gitton  A. Glindemann  S. Morel  M. Schoeller  M. Wittkowski  F. Paresce 《Astronomische Nachrichten》2005,326(1):25-30

An investigation of the stability of the transfer function of the European Southern Observatory's Very Large Telescope Interferometer has been carried out through observations of Fomalhaut, which was observed over a range in hour angle from 21:50–05:24 on 20 October 2002. No significant variation in the transfer function was found for the zenith angle range 5°–70°. The projected baseline varied between 139.7 m and 49.8 m during the observations and, as an integral part of the determination of the transfer function, a new accurate limb‐darkened angular diameter for Fomalhaut of 2.109 ± 0.013 mas has been established. This has led to improved values for the emergent flux = (3.43 ± 0.10)×10⁸ Wm⁻², effective temperature = 8819 ± 67 K and radius = (1.213 ± 0.011)×10⁹ m (R/R_⊙ = 1.744 ± 0.016). The luminosity has been found to be (6.34 ± 0.20)×10²⁷ W (L/L_⊙ = 16.5 ± 0.5). (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

Chronic offshore loss of nourishment on Nice beach,French Riviera: A case of over-nourishment of a steep beach?     

Edward J. Anthony  Olivier Cohen  Francois Sabatier 《Coastal Engineering》2011

The 4.5 km-long gravel beach fronting the exclusive resort of the city of Nice, on the French Riviera, in southeastern France, was artificially nourished from 1976 to 2005 to the tune of 558,000 m³, making this long-term operation one of the most significant for gravel beaches in the world. Nourishment has ranged from nil in certain years (1979, 1980, 1983–85, and 2001–2002) to a peak of over 97,000 m³ in 2000. Analyses of 50 transects covering the beach highlight no significant change in net beach width over this 30-year period of massive gravel nourishment. A Principal Components Analysis and a Cluster Analysis used to detect patterns in the 87 beach-width measurement dataset show no clear spatial trends in transect groups that can be interpreted in terms of the morphology of the beach and the steep inner shoreface. Significant wave height off Nice shows no change over the period 1979–2005. Since there is no possibility for alongshore gravel leakage on the strongly embayed Nice beach, the relative stability in beach width clearly implies loss of recharged gravel offshore. Gravel loss following nourishment is favoured by: (1) the steep inner shoreface inherited from the geological context of Nice beach at the flanks of the southern Alps, and (2) the practise of artificial beach widening through flattening, in summer, of a narrow (5–15 m-wide) mobile zone of the profile in order to enhance the ‘carrying’ capacity of this highly touristic beach. Beach widening and flattening following nourishment bring close to the very steep inner shoreface zone several cubic metres of gravel for each metre of beach that may be permanently lost downslope during autumn and winter storms. Recharged gravel is redistributed alongshore and offshore leakage is probably enhanced where small narrow submarine canyon heads impinge on the beach, resulting in a very narrow shoreface. Mean beach width shows an oscillating alongshore pattern that may be due to the influence of these canyons as pathways of gravel loss offshore. However, there is no correlation between mean beach width and distance to the 10-m isobath, used as a surrogate for inner shoreface width. Storms are associated with plunging waves that are particularly effective and concentrated, on this almost tideless shore, over the narrow mobile zone of the beach profile where a series of steep reflective berms are built during storms. The high dynamic pressures associated with this narrow zone of concentrated wave breaking, and energy reflection from the steepened profile, are deemed to contribute to the permanent downslope loss of gravel. This situation of long-term gravel loss is probably accepted by the beach management authority because of the low cost of obtaining nourishment material and the advantages derived from a temporarily wider beach in terms of recreational space.  相似文献   

Examining the impact of multiple climate forcings on simulated Southern Hemisphere climate variability     

Beraki  Asmerom F.  Morioka  Yushi  Engelbrecht  Francois A.  Nonaka  Masami  Thatcher  Marcus  Kobo  Nomkwezane  Behera  Swadhin 《Climate Dynamics》2020,54(11):4775-4792

Climate Dynamics - The study examines the influence of external climate forcings, and atmosphere–ocean–sea–ice coupled interaction on the Southern Hemisphere (SH) atmospheric...  相似文献   

Interferometric Observation at Mid-Infrared Wave-lengths with MIDI     

Frank Przygodda  O. Chesneau  U. Graser  Ch. Leinert  S. Morel 《Astrophysics and Space Science》2003,286(1-2):85-91

MIDI, the MID-Infrared Interferometricnterferometric Instrument for ESO's Very Large Telescope Interferometer (VLTI), will be the first instrument for combining mid-infrared light directly in order to obtain angular resolution up to 10 mas (assuming a 200 m baseline) in a wavelength range from 8 to 13 μm. Currently in the phase of commissioning at Paranal, the start of its scientific operation is expected for summer 2003. Direct interferometry at thermal infrared wavelengths demands special requirements on the instrument and also on the procedures of preparation of data reduction. Hereafter MIDI's different observing modes are described and an example for an interferometric observation is given. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

MIDI – the 10 μm instrument on the VLTI     

Ch. Leinert  U. Graser  F. Przygodda  L.B.F.M. Waters  G. Perrin  W. Jaffe  B. Lopez  E.J. Bakker  A. Böhm  O. Chesneau  W.D. Cotton  S. Damstra  J. de Jong  A.W. Glazenborg-Kluttig  B. Grimm  H. Hanenburg  W. Laun  R. Lenzen  S. Ligori  R.J. Mathar  J. Meisner  S. Morel  W. Morr  U. Neumann  J.-W. Pel  P. Schuller  R.-R. Rohloff  B. Stecklum  C. Storz  O. von der Lühe  K. Wagner 《Astrophysics and Space Science》2003,286(1-2):73-83

After more than five years of preparation, the mid-infrared interferometric instrument MIDI has been transported to Paranal where it will undergo testing and commissioning on theVery Large Telescope Interferometer VLTI from the end of 2002through large part of this year 2003. Thereafter it will be available as a user instrument to perform interferometric observations over the8 μm–13 μm wavelength range, with a spatial resolution of typically 20 milliarcsec, a spectral resolution of up to 250, and an anticipated point source sensitivity of N = 3–4 mag or 1–2.5 Jy for self –fringe tracking, which will be the only observing mode during the first months of operation. We describe the layout of the instrument, laboratory tests, and expected performance, both for broadband and spectrally resolved observing modes. We also briefly outline the planned guaranteed time observations. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

The VLTI – A Status Report     

A. Glindemann  J. Algomedo  R. Amestica  P. Ballester  B. Bauvir  E. Bugueño  S. Correia  F. Delgado  F. Delplancke  F. Derie  Ph. Duhoux  E. di Folco  A. Gennai  B. Gilli  P. Giordano  Ph. Gitton  S. Guisard  N. Housen  A. Huxley  P. Kervella  M. Kiekebusch  B. Koehler  S. Lévêque  A. Longinotti  S. Ménardi  S. Morel  F. Paresce  T. Phan Duc  A. Richichi  M. Schöller  M. Tarenghi  A. Wallander  M. Wittkowski  R. Wilhelm 《Astrophysics and Space Science》2003,286(1-2):35-44

The Very Large Telescope (VLT) Observatory on Cerro Paranal (2635 m) in Northern Chile is approaching completion. After the four 8-m Unit Telescopes (UT) individually saw first light in the last years, two of them were combined for the first time on October 30, 2001 to form a stellar interferometer, the VLT Interferometer. The combination in pairs of all four UTs was completed in September 2002. In this article, we will describe the subsystems of the VLTI and the planning for the following years. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献