FIRST radio counterpart candidates to ULXs: a catalogue     

D. Pérez-Ramírez  J. R. Sánchez-Sutil  A. Muñoz-Arjonilla  J. Martí  J. L. Garrido  P. Luque-Escamilla 《Astrophysics and Space Science》2007,309(1-4):147-150

Ultraluminous X-ray sources (ULXs) are the most luminous discrete X-ray sources (excluding AGNs) in the local Universe with observed luminosities above, and in many cases in excess of, 10³⁹ erg?s^?1. Their physical nature is still uncertain, and many models have been proposed to explain their unusual luminosities. Some of them favour the possible nature of these objects as extragalactic microquasars with strong beaming effects. Others, instead, rely on accretion onto intermediate-mass black holes. In any case, both interpretations offer perspectives for possible gamma-ray detections by future space missions. In order to help to constrain at present the ULX physical nature, we provide here an account of our search for radio counterparts to ULXs located in nearby galaxies, based on a systematic cross-identification of the most recent, available and extensive ULX catalogues and radio archival data. Although we ended up with 70 positional coincidences, most of them were located within the nuclear regions of these galaxies, and thus, they do not represent true ULXs. However, among these sources we identify 11 remarkable cases not previously reported of ULX and radio emission coincidence. Future follow up of these promising cases with a multi-wavelength approach could be useful to improve our understanding of the ULX phenomenon.  相似文献   

Time-dependent convection seismic study of five γ Doradus stars     

M.-A. Dupret  A. Grigahcène  R. Garrido  J. De Ridder  R. Scuflaire  M. Gabriel 《Monthly notices of the Royal Astronomical Society》2005,360(3):1143-1152

We apply for the first time the time-dependent convection (TDC) treatment of Gabriel and Grigahcène et al. to the photometric mode identification in γ Doradus (γ Dor) stars. We consider the influence of this treatment on the theoretical amplitude ratios and phase differences. Comparison with the observed amplitudes and phases of the stars γ Dor, 9 Aurigae, HD 207223 = HR 8330, HD 12901 and 48501 is presented and enables us to identify the degree ℓ of the pulsation modes for four of them. We also determine the mode stability for different models of these stars. We show that our TDC models agree better with observations than with frozen convection models. Finally, we compare the results obtained with different values of the mixing-length parameter α.  相似文献   

δ Sct-type pulsations in eclipsing binary systems: RZ Cas     

E. Rodríguez  J. M. García  D. E. Mkrtichian  V. Costa  S.-L. Kim  M. J. López-González  E. Hintz  A. V. Kusakin  A. Y. Gamarova  J. W. Lee  J.-H. Youn  E. B. Janiashvili  R. Garrido  A. Moya  Y. W. Kang 《Monthly notices of the Royal Astronomical Society》2004,347(4):1317-1326

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GHASP: an Hα kinematic survey of spiral and irregular galaxies – IV. 44 new velocity fields. Extension, shape and asymmetry of Hα rotation curves     

O. Garrido  M. Marcelin  P. Amram  C. Balkowski  J. L. Gach  J. Boulesteix 《Monthly notices of the Royal Astronomical Society》2005,362(1):127-166

We present Fabry–Perot observations obtained in the frame of the GHASP survey (Gassendi HAlpha survey of SPirals). We have derived the Hα map, the velocity field and the rotation curve for a new set of 44 galaxies. The data presented in this paper are combined with the data published in the three previous papers providing a total number of 85 of the 96 galaxies observed up to now. This sample of kinematical data has been divided into two groups: isolated (ISO) and softly interacting (SOFT) galaxies. In this paper, the extension of the Hα discs, the shape of the rotation curves, the kinematical asymmetry and the Tully–Fisher relation have been investigated for both ISO and SOFT galaxies. The Hα extension is roughly proportional to R₂₅ for ISO as well as for SOFT galaxies. The smallest extensions of the ionized disc are found for ISO galaxies. The inner slope of the rotation curves is found to be correlated with the central concentration of light more clearly than with the type or the kinematical asymmetry, for ISO as well as for SOFT galaxies. The outer slope of the rotation curves increases with the type and with the kinematical asymmetry for ISO galaxies but shows no special trend for SOFT galaxies. No decreasing rotation curve is found for SOFT galaxies. The asymmetry of the rotation curves is correlated with the morphological type, the luminosity, the  ( B − V )  colour and the maximal rotational velocity of galaxies. Our results show that the brightest, the most massive and the reddest galaxies, which are fast rotators, are the least asymmetric, meaning that they are the most efficient with which to average the mass distribution on the whole disc. Asymmetry in the rotation curves seems to be linked with local star formation, betraying disturbances of the gravitational potential. The Tully–Fisher relation has a smaller slope for ISO than for SOFT galaxies.  相似文献   

Effects of industrial by-product amendments on As,Cd and Tl retention/release in an element-spiked acidic soil     

Javier Aguilar-Carrillo  Laura Barrios  Fernando Garrido  María Teresa García-González 《Applied Geochemistry》2007

To asses the efficiency of two by-products (phosphogypsum (PG) and sugar foam (SF), rich in gypsum and calcium carbonate, respectively) in the immobilization of three toxic elements (As, Cd and Tl) in an acidic soil, batch-scale sorption and desorption experiments were conducted after 18 months of in situ amendment application. The Langmuir isotherms applied for sorption studies showed that the estimated maximum sorption capacity of the elements was highest in the SF-treated samples. The amount of element retained and the percentage of extraction after TCLP tests indicated that those samples amended with sugar foam (SF and PG + SF) had the potential to immobilize As, Cd and Tl in an acidic soil with low sorptive capacity. In addition to sorption and desorption experiments, scanning electron microscopy in back-scattered electron mode (SEM-BSE) showed the formation of Al-hydroxy polymers which provides the soil with additional sorption capacity. The three target elements were associated with the Al-hydroxy polymers, probably through direct coordination or the formation of ternary complexes. By means of statistical analysis it has been found that sorption processes of As, Cd and Tl in this soil mainly depend on the treatment, whereas desorption is an element-dependent process.  相似文献   

Strain localisation in the subcontinental mantle — a ductile alternative to the brittle mantle     

J. Precigout  F. Gueydan  D. Gapais  C.J. Garrido  A. Essaifi 《Tectonophysics》2007,445(3-4):318-336

It is now admitted that the high strength of the subcontinental uppermost mantle controls the first order strength of the lithosphere. An incipient narrow continental rift therefore requires an important weakening in the subcontinental mantle to promote lithosphere-scale strain localisation and subsequent continental break-up. Based on the classical rheological layering of the continental lithosphere, the origin of a lithospheric mantle shear/fault zone has been attributed to the existence of a brittle uppermost mantle. However, the lack of mantle earthquakes and the absence of field occurrences in the mantle fault zone led to the idea of a ductile-related weakening mechanism, instead of brittle-related, for the incipient mantle strain localisation. In order to provide evidence for this mechanism, we investigated the microstructures and lattice preferred orientations of mantle rocks in a kilometre-scale ductile strain gradient in the Ronda Peridotites (Betics cordillera, Spain). Two main features were shown: 1) grain size reduction by dynamic recrystallisation is found to be the only relevant weakening mechanism responsible for strain localisation and 2), with increasing strain, grain size reduction is coeval with both the scattering of orthopyroxene neoblasts and the decrease of the olivine fabric strength (LPO). These features allow us to propose that grain boundary sliding (GBS) partly accommodates dynamic recrystallisation and subsequent grain size reduction.A new GBS-related experimental deformation mechanism, called dry-GBS creep, has been shown to accommodate grain size reduction during dynamic recrystallisation and to induce significant weakening at low temperatures (T < 800 °C). The present microstructural study demonstrates the occurrence of the grain size sensitive dry-GBS creep in natural continental peridotites and allows us to propose a new rheological model for the subcontinental mantle. During dynamic recrystallisation, the accommodation of grain size reduction by three competing deformation mechanisms, i.e., dislocation, diffusion and dry-GBS creeps, involves a grain size reduction controlled by the sole dislocation creep at high temperatures (> 800 °C), whereas dislocation creep and dry-GBS creep, are the accommodating mechanisms at low temperatures (< 800 °C). Consequently, weakening is very limited if the grain size reduction occurs at temperatures higher than 800 °C, whereas a large weakening is expected in lower temperatures. This large weakening related to GBS creep would occur at depths lower than 60 km and therefore provides an explanation for ductile strain localisation in the uppermost continental mantle, thus providing an alternative to the brittle mantle.  相似文献   

Interplay of State and Local Concern in the Management of Natural Resources: Hydraulics and Forestry in Spain (1855–1936)     

Josefina Gómez Mendoza Dr.  Nicolás Ortega Cantero Dr. 《GeoJournal》1992,26(2):173-179

The modern tradition in the management of nature in Spain was shaped by different policies for economic and social restoration included in a vast plural reformist movement known as Regeneracionismo. The aim of the restoration of wealth was felt to require the correction of the defects of the geographical configuration of the country, and particularly the imbalances in its climatic and hydraulic régimes which derive from its orography. The objective put forward was then to put in place a national hydraulic artery system in order to increase irrigated areas and to redistribute water. Hydraulic policy was to find additional and essential support in hydrological-forestry action.Both hydraulic and forestry policies during the period 1855–1936 are studied in this essay. They are first reviewed in the context of conservation of nonrenewable natural resources. They are then considered as an expression of the conflicts between the State administration and local powers and interests. This tension prevented the rational use of the natural resources available — an antagonism which has by no means disappeared.This essay is based on our contribution to the XVIIth International Congress of History of Science, Hamburg, August 1989.  相似文献   

Highly ordered antigorite from Cerro del Almirez HP–HT serpentinites,SE Spain     

J. A. Padrón-Navarta  V. López Sánchez-Vizcaíno  C. J. Garrido  M. T. Gómez-Pugnaire  A. Jabaloy  G. C. Capitani  M. Mellini 《Contributions to Mineralogy and Petrology》2008,156(5):679-688

The Cerro del Almirez ultramafic massif offers an example of high pressure and high temperature antigorite serpentinites. A sharp antigorite-out isograd separates them from Chl-harzburgites, consisting of olivine + enstatite + chlorite. Antigorite is characterized by aluminium contents as high as 4 wt.% Al₂O₃. The microstructural study shows that, prior to the transformation, antigorite is exceptionally ordered and consists of the polysome m = 17. No polysomatic defect occurs in antigorite forming most of the Cerro del Almirez serpentinites. Close to the antigorite-out isograd, limited disorder features may occur, mainly as (001) twins, reaction rims and reduction of m down to 14–15. Here, local recrystallization phenomena lead to sporadic growth of large antigorite and chlorite crystals.  相似文献   

The composition of nanogranitoids in migmatites overlying the Ronda peridotites (Betic Cordillera,S Spain): the anatectic history of a polymetamorphic basement     

Antonio Acosta-Vigil  Amel Barich  Omar Bartoli  Carlos J. Garrido  Bernardo Cesare  Laurent Remusat  Stefano Poli  Caroline Raepsaet 《Contributions to Mineralogy and Petrology》2016,171(3):24

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Petrogenesis of highly depleted peridotites and gabbroic rocks from the Mayarí-Baracoa Ophiolitic Belt (eastern Cuba)   总被引：1，自引：0，他引：1  

Claudio Marchesi  Carlos J. Garrido  Marguerite Godard  Joaquín A. Proenza  Fernando Gervilla  Jesús Blanco-Moreno 《Contributions to Mineralogy and Petrology》2006,151(6):717-736

The Moa-Baracoa and Mayarí-Cristal massifs (eastern Cuba) are two ophiolitic complexes mainly constituted by harzburgite tectonites and minor dunites, cut by gabbroic dykes. The Moa-Baracoa massif exhibits a well developed Moho transition zone and an incomplete crustal section made up of layered gabbros and tectonically emplaced pillow basalts. A plutonic crustal section is absent in the Mayarí-Cristal massif and mantle tectonites are in tectonic contact with arc-related volcanic rocks. Mantle peridotites are very refractory in terms of modal composition, whole rock major element and HREE contents implying that Moa-Baracoa and Mayarí-Cristal harzburgites are residues after high degrees (20–30%) of partial melting. The relative enrichment of Th, Nb, Ta and LREE in peridotites is due to re-equilibration of melting residues with percolating melts. Peridotites lost on average 6 wt% of relative MgO by intense seafloor weathering. REE contents and Mg# of melts in equilibrium with cumulate gabbros from the Moho transition zone and crustal section of the Moa-Baracoa massif coincide with those of the spatially-related pillow basalts. On the other hand, no geochemical relation has been inferred between melt in equilibrium with Mayarí-Cristal segregate and the spatially-related arc volcanics. Our results indicate that the Mayarí-Baracoa Ophiolitic Belt formed at an original back-arc spreading centre. The Moa-Baracoa massif represents a portion of MORB-like lithosphere located nearby a back-arc mid-ocean spreading ridge, and the Mayarí-Cristal massif represents a piece of transitional (MORB to IAT) mantle located closer to the paleo-volcanic arc than Moa-Baracoa.  相似文献