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See detailObservations of significant flux closure by dual lobe reconnection
Imber, S. M.; Milan, S. E.; Hubert, Benoît ULg

in Annales Geophysicae (2007), 25(7), 1617-1627

We present an interval of dual lobe reconnection during which interplanetary magnetic field lines are captured by the magnetosphere by reconnecting at high latitudes in both the Northern and the Southern ... [more ▼]

We present an interval of dual lobe reconnection during which interplanetary magnetic field lines are captured by the magnetosphere by reconnecting at high latitudes in both the Northern and the Southern Hemispheres. This event was identified using measurements of the ionospheric convection flow and observations of the aurora using the Super-DARN radars and the IMAGE spacecraft. A cusp spot, characteristic of northward IMF, is clearly visible for a 30 min period enabling the ionospheric footprint of the Northern Hemisphere merging gap to be accurately determined. During the interval a strong burst of sunward flow across the dayside open/closed field line boundary (OCB) is observed, which we interpret as the reconfiguration of the magnetosphere following a burst of reconnection. Noon-midnight and dawn-dusk keograms of the aurora show that the polar cap shrinks during the interval indicating that a large amount of flux was closed by the reconnection. Using the SuperDARN potential maps it is possible to calculate that the amount of flux closed during the interval is 0.13 GWb which represents approximately 10% of the pre-existing polar cap. The number of ions captured by the burst of dual lobe reconnection was calculated to be similar to 2.2x10(31), more than sufficient to populate a cold, dense plasma sheet. That a dense plasma sheet was not subsequently observed is discussed in terms of subsequent changes in the IMF. [less ▲]

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See detailObservations of southern nebulae
Danks, A. C.; Houziaux, Léo ULg; Manfroid, Jean ULg

in Astrophysics & Space Science (1976), 39

Spectroscopic observations of 10 H II regions in the southern hemisphere are presented. The observations cover the spectral region 3600-8000 A.

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See detailObservations of substorm auroras from the IMAGE spacecraft
Frey, H. U.; Mende, S. B.; Lampton, M. et al

Conference (2000, October)

See detailObservations of the H and H[SUB]2[/SUB] Ultraviolet Jovian Aurora with the HST Faint Object Camera
Gérard, Jean-Claude ULg; Dols, V.; Paresce, F. et al

in Bulletin of the American Astronomical Society (1992, June 01)

Not Available

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See detailObservations of the Jovian low latitude FUV emission with HST/STIS
Gustin, Jacques ULg; Grodent, Denis ULg; Dols, V. et al

Poster (1999, October 10)

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See detailObservations of the Jovian System with the Chandra X-ray Observatory
Elsner, R. F.; Gladstone, G. R.; Lewis, W. S. et al

Conference (2002)

Sensitive, very high spatial-resolution x-ray observations with the Chandra X-ray Observatory have revealed that Jupiter's northern x-ray aurora originates at a spot fixed in a coordinate system rotating ... [more ▼]

Sensitive, very high spatial-resolution x-ray observations with the Chandra X-ray Observatory have revealed that Jupiter's northern x-ray aurora originates at a spot fixed in a coordinate system rotating with the planet at latitude (60-70 deg north) and longitude (160-180 deg System III). The northern auroral x-ray emission varies with a period about 45 minute and has an average power of about 1 GW. Jupiter's disk also emits x-rays with a power of about 2 GW, perhaps resulting from reprocessing of solar x-rays in its atmosphere. These observations reveal for the first time x-ray emission from the Io Plasma Torus, with a power of about 0.1 GW. Finally, we report the discovery of very faint (about 1-2 MW) soft x-ray emission from the Galilean satellites Io, Europa, and probably Ganymede. [less ▲]

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See detailObservations of the new gravitational lens system UM 673 = Q 0142-100
Surdej, Jean ULg; Magain, Pierre ULg; Swings, J.-P. et al

in Astronomy and Astrophysics (1988), 198

The authors have recently initiated a high resolution direct imaging survey of a selected sample of highly luminous quasars (HLQs). The observations are carried out with the 2.2 m telescope at ESO, and ... [more ▼]

The authors have recently initiated a high resolution direct imaging survey of a selected sample of highly luminous quasars (HLQs). The observations are carried out with the 2.2 m telescope at ESO, and with the VLA at the NRAO, New Mexico. Following the first observing run at ESO, the authors have reported the discovery of a new gravitational lens system for the HLQ UM 673 = Q 0142-100. Additional observations supporting this interpretation are discussed here. Application of gravitational optometry to this system is given: a value of M[SUB]0[/SUB] = 2.4×10[SUP]11[/SUP]M_sun; is derived for the mass of the lensing galaxy located between UM 673 A and B and a most likely estimate of Deltat = 7 weeks is found for the expected delay between the arrival times of a similar variability event in the two lensed images of the quasar (H[SUB]0[/SUB] = 75 km s[SUP]-1[/SUP]Mpc[SUP]-1[/SUP], q[SUB]0[/SUB] = 0). [less ▲]

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See detailObservations of the reduction of external gill filaments during larval development in Heterotis niloticus
Hermens, Michaël; Daffé, Mamina; Vandewalle, Pierre ULg

in Belgian Journal of Zoology (2007), 137(2), 247-249

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See detailObservations of the rotational lines of OH in comets with the Herschel Space Observatory
Crovisier, J.; Bockelée-Morvan, D.; Biver, N. et al

in EPSC Abstracts 2011 (2011)

We present here a search for the OH rotational lines in these spectral scans. In comet 103P/Hartley 2, the 2 3/2(5/2)-2 3/2(3/2) lines at 119 μm and 2 1/2(5/2)-2 1/2(3/2) lines at 99 μm are detected ... [more ▼]

We present here a search for the OH rotational lines in these spectral scans. In comet 103P/Hartley 2, the 2 3/2(5/2)-2 3/2(3/2) lines at 119 μm and 2 1/2(5/2)-2 1/2(3/2) lines at 99 μm are detected. Other lines may be marginally present. Two mechanisms concur to the emission of the OH rotational lines: fluorescence due to solar excitation of the electronic states of OH [8] and prompt emission following the photodissociation of water, which produces the OH radical in electronic, vibrational and rotational excited states [9, 10]. We will compare the observed line intensities with those expected from these mechanisms, using the comet water productions determined from Herschel [6, 7], in order to better constrain the excitation of cometary OH. [less ▲]

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See detailObservations of the White Light Corona from Solar Orbiter and Solar Probe Plus
Howard, Russell; Thernisien, Arnaud; Vourlidas, Angelos et al

Conference (2011, December 08)

The SoloHI instrument on Solar Orbiter and the WISPR instrument on Solar Probe+ will make white light coronagraphic images of the corona as the two spacecraft orbit the Sun. The minimum perihelia for ... [more ▼]

The SoloHI instrument on Solar Orbiter and the WISPR instrument on Solar Probe+ will make white light coronagraphic images of the corona as the two spacecraft orbit the Sun. The minimum perihelia for Solar Orbiter is about 60 Rsun and for SP+ is 9.5 Rsun. The wide field of view of the WISPR instrument (about 105 degrees radially) corresponds to viewing the corona from 2.2 Rsun to 20 Rsun. Thus the entire Thomson hemisphere is contained within the telescope’s field and we need to think of the instrument as being a traditional remote sensing instrument and then transitioning to a local in-situ instrument. The local behavior derives from the fact that the maximum Thomson scattering will favor the electron plasma close to the spacecraft - exactly what the in-situ instruments will be sampling. SoloHI and WISPR will also observe scattered light from dust in the inner heliosphere, which will be an entirely new spatial regime for dust observations from a coronagraph, which we assume to arise from dust in the general neighborhood of about half way between the observer and the Sun. As the dust grains approach the Sun, they evaporate and do not contribute to the scattering. A dust free zone has been postulated to exist somewhere inside of 5 Rsun where all dust is evaporated, but this has never been observed. The radial position where the evaporation occurs will depend on the precise molecular composition of the individual grains. The orbital plane of Solar Orbiter will gradually increase up to about 35 degrees, enabling a very different view through the zodiacal dust cloud to test the models generated from in-ecliptic observations. In this paper we will explore some of the issues associated with the observation of the dust and will present a simple model to explore the sensitivity of the instrument to observe such evaporations. [less ▲]

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See detailObservations on detection, excretion and transmission of pigeon circovirus in adult, young and embryonic pigeons
Duchatel, Jean-Pierre ULg; Todd D; Smyth J et al

in Avian Pathology : Journal of the W.V.P.A (2006), 35

Infections with pigeon circovirus (PiCV) occur in young racing pigeons and pigeons raised for meat production and have been reported worldwide, but relatively little is known about the disease induced by ... [more ▼]

Infections with pigeon circovirus (PiCV) occur in young racing pigeons and pigeons raised for meat production and have been reported worldwide, but relatively little is known about the disease induced by PiCV infection. The aim of this study was to investigate how PiCV is transmitted. Using a sensitive polymerase chain reaction (PCR) test, the presence of PiCV was investigated in a wide range of samples from adult pigeons, embryos, breeders and young birds, which were derived from a racing loft that had a clinical history of ‘‘young pigeon sickness’’ and in which PiCV had been previously been diagnosed. Using PCR, PiCV DNA was detected in tissues of 13/20 apparently healthy older birds, aged from 1 to 9 years. Viral DNA was most commonly detected in the respiratory organs, including the trachea, pharynx and lung, followed by tissues such as the spleen, kidney and liver. It was also detected in the ovary and/or testes of some birds. This finding, and the detection of viral DNA in tissues from 8/22 embryos, suggested that PiCV may be vertically transmitted. Testing of pharyngeal and cloacal swabs, and blood samples, collected immediately before the death of the adult pigeons, failed to detect all birds found to be infected at necropsy, suggesting that testing of potential breeding birds would not enable exclusion of infected birds from breeding programmes. Additional PCR testing of cloacal swab samples obtained sequentially from 19 young pigeons showed that while four were excreting virus when 15 days old, only one bird was excreting at the time of weaning (28 days old). The detection of viral DNA in cloacal swab samples from 15.8% of the birds when 37 days old and 100% of birds when 51 days old suggested that most young pigeons probably became infected in the rearing loft. [less ▲]

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See detailObservations on seed protein electrophoretic patterns of some species within the genus Phaseolus.
Baudoin, Jean-Pierre ULg; Schmit, V.; Wathelet, Bernard ULg

in Annual Report of the Bean Improvment Cooperative (1991), 34

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See detailObservations on the establishment of a Devonian and Lower Carboniferous high resolution miospore biostratigraphy
Streel, Maurice ULg; Loboziak, S

in Review of Palaeobotany and Palynology (1994), 83

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See detailObservations on the Helminths of Harbour Porpoises (Phocoena Phocoena) and Common Guillemots (Uria Aalge) from the Belgian and German Coasts
Brosens, L.; Jauniaux, Thierry ULg; Siebert, U. et al

in Veterinary Record : Journal of the British Veterinary Association (1996), 139(11), 254-7

Between February 1990 and July 1991, 18 harbour porpoises (Phocoena phocoena) and 248 common guillemots (Uria aalge), found dead along the Belgian and German coasts, were examined for their burden of ... [more ▼]

Between February 1990 and July 1991, 18 harbour porpoises (Phocoena phocoena) and 248 common guillemots (Uria aalge), found dead along the Belgian and German coasts, were examined for their burden of helminths. A total of three species were found in the guillemots (one cestode, one nematode and one pentastomid), and six species in the porpoises (one trematode, one cestode and four nematodes). Among the guillemots the burden of helminths was not statistically different between juvenile and adult birds. The deaths of the birds were apparently not related to the parasite infections. In contrast, the adult porpoises were more heavily parasitised than the juveniles, except for one young porpoise stranded on the Belgian coast. In the porpoises, four species of parasites had a pathological effect and Torynurus convolutus was responsible for the death of one animal from the Belgian coast and three from the German coast. [less ▲]

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See detailObservations on the mites (Acarai) associated with Carabidae (Coleoptera) in Belgium.
Fain, A.; Noti, J.; Dufrêne, Marc ULg

in International Journal of Acarology (1995), 21

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See detailObservations on the Relative Intactness of the Mesolithic Strata at l'Abri du Pape
Miller, Rebecca ULg; Straus, Lawrence G.

in Otte, Marcel; Léotard, Jean-Marc; Straus, Lawrence G. (Eds.) L'Abri du Pape : Bivouacs, enterrements et cachettes sur la Haute Meuse belge : du Mésolithique au Bas Empire Roman (1999)

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See detailObservations palynologiques dans le Couvinien (Emsien terminal et Eifélien) du bord oriental du Synclinorium de Dinant, Belgique.
Lessuise, A; Streel, Maurice ULg; Vanguestaine, M

in Annales de la Société Géologique de Belgique (1979), 102

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See detailObservations photographiques de la comète Kohoutek (1973 f) au grand télescope de Schmidt franco-liégeois
Dossin, P.; Heck, A.; Klutz, M. et al

in Ciel et Terre (1974), 90

Not Available

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See detailObservations photographiques de la comète P/d'Arrest effectuées en 1976 à l'équatorial GPO de 40 cm de l'Observatoire Austral Européen (ESO) à La Silla (Chili).
Debehogne, H.; Surdej, Jean ULg; Surdej, Anna ULg

in Bulletin de l'Observatoire Royal Astronomique de Belgique (1978), 9

Not Available

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