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See detailA Herschel Study of D/H in Water in the Jupiter-family Comet 45P/Honda-Mrkos-Pajdušáková and Prospects for D/H Measurements with CCAT
Lis, D. C.; Biver, N.; Bockelée-Morvan, D. et al

in Astrophysical Journal Letters (2013), 774

We present Herschel observations of water isotopologues in the atmosphere of the Jupiter-family comet 45P/Honda-Mrkos-Pajdušáková. No HDO emission is detected, with a 3σ upper limit of 2.0 × 10[SUP]–4 ... [more ▼]

We present Herschel observations of water isotopologues in the atmosphere of the Jupiter-family comet 45P/Honda-Mrkos-Pajdušáková. No HDO emission is detected, with a 3σ upper limit of 2.0 × 10[SUP]–4[/SUP] for the D/H ratio. This value is consistent with the earlier Herschel measurement in the Jupiter-family comet 103P/Hartley 2. The canonical value of 3 × 10[SUP]–4[/SUP] measured pre-Herschel in a sample of Oort-cloud comets can be excluded at a 4.5σ level. The observations presented here further confirm that a diversity of D/H ratios exists in the comet population and emphasize the need for additional measurements with future ground-based facilities, such as CCAT, in the post-Herschel era. [less ▲]

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See detailThe Herschel view of nebulae around evolved massive stars
Vamvatira Nakou, Chloi ULg; Royer, P.; Hutsemekers, Damien ULg et al

Conference (2011)

The detailed study of the nebulae ejected from Luminous Blue Variables and the circumstellar bubbles around Wolf-Rayet stars, which radiate strongly in the IR due to the heating of dust, is crucial for ... [more ▼]

The detailed study of the nebulae ejected from Luminous Blue Variables and the circumstellar bubbles around Wolf-Rayet stars, which radiate strongly in the IR due to the heating of dust, is crucial for understanding the massive stars evolution. With Herschel, the largest telescope ever flown in space, we are able to study the gas and the dust in these circumstellar environments in the full far-infrared waveband. In the context of 'Mass-loss of Evolved StarS' Herschel guaranteed time key programme, we have obtained imaging and spectroscopic observations of nebulae associated with Luminous Blue Variable and Wolf-Rayet stars using PACS, one of the three instruments onboard Herschel. A description of these observations and first results of the data analysis are presented. [less ▲]

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See detailHerschel's "Cold Debris Disks": Background Galaxies or Quiescent Rims of Planetary Systems?
Krivov, A. V.; Eiroa, C.; Löhne, T. et al

in Astrophysical Journal (2013), 772

(abridged) Infrared excesses associated with debris disk host stars detected so far peak at wavelengths around ~100{\mu}m or shorter. However, six out of 31 excess sources in the Herschel OTKP DUNES have ... [more ▼]

(abridged) Infrared excesses associated with debris disk host stars detected so far peak at wavelengths around ~100{\mu}m or shorter. However, six out of 31 excess sources in the Herschel OTKP DUNES have been seen to show significant - and in some cases extended - excess emission at 160{\mu}m, which is larger than the 100{\mu}m excess. This excess emission has been suggested to stem from debris disks colder than those known previously. Using several methods, we re-consider whether some or even all of the candidates may be associated with unrelated galactic or extragalactic emission and conclude that it is highly unlikely that none of the candidates represents a true circumstellar disk. For true disks, both the dust temperatures inferred from the SEDs and the disk radii estimated from the images suggest that the dust is nearly as cold as a blackbody. This requires the grains to be larger than ~100{\mu}m, regardless of their material composition. To explain the dearth of small grains, we explore several conceivable scenarios: transport-dominated disks, disks of low dynamical excitation, and disks of unstirred primordial macroscopic grains. Our qualitative analysis and collisional simulations rule out the first two of these scenarios, but show the feasibility of the third one. We show that such disks can survive for gigayears, largely preserving the primordial size distribution. They should be composed of macroscopic solids larger than millimeters, but smaller than kilometers in size. Thus planetesimal formation, at least in the outer regions of the systems, has stopped before "cometary" or "asteroidal" sizes were reached. [less ▲]

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See detailHerschel-PACS far-infrared photometry of two z > 4 quasars
Leipski, C.; Meisenheimer, K.; Klaas, U. et al

in Astronomy and Astrophysics (2010), 518(Letters), 341-4

We present Herschel far-infrared (FIR) observations of two sub-mm bright quasars at high redshift: SDSS J1148+5251 (z = 6.42) and BR 1202-0725 (z = 4.69) obtained with the PACS instrument. Both objects ... [more ▼]

We present Herschel far-infrared (FIR) observations of two sub-mm bright quasars at high redshift: SDSS J1148+5251 (z = 6.42) and BR 1202-0725 (z = 4.69) obtained with the PACS instrument. Both objects are detected in the PACS photometric bands. The Herschel measurements provide additional data points that constrain the FIR spectral energy distributions (SEDs) of both sources, and they emphasise a broad range of dust temperatures in these objects. For λ[SUB]rest[/SUB] ≲ 20 μm, the two SEDs are very similar to the average SEDs of quasars at low redshift. In the FIR, however, both quasars show excess emission compared to low-z QSO templates, most likely from cold dust powered by vigorous star formation in the QSO host galaxies. For SDSS J1148+5251 we detect another object at 160 μm with a distance of ~10´´ from the QSO. Although no physical connection between the quasar and this object can be shown with the available data, it could potentially confuse low-resolution measurements, thus resulting in an overestimate of the FIR luminosity of the z = 6.42 quasar. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA. [less ▲]

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See detailThe Herschel-PACS Grating Drive and its controller
Renotte, Etienne ULg; Callut, Eric ULg; Guiot, Marc ULg et al

(2003)

The Photodetector Array Camera and Spectrometer (PACS), on board the Herschel Space Observatory, is designed for imaging and spectroscopy in the wavelength region between 60 and 210 gm. This paper reports ... [more ▼]

The Photodetector Array Camera and Spectrometer (PACS), on board the Herschel Space Observatory, is designed for imaging and spectroscopy in the wavelength region between 60 and 210 gm. This paper reports the design of the grating cryogenic mechanism of the PACS spectrometer and its remote controller (DEC/MEC) located on the outside of the Herschel cryostat. The PACS grating shall be capable of accurate positioning (4 arcsec) within a large angular stroke (40 arcdeg) in cryogenic environment (4.2 K). Technologies of actuators, position sensors, pivots, dry lubricants, servo-control and cryogenic test set-up are presented. At the other end of the Herschel 10-meter high-impedance cryogenic harness, the DEC/MEC consists of DSP processor-based electronics that control and synchronise the cold focal plane mechanisms and infrared detector arrays. The DEC/MEC operates an on board software running under a real-time operating system. Technologies involved in the control electronics are discussed and correlated to validation tests conducted with actual hardwares. [less ▲]

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See detailHerschel-PACS observations of Nebulae Ejected by Massive Stars
Vamvatira Nakou, Chloi ULg; Royer, Pierre; Hutsemekers, Damien ULg et al

in Bulletin de la Société Royale des Sciences de Liège (2011), 80

The study of the nebulae ejected from Luminous Blue Variables and the circumstellar bubbles around Wolf-Rayet stars, which radiate strongly in the infrared due to the heating of dust, is crucial for the ... [more ▼]

The study of the nebulae ejected from Luminous Blue Variables and the circumstellar bubbles around Wolf-Rayet stars, which radiate strongly in the infrared due to the heating of dust, is crucial for the understanding of the massive stars evolution. With Herschel we are able to observe these objects in the far-infrared region. In the context of the Mass-loss from Evolved StarS guaranteed time key program, we obtained imaging and spectroscopic observations of nebulae associated with Luminous Blue Variable and Wolf-Rayet stars using PACS, one of the three instruments on-board Herschel. A description of these observations, data analysis and preliminary results are presented. [less ▲]

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See detailThe Herschel-SPIRE submillimetre spectrum of Mars
Swinyard, B. M.; Hartogh, P.; Sidher, S. et al

in Astronomy and Astrophysics (2010), 518

We have obtained the first continuous disk averaged spectrum of Mars from 450 to 1550 Ghz using the Herschel-SPIRE Fourier-transform spectrometer. The spectrum was obtained at a constant resolution of 1.4 ... [more ▼]

We have obtained the first continuous disk averaged spectrum of Mars from 450 to 1550 Ghz using the Herschel-SPIRE Fourier-transform spectrometer. The spectrum was obtained at a constant resolution of 1.4 GHz across the whole band. The flux from the planet is such that the instrument was operated in “bright source” mode to prevent saturation of the detectors. This was the first successful use of this mode and in this work we describe the method used for observing Mars together with a detailed discussion of the data reduction techniques required to calibrate the spectrum. We discuss the calibration accuracy obtained and describe the first comparison with surface and atmospheric models. In addition to a direct photometric measurement of the planet the spectrum contains the characteristic transitions of [SUP]12[/SUP]CO from J 5-4 to J 13-12 as well as numerous H[SUB]2[/SUB]O transitions. Together these allow the comparison to global atmospheric models allowing the mean mixing ratios of water and [SUP]12[/SUP]CO to be investigated. We find that it is possible to match the observed depth of the absorption features in the spectrum with a fixed water mixing ratio of 1×10[SUP]-4[/SUP] and a [SUP]12[/SUP]CO mixing ratio of 9×10[SUP]-4[/SUP]. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA. [less ▲]

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See detailHerschel/HIFI observations of Mars: First detection of O2 at submillimetre wavelengths and upper limits on HCl and H2O2
Hartogh, P.; Jarchow, C.; Lellouch, E. et al

in Astronomy and Astrophysics (2010), 521

We report on an initial analysis of Herschel/HIFI observations of hydrogen chloride (HCl), hydrogen peroxide (H[SUB]2[/SUB]O[SUB]2[/SUB]), and molecular oxygen (O[SUB]2[/SUB]) in the Martian atmosphere ... [more ▼]

We report on an initial analysis of Herschel/HIFI observations of hydrogen chloride (HCl), hydrogen peroxide (H[SUB]2[/SUB]O[SUB]2[/SUB]), and molecular oxygen (O[SUB]2[/SUB]) in the Martian atmosphere performed on 13 and 16 April 2010 (L[SUB]s[/SUB] ~ 77°). We derived a constant volume mixing ratio of 1400 ± 120 ppm for O[SUB]2[/SUB] and determined upper limits of 200 ppt for HCl and 2 ppb for H[SUB]2[/SUB]O[SUB]2[/SUB]. Radiative transfer model calculations indicate that the vertical profile of O[SUB]2[/SUB] may not be constant. Photochemical models determine the lowest values of H[SUB]2[/SUB]O[SUB]2[/SUB] to be around L[SUB]s[/SUB] ~ 75° but overestimate the volume mixing ratio compared to our measurements. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA. [less ▲]

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See detailHersemantisering in het Nederlandse genussysteem
De Vos, Lien ULg

in Studies van de BKL (2008), 3

The gender system of the northern variety of Dutch has a long and well-known history of development. These developments seemingly have led to a divergence between the northern and the southern gender ... [more ▼]

The gender system of the northern variety of Dutch has a long and well-known history of development. These developments seemingly have led to a divergence between the northern and the southern gender system, the latter one being a more conservative system, retaining the original three genders. Regarding pronominal gender, recent studies have indicated that the northern varieties make use of some semantic properties of the referent, in order to choose the appropriate pronoun. In the southern varieties there is still syntactic agreement: the choice of the pronoun is based upon the grammatical gender of the noun, rather than on the conceptual properties of its referent. This article investigates the extent to which southern speakers use grammatical gender, in order to clarify the current situation of the pronominal gender system in southern Dutch. As the results will show, the southern pronominal gender system has started developing to a semantic system, so that the distance between the gender systems of both varieties of Dutch will decrease. [less ▲]

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See detailHerstellung von neuen strahlenhärtbarenden Bindemitteln
Weikard, Jan; Greszta-Franz, Dorota; Fischer, Wolfgang et al

Patent (2006)

A binder is prepared by reacting isocyanate-functional compound(s) containing uretdione groups; compounds that contain isocyanate-reactive groups and contain groups that react with ethylenically ... [more ▼]

A binder is prepared by reacting isocyanate-functional compound(s) containing uretdione groups; compounds that contain isocyanate-reactive groups and contain groups that react with ethylenically unsaturated compounds; saturated, hydroxyl-containing compound(s); and a catalyst containing ammonium salts or phosphonium salts of aliphatic or cycloaliphatic carboxylic acids. Preparation of a binder containing allophanate groups, groups that react with ethylenically unsaturated compounds with polymerization on exposure to actinic radiation (radiation-curing groups), and optionally isocyanate (NCO)-reactive groups, which comprises reacting at 130[deg]C NCO-functional compound(s) containing uretdione groups; compounds that contain isocyanate-reactive groups and contain groups that react with ethylenically unsaturated compounds with polymerization on exposure to actinic radiation (radiation-curing groups); saturated, hydroxyl-containing compound(s), at least one of these compounds having an OH functionality of 2; and a catalyst containing one or more ammonium salts or phosphonium salts of aliphatic or cycloaliphatic carboxylic acids, the reaction hydroxyl-containing compounds taking place at least proportionally with the formation of allophanate groups. An independent claim is also included for a coating composition comprising: (1) binders; (2) optionally polyisocyanate(s) which contain free or blocked isocyanate groups and optionally contain groups which react with ethylenically unsaturated compounds with polymerization on exposure to actinic radiation; (3) optionally compounds other than the polyisocyanate(s) which contain groups which react with ethylenically unsaturated compounds with polymerization on exposure to actinic radiation and optionally contain NCO-reactive groups; (4) optionally isocyanate-reactive compound(s) which are free from groups which react with ethylenically unsaturated compounds with polymerization on exposure to actinic radiation; and (5) initiators. [less ▲]

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See detailHerstellung von neuen strahlenhärtenden bindemitteln
Detrembleur, Christophe ULg; Weikard, Jan; Greszta-Franz, Dorota et al

Patent (2009)

Die vorliegende Erfindung betrifft ein Verfahren zur Herstellung neuartiger Bindemittel, die unter Einwirkung aktinischer Strahlung mit ethylenisch ungesättigten Verbindungen unter Polymerisation ... [more ▼]

Die vorliegende Erfindung betrifft ein Verfahren zur Herstellung neuartiger Bindemittel, die unter Einwirkung aktinischer Strahlung mit ethylenisch ungesättigten Verbindungen unter Polymerisation reagierende Gruppen und gegebenenfalls auch gegenüber Isocyanaten reaktive Gruppen aufweisen, sowie deren Verwendung in Beschichtungsmitteln. [less ▲]

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See detailHerstellung von neuen strahlenhärtenden bindemitteln
Detrembleur, Christophe ULg; Weikard, Jan; Greszta-Franz, Dorota et al

Patent (2009)

Die vorliegende Erfindung betrifft ein Verfahren zur Herstellung neuartiger Bindemittel, die unter Einwirkung aktinischer Strahlung mit ethylenisch ungesättigten Verbindungen unter Polymerisation ... [more ▼]

Die vorliegende Erfindung betrifft ein Verfahren zur Herstellung neuartiger Bindemittel, die unter Einwirkung aktinischer Strahlung mit ethylenisch ungesättigten Verbindungen unter Polymerisation reagierende Gruppen und gegebenenfalls auch gegenüber Isocyanaten reaktive Gruppen aufweisen, sowie deren Verwendung in Beschichtungsmitteln. [less ▲]

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See detailHerstellung von neuen strahlenhärtenden Bindemitteln
Detrembleur, Christophe ULg; Weikard, Jan; Greszta-Frank, Dorota et al

Patent (2007)

Die vorliegende Erfindung betrifft ein Verfahren zur Herstellung neuartiger Bindemittel, die unter Einwirkung aktinischer Strahlung mit ethylenisch ungesättigten Verbindungen unter Polymerisation ... [more ▼]

Die vorliegende Erfindung betrifft ein Verfahren zur Herstellung neuartiger Bindemittel, die unter Einwirkung aktinischer Strahlung mit ethylenisch ungesättigten Verbindungen unter Polymerisation reagierende Gruppen und gegebenenfalls auch gegenüber Isocyanaten reaktive Gruppen aufweisen, sowie deren Verwendung in Beschichtungsmitteln. [less ▲]

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See detailHerstellung von neuen strahlenhärtenden bindemitteln
Detrembleur, Christophe ULg; Weikard, Jan; Greszta-Franz, Dorota et al

Patent (2009)

Die vorliegende Erfindung betrifft ein Verfahren zur Herstellung neuartiger Bindemittel, die unter Einwirkung aktinischer Strahlung mit ethylenisch ungesättigten Verbindungen unter Polymerisation ... [more ▼]

Die vorliegende Erfindung betrifft ein Verfahren zur Herstellung neuartiger Bindemittel, die unter Einwirkung aktinischer Strahlung mit ethylenisch ungesättigten Verbindungen unter Polymerisation reagierende Gruppen und gegebenenfalls auch gegenüber Isocyanaten reaktive Gruppen aufweisen, sowie deren Verwendung in Beschichtungsmitteln. [less ▲]

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See detailHerstellung von neuen strahlenhärtenden bindemitteln
Detrembleur, Christophe ULg; Weikard, Jan; Greszta-Franz, Dorota et al

Patent (2005)

Die vorliegende Erfindung betrifft ein Verfahren zur Herstellung neuartiger Bindemittel, die unter Einwirkung aktinischer Strahlung mit ethylenisch ungesättigten Verbindungen unter Polymerisation ... [more ▼]

Die vorliegende Erfindung betrifft ein Verfahren zur Herstellung neuartiger Bindemittel, die unter Einwirkung aktinischer Strahlung mit ethylenisch ungesättigten Verbindungen unter Polymerisation reagierende Gruppen und gegebenenfalls auch gegenüber Isocyanaten reaktive Gruppen aufweisen, sowie deren Verwendung in Beschichtungsmitteln. [less ▲]

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See detailHerstelrecht - Restorative Justice
Lauwaert, Katrien ULg

Scientific conference (2009, September 30)

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See detailHerstelrecht - Restorative Justice
Lauwaert, Katrien ULg

Scientific conference (2011, September 16)

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See detailHerstelrecht en de rechtsstaat
Lauwaert, Katrien ULg; Aertsen, Ivo; Kool, Renée

in Tijdschrift voor Herstelrecht (2004), (3), 7-10

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