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See detailIsotope shifts and hyperfine structure of the Fe I 372-nm resonance line
Krins, Stéphanie ULiege; Oppel, S.; Huet, Nicolas ULiege et al

in Physical Review. A (2009), 80

We report measurements of the isotope shifts of the 3d64s2 a 5D4 − 3d64s4p z 5Fo 5 Fe I resonance line at 372 nm between all four stable isotopes 54Fe, 56Fe, 57Fe and 58Fe, as well as the complete ... [more ▼]

We report measurements of the isotope shifts of the 3d64s2 a 5D4 − 3d64s4p z 5Fo 5 Fe I resonance line at 372 nm between all four stable isotopes 54Fe, 56Fe, 57Fe and 58Fe, as well as the complete hyperfine structure of that line for 57Fe, the only stable isotope having a non-zero nuclear spin. The field and specific mass shift coefficients of the transition have been derived from the data, as well as the experimental value for the hyperfine structure magnetic dipole coupling constant A of the excited state of the transition in 57Fe : A(3d64s4p z 5Fo 5 ) = 81.69(86) MHz. The measurements were carried out by means of high-resolution Doppler-free laser saturated absorption spectroscopy in a Fe-Ar hollow cathode discharge cell using both natural and enriched iron samples. The measured isotope shifts and hyperfine constants are reported with uncertainties at the percent level. [less ▲]

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See detailIsotope shifts and hyperfine structure of the laser-cooling Fe I 358-nm line
Huet, Nicolas ULiege; Pettens, Manon; Bastin, Thierry ULiege

in Physical Review A (2015), 92

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See detailIsotope splitting of the zero-phonon line of Fe2+ in cubic III-V semiconductors
Colignon, David ULiege; Mailleux, Éric; Kartheuser, Eduard ULiege et al

in Solid State Communications (1998), 105(4), 205-209

A theoretical study of the isotopic-mass dependence of the internal transitions of Fe2+ at a cation site in a cubic zinc-blende semiconductor is presented. The model used is based on crystal-field theory ... [more ▼]

A theoretical study of the isotopic-mass dependence of the internal transitions of Fe2+ at a cation site in a cubic zinc-blende semiconductor is presented. The model used is based on crystal-field theory and includes the spin-orbit interaction and a weak dynamic Jahn-Teller coupling between the (5) Gamma(5) excited manifold of Fe2+ and a local vibrational mode (LVM) of Gamma(5) symmetry. The mass dependence of the LVM frequency is described, in the harmonic approximation, within two different limits: the rigid-cage model and a molecular model. In the rigid-cage model, the Fe2+ ion undergoes a displacement but the rest of the lattice is fixed. In this case, a simple M-1/2 dependence of the frequency is obtained and the Jahn-Teller energy, E-JT, is independent of the mass. In the molecular model, the four nearest neighbors of the magnetic ion are allowed to move and the LVM then behaves as the Gamma(5) mode of a MX4 tetrahedral molecule leading to a more complicated dependence of the frequency on the isotopic mass and to a mass-dependence of E-JT. The theoretical results obtained with these two models are compared with the observed isotopic shifts of the zero-phonon lines in InP:Fe and GaP:Fe corresponding to an optical transition between the vibronic Gamma(1) ground state and the lowest Gamma(5) state originating from the (5) Gamma(5) excited orbital multiplet. A prediction of the isotopic shifts of the zero-phonon line in GaAs:Fe is also presented. (C) 1997 Elsevier Science Ltd. [less ▲]

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See detailL'isotope stable 15N et le lysimètre, des outils complémentaires pour l'étude de la lixiviation de l'azote dans les sols agricoles.
Destain, Jean-Pierre ULiege; Fonder, Nathalie ULiege; Xanthoulis, Dimitri ULiege et al

in Vandenberghe, Christophe; Marcoen, Jean Marie (Eds.) Atelier Nitrate-Eau. Evaluation du Programme de Gestion Durable de l'Azote. (2010)

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See detailL'isotope stable 15Net le lysimètre, des outils complémentaires pour l'étude de la lixiviation de l'azote dans les sols agricoles
Destain, Jean-Pierre ULiege; Fonder, Nathalie; Xanthoulis, Dimitri ULiege et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2010), 14(S1), 91-96

L’isotope stable 15N a été utilisé dans des expérimentations en cases lysimétriques visant à étudier la lixiviation de l’azote dans les sols agricoles. À Gembloux, un apport de nitrate l’ammoniaque ... [more ▼]

L’isotope stable 15N a été utilisé dans des expérimentations en cases lysimétriques visant à étudier la lixiviation de l’azote dans les sols agricoles. À Gembloux, un apport de nitrate l’ammoniaque présentant une abondance isotopique de 2,161 At%15N a été appliqué à raison de 200 kg N.ha-1 dans deux lysimètres, avant une culture d’épinard suivie de haricot et d’un froment d’hiver. La récupération de l’azote par les cultures a été de 39,8 % dans le premier lysimètre et de 62,2 % dans le second. Les concentrations en azote nitrique des eaux percolées du second ont été constamment plus élevées que dans le premier, probablement à cause d’une moindre immobilisation microbienne. À Remicourt et Omal, un reliquat de 150 kg N.ha-1 (simulé par un apport de 15NH4 15NO3 en automne) a complètement disparu du profil du sol (0-90 cm) dès juillet de l’année suivante. Une culture de froment d’hiver à Omal n’a récupéré qu’environ 9 % de l’azote apporté à l’automne. La mesure de la teneur en azote nitrique des eaux percolées a montré des valeurs nettement plus élevées à Remicourt (jusqu’à plus de 70 mg N.l-1) suite à un apport important de compost riche en azote, qu’à Omal. L’isotope 15N n’a pu être détecté dans aucune des eaux lysimétriques, probablement par un manque de sensibilité de l’appareil. [less ▲]

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See detailIsotopic abundance in the CN coma of comets: Ten years of measurements
Schulz, R.; Jehin, Emmanuel ULiege; Manfroid, Jean ULiege et al

in Planetary and Space Science (2008), 56

Over the past 10 years the isotopic ratios of carbon ([SUP]12[/SUP]C/[SUP]13[/SUP]C) and nitrogen ([SUP]14[/SUP]N/[SUP]15[/SUP]N) have been determined for a dozen comets, bright enough to allow obtaining ... [more ▼]

Over the past 10 years the isotopic ratios of carbon ([SUP]12[/SUP]C/[SUP]13[/SUP]C) and nitrogen ([SUP]14[/SUP]N/[SUP]15[/SUP]N) have been determined for a dozen comets, bright enough to allow obtaining the required measurements from the ground. The ratios were derived from high-resolution spectra of the CN coma measured in the B[SUP]2[/SUP]â [SUP]+[/SUP]â X[SUP]2[/SUP]â [SUP]+[/SUP] (0, 0) emission band around 387 nm. The observed comets belong to different dynamical classes, including dynamically new as well as long- and short-period comets from the Halley- and Jupiter-family. In some cases the comets could be observed at various heliocentric distances. All values determined for the carbon and nitrogen isotopic ratios were consistent within the error margin irrespective of the type of comet or the heliocentric distance at which it was observed. Our investigations resulted in average ratios of [SUP]12[/SUP]C/[SUP]13[/SUP]C=91±21 and nitrogen [SUP]14[/SUP]N/[SUP]15[/SUP]N=141±29. Whilst the value for the carbon isotopic ratio is in good agreement with the solar and terrestrial value of 89, the nitrogen isotopic ratio is very different from the telluric value of 272. [less ▲]

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See detailIsotopic abundance of nitrogen and carbon in distant comets
Manfroid, Jean ULiege; Jehin, Emmanuel ULiege; Hutsemekers, Damien ULiege et al

in Astronomy and Astrophysics (2005), 432(Letters), 5-8

The [SUP]12[/SUP]C[SUP]14[/SUP]N/[SUP]12[/SUP]C[SUP]15[/SUP]N and [SUP]12[/SUP]C[SUP]14[/SUP]N/[SUP]13[/SUP]C[SUP]14[/SUP]N isotopic ratios have been determined in comets C/1995 O1 (Hale-Bopp), C/2001 Q4 ... [more ▼]

The [SUP]12[/SUP]C[SUP]14[/SUP]N/[SUP]12[/SUP]C[SUP]15[/SUP]N and [SUP]12[/SUP]C[SUP]14[/SUP]N/[SUP]13[/SUP]C[SUP]14[/SUP]N isotopic ratios have been determined in comets C/1995 O1 (Hale-Bopp), C/2001 Q4 (NEAT) and C/2003 K4 (LINEAR) at heliocentric distances of, respectively, 2.7, 3.7 and 2.6 AU. These ratios have also been measured at rË 1 AU. No significant differences were found between all determinations, nor with the value obtained for other comets. If confirmed, the discrepancy between the nitrogen isotopic ratios from optical and millimeter measurements on CN and HCN would rule out HCN as a major parent of the cometary CN radicals. Based on observations collected at the European Southern Observatory, Paranal, Chile (ESO Programmes 270.C-5043, 073.C-0525 and 274.C-5015). [less ▲]

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See detailIsotopic abundances of carbon and nitrogen in Jupiter-family and Oort Cloud comets
Hutsemekers, Damien ULiege; Manfroid, Jean ULiege; Jehin, Emmanuel ULiege et al

in Astronomy and Astrophysics (2005), 440(Letters), 21-24

The [SUP]12[/SUP]C[SUP]14[/SUP]N/[SUP]12[/SUP]C[SUP]15[/SUP]N and [SUP]12[/SUP]C[SUP]14[/SUP]N/[SUP]13[/SUP]C[SUP]14[/SUP]N isotopic ratios are determined for the first time in a Jupiter-family comet, 88P ... [more ▼]

The [SUP]12[/SUP]C[SUP]14[/SUP]N/[SUP]12[/SUP]C[SUP]15[/SUP]N and [SUP]12[/SUP]C[SUP]14[/SUP]N/[SUP]13[/SUP]C[SUP]14[/SUP]N isotopic ratios are determined for the first time in a Jupiter-family comet, 88P/1981 Q1 Howell, and in the chemically peculiar Oort Cloud comet C/1999 S4 (LINEAR). By comparing these measurements to previous ones derived for six other Oort Cloud comets (including one of Halley-type), we find that both the carbon and nitrogen isotopic ratios are constant within the uncertainties. The mean values are [SUP]12[/SUP]C/[SUP]13[/SUP]C ~= 90 and [SUP]14[/SUP]N/[SUP]15[/SUP]N ~=145 for the eight comets. These results strengthen the view that CN radicals originate from refractory organics formed in the protosolar molecular cloud and subsequently incorporated in comets. [less ▲]

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See detailIsotopic and geochemical constraints on the evolution of the Mazury granitoids (NE Poland)
Baginski, Boguslaw; Duchesne, Jean-Clair ULiege; Martin, Hervé et al

in Koslowski, A.; Wiszniewska, Janina (Eds.) Granitoids in Poland (2007)

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See detailIsotopic Composition and sources of Organic Carbon Pools within the Tana River Basin, (Kenya)
Tamooh, F.; Van Den Meersche, K.; Borges, Alberto ULiege et al

Poster (2011)

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See detailIsotopic composition of nitrogen species in groundwater under agricultural areas: A review
Nikolenko, Olha ULiege; Jurado Elices, Anna ULiege; Borges, Alberto ULiege et al

in Science of the Total Environment (2017)

This work reviews applications of stable isotope analysis to the studies of transport and transformation of N species in groundwater under agricultural areas. It summarizes evidence regarding factors ... [more ▼]

This work reviews applications of stable isotope analysis to the studies of transport and transformation of N species in groundwater under agricultural areas. It summarizes evidence regarding factors affecting the isotopic composition of NO3−, NH4+ and N2O in subsurface, and discusses the use of 11B, 18O, 13C, 34S, 87Sr/86Sr isotopes to support the analysis of δ15N values. The isotopic composition of NO3−, NH4+ and N2O varies depending on their sources and dynamics of N cycle processes. The reported δ15N-NO3− values for sources of NO3− are: soil organic N – +3‰–+8‰, mineral fertilizers – −8‰–+7‰; manure/household waste – +5‰ to +35‰. For NH4+ sources, the isotopic signature ranges are: organic matter – +2.4–+4.1‰, rainwater – −13.4–+2.3‰, mineral fertilizers –−7.4–+5.1‰, householdwaste –+5–+9‰; animalmanure–+8–+11‰. ForN2O, isotopic composition depends on isotopic signatures of substrate pools and reaction rates. δ15Nvalues of NO3− are influenced by fractionation effects occurring during denitrification (ɛ=5–40‰), nitrification (ɛ=5–35‰) and DNRA (ɛ not reported). The isotopic signature of NH4+ is also affected by nitrification and DNRA as well as mineralization (ɛ=1‰), sorption (ɛ=1–8‰), anammox (ɛ=4.3–7.4‰) and volatilization (ɛ=25‰). As for theN2O, production of N2O leads to its depletion in 15N, whereas consumption – to enrichment in 15N. The magnitude of fractionation effects occurring during the considered processes depends on temperature, pH, DO, C/NO3− ratio, size of the substrate pool, availability of electron donors, water content in subsoil, residence time, land use, hydrogeology. While previous studies have accumulated rich data on isotopic composition of NO3− in groundwater, evidence remains scarce in the cases of NH4+ and N2O. Further research is required to consider variability of δ15N-NH4+ and δ15N-N2O in groundwater across agricultural ecosystems. [less ▲]

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See detailIsotopic compositions of North Sea marine mammals
Damseaux, France ULiege; Pomeroy, Paddy; Sierbert, Ursula et al

Poster (2017)

For over a decade, the North Sea has been undergoing significant changes due to global changes and overfishing. We conducted meta-analyses on marine mammals sampled in the North Sea to test the potential ... [more ▼]

For over a decade, the North Sea has been undergoing significant changes due to global changes and overfishing. We conducted meta-analyses on marine mammals sampled in the North Sea to test the potential impact of changes in fish stocks on feeding behaviour of grey seals, harbour seals and harbour porpoises. Data included δ13C and δ15N values measured in blood cells and muscles from the three species. SIBER, an isotopic niche quantification approach, is used to highlight potential dietary similarity and thus competition between marine mammal species. Harbour seals sampled in Germany showed the highest δ15N values, reflecting a trophic position at the top of the food web, alongside grey seals. In contrast, harbour porpoises sampled from Germany displayed the lowest trophic position. The ellipse overlapping between German harbour and grey seals was very important, showing similarity in, and therefore potential competition for, food sources. On the other hand, the harbour seal and the harbour porpoise of Germany displayed extended ellipse size compared to the grey seal. This may be due to a more diverse diet and, perhaps, a more opportunistic foraging behaviour than grey seals. Surprisingly, another group of grey seals sampled at Isle of May, Scotland displayed lower δ15N values and a very small ellipse size compared to grey seals from Germany, presumably being even more selective in their prey choice. Nevertheless, comparing the trophic position of the groups of grey seals requires caution as the isotopic baseline differed between the two sampling areas. This study allowed the determination of the competition, the spatial variations and the trophic niches of marine mammals in the North Sea and will, at the end, evaluate the effects of the changes in the North Sea on the ecology of marine mammals. [less ▲]

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See detailIsotopic constraints on the Cenozoic evolution of the carbon cycle
François, Louis ULiege; Godderis, Y.

in Chemical Geology (1998), 145(3-4), 177-212

In the last few years, several models have been built to explore the Cenozoic evolution of the carbon and strontium cycles. Of particular interest is the study of the impact on the carbon cycle of major ... [more ▼]

In the last few years, several models have been built to explore the Cenozoic evolution of the carbon and strontium cycles. Of particular interest is the study of the impact on the carbon cycle of major mountain uplifts such as the Himalayan orogeny. To explain the Cenozoic increase in the measured seawater strontium isotopic ratio, it was recently proposed that the Himalyan uplift could be responsible for an enhanced consumption of atmospheric CO2 by continental silicate weathering. Here, a new model of the carbon cycle evolution over Cenozoic times is presented. It calculates the various fluxes involved in the organic and inorganic components of the carbon cycle from the seawater delta C-13, the biological isotopic fractionation in the ocean and the seafloor spreading rate. The model equilibrates the budgets of the carbon and alkalinity cycles on the million year timescale, assuming as many previous investigators that the system remains close to equilibrium. The validity of this equilibrium approximation is examined critically. Various sensitivity experiments are performed in order to test the impact of the model parameters on the results. The calculated history of the carbonate deposition rate is consistent with the available reconstruction. The continental silicate weathering rate calculated by the model appears to be widely insensitive to the model parameters, showing three distinct evolutions over the Cenozoic. The model indeed suggests a time of relative constancy of the silicate weathering flux before 40 Ma, followed by a period of slow decrease until 15 Ma and finally a marked increase up to the present. In a progressively cooler world, this evolution may be interpreted as a change from a 'chemically' controlled to a 'physically' controlled weathering regime. The evolution of continental silicate weathering thus partly appears decoupled from the increase in the observed seawater strontium isotopic ratio. For this reason, the evolution of the calculated riverine Sr-87/ Sr-86 ratio shows a strong increase over the Cenozoic, from about 0.710 to 0.712. However, this increase may largely be reduced by considering the recycling of a pelagic carbonate reservoir increasing over the Cenozoic or by assuming that seafloor basalt weathering is a CO2- or climate-dependent process. (C) 1998 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailIsotopic constraints on the genesis of the anorthosite suite of rocks
Demaiffe, Daniel; Weis, Dominique; Michot, Jean et al

in Chemical Geology (1986), 57

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See detailIsotopic half-life and enrichment factor in two species of European freshwater fish larvae: an experimental approach
Latli, Adrien; Sturaro, Nicolas ULiege; Dujardin, Nelson et al

in Rapid Communications in Mass Spectrometry (2017), 31(8), 685-692

RATIONALE: Stable isotope ratios of carbon and nitrogen are valuable tools for field ecologists to use to analyse animal diets. However, the application of these tools requires knowledge of the tissue ... [more ▼]

RATIONALE: Stable isotope ratios of carbon and nitrogen are valuable tools for field ecologists to use to analyse animal diets. However, the application of these tools requires knowledge of the tissue enrichment factor (TEF) and half-life (HL). We experimentally compared TEF and HL in two freshwater fish larvae. We hypothesised that chub had a better growth/tissue replacement ratio than roach, due to the use of a food closer to their natural diet. METHODS: We determined the isotopic HL, the TEF and the contribution of growth or metabolic tissue replacement to dynamic isotopic incorporation. After yolk sac resorption, larvae were fed for 5 weeks with prey similar to their natural diet (Artemia nauplii) up to the isotopic equilibrium followed by Chironomid larvae. Stable isotope measurements were carried out using a continuous flow isotope ratio mass spectrometer coupled to an elemental analyser. RESULTS: Changes in isotopic composition strongly followed the predictions of exponential growth and time-dependent models. The isotopic HL varied between 8.2 and 12.6 days and the TEF of nitrogen and carbon ranged from 1.7 to 2.1‰ and from –0.9 to 1.2 ‰, respectively. The incorporation of dietary 13C was due more to the production of new tissue (between 56 and 79%) than to the metabolic process. Chub allocated more energy to growth than roach and the Chironomidae diet contributed more to the consumers’ growth than the Artemia diet. CONCLUSIONS: Metabolic rates seemed lower for chub than for roach, especially when they were fed with Chironomidae. A Chironomidae-based diet would be more profitable to chub, and the high associated growth rate could increase the development of the fish larvae. The HL and TEF were in the range of those reported in the literature. These results will be helpful for field-based studies, because they can help to increase the accuracy of models. [less ▲]

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See detailIsotopic niches of Fin Whales from the Mediterranean Sea and the Celtic sea (North Atlantic)
Das, Krishna ULiege; Holleville, Ophélie; Ryan, Conor et al

in Marine Environmental Research (2017), 127

The fin whale (Balaenoptera physalus) is the most abundant and widespread mysticete species in the Mediterranean Sea, found mostly over deep, offshore waters of the western and central portion of the ... [more ▼]

The fin whale (Balaenoptera physalus) is the most abundant and widespread mysticete species in the Mediterranean Sea, found mostly over deep, offshore waters of the western and central portion of the region. In the Mediterranean, this species is known to feed mainly on krill, in contrast to its Atlantic counterpart, which displays a more diversified diet. The International Whaling Commission recognizes several managements units in the Atlantic and the Mediterranean Sea and the connectivity between these populations is still being debated. Questions remain about inter-individual feeding strategies and trophic ecology. The goal of this study was to compare isotopic niches of fin whales from the Mediterranean Sea and the Celtic Sea (North Atlantic). δ13C and δ15N values were analysed in 136 skin biopsies from free-ranging Mediterranean fin whales sampled in 2010 and 2011 during campaigns at sea. δ13C and δ15N values ranged from -20.4 to -17.1 ‰ and from 5.9 to 8.9 ‰, respectively. These values are in good agreement with those estimated previously from baleen plates from Mediterranean and North Atlantic fin whales. The narrow isotopic niche width of the Mediterranean fin whale (Standard Ellipses area SEAc) compared to the North Atlantic fin whale raises many concerns in the context of global changes and long-term consequences. One could indeed expect that species displaying narrow niches would be more susceptible to ecosystem fragmentation and other anthropogenic impacts. [less ▲]

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See detailIsotopic ratios and elemental contents as indicators of seagrass C processing and sewage influence in a tropical macrotidal ecosystem (Madagascar, Mozambic channel)
Lepoint, Gilles ULiege; Frederich, Bruno ULiege; Gobert, Sylvie ULiege et al

in Scientia Marina (2008), 72(1), 109-117

Isotopic ratios and elemental concentrations of carbon and nitrogen were measured in seven seagrass species colonising different tidal flats near Toliara (SW Madagascar) in order to determine the ... [more ▼]

Isotopic ratios and elemental concentrations of carbon and nitrogen were measured in seven seagrass species colonising different tidal flats near Toliara (SW Madagascar) in order to determine the potential use of these parameters for assessing C processing and sewage use by tropical seagrasses. Nitrogen concentrations measured in upper intertidal seagrasses near Toliara were almost twice those measured on the tidal flat near a healthy mangrove situated 20 km away from Toliara town. At Toliara Beach, δ15N values were correlated with the N concentrations of Halodule sp., one of the dominant species on the tidal flat. This correlation did not exist for Halophila ovalis, the other dominant species. An increase in N concentrations and δ15N values demonstrates the influence of sewage coming directly onto Toliara Beach on the N cycles of intertidal seagrasses. Nevertheless, this influence seems restricted to the upper littoral zone and was not the main cause of seagrass die-off. On the other hand, at the mangrove site, δ15N values were not correlated with the N concentrations of Halodule sp. or Thalassia hemprichii, showing that natural δ15N variability is driven by other factors than the δ15N of N sources. Moreover, inter-individual variability of δ15N values was greater than inter-specific or inter-site variability, making the δ15N difficult to interpret in the context of human-disturbance influence on the N cycle of tropical seagrasses. δ13C values were close to -9‰, indicating the use of HCO 3– as an inorganic carbon source by the seven investigated species. Contrary to our hypothesis, variation between sites and location on the tidal flat was limited, suggesting limited impact on δ13C values of sewage, emersion duration and mechanisms for HCO 3– incorporation. [less ▲]

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See detailIsotopic Ratios in a Peculiar Outbursting Comet
Yang, Bin; Hutsemekers, Damien ULiege; Shinnaka, Yoshiharu et al

in Bulletin of the American Astronomical Society (2017, October 01), 49

Isotopic ratios in comets provide keys for the understanding of the origin of cometary material, and the physical and chemical conditions in the early Solar Nebula. A newly discovered peculiar comet, C ... [more ▼]

Isotopic ratios in comets provide keys for the understanding of the origin of cometary material, and the physical and chemical conditions in the early Solar Nebula. A newly discovered peculiar comet, C/2015 ER61, underwent an outburst with a total brightness increase of 2 magnitudes on the night of April 4th, 2017. The sharp increase in brightness offers a rare opportunity to measure the isotopic ratios of the light elements of this comet. We obtained two high-resolution spectra of C/2015 ER61 with UVES on Apr. 13 and Apr. 17 respectively. At the time of our observations, the comet was fading gradually since the outburst. We measured the 12C/13C and 14N/15N isotopic ratios from the CN Violet (0,0) band. In addition, we determined the 14N/15N ratio in NH2 for C/2015 ER61 from four pairs of NH2 isotopologue lines. Some 18OH lines were detected but the S/N of these lines is too low to derive a reliable 18O/16O estimate. We will present our UVES spectra of C/2015 ER61, obtained shortly after the outburst. We will also present the comparison of the Isotopic ratios of C/2015 ER61 with those of other comets. [less ▲]

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See detailIsotopic Ratios in Comets: Status and Perspectives
Jehin, Emmanuel ULiege; Manfroid, Jean ULiege; Hutsemekers, Damien ULiege et al

in Earth, Moon, and Planets (2009), 105

Isotopic abundance ratios are excellently suited to probe the origin of solar system matter. We review the recent measurements of the isotopic ratios of the light elements (D/H, [SUP]12[/SUP]C/[SUP]13 ... [more ▼]

Isotopic abundance ratios are excellently suited to probe the origin of solar system matter. We review the recent measurements of the isotopic ratios of the light elements (D/H, [SUP]12[/SUP]C/[SUP]13[/SUP]C, [SUP]16[/SUP]O/[SUP]18[/SUP]O, [SUP]14[/SUP]N/[SUP]15[/SUP]N, [SUP]32[/SUP]S/[SUP]34[/SUP]S) in cometary dust and gas and discuss briefly their implications. Special emphasis will be put on the determinations and progress performed in the field over the past years thanks to high resolution spectroscopy of cometary comae obtained with the ESO Very Large Telescope. Future perspectives from space missions and ground-based observations with new large and extremely large telescopes operating in the optical, infrared and submillimeter wavelengths will be presented. [less ▲]

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