References of "Zucconi, J*-M"
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See detailA Search for Water Vaporization on Ceres
Rousselot, P.; Jehin, Emmanuel ULg; Manfroid, Jean ULg et al

in Astronomical Journal (The) (2011), 142

There are hints that the dwarf planet (1) Ceres may contain a large amount of water ice. Some models and previous observations suggest that ice could be close enough to the surface to create a flux of ... [more ▼]

There are hints that the dwarf planet (1) Ceres may contain a large amount of water ice. Some models and previous observations suggest that ice could be close enough to the surface to create a flux of water outward through the regolith. This work aims to confirm a previous detection of OH emission off the northern limb of Ceres with the International Ultraviolet Explorer (IUE). Such emission would be evidence of water molecules escaping from the dwarf planet. We used the Ultraviolet and Visual Echelle Spectrograph of the Very Large Telescope to obtain spectra off the northern and southern limbs of Ceres at several epochs. These spectra cover the 307-312 nm wavelength range corresponding to the OH (0,0) emission band, which is the brightest band of this radical, well known in the cometary spectra. These new observations, five times more sensitive than those from IUE, did not permit detection of OH around Ceres. We derive an upper limit for the water production of about ~7 × 10[SUP]25[/SUP] molecules s[SUP]-1[/SUP] and estimate the minimum thickness of the dust surface layer above the water ice layer (if present) to be about 20 m. . [less ▲]

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See detailIsotopic Ratios in Comets: Status and Perspectives
Jehin, Emmanuel ULg; Manfroid, Jean ULg; Hutsemekers, Damien ULg 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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See detailThe CN isotopic ratios in comets
Manfroid, Jean ULg; Jehin, Emmanuel ULg; Hutsemekers, Damien ULg et al

in Astronomy and Astrophysics (2009), 503

Our aim is to determine the isotopic ratios [SUP]12[/SUP]C/[SUP]13[/SUP]C and [SUP]14[/SUP]N/[SUP]15[/SUP]N in a variety of comets and link these measurements to the formation and evolution of the solar ... [more ▼]

Our aim is to determine the isotopic ratios [SUP]12[/SUP]C/[SUP]13[/SUP]C and [SUP]14[/SUP]N/[SUP]15[/SUP]N in a variety of comets and link these measurements to the formation and evolution of the solar system. The [SUP]12[/SUP]C/[SUP]13[/SUP]C and [SUP]14[/SUP]N/[SUP]15[/SUP]N isotopic ratios are measured for the CN radical by means of high-resolution optical spectra of the R branch of the B-X (0, 0) violet band. 23 comets from different dynamical classes have been observed, sometimes at various heliocentric and nucleocentric distances, in order to estimate possible variations of the isotopic ratios in parent molecules. The [SUP]12[/SUP]C/[SUP]13[/SUP]C and [SUP]14[/SUP]N/[SUP]15[/SUP]N isotopic ratios in CN are remarkably constant (average values of, respectively, 91.0 ± 3.6 and 147.8 ± 5.7) within our measurement errors, for all comets whatever their origin or heliocentric distance. While the carbon isotopic ratio does agree with the terrestrial value (89), the nitrogen ratio is a factor of two lower than the terrestrial value (272), indicating a fractionation in the early solar system, or in the protosolar nebula, common to all the comets of our sample. This points towards a common origin of the comets independently of their birthplaces, and a relationship between HCN and CN. Appendices and Table [see full textsee full textsee full text] are only available in electronic form at http://www.aanda.org Based on observations made with ESO Telescopes at the La Silla Paranal Observatory under programmes ID 268.C-5570, 270.C-5043, 073.C-0525, 274.C-5015 and 075.C-0355(A). [less ▲]

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See detailA Multi-Wavelength Simultaneous Study of the Composition of the Halley Family Comet 8P/Tuttle
Jehin, Emmanuel ULg; Bockelée-Morvan, Dominique; Dello Russo, N. et al

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

We report on simultaneous optical and infrared observations of the Halley Family comet 8P/Tuttle performed with the ESO Very Large Telescope. Such multi-wavelength and coordinated observations are a good ... [more ▼]

We report on simultaneous optical and infrared observations of the Halley Family comet 8P/Tuttle performed with the ESO Very Large Telescope. Such multi-wavelength and coordinated observations are a good example of what can be done to support space missions. From high resolution optical spectroscopy of the CN (0,0) 388 nm and NH[SUB]2[/SUB] (0,9,0) 610 nm bands using UVES at UT2 we determined [SUP]12[/SUP]C/[SUP]13[/SUP]C = 90 ± 10 and [SUP]14[/SUP]N/[SUP]15[/SUP]N = 150 ± 20 in CN and we derived a nuclear spin temperature of NH[SUB]3[/SUB] of 29 ± 1 K. These values are similar to those found in Oort-Cloud and Jupiter Family comets. From low resolution long slit spectroscopy with FORS1 at UT2 we determined the CN, C[SUB]3[/SUB] and C[SUB]2[/SUB] production rates and the parent and daughter scale lengths up to 5.2 10[SUP]5[/SUP] km tailward. From high resolution IR spectroscopy with CRIRES at UT1 we measured simultaneously the production rates and mixing ratios of H[SUB]2[/SUB]O, HCN, C[SUB]2[/SUB]H[SUB]2[/SUB], CH[SUB]4[/SUB], C[SUB]2[/SUB]H[SUB]6[/SUB], and CH[SUB]3[/SUB]OH. [less ▲]

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See detailThe 16OH/18OH and OD/OH isotope ratios in comet C/2002 T7 (LINEAR)
Hutsemekers, Damien ULg; Manfroid, Jean ULg; Jehin, Emmanuel ULg et al

in Astronomy and Astrophysics (2008), 490(Letters), 31-34

The [SUP]16[/SUP]OH/[SUP]18[/SUP]OH and OD/OH isotope ratios are measured in the Oort-Cloud comet C/2002 T7 (LINEAR) through ground-based observations of the OH A [SUP]2[/SUP]Σ[SUP]+[/SUP] - X [SUP]2 ... [more ▼]

The [SUP]16[/SUP]OH/[SUP]18[/SUP]OH and OD/OH isotope ratios are measured in the Oort-Cloud comet C/2002 T7 (LINEAR) through ground-based observations of the OH A [SUP]2[/SUP]Σ[SUP]+[/SUP] - X [SUP]2[/SUP]Π[SUB]i[/SUB] ultraviolet bands at 3063 à (0, 0) and 3121 à (1, 1) obtained with the Very Large Telescope (VLT) feeding the Ultraviolet-Visual Echelle Spectrograph (UVES). From the [SUP]16[/SUP]OH/[SUP]18[/SUP]OH ratio, we find [SUP]16[/SUP]O/[SUP]18[/SUP]O = 425 ± 55, equal within the uncertainties to the terrestrial value and to the ratio measured in other comets, although marginally smaller. We also estimate OD/OH from which we derive D/H = 2.5 ± 0.7à 10[SUP]-4[/SUP] in water. This value is compatible with the water D/H ratios evaluated in other comets and is marginally higher than the terrestrial value. Based on observations collected at the European Southern Observatory, Paranal, Chile (ESO Programme 073.C-0525). [less ▲]

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See detailIsotopic abundance in the CN coma of comets: Ten years of measurements
Schulz, R.; Jehin, Emmanuel ULg; Manfroid, Jean ULg 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 detailLarge Excess of Heavy Nitrogen in Both Hydrogen Cyanide and Cyanogen from Comet 17P/Holmes
Bockelée-Morvan, D.; Biver, N.; Jehin, Emmanuel ULg et al

in Astrophysical Journal (2008), 679(Letters), 49-52

From millimeter and optical observations of the Jupiter-family comet 17P/Holmes performed soon after its huge outburst of 2007 October 24, we derive [SUP]14[/SUP]N/[SUP]15[/SUP]N = 139 +/- 26 in HCN and ... [more ▼]

From millimeter and optical observations of the Jupiter-family comet 17P/Holmes performed soon after its huge outburst of 2007 October 24, we derive [SUP]14[/SUP]N/[SUP]15[/SUP]N = 139 +/- 26 in HCN and [SUP]14[/SUP]N/[SUP]15[/SUP]N = 165 +/- 40 in CN, establishing that HCN has the same nonterrestrial isotopic composition as CN. The same conclusion is obtained for the long-period comet C/1995 O1 (Hale-Bopp) after a reanalysis of previously published measurements. These results are compatible with HCN being the prime parent of CN in cometary atmospheres. The [SUP]15[/SUP]N excess relative to the Earth's atmospheric value indicates that N-bearing volatiles in the solar nebula underwent important N isotopic fractionation at some stage of solar system formation. HCN molecules never isotopically equilibrated with the main nitrogen reservoir in the solar nebula before being incorporated in Oort Cloud and Kuiper Belt comets. The [SUP]12[/SUP]C/[SUP]13[/SUP]C ratios in HCN and CN are measured to be consistent with the terrestrial value. [less ▲]

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See detailA Search for Escaping Water from Ceres' Poles
Rousselot, P.; Mousis, O.; Dumas, C. et al

in Asteroids, Comets, Meteors 2008 (2008)

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See detailOptical Spectroscopy of the B and C Fragments of Comet 73P/Schwassmann-Wachmann 3 at the ESO VLT
Jehin, Emmanuel ULg; Manfroid, Jean ULg; Kawakita, H. et al

in LPI contribution 1405 (2008)

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See detailCarbon and Nitrogen Isotopic Ratios in Comets
Jehin, Emmanuel ULg; Manfroid, Jean ULg; Hutsemekers, Damien ULg et al

in LPI contribution 1405 (2008)

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See detailDeep Impact: High-Resolution Optical Spectroscopy with the ESO VLT and the Keck I Telescope
Jehin, Emmanuel ULg; Manfroid, Jean ULg; Hutsemekers, Damien ULg et al

in Astrophysical Journal (2006), 641(Letters), 145-148

We report on observations of comet 9P/Tempel 1 carried out before, during, and after the NASA Deep Impact event (UT July 4), with the optical spectrometers UVES and HIRES mounted on the telescopes Kueyen ... [more ▼]

We report on observations of comet 9P/Tempel 1 carried out before, during, and after the NASA Deep Impact event (UT July 4), with the optical spectrometers UVES and HIRES mounted on the telescopes Kueyen of the ESO VLT (Chile) and Keck I on Mauna Kea (Hawaii), respectively. A total observing time of about 60 hr, distributed over 15 nights around the impact date, allowed us (1) to find a periodic variation of 1.709 +/- 0.009 days in the CN and NH flux, explained by the presence of two major active regions; (2) to derive a lifetime >~5 × 10[SUP]4[/SUP] s (at 1.5 AU) for the parent of the CN radical from a simple modeling of the CN light curve after the impact; (3) to follow the gas and dust spatial profiles' evolution during the 4 hr following the impact and derive the projected velocities (400 and 150 m s[SUP]-1[/SUP], respectively); and (4) to show that the material released by the impact has the same carbon and nitrogen isotopic composition as the surface material ([SUP]12[/SUP]C/[SUP] 13[/SUP]C = 95 +/- 15 and [SUP]14[/SUP]N/[SUP]15[/SUP]N = 145 +/- 20). [less ▲]

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See detailDeep Impact: Observations from a Worldwide Earth-Based Campaign
Meech, K. J.; Ageorges, N.; A'Hearn, M. F. et al

in Science (2005), 310

On 4 July 2005, many observatories around the world and in space observed the collision of Deep Impact with comet 9P/Tempel 1 or its aftermath. This was an unprecedented coordinated observational campaign ... [more ▼]

On 4 July 2005, many observatories around the world and in space observed the collision of Deep Impact with comet 9P/Tempel 1 or its aftermath. This was an unprecedented coordinated observational campaign. These data show that (i) there was new material after impact that was compositionally different from that seen before impact; (ii) the ratio of dust mass to gas mass in the ejecta was much larger than before impact; (iii) the new activity did not last more than a few days, and by 9 July the comet's behavior was indistinguishable from its pre-impact behavior; and (iv) there were interesting transient phenomena that may be correlated with cratering physics. [less ▲]

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See detailIsotopic abundances of carbon and nitrogen in Jupiter-family and Oort Cloud comets
Hutsemekers, Damien ULg; Manfroid, Jean ULg; Jehin, Emmanuel ULg 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 abundance of nitrogen and carbon in distant comets
Manfroid, Jean ULg; Jehin, Emmanuel ULg; Hutsemekers, Damien ULg 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 detailThe deep impact campaign at ESO: the gas component
Rauer, H.; Jehin, Emmanuel ULg; Manfroid, Jean ULg et al

Poster (2005)

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See detailThe Anomalous 14N/15N Ratio in Comets 122P/1995 S1 (de Vico) and 153P/2002 C1 (Ikeya-Zhang)
Jehin, Emmanuel ULg; Manfroid, Jean ULg; Cochran, A. L. et al

in Astrophysical Journal (2004), 613(Letters), 161-164

High-resolution (R~60,000) spectra of the CN B[SUP]2[/SUP]Sigma[SUP]+[/SUP]-X[SUP]2[/SUP]Sigma[SUP]+[/SUP] (0, 0) band (near 3880 Å) in the Halley-type comet 122P/1995 S1 de Vico (with a period of 74 yr ... [more ▼]

High-resolution (R~60,000) spectra of the CN B[SUP]2[/SUP]Sigma[SUP]+[/SUP]-X[SUP]2[/SUP]Sigma[SUP]+[/SUP] (0, 0) band (near 3880 Å) in the Halley-type comet 122P/1995 S1 de Vico (with a period of 74 yr) and the ``intermediate-period'' comet 153P/2002 C1 Ikeya-Zhang (P~370 yr) were obtained with the 2dcoudé spectrograph at the 2.7 m Harlan J. Smith telescope of the McDonald Observatory. The comets were within 1 AU from the Sun (0.66 and 0.92 AU, respectively) at the time of the observations. While the measured [SUP]12[/SUP]C/[SUP]13[/SUP]C isotope ratios of both comets (90+/-10 and 90+/-25, respectively) are in very good agreement with the solar system value, the [SUP]14[/SUP]N/[SUP]15[/SUP]N ratios (140+/-20 and 170+/-50, respectively) are approximately half the value in Earth's atmosphere. The similarity is striking between these ratios and those obtained recently for two other long-period Oort Cloud comets, C/1995 O1 (Hale-Bopp) and C/2000 WM1 (LINEAR). While these optical determinations of [SUP]14[/SUP]N/[SUP]15[/SUP]N are consistent with each other, they disagree with those obtained in comet Hale-Bopp from submillimeter measurements of HCN, generally believed to be the main parent of CN. This puzzling difference points toward the existence of (an)other unknown parent(s) of CN, with an even higher [SUP]15[/SUP]N excess. Organic compounds like those found in interplanetary dust particles are good candidates. [less ▲]

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See detailThe nitrogen isotope ratio in a few Oort Cloud comets
Jehin, Emmanuel ULg; Arpigny, Claude ULg; Manfroid, Jean ULg et al

in 35th COSPAR Scientific Assembly (2004)

In the past few years, high-resolution (R ˜ 70,000) and high quality spectra of the CN B^2Sigma^+ - X^2Sigma^+ (0,0) band (at 388 nm) of several Oort Could comets have been collected by our team in ... [more ▼]

In the past few years, high-resolution (R ˜ 70,000) and high quality spectra of the CN B^2Sigma^+ - X^2Sigma^+ (0,0) band (at 388 nm) of several Oort Could comets have been collected by our team in different observatories and have allowed the first optical detections of [SUP]12[/SUP]C[SUP]15[/SUP]N. Observations with first class spectrographs on large 8m telescopes, such as UVES at the ESO VLT, have shown that such very efficient equipment are able to provide isotopic ratios for comets as faint as m_r ˜ 9 (heliocentric magnitude), opening up the possibility of carrying out a systematic analysis over a significant sample of comets. While the measured [SUP]12[/SUP]C/[SUP]13[/SUP]C isotope ratios in the different comets are in good agreement with the Solar system value (89), the derived [SUP]14[/SUP]N/[SUP]15[/SUP]N ratios are only about half the value in Earth's atmosphere (272), indicating an excess of [SUP]15[/SUP]N by a factor of about 2 with respect to the "cosmic" value. It is striking to note that the optical determinations of [SUP]14[/SUP]N/[SUP]15[/SUP]N in the different comets are consistent with each other (140 � 30), but not with the ratios derived for comet Hale-Bopp from sub-millimeter measurements on HCN, generally believed to be the main parent of CN. This discrepancy could indicate the existence of (an) other unknown parent(s) of CN, with an even higher [SUP]15[/SUP]N excess. Organic compounds like those found in interplanetary dust particles (IDPs) are good candidates. Further determinations from HCN are now badly needed in other comets. Obtaining the value of the N isotopic ratio in Jupiter-family short-period comets would be of great significance in view of their presumed different place of birth. Much is also expected in this respect, as in many others, from several space missions such as Deep Impact, Stardust, and Rosetta. [less ▲]

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See detailAnomalous 14N/15N ratio in comets 122P/1995 S1 (de Vico) and 153P/2002 C1 (Ikeya-Zhang)
Arpigny, Claude ULg; Cochran, A. L.; Jehin, Emmanuel ULg et al

in Bulletin of the American Astronomical Society (2003, May 01), 35

High-resolution (R 60,000) spectra of the Halley-type comet 122P/1995 S1 de Vico (Period 74 years) and the ``intermediate-period" comet 153P/2002 C1 Ikeya-Zhang (P 370 yr) were obtained with the 2DCoude ... [more ▼]

High-resolution (R 60,000) spectra of the Halley-type comet 122P/1995 S1 de Vico (Period 74 years) and the ``intermediate-period" comet 153P/2002 C1 Ikeya-Zhang (P 370 yr) were obtained with the 2DCoude spectrograph at the 2.7-m Harlan J. Smith telescope of the McDonald Observatory. These comets were within 1 AU from the Sun (0.66 and 0.92 AU, respectively). The spectra display CN (0,0) bands indicating an anomalous [SUP]14[/SUP]N/[SUP]15[/SUP]N isotope ratio, in the sense that it is close to half the value in Earth's atmosphere (the so-called ``Solar system value") and about half that obtained in comet Hale-Bopp from sub-millimeter measurements on HCN, generally believed to be the main parent of CN. Similar conclusions had been reached for C/1995 O1 (Hale-Bopp), an ``old long-period", and for C/2000 WM1 (LINEAR), a ``young long-period" comet. As suggested by Arpigny et al. (2003), this apparent abundance anomaly points towards the existence of other unknown parent(s) of CN, with an even higher [SUP]15[/SUP]N excess. Organic compounds like those found in interplanetary dust particles (IDPs) are good candidates. The similarity between comets of different dynamical ages is pointed out. 1 Research Director FNRS (Belgium) 2 Research Associate FNRS (Belgium) [less ▲]

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