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  1. Artikel: Abundances of sulphur molecules in the Horsehead nebula First NS

    Rivière-Marichalar, P / Fuente, A / Goicoechea, J R / Pety, J / Le Gal, R / Gratier, P / Guzmán, V / Roueff, E / Loison, J C / Wakelam, V / Gerin, M

    Astronomy and astrophysics

    2019  Band 628

    Abstract: Context: Sulphur is one of the most abundant elements in the Universe (S/H: Aims: Our goal is to complete the inventory of S-bearing molecules and their abundances in the prototypical photodissociation region (PDR) the Horsehead nebula to gain ... ...

    Abstract Context: Sulphur is one of the most abundant elements in the Universe (S/H
    Aims: Our goal is to complete the inventory of S-bearing molecules and their abundances in the prototypical photodissociation region (PDR) the Horsehead nebula to gain insight into sulphur chemistry in UV irradiated regions. Based on the WHISPER (Wide-band High-resolution Iram-30m Surveys at two positions with Emir Receivers) millimeter (mm) line survey, our goal is to provide an improved and more accurate description of sulphur species and their abundances towards the core and PDR positions in the Horsehead.
    Methods: The Monte Carlo Markov Chain (MCMC) methodology and the molecular excitation and radiative transfer code RADEX were used to explore the parameter space and determine physical conditions and beam-averaged molecular abundances.
    Results: A total of 13 S-bearing species (CS, SO, SO
    Conclusions: This is the first complete study of S-bearing species towards a PDR. Our study shows that CS, SO, and H
    Sprache Englisch
    Erscheinungsdatum 2019-07-29
    Erscheinungsland Germany
    Dokumenttyp Journal Article
    ZDB-ID 1458466-9
    ISSN 1432-0746 ; 0004-6361
    ISSN (online) 1432-0746
    ISSN 0004-6361
    DOI 10.1051/0004-6361/201935354
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  2. Artikel: The interstellar chemistry of C

    Loison, Jean-Christophe / Agúndez, Marcelino / Wakelam, Valentine / Roueff, Evelyne / Gratier, Pierre / Marcelino, Núria / Nuñez Reyes, Dianailys / Cernicharo, José / Gerin, Maryvonne

    Monthly notices of the Royal Astronomical Society

    2017  Band 470, Heft 4, Seite(n) 4075–4088

    Abstract: We report the detection of linear and cyclic isomers of ... ...

    Abstract We report the detection of linear and cyclic isomers of C
    Sprache Englisch
    Erscheinungsdatum 2017-10-09
    Erscheinungsland England
    Dokumenttyp Journal Article
    ZDB-ID 207232-4
    ISSN 0035-8711
    ISSN 0035-8711
    DOI 10.1093/mnras/stx1265
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  3. Artikel: Clustering the Orion B giant molecular cloud based on its molecular emission.

    Bron, Emeric / Daudon, Chloé / Pety, Jérôme / Levrier, François / Gerin, Maryvonne / Gratier, Pierre / Orkisz, Jan H / Guzman, Viviana / Bardeau, Sébastien / Goicoechea, Javier R / Liszt, Harvey / Öberg, Karin / Peretto, Nicolas / Sievers, Albrecht / Tremblin, Pascal

    Astronomy and astrophysics

    2018  Band 610

    Abstract: Context: Previous attempts at segmenting molecular line maps of molecular clouds have focused on using position-position-velocity data cubes of a single molecular line to separate the spatial components of the cloud. In contrast, wide field spectral ... ...

    Abstract Context: Previous attempts at segmenting molecular line maps of molecular clouds have focused on using position-position-velocity data cubes of a single molecular line to separate the spatial components of the cloud. In contrast, wide field spectral imaging over a large spectral bandwidth in the (sub)mm domain now allows one to combine multiple molecular tracers to understand the different physical and chemical phases that constitute giant molecular clouds (GMCs).
    Aims: We aim at using multiple tracers (sensitive to different physical processes and conditions) to segment a molecular cloud into physically/chemically similar regions (rather than spatially connected components), thus disentangling the different physical/chemical phases present in the cloud.
    Methods: We use a
    Results: A clustering analysis based only on the
    Conclusions: Molecules are versatile tracers of GMCs because their line intensities bear the signature of the physics and chemistry at play in the gas. The association of simultaneous multi-line, wide-field mapping and powerful machine learning methods such as the Meanshift clustering algorithm reveals how to decode the complex information available in these molecular tracers.
    Sprache Englisch
    Erscheinungsdatum 2018-02-12
    Erscheinungsland Germany
    Dokumenttyp Journal Article
    ZDB-ID 1458466-9
    ISSN 1432-0746 ; 0004-6361
    ISSN (online) 1432-0746
    ISSN 0004-6361
    DOI 10.1051/0004-6361/201731833
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  4. Artikel: Gas phase Elemental abundances in Molecular cloudS (GEMS): I. The prototypical dark cloud TMC 1.

    Fuente, A / Navarro, D G / Caselli, P / Gerin, M / Kramer, C / Roueff, E / Alonso-Albi, T / Bachiller, R / Cazaux, S / Commercon, B / Friesen, R / García-Burillo, S / Giuliano, B M / Goicoechea, J R / Gratier, P / Hacar, A / Jiménez-Serra, I / Kirk, J / Lattanzi, V /
    Loison, J C / Malinen, J / Marcelino, N / Martín-Doménech, R / Muñoz-Caro, G / Pineda, J / Tafalla, M / Tercero, B / Ward-Thompson, D / Treviño-Morales, S P / Riviére-Marichalar, P / Roncero, O / Vidal, T / Ballester, Maikel Y

    Astronomy and astrophysics

    2019  Band 624

    Abstract: GEMS is an IRAM 30m Large Program whose aim is determining the elemental depletions and the ionization fraction in a set of prototypical star-forming regions. This paper presents the first results from the prototypical dark cloud TMC 1. Extensive ... ...

    Abstract GEMS is an IRAM 30m Large Program whose aim is determining the elemental depletions and the ionization fraction in a set of prototypical star-forming regions. This paper presents the first results from the prototypical dark cloud TMC 1. Extensive millimeter observations have been carried out with the IRAM 30m telescope (3 mm and 2 mm) and the 40m Yebes telescope (1.3 cm and 7 mm) to determine the fractional abundances of CO, HCO
    Sprache Englisch
    Erscheinungsdatum 2019-04-19
    Erscheinungsland Germany
    Dokumenttyp Journal Article
    ZDB-ID 1458466-9
    ISSN 1432-0746 ; 0004-6361
    ISSN (online) 1432-0746
    ISSN 0004-6361
    DOI 10.1051/0004-6361/201834654
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  5. Artikel: Oxygen fractionation in dense molecular clouds.

    Loison, Jean-Christophe / Wakelam, Valentine / Gratier, Pierre / Hickson, Kevin M / Bacmann, Aurore / Agùndez, Marcelino / Marcelino, Nuria / Cernicharo, José / Guzman, Viviana / Gerin, Maryvonne / Goicoechea, Javier R / Roueff, Evelyne / Le Petit, Franck / Pety, Jérome / Fuente, Asunción / Riviere-Marichalar, Pablo

    Monthly notices of the Royal Astronomical Society

    2019  Band 485, Heft 4, Seite(n) 5777–5789

    Abstract: We have developed the first gas-grain chemical model for oxygen fractionation (also including sulphur fractionation) in dense molecular clouds, demonstrating that gas-phase chemistry generates variable oxygen fractionation levels, with a particularly ... ...

    Abstract We have developed the first gas-grain chemical model for oxygen fractionation (also including sulphur fractionation) in dense molecular clouds, demonstrating that gas-phase chemistry generates variable oxygen fractionation levels, with a particularly strong effect for NO, SO, O
    Sprache Englisch
    Erscheinungsdatum 2019-02-27
    Erscheinungsland England
    Dokumenttyp Journal Article
    ZDB-ID 207232-4
    ISSN 0035-8711
    ISSN 0035-8711
    DOI 10.1093/mnras/stz560
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  6. Artikel: Chemical complexity in the horsehead photodissociation region.

    Guzmán, Viviana V / Pety, Jérôme / Gratier, Pierre / Goicoechea, Javier R / Gerin, Maryvonne / Roueff, Evelyne / Le Petit, Franck / Le Bourlot, Jacques

    Faraday discussions

    2014  Band 168, Seite(n) 103–127

    Abstract: The interstellar medium is known to be chemically complex. Organic molecules with up to 11 atoms have been detected in the interstellar medium, and are believed to be formed on the ices around dust grains. The ices can be released into the gas-phase ... ...

    Abstract The interstellar medium is known to be chemically complex. Organic molecules with up to 11 atoms have been detected in the interstellar medium, and are believed to be formed on the ices around dust grains. The ices can be released into the gas-phase either through thermal desorption, when a newly formed star heats the medium around it and completely evaporates the ices; or through non-thermal desorption mechanisms, such as photodesorption, when a single far-UV photon releases only a few molecules from the ices. The first mechanism dominates in hot cores, hot corinos and strongly UV-illuminated PDRs, while the second dominates in colder regions, such as low UV-field PDRs. This is the case of the Horsehead were dust temperatures are approximately eual to 20-30 K, and therefore offers a clean environment to investigate the role of photodesorption. We have carried out an unbiased spectral line survey at 3, 2 and 1mm with the IRAM-30m telescope in the Horsehead nebula, with an unprecedented combination of bandwidth, high spectral resolution and sensitivity. Two positions were observed: the warm PDR and a cold condensation shielded from the UV field (dense core), located just behind the PDR edge. We summarize our recently published results from this survey and present the first detection of the complex organic molecules HCOOH, CH2CO, CH3CHO and CH3CCH in a PDR. These species together with CH3CN present enhanced abundances in the PDR compared to the dense core. This suggests that photodesorption is an efficient mechanism to release complex molecules into the gas-phase in far-UV illuminated regions.
    Sprache Englisch
    Erscheinungsdatum 2014-09-05
    Erscheinungsland England
    Dokumenttyp Journal Article
    ISSN 1359-6640
    ISSN 1359-6640
    DOI 10.1039/c3fd00114h
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  7. Artikel: First Detection of Interstellar S

    Fuente, Asunción / Goicoechea, Javier R / Pety, Jerome / Le Gal, Romane / Martín-Doménech, Rafael / Gratier, Pierre / Guzmán, Viviana / Roueff, Evelyne / Loison, Jean Christophe / Muñoz Caro, Guillermo M / Wakelam, Valentine / Gerin, Maryvonne / Riviere-Marichalar, Pablo / Vidal, Thomas

    The astrophysical journal. Letters

    2018  Band 851

    Abstract: We present the first detection of gas phase ... ...

    Abstract We present the first detection of gas phase S
    Sprache Englisch
    Erscheinungsdatum 2018-05-13
    Erscheinungsland England
    Dokumenttyp Journal Article
    ZDB-ID 2207648-7
    ISSN 2041-8205 ; 0004-637X
    ISSN 2041-8205 ; 0004-637X
    DOI 10.3847/2041-8213/aaa01b
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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