Author: "GOICOECHEA, J." / Topic: astrophysics - Searchworks@Jio Institute Digital Library Search Results

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34 results on '"GOICOECHEA, J."'

1. Using SPICA Space Telescope to characterize Exoplanets

Author: Goicoechea, J. R., Swinyard, B., Tinetti, G., Nakagawa, T., Enya, K., Tamura, M., Ferlet, M., Isaak, K. G., Wyatt, M., Aylward, A. D., Barlow, M., Beaulieu, J. P., Boccaletti, A., Cernicharo, J., Cho, J., Claudi, R., Jones, H., Lammer, H., Leger, A., Martín-Pintado, J., Miller, S., Najarro, F., Pinfield, D., Schneider, J., Selsis, F., Stam, D. M., Tennyson, J., Viti, S., and White, G.
Subjects: Astrophysics
Abstract: We present the 3.5m SPICA space telescope, a proposed Japanese-led JAXA-ESA mission scheduled for launch around 2017. The actively cooled (<5 K), single aperture telescope and monolithic mirror will operate from ~3.5 to ~210 um and will provide superb sensitivity in the mid- and far-IR spectral domain (better than JWST at lambda > 18 um). SPICA is one of the few space missions selected to go to the next stage of ESA's Cosmic Vision 2015-2025 selection process. In this White Paper we present the main specifications of the three instruments currently baselined for SPICA: a mid-infrared (MIR) coronagraph (~3.5 to ~27 um) with photometric and spectral capabilities (R~200), a MIR wide-field camera and high resolution spectrometer (R~30,000), and a far-infrared (FIR ~30 to ~210 um) imaging spectrometer - SAFARI - led by a European consortium. We discuss their capabilities in the context of MIR direct observations of exo-planets (EPs) and multiband photometry/high resolution spectroscopy observations of transiting exo-planets. We conclude that SPICA will be able to characterize the atmospheres of transiting exo-planets down to the super-Earth size previously detected by ground- or space-based observatories. It will also directly detect and characterize Jupiter/Neptune-size planets orbiting at larger separation from their parent star (>5-10 AU), by performing quantitative atmospheric spectroscopy and studying proto-planetary and debris disks. In addition, SPICA will be a scientific and technological precursor for future, more ambitious, IR space missions for exo-planet direct detection as it will, for example, quantify the prevalence exo-zodiacal clouds in planetary systems and test coronographic techniques, cryogenic systems and lightweight, high quality telescopes. (abridged), Comment: A White Paper for ESA's Exo-Planet Roadmap Advisory Team, submitted on 2008 July 29
Published: 2008

2. Physical parameters for Orion KL from modelling its ISO high resolution far-IR CO line spectrum

Author: Lerate, M. R., Yates, J., Viti, S., Barlow, M. J., Swinyard, B. M., White, G. J., Cernicharo, J., and Goicoechea, J. R.
Subjects: Astrophysics
Abstract: As part of the first high resolution far-IR spectral survey of the Orion KL region (Lerate et al. 2006), we observed 20 CO emission lines with Jup=16 to Jup=39 (upper levels from approx 752 K to 4294 K above the ground state). Observations were taken using the Long Wavelength Spectrometer (LWS) on board the Infrared Space Observatory (ISO), in its high resolution Fabry-Perot (FP) mode (approx 33 km s$^{-1}$). We present here an analysis of the final calibrated CO data, performed with a more sophisticated modelling technique than hitherto, including a detailed analysis of the chemistry, and discuss similarities and differences with previous results. The inclusion of chemical modelling implies that atomic and molecular abundances are time-predicted by the chemistry. This provides one of the main differences with previous studies in which chemical abundances needed to be assumed as initial condition. The chemistry of the region is studied by simulating the conditions of the different known components of the KL region: chemical models for a hot core, a plateau and a ridge are coupled with an accelerated Lambda-iteration (ALI)radiative transfer model to predict line fluxes and profiles. We conclude that the CO transitions with 18
Published: 2008
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3. Sulfur chemistry in the Horsehead. An interferometric view of the Horsehead PDR

Author: Goicoechea, J. R., Pety, J., Gerin, M., Teyssier, D., Roueff, E., and Hily-Blant, P.
Subjects: Astrophysics
Abstract: Sulfur is an abundant element which remains undepleted in diffuse interstellar gas (Av<1) but it is traditionally assumed to deplete on dust grains at higher densities and larger Av. Photodissociation regions (PDRs) are an interesting intermediate medium between translucent and dark clouds where the chemistry and energetics are dominated by the illuminating FUV radiation field. Thus they can provide new insights about the sulfur depletion problem. However, physical and chemical gradients in PDRs take place at small angular scales (~1 to 10''). Aperture synthesis observations are therefore required to resolve such gradients. Besides, a complete understanding of molecular excitation is needed to correctly determine molecular abundances but also the preavailing physical conditions. Hence, multi-J observations at increasing frequencies are also required. Such high angular resolution and broad frequency coverage observations will be provided by ALMA in the near future. In this work we present IRAM-PdBI observations of the CS J=2-1 line toward the Horsehead PDR complemented with IRAM-30m observations of several rotational lines of different sulfur bearing molecules (CS, HCS+, SO, H2S, etc.). Photochemical and nonlocal, non-LTE radiative transfer models adapted to the Horsehead geometry have been developed. The gas phase sulfur abundance has been inferred in the PDR., Comment: 4 pages, 3 figures; to appear in Astrophysics and Space Science, special issue of "Science with ALMA: a new era for Astrophysics" conference, November, 13-17 2006, ed. R. Bachiller
Published: 2007

4. Molecular survey of CRL618

Author: Pardo, J. R., Cernicharo, J., Goicoechea, J. R., Guelin, M., and Asensio, A.
Subjects: Astrophysics
Abstract: We present the complete data set, model and line identification of a survey of the emission from the C-rich protoplanetary nebula CRL 618 performed with the IRAM-30m telescope in the following frequency ranges: 80.25-115.75 GHz, 131.25-179.25 GHz, and 204.25-275.250 GHz. A selection of lines from different species has been used in previous works to derive the structure of the source, its physical conditions and the chemical abundances in the different gas regions. In this work, we have used this information to run a global simulation of the spectrum in order to check the consistency of the model and to ease the task of line identification. The total number of lines that have a correspondence in both data and model is ~3100, although quite often in this object many lines blend into complex features so that the model, that takes into account line blending, is a key tool at this stage of the analysis. Of all the lines that we have been able to label, ~55% of them belong to the different forms of HC3N, and ~18% to those of HC5N. The density of remaining unidentified features above the 3sigma limit is only one per ~2.1 GHz (74 features), which is unprecedented in the analysis of this type of large millimeter-wave line surveys., Comment: Accepted in ApJ (November 2006). Figures bitmapped to lower resolution. The complete set of tables and figures will be published only electronically (ApJ online)
Published: 2007
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5. The ISO LWS high resolution spectral survey towards Sagittarius B2

Author: Polehampton, E. T., Baluteau, J. -P., Swinyard, B. M., Goicoechea, J. R., Brown, J. M., White, G. J., Cernicharo, J., and Grundy, T. W.
Subjects: Astrophysics
Abstract: A full spectral survey was carried out towards the Giant Molecular Cloud complex, Sagittarius B2 (Sgr B2), using the ISO Long Wavelength Spectrometer Fabry-Perot mode. This provided complete wavelength coverage in the range 47-196 um (6.38-1.53 THz) with a spectral resolution of 30-40 km/s. This is an unique dataset covering wavelengths inaccessible from the ground. It is an extremely important region of the spectrum as it contains both the peak of the thermal emission from dust, and crucial spectral lines of key atomic (OI, CII, OIII, NII and NIII) and molecular species (NH3, NH2, NH, H2O, OH, H3O+, CH, CH2, C3, HF and H2D+). In total, 95 spectral lines have been identified and 11 features with absorption depth greater than 3 sigma remain unassigned. Most of the molecular lines are seen in absorption against the strong continuum, whereas the atomic and ionic lines appear in emission (except for absorption in the OI 63 um and CII 158 um lines). Sgr B2 is located close to the Galactic Centre and so many of the features also show a broad absorption profile due to material located along the line of sight. A full description of the survey dataset is given with an overview of each detected species and final line lists for both assigned and unassigned features., Comment: Accepted for publication in MNRAS
Published: 2007
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6. Far-Infrared detection of H2D+ toward Sgr B2

Author: Cernicharo, J., Polehampton, E., and Goicoechea, J. R.
Subjects: Astrophysics
Abstract: We report on the first far-IR detection of H2D+, using the Infrared Space Observatory, in the line of sight toward Sgr B2 in the galactic center. The transition at 126.853 um connecting the ground level of o-H2D+, 1_1,1 with the the 2_1,2 level at 113 K, is observed in absorption against the continuum emission of the cold dust of the source. The line is broad, with a total absorption covering 350 km s^-1, i.e., similar to that observed in the fundamental transitions of H2O, OH and CH at ~179, 119 and 149 um respectively. For the physical conditions of the different absorbing clouds the H2D+ column density ranges from 2 to 5x10^13 cm^-2, i.e., near an order of magnitude below the upper limits obtained from ground based submillimeter telescopes. The derived H2D+ abundance is of a few 10^-10, which agrees with chemical models predictions for a gas at a kinetic temperature of ~20K., Comment: Accepted in ApJ letters. Non edited
Published: 2007
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7. The Water Vapor Abundance in Orion KL Outflows

Author: Cernicharo, J., Goicoechea, J. R., Daniel, F., Lerate, M. R., Barlow, M. J., Swinyard, B. M., van Dishoeck, E., Lim, T. L., Viti, S., and Yates, J.
Subjects: Astrophysics
Abstract: We present the detection and modeling of more than 70 far-IR pure rotational lines of water vapor, including the 18O and 17O isotopologues, towards Orion KL. Observations were performed with the Long Wavelength Spectrometer Fabry-Perot (LWS/FP; R~6800-9700) on board the Infrared Space Observatory (ISO) between ~43 and ~197 um. The water line profiles evolve from P-Cygni type profiles (even for the H2O18 lines) to pure emission at wavelengths above ~100 um. We find that most of the water emission/absorption arises from an extended flow of gas expanding at 25+-5 kms^-1. Non-local radiative transfer models show that much of the water excitation and line profile formation is driven by the dust continuum emission. The derived beam averaged water abundance is 2-3x10^-5. The inferred gas temperature Tk=80-100 K suggests that: (i) water could have been formed in the "plateau" by gas phase neutral-neutral reactions with activation barriers if the gas was previously heated (e.g. by shocks) to >500 K and/or (ii) H2O formation in the outflow is dominated by in-situ evaporation of grain water-ice mantles and/or (iii) H2O was formed in the innermost and warmer regions (e.g. the hot core) and was swept up in ~1000 yr, the dynamical timescale of the outflow., Comment: Accepted for publication in ApJ letters [2006 August 7] (5 pages 2, figures, not edited)
Published: 2006
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8. Low sulfur depletion in the Horsehead PDR

Author: Goicoechea, J. R., Pety, J., Gerin, M., Teyssier, D., Roueff, E., Hily-Blant, P., and Baek, S.
Subjects: Astrophysics
Abstract: We present 3.65''x3.34'' angular-resolution IRAM PdBI observations of the CS J=2-1 line toward the Horsehead Photodissociation Region (PDR), complemented with IRAM-30m single-dish observations of several rotational lines of CS, C34S and HCS+. We analyse the CS and HCS+ photochemistry, excitation and radiative transfer to obtain their abundances and the physical conditions prevailing in the cloud edge. Since the CS abundance scales to that of sulfur, we determine the gas phase sulfur abundance in the PDR, an interesting intermediate medium between translucent clouds (where sulfur remains in the gas phase) and dark clouds (where large depletions have been invoked). A nonlocal non-LTE radiative transfer code including dust and cosmic background illumination adapted to the Horsehead geometry has been developed to carefuly analyse the CS, C34S, HCS+ and C18O rotational line emission. We use this model to consistently link the line observations with photochemical models to determine the CS/HCS+/S/S+ structure of the PDR. The combination of CS, C34S and HCS+ observations together with the inclusion of the most recent CS collisional and chemical rates in our models implies that sulfur depletion invoked to account for CS and HCS+ abundances is much smaller than in previous studies., Comment: 20 pages, 17 figures, accepted in A&A, 2006 June 9 (Figs 1 & 4 are bitmaped)
Published: 2006
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9. A far-infrared molecular and atomic line survey of the Orion KL region

Author: Lerate, M. R., Barlow, M. J., Swinyard, B. M., Goicoechea, J. R., Cernicharo, J., Grundy, T. W., Lim, T. L., Polehampton, E. T., Baluteau, J. P., Viti, S., and Yates, J.
Subjects: Astrophysics
Abstract: We have carried out a high spectral resolution line survey towards the Orion Kleinmann-Low (KL) cluster from 44-188 um. The observations were taken with the Long Wavelength Spectrometer (LWS) in Fabry-Perot mode, on board the Infrared Space Observatory (ISO). A total of 152 lines are clearly detected and a further 34 features are present as possible detections. The spectrum is dominated by the molecular species H2O, OH and CO, along with [OI] and [CII] lines from PDR or shocked gas and [OIII], [NIII] lines from the foreground M42 HII region. Several isotopic species, as well as NH3, are also detected. HDO and H3O+ are tentatively detected for the first time in the far-infrared range towards Orion-KL. A basic analysis of the line observations is carried out, by comparing with previous measurements and published models and deriving rotational temperatures and column densities in the case of the molecular species. The complexity of the region requires more sophisticated models for the interpretation of all the line observations., Comment: Accepted by MNRAS 2006 April 28
Published: 2006
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10. Water Vapor around Sgr B2

Author: Cernicharo, J., Goicoechea, J. R., Pardo, J. R., and Ramos, A. Asensio
Subjects: Astrophysics
Abstract: We have conducted a study combining H2O lines in two spectral regions. First, Infrared Space Observatory observations of several H2O thermal lines seen in absorption toward Sgr B2(M) at a spectral resolution of 35 kms^-1 have been analyzed. Second, an IRAM-30m telescope map of the para-H2O 3_13-2_20 line at 183.31 GHz, seen in emission, has also been obtained and analyzed. The H2O lines seen in absorption are optically thick and are formed in the outermost gas of the condensations in front of the far-IR continuum sources. They probe a maximum visual extinction of ~5 to 10 mag. Radiative transfer models indicate that these lines are quite insensitive to temperature and gas density, and that IR photons from the dust play a dominant role in the excitation of the involved H2O rotational levels. The water vapor abundance in the region is (1-2)x10^-5. The relatively low H2O/OH abundance ratio in the region, 2-4, is a signature of UV photon dominated surface layers traced by far-IR observations., Comment: 17 pages, 10 figures (2 of them bitmapped to low resolution), 2 tables, accepted in ApJ, 2006, January 12
Published: 2006
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11. Observational evidence of the formation of cyanopolyynes in CRL618 through the polimerization of HCN

Author: Pardo, J. R., Cernicharo, J., and Goicoechea, J. R.
Subjects: Astrophysics
Abstract: The abundance ratio of consecutive members of the cyanopolyynes family has been explored in CRL618 using data acquired in a complete line survey covering the frequency range 81-356 GHz. The Jup range explored for the different molecules is the following: 1 to 4 for HCN and HNC, 9 to 39 for HC3N, 31 to 133 for HC5N, and 72 to 85 for HC7N (not detected beyond Jup=85). The lowest vibrationally excited state of HC7N (nu_15 at 62 cm^-1) has been tentatively detected. Data analysis has been performed by extending our previous geometrical and radiative transfer model of the slowly expanding envelope (SEE) surrounding the compact central continuum source of CRL 618, that was established from the study of rotational lines in several vibrationally excited states of HC_3N. The new lines analyzed here require to model the high velocity wind (HVW) component and the colder circumstellar gas, remnant of the AGB phase of CRL618. The derived HC3N/HC5N and HC5N/HC7N abundance ratios from this set of uniformly calibrated lines are between 3 and 6 in the different regions, similar to standard values in the CSM and ISM, and consistent with previous estimates obtained from ISO observations and chemical models. However, the abundance ratios of HC3N, HC5N and HC7N with respect to HCN are at least two orders of magnitude larger than those typical for AGB C-rich stars, such as IRC+10216. This fact indicates that, in the short transition toward the Planetary Nebula phase, HCN is quickly reprocessed into longer cyanopolyyne chains. A similar behavior was previously found in this object for the polyacetylenic chains (C(2n)H2)., Comment: 8 figures, accepted in ApJ main journal
Published: 2005
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12. The slowly expanding envelope of CRL618 probed with HC3N rotational ladders

Author: Pardo, J. R., Cernicharo, J., Goicoechea, J. R., and Phillips, T. G.
Subjects: Astrophysics
Abstract: Lines from HC3N and isotopic substituted species in ground and vibrationally excited states produce crowded millimeter and submillimeter wave spectra in the C-rich protoplanetary nebula CRL618. The complete sequence of HC3N rotational lines from J=9-8 to J=30-29 has been observed with the IRAM 30m telescope toward this object. Lines from a total of 15 different vibrational states (including the fundamental), with energies up to 1100 cm^-1, have been detected for the main HC3N isotopomer. In addition, the CSO telescope has been used to complement this study in the range J=31-30 to J=39-38, with detections in five of these states, all of them below 700 cm^-1. Vibrationally excited HC3N rotational lines exhibit P-Cygni profiles at 3 mm, evolving to pure emission lineshapes at shorter wavelengths. This evolution of the line profile shows little dependence on the vibrational state from which they rotational lines arise. The absorption features are formed against the continuum emission, which has been successfully characterized in this work due to the large frequency coverage. The HC3N column density in front of the the continuum source has been determined by comparing the output of an array of models to the data. The best fits are obtained for column densities in the range 2.0-3.5 10$^17 cm^-2, consistent with previous estimates from ISO data, and TK in the range 250 to 275 K, in very good agreement with estimates made from the same ISO data., Comment: 24 pages, 7 figures, accepted in ApJ part I (Jul. 8, 2004)
Published: 2004
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13. The far-IR spectrum of Sagittarius B2 region: Extended molecular absorption, photodissociation and photoionization

Author: Goicoechea, J. R., Rodriguez-Fernandez, N. J., and Cernicharo, J.
Subjects: Astrophysics
Abstract: We present large scale 9'x 27'(25 pc x 70 pc) far-IR observations around Sgr B2 using the Long-wavelength spectrometer (LWS) on board the Infrared Space Observatory (ISO). The spectra are dominated by the strong continuum emission of dust, the widespread molecular absorption of light hydrides (OH, CH and H2O) and the fine structure lines of [NII], [NIII], [OIII], [CII] and [OI]. The molecular richness in the outer layers of Sgr B2 is probed by the ISO-LWS Fabry-Perot (35 km s^-1) detections towards Sgr B2(M), where more that 70 lines from 15 molecular and atomic species are observed at high signal to noise ratio., Comment: 46 pages, 10 figures, 5 tables, accepted in ApJ part I. (Figs. 1, 2, 3, 9 and 10 have been bitmapped to low resolution)
Published: 2003
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14. Extended photoionization and photodissociation in Sgr B2

Author: Goicoechea, J. R., Rodriguez-Fernandez, N. J., and Cernicharo, J.
Subjects: Astrophysics
Abstract: We present large scale 9' x 27' (25 pc x 70 pc) far-IR observations of the Sgr B2 complex using the spectrometers on board the Infrared Space Observatory (ISO). The far-IR spectra are dominated by the strong continuum emission of dust and by the fine structure lines of high excitation potential ions (NII, NIII and OIII) and those of neutral or weakly ionized atoms (OI and CII). The line emission has revealed a very extended component of ionized gas. The study of the NIII 57 microns/NII 122 microns and OIII 52/88 microns line intensity ratios show that the ionized gas has a density of n_e~10^{2-3} cm^-3 while the ionizing radiation can be characterized by a diluted but hard continuum, with effective temperatures of ~35000 K. Photoionization models show that the total number of Lyman photons needed to explain such an extended component is approximately equal to that of the HII regions in Sgr B2(N) and (M) condensations. We propose that the inhomogeneous and clumpy structure of the cloud allows the radiation to reach large distances through the envelope. Therefore, photodissociation regions (PDRs) can be numerous at the interface of the ionized and the neutral gas. The analysis of the OI (63 and 145 microns) and CII (158 microns) lines indicates an incident far-UV field (G_0, in units of the local interstellar radiation field) of 10^{3-4} and a H density of 10^{3-4} cm^{-3} in such PDRs. We conclude that extended photoionization and photodissociation are also taking place in Sgr B2 in addition to more established phenomena such as widespread low--velocity shocks., Comment: 5 pages, to be published in: Astron. Nachr., Vol. 324, No. S1 (2003), Special Supplement "The central 300 parsecs of the Milky Way", Eds. A. Cotera, H. Falcke, T. R. Geballe, S. Markoff
Published: 2003
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15. A new infrared band in the Interstellar and Circumstellar Clouds: C_4 or C_4H?

Author: Cernicharo, J., Goicoechea, J. R., and Benilan, Y.
Subjects: Astrophysics
Abstract: We report on the detection with the Infrared Space Observatory (ISO) of a molecular band at 57.5 microns (174 cm^{-1}) in carbon-rich evolved stars and in Sgr B2. Taking into account the chemistry of these objects the most likelihood carrier is a carbon chain. We tentatively assign the band to the nu_5 bending mode of C_4 for which a wavenumber of 170-172.4 cm^{-1} has been derived in matrix experiments (Withey et al. 1991). An alternate carrier might be C_4H, although the frequency of its lowest energy vibrational bending mode, nu_7, is poorly known (130-226 cm^{-1}). If the carrier is C_4, the derived maximum abundance is nearly similar to that found for C_3 in the interstellar and circumstellar media by Cernicharo, Goicoechea & Caux (2000). Hence, tetra-atomic carbon could be one of the most abundant carbon chain molecules in these media., Comment: 11 pages, 1 figure, accepted in ApJ Letters
Published: 2002
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16. Far-Infrared OH fluorescent emission in Sagittarius B2

Author: Goicoechea, J. R. and Cernicharo, J.
Subjects: Astrophysics
Abstract: We present Infrared Space Observatory (ISO) observations of 16OH and 18OH toward Sgr B2 with a spectral resolution of 35 km/s. The OH J=5/2-3/2 and J=3/2-1/2 rotational lines of the 2Pi1/2 ladder are seen in emission while the cross-ladder transitions (from the 2Pi3/2 J=3/2 to the J=1/2, 3/2 and 5/2 levels of the 2Pi1/2ladder), and the 2Pi3/2 J=5/2-3/2 and J=7/2-5/2 lines are detected in absorption. The 18OH 2Pi3/2 J=5/2-3/2 Lambda-doublet at 120 mu is also observed in absorption. All OH Lambda-doublets are resolved (except the 98 mu) and show, in addition to the strong absorption at the velocity of Sgr B2, several velocity components associated to the gas surrounding Sgr B2 and to the foreground clouds along the line of sight. No asymmetries in the line intensities of each doublet have been observed. We have modeled the observations using a non-local radiative transfer code and found that the OH absorption/emission must arise in a shell around Sgr B2 not resolved by the ISO/LWS beam. The gas density is moderate, with upper limits of 10^4 cm^{-3} and 300 K in temperature. The OH abundance is high,(2-5)10^{-6}. We argue that a widespread photon dominated region explains the enhancement of OH abundance., Comment: 13 pages, 2 figures, accepted in ApJ Letters
Published: 2002
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17. Chemical Evolution of the Circumstellar Envelopes of Carbon-rich Post-AGB objects

Author: Herpin, F., Goicoechea, J. R., Pardo, J. R., and Cernicharo, J.
Subjects: Astrophysics
Abstract: We have observed with the 30-m IRAM telescope, the CSO telescope and the ISOsatellite (Infrared Space Observatory) the rotational lines of CO at millimeter, submillimeter and far infrared wavelengths in the direction of C-rich stellar objects at different stages of evolution : CRL 2688 (a very young Proto-Planetary Nebula), CRL 618 (a Proto-Planetary Nebula), and NGC 7027 (a young Planetary Nebula). Several changes in the longwave emission of CO and other molecules are discussed here in relation with the degree of evolution of the objects. In the early stages, represented by CRL 2688, the longwave emission is dominated by CO lines. In the intermediate stage, CRL 618, very fast outflows are present which, together with the strong UV field from the central star, dissociate CO. The released atomic oxygen is seen via its atomic lines, and allows the formation of new O-bearing species, such as water and OH. The abundance of HNC is enhanced with respect to HCN as a result of the chemical processes occurring in the photo-dissociation region (PDR). At this stage, CO lines and [OI] lines are the dominant coolants, while the cooling effect of [CII] is rising. At the Planetary Nebula stage, NGC 7027, large parts of the old CO AGB material have been reprocessed. The spectrum is then dominated by atomic and ionic lines. New species such as CH+ appear. Water has probably been reprocessed in OH., Comment: 14 pages, 4 figures, accepted in ApJ
Published: 2002
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18. Water in star-forming regions: Physics and chemistry from clouds to disks as probed by Herschel spectroscopy

Author: van Dishoeck, E. F., Kristensen, L. E., Mottram, J. C., Benz, A. O., Bergin, E. A., Caselli, P., Herpin, F., Hogerheijde, M. R., Johnstone, D., Liseau, R., NISINI, Brunella, Tafalla, M., van der Tak, F. F. S., Wyrowski, F., Baudry, A., BENEDETTINI, Milena, Bjerkeli, P., Blake, G. A., Braine, J., Bruderer, S., Cabrit, S., Cernicharo, J., Choi, Y., Coutens, A., de Graauw, Th., Dominik, C., FEDELE , DAVIDE, Fich, M., Fuente, A., Furuya, K., Goicoechea, J. R., Harsono, D., Helmich, F. P., Herczeg, G. J., Jacq, T., Karska, A., Kaufman, M., Keto, E., Lamberts, T., Larsson, B., Leurini, Silvia, Lis, D. C., Melnick, G., Neufeld, D., Pagani, L., Persson, M., Shipman, R., TAQUET, VIANNEY DANIEL FRANCOIS, van Kempen, T. A., Walsh, C., Wampfler, S. F., Yıldız, U., WISH Team, Astronomy, Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA (UMR_8112)), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY), and Low Energy Astrophysics (API, FNWI)
Subjects: Protoplanetary disks, 010504 meteorology & atmospheric sciences, 530 Physics, Astrophysics - astrophysics of galaxies, Stars: formation, FOS: Physical sciences, Astrophysics, Astrophysics - Earth and planetary astrophysics, 01 natural sciences, Luminosity, 0103 physical sciences, Protostar, Astrophysics::Solar and Stellar Astrophysics, Spectroscopy, 010303 astronomy & astrophysics, molecules [ISM], Physics::Atmospheric and Oceanic Physics, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Line (formation), Astrochemistry, Earth and Planetary Astrophysics (astro-ph.EP), Physics, [PHYS]Physics [physics], Infrared: ISM, formation [stars], astrochemistry, jets and outflows [ISM], 520 Astronomy, protoplanetary disks, Water gas, ISM [infrared], Astronomy and Astrophysics, ISM: molecules, ISM: jets and outflows, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Excited state, Outflow, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Water vapor
Abstract: (abridged) Data and results from the WISH key program are summarized, designed to provide a legacy data set to address its physics and chemistry. WISH targeted ~80 sources along the two axes of luminosity and evolutionary stage: from low- to high-mass protostars and from pre-stellar cores to protoplanetary disks. Lines of H2O, HDO, OH, CO and [O I] were observed with the HIFI and PACS instruments, complemented by molecules that probe UV, X-ray or grain chemistry. Most of the far-infrared water emission from protostars is found to be compact, originating from warm outflowing and shocked gas at high density and temperature in at least two physical components. This gas is not probed by low-J CO lines, only by J>14. Water is a significant, but not dominant, coolant. Its abundance is universally low, of order H2O/H2=2E-6, pointing to shock and outflow cavity models that include UV radiation at 100-1000 times the ISRF. In cold quiescent pre-stellar cores and envelopes, the water abundance structure is accurately probed through velocity-resolved line profiles, confirming basic chemistry networks. The gaseous HDO/H2O ratio of 0.025, much higher than that of bulk ice, is representative of the outer photodesorbed ice layers and cold chemistry. Water abundances in the inner hot cores are high, but with variations from 5E-6 to 2E-4. Combined analyses of water gas and ice show that up to 50% of the oxygen budget may be missing, with possible explanations discussed. Water vapor emission from disks is weak, indicating that water ice is locked up in larger pebbles early on and that these pebbles have settled and drifted inward by the Class II stage. Quantitatively, many oceans of water ice are available. Extragalactic low-J H2O emission is mostly compact and collisionally excited. Prospects for future mid- to far-infrared missions are given., 58 pages, 39 figures, accepted for publication in A&A
Published: 2021

19. Origins space telescope: from first light to life.

Author: Wiedner, M. C., Aalto, S., Armus, L., Bergin, E., Birkby, J., Bradford, C. M., Burgarella, D., Caselli, P., Charmandaris, V., Cooray, A., De Beck, E., Desert, J. M., Gerin, M., Goicoechea, J., Griffin, M., Hartogh, P., Helmich, F., Hogerheijde, M., Hunt, L., and Karska, A.
Subjects: SPACE telescopes, ASTROPHYSICS, ORIGIN of planets, ASTRONOMY, HEAVY elements, DWARF stars
Abstract: The Origins Space Telescope (Origins) is one of four science and technology definition studies selected by the National Aeronautics and Space Administration (NASA) in preparation of the 2020 Astronomy and Astrophysics Decadal survey in the US. Origins will trace the history of our origins from the time dust and heavy elements permanently altered the cosmic landscape to present-day life. It is designed to answer three major science questions: How do galaxies form stars, make metals, and grow their central supermassive black holes from reionization? How do the conditions for habitability develop during the process of planet formation? Do planets orbiting M-dwarf stars support life? Origins operates at mid- to far-infrared wavelengths from ~ 2.8 μm to 588 μm, and is more than 1000 times more sensitive than prior far-IR missions due to its cold (~ 4.5 K) aperture and state-of-the-art instruments. [ABSTRACT FROM AUTHOR]
Published: 2021
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20. HERSCHEL SURVEY OF GALACTIC OH + , H 2 O + , AND H 3 O + : PROBING THE MOLECULAR HYDROGEN FRACTION AND COSMIC-RAY IONIZATION RATE

Author: Iffrig, Olivier, Hennebelle, Patrick, Indriolo, Nick, Neufeld, D., Gerin, M., Schilke, P., Benz, A., Winkel, B., Menten, K., Chambers, E., Black, John, Bruderer, S., Falgarone, E., Godard, B., Goicoechea, J., Gupta, H., Lis, D., Ossenkopf, V., Persson, C., Sonnentrucker, P., Van Der Tak, F., Van Dishoeck, E., Wolfire, Mark, Wyrowski, F., Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS Paris)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Radioastronomie (MPIFR), Onsala space observatory (oso), Chalmers University of Technology [Göteborg], Max-Planck-Institut für Extraterrestrische Physik (MPE), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA (UMR_8112)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris-Seine-Université Paris-Seine-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Consejo Superior de Investigaciones Científicas [Spain] (CSIC), Laboratoire Univers et Théories (LUTH (UMR_8102)), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Department of Materials Science and Engineering, KTH (KTH), Department of Materials Science and Engineering, KTH, Leiden Observatory [Leiden], Universiteit Leiden [Leiden], École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Onsala Space Observatory (OSO), Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), National Aeronautics and Space Administration (US), Ministerio de Ciencia e Innovación (España), Ministerio de Economía y Competitividad (España), and Kapteyn Astronomical Institute
Subjects: Hydrogen, Astrophysics::High Energy Astrophysical Phenomena, Interstellar cloud, Continuum (design consultancy), chemistry.chemical_element, FOS: Physical sciences, Cosmic ray, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Ion, cosmic rays, Ionization, Disc, Astrophysics::Galaxy Astrophysics, ComputingMilieux_MISCELLANEOUS, Physics, [PHYS]Physics [physics], astrochemistry, Galactic Center, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, chemistry, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Astrochemistry - cosmic rays, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: In diffuse interstellar clouds the chemistry that leads to the formation of the oxygen-bearing ions OH+, H2O+, and H3O+ begins with the ionization of atomic hydrogen by cosmic rays, and continues through subsequent hydrogen abstraction reactions involving H2. Given these reaction pathways, the observed abundances of these molecules are useful in constraining both the total cosmic-ray ionization rate of atomic hydrogen (ζH) and molecular hydrogen fraction ($f_{\rm H_2}$). We present observations targeting transitions of OH+, H2O+, and H3O+ made with the Herschel Space Observatory along 20 Galactic sight lines toward bright submillimeter continuum sources. Both OH+ and H2O+ are detected in absorption in multiple velocity components along every sight line, but H3O+ is only detected along 7 sight lines. From the molecular abundances we compute $f_{\rm H_2}$ in multiple distinct components along each line of sight, and find a Gaussian distribution with mean and standard deviation 0.042 ± 0.018. This confirms previous findings that OH+ and H2O+ primarily reside in gas with low H2 fractions. We also infer ζH throughout our sample, and find a lognormal distribution with mean log (ζH) = –15.75 (ζH = 1.78 × 10–16 s–1) and standard deviation 0.29 for gas within the Galactic disk, but outside of the Galactic center. This is in good agreement with the mean and distribution of cosmic-ray ionization rates previously inferred from H$_3^+$ observations. Ionization rates in the Galactic center tend to be 10-100 times larger than found in the Galactic disk, also in accord with prior studies., Support for this work was provided by NASA through an award issued by JPL/Caltech. N.I. and D.A.N. are funded by NASA Research Support Agreement No. 1393741 provided through JPL. J.R.G. thanks the Spanish MINECO for funding support under grants CSD2009-00038 and AYA2012- 32032.
Published: 2015

21. Herschel spectral-mapping of the Helix Nebula (NGC 7293): Extended CO photodissociation and OH+ emission

Author: Etxaluze, M., Cernicharo, J., Goicoechea, J. R., van, Hoof P. A. M., Swinyard, B. M., Barlow, M. J., van, de Steene G. C., Groenewegen, M. A. T., Kerschbaum, F., Lim, T. L., Lique, F., Matsuura, M., Pearson, C., Polehampton, E. T., Royer, P., and Ueta, Toshiya
Subjects: Helix Nebula, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Context (language use), Astrophysics, Photodissociation region, 01 natural sciences, Spectral line, Atmospheric radiative transfer codes, photon-dominated region (PDR), 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Line (formation), infrared: ISM, Physics, 010308 nuclear & particles physics, Photodissociation, Astronomy and Astrophysics, Planetary nebula, Astrophysics - Astrophysics of Galaxies, ISM: molecules, ISM: lines and bands, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), planetary nebulae: individual: NGC7293
Abstract: 著者人数: 16名, Accepted: 2014-03-28, 資料番号: SA1140078000
Published: 2014
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22. The WADI key project: New insights to photon-dominated regions from Herschel observations

Author: Ossenkopf, V., Röllig, M., Kramer, C., Okada, Y., Fuente, A., Akyilmaz Yabaci, M., Benz, A. O., Berné, O., Boulanger, F., Bruderer, S., Dedes, C., France, K., Gerin, M., Goicoechea, J. R., Gusdorf, A., Güsten, R., Harris, A., Joblin, C., Klein, T., Latter, W., Le Petit, F., Lord, S., Martin, P. G., Pilleri, P., Martin-Pintado, J., Mookerjea, B., Neufeld, D. A., Phillips, T., Rizzo, R., Simon, R., Stutzki, J., van der Tak, F. F. S., Teyssier, D., Yorke, H., Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Physikalisches Institut [Köln], Universität zu Köln, Instituto de RadioAstronomía Milimétrica (IRAM), Centre National de la Recherche Scientifique (CNRS), foreign laboratories (FL), CERN [Genève], Observatorio Astronómico Nacional (OAN), oan, Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Extraterrestrische Physik (MPE), Institute of Astronomy [ETH Zürich], Department of Physics [ETH Zürich] (D-PHYS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Center for Astrophysics and Space Astronomy [Boulder] (CASA), University of Colorado [Boulder], Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA (UMR_8112)), Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Division for Submm Technologies, Max-Planck-Institut für Radioastronomie (MPIFR), CRUK Medical Oncology Unit, The Churchill Hospital, Univ Toulouse UPS, Ctr Etud Spatiale Rayonnements, F-31062 Toulouse 9, France, Centre Etud Spatiale Rayonnements Toulouse, Los Alamos National Laboratory (LANL), KOSMA, I. Physikalisches Institut, Department of Child and Adolescent Neurology and Psychiatry, Catania University, Helmholtz zentrum für Schwerionenforschung GmbH (GSI), European Space Astronomy Centre (ESAC), European Space Agency (ESA), Röllig, M. and Simon, R. and Ossenkopf, V. and Stutzki, J., Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Universität zu Köln = University of Cologne, Observatorio Astronomico Nacional, Madrid, Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS-PSL), Università degli studi di Catania = University of Catania (Unict), Agence Spatiale Européenne = European Space Agency (ESA), Astronomy, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich)-Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), PSL Research University (PSL)-PSL Research University (PSL)-Université de Cergy Pontoise (UCP), École normale supérieure - Paris (ENS Paris)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, and PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)
Subjects: Physics, geography, geography.geographical_feature_category, Photon, Molecular cloud, General Engineering, Energy balance, Measure (physics), Astronomy, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, 01 natural sciences, 13. Climate action, Space and Planetary Science, 0103 physical sciences, Key (cryptography), 010306 general physics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Wadi, ComputingMilieux_MISCELLANEOUS
Abstract: Within the Herschel key project "The Warm And Dense ISM" (WADI) we systematically observe a number of prominent photon-dominated regions (PDRs) to measure the impact of varying UV fields on the energy balance, the chemical and dynamical structure of heated molecular clouds.
Published: 2011

23. A high-resolution line survey of IRC+10216 with Herschel/HIFI. First results: Detection of warm silicon dicarbide (SiC2)

Author: Cernicharo, J., Waters, L.B.F.M., Decin, L., Encrenaz, P., Tielens, A. G. G. M., Agúndez, M., De Beck, E., Müller, H. S. P., Goicoechea, J. R., Barlow, M.J., Benz, A., Crimier, N., Daniel, F., Di Giorgio, A. M., Fich, M., Gaier, T., García-Lario, P., de Koter, A., Khouri, T., Liseau, R., Lombaert, R., Erickson, N., Pardo, J. R., Pearson, J. C., Shipman, R., Sánchez Contreras, C., Teyssier, D., Astrophysics, Afd Astrophysics begr 1/1/17, Centro de Astrobiología, Consejo Superior de Investigaciones Científicas (CSIC)/Instituto Nacional de Técnica Aeroespacial (INTA) (CAB), Astronomical Institute Anton Pannekoek, University of Amsterdam, Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Instrumentation et télédétection, Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique et Atmosphères = Laboratory for Studies of Radiation and Matter in Astrophysics and Atmospheres (LERMA), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY), Leiden Observatory, Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Instituut voor Sterrenkunde, Katholieke Universiteit Leuven, Physikalisches Institut, Universität zu Köln, University College of London [London] (UCL), Institute for Astronomy, Department of Physics, ETH Zürich, Istituto di Fisica dello Spazio Interplanetario (IFSI), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Department of Physics and Astronomy, University of Waterloo, Jet Propulsion Laboratory, California Institute of Technology (JPL), European Space Astronomy Centre (ESAC), Agence Spatiale Européenne = European Space Agency (ESA), Department of Radio and Space Science, Chalmers University of Technology, Department of Astronomy, University of Massachusetts, SRON Netherlands Institute for Space Research, Low Energy Astrophysics (API, FNWI), Astrophysics, and Afd Astrophysics begr 1/1/17
Subjects: Silicon, chemistry.chemical_element, FOS: Physical sciences, Astrophysics, stars: AGB and post-AGB, SUBMILLIMETER HCN LASER, COLOGNE DATABASE, Quality (physics), CHEMISTRY, LABORATORY MEASUREMENT, Line (formation), stars: individual: IRC+10216, Physics, ENVELOPE, Range (particle radiation), Spectrometer, astrochemistry, Hydrogen molecule, Resolution (electron density), Astronomy and Astrophysics, Rotational temperature, Astrophysics - Astrophysics of Galaxies, BURE OBSERVATIONS, CO, stars: carbon, chemistry, Space and Planetary Science, MOLECULAR-SPECTROSCOPY, Astrophysics of Galaxies (astro-ph.GA), stellar evolaution [astronomy and astrophysics], DUST FORMATION ZONE, EMISSION, AGB stars, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], line: identification
Abstract: We present the first results of a high-spectral-resolution survey of the carbon-rich evolved star IRC+10216 that was carried out with the HIFI spectrometer onboard Herschel. This survey covers all HIFI bands, with a spectral range from 488 to 1901GHz. In this letter we focus on the band-1b spectrum, in a spectral range 554.5-636.5GHz, where we identified 130 spectral features with intensities above 0.03 K and a signal-to-noise ratio >5. Detected lines arise from HCN, SiO, SiS, CS, CO, metal-bearing species and, surprisingly, silicon dicarbide (SiC2). We identified 55 SiC2 transitions involving energy levels between 300 and 900 K. By analysing these rotational lines, we conclude that SiC2 is produced in the inner dust formation zone, with an abundance of ~2x10^-7 relative to molecular hydrogen. These SiC2 lines have been observed for the first time in space and have been used to derive an SiC2 rotational temperature of ~204 K and a source-averaged column density of ~6.4x10^15 cm^-2. Furthermore, the high quality of the HIFI data set was used to improve the spectroscopic rotational constants of SiC2., A&A HIFI Special Issue, 2010
Published: 2010

24. Hydrides in Young Stellar Objects: Radiation tracers in a protostar-disk-outflow system

Author: Benz, A. O., Bruderer, S., van Dishoeck, E. F., Staeuber, P., Wampfler, S. F., Melchior, M., Dedes, C., Wyrowski, F., Doty, S. D., van der Tak, F., Baechtold, W., Csillaghy, A., Megej, A., Monstein, C., Soldati, M., Bachiller, R., Baudry, A., Benedettini, M., Bergin, E., Bjerkeli, P., Blake, G.A., Bontemps, S., Braine, J., Caselli, P., Cernicharo, J., Codella, C., Daniel, F., di Giorgio, A. M., Dieleman, P., Dominik, C., Encrenaz, P., Fich, M., Fuente, A., Giannini, T., Goicoechea, J. R., de Graauw, Th., Helmich, F., Herczeg, G. J., Herpin, F., Hogerheijde, M. R., Jacq, T., Jellema, W., Johnstone, D., Jorgensen, J. K., Kristensen, L. E., Larsson, B., Lis, D., Liseau, R., Marseille, M., McCoey, C., Melnick, G., Neufeld, D., Nisini, B., Olberg, M., Ossenkopf, V., Parise, B., Pearson, J. C., Plume, R., Risacher, C., Santiago-Garcia, J., Saraceno, P., Schieder, R., Shipman, R., Stutzki, J., Tafalla, M., Tielens, A. G. G. M., van Kempen, T. A., Visser, R., Yildiz, U. A., Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1, Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Civilisations atlantiques & Archéosciences (C2A), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ministère de la Culture et de la Communication (MCC)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Université de Nantes - UFR Histoire, Histoire de l'Art et Archéologie (UFR HHAA), Université de Nantes (UN)-Université de Nantes (UN), SRON Netherlands Institute for Space Research (SRON), Université de Nantes - UFR Histoire, Histoire de l'Art et Archéologie (UFR HHAA), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Ministère de la Culture et de la Communication (MCC), Low Energy Astrophysics (API, FNWI), and Astronomy
Subjects: H3O+, Astronomy, Young stellar object, FOS: Physical sciences, Context (language use), Astrophysics, Radiation, 01 natural sciences, 7. Clean energy, W3IRS5, photon-dominated region, CHEMISTRY, 0103 physical sciences, Protostar, H2O+, 010306 general physics, 010303 astronomy & astrophysics, QB, Line (formation), Physics, stars: formation, SPECTROSCOPY, astrochemistry, DR21, Star formation, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Astronomy and Astrophysics, REGIONS, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Astrophysics - Astrophysics of Galaxies, stars: massive, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), ComputingMethodologies_DOCUMENTANDTEXTPROCESSING, submillimeter: ISM, Outflow, Absorption (chemistry), line: identification
Abstract: Context: Hydrides of the most abundant heavier elements are fundamental molecules in cosmic chemistry. Some of them trace gas irradiated by UV or X-rays. Aims: We explore the abundances of major hydrides in W3 IRS5, a prototypical region of high-mass star formation. Methods: W3 IRS5 was observed by HIFI on the Herschel Space Observatory with deep integration (about 2500 s) in 8 spectral regions. Results: The target lines including CH, NH, H3O+, and the new molecules SH+, H2O+, and OH+ are detected. The H2O+ and OH+ J=1-0 lines are found mostly in absorption, but also appear to exhibit weak emission (P-Cyg-like). Emission requires high density, thus originates most likely near the protostar. This is corroborated by the absence of line shifts relative to the young stellar object (YSO). In addition, H2O+ and OH+ also contain strong absorption components at a velocity shifted relative to W3 IRS5, which are attributed to foreground clouds. Conclusions: The molecular column densities derived from observations correlate well with the predictions of a model that assumes the main emission region is in outflow walls, heated and irradiated by protostellar UV radiation., Comment: Astronomy and Astrophysics Letters, in press
Published: 2010

25. The space infrared telescope for cosmology and astrophysics: SPICA A joint mission between JAXA and ESA

Author: SWINYARD, Bruce, NAKAGAWA, Takao, MERKEN, Patrick, ROYER, Pierre, SOUVERIJNS, Tim, VANDENBUSSCHE, Bart, WAELKENS, Christoffel, DAVIS, Peter, DI FRANCESCO, James, HALPERN, Mark, HOUDE, Martin, JOHNSTONE, Doug, JONCAS, Gilles, NAYLOR, David, PLUME, Rene, SCOTT, Douglas, ABERGEL, A., BENSAMMAR, S., BRAINE, J., BUAT, V., BURGARELLA, D., CAIS, Ph., DOLE, H., DUBAND, L., ELBAZ, D., GERIN, M., GIARD, M., GOICOECHEA, J., JOBLIN, C., JONES, A., KNEIB, J. P., LAGACHE, Guilaine, MADDEN, S., PONS, R., PAJOT, F., RAMBAUD, D., RAVERA, L., RISTORCELLI, I., RODRIGUEZ, L., VIVES, S., ZAVAGNO, Annie, GEIS, Norbert, KRAUSE, Oliver, LUTZ, Dieter, POGLITSCH, Albrecht, RAAB, Walfried, STEGMAIER, Jutta, STURM, Eckhard, TUFFS, Richard, LEE, Hyung Mok, KOO, Bon-Chul, IM, Myungshin, PAK, Soojong, HAN, Wonyong, PARK, Jang-Hyun, NAM, Uk-Won, JIN, Ho, LEE, Dae-Hee, YUK, In-Soo, LEE, Sungho, AIKAWA, Yuri, ARIMOTO, Nobuo, DOI, Yasuo, ENYA, Keigo, FUKAGAWA, Misato, FURUSHO, Reiko, HASEGAWA, Sunao, HAYASHI, Masahiko, HONDA KANAGAWA, Mitsuhiko, IDA, Shigeru, IMANISHI, MASATOSHI, INUTSUKA, Shu-Ichiro, IZUMIURA, Hideyuki, KAMAYA, Hideyuki, KANEDA, Hidehiro, KASUGA, Toshihiro, KATAZA, Hirokazu, KAWABATA, Koji, KAWADA, Mitsunobu, KAWAKITA, Hideyo, KII, Tsuneo, KODA, Jin, KODAMA, Tadayuki, KOKUBO, Eiichiro, KOMATSU, Keiji, MATSUHARA, Hideo, MATSUMOTO, Toshio, MATSUURA, Shuji, MIYATA, Takashi, MIYATA, Murakam, NAGATA, Hirohisa, NAGATA, Tetsuya, NAKAJIMA, Tadashi, NAOTO, Kobayashi, NISHI, Ryoichi, NODA, Atsushi, OKAMOTO, Atsushi, OKAMOTO, Yoshiko K., OMUKAI, Kazuyuki, ONAKA, Takashi, OOTSUBO, Takafumi, OUCHI, Masami, SAITO, Hirobumi, SATO, Yoichi, SAKO, Shigeyuki, SEKIGUCHI, Tomohiko, SHIBAI, Hiroshi, SUGITA, Hiroyuki, SUGITANI, Koji, SUSA, Hajime, PYO, Tae-Soo, TAMURA, Motohide, UEDA, Yoshihiro, UENO, Munetaka, WADA, Takehiko, WATANABE, Jun'Ichi, YAMADA, Toru, YAMAMURA, Issei, YOSHIDA, Naoki, YOSHIMI, Kitamura, YUI, Yukari, BENEDETTINI, Milena, CERULLI, Riccardo, DI GIORGIO, Anna, MOLINARI, Sergio, ORFEI, Renato, PEZZUTO, Stefano, PIAZZO, Lorenzo, SARACENO, Paolo, SPINOGLIO, Luigi, DE GRAAUW, Thijs, DE KORTE, Piet, HELMICH, Frank, HOEVERS, Henk, HUISMAN, Robert, SHIPMAN, Russell, VAN DER TAK, Floris, VAN DER WERF, Paul, WILD, Wolfgang, ACOSTA-PULIDO, Jose, CERNICHARO, Jose, HERREROS, Jose, MARTIN-PINTADO, Jesus, NAJARRO, Francisco, PEREZ-FOURMON, Ismael, RAMON PARDO, Juan, GOMEZ, Francisca, CASTRO RODRIGUEZ, Nieves, ADE, Peter, BARLOW, Mike, CLEMENTS, David, FERLET, Marc, FRASER, Helen, GRIFFIN, Douglas, GRIFFIN, Matthew, HARGRAVE, Peter, ISAAK, Kate, IVISON, Robert, MANSOUR, Malik, LANIESSE, Jonathan, MAUSKOPF, Phillip, MOROZOV, Dmitry, OLIVER, Seb, ORLANDO, Angiola, PAGE, Mathew, POPESCU, Cristina, SERJEANT, Stephen, SUDIWALA, Rashmi, RIGOPOULOU, Dimitra, WALKER, Ian, WHITE, Glenn, VITI, Serena, WINTER, Berend, BOCK, Jamie, BRADFORD, Matt, HARWIT, Martin, HOLMES, Warren, Institut Méditerranéen d'Ecologie et de Paléoécologie (IMEP), Université Paul Cézanne - Aix-Marseille 3-Centre National de la Recherche Scientifique (CNRS)-Avignon Université (AU)-Université de Provence - Aix-Marseille 1, Institute of Atomic Physics, Université de Roumanie, Groundwater Tracing Unit, Department of Geological Sciences, School of Environmental Sciences [Norwich], University of East Anglia [Norwich] (UEA), Institut de Recherche en Immunologie et en Cancérologie [UdeM-Montréal] (IRIC), Université de Montréal (UdeM), Department of Zoology, University of Otago [Dunedin, Nouvelle-Zélande], Transplantation Biology Group, Imperial College London, Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire de Paris - Site de Paris (OP), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS), FORMATION STELLAIRE 2009, Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB), Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Radioastronomie (LRA), Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Processus mentaux et activation cérébrale, Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-IFR19-Institut National de la Santé et de la Recherche Médicale (INSERM), IFR des neurosciences de Lyon (IFNL), Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre Hospitalier le Vinatier [Bron]-Hospices Civils de Lyon (HCL)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon, Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, British Antarctic Survey (BAS), Natural Environment Research Council (NERC), Department of Radio and Space Science [Göteborg], Chalmers University of Technology [Göteborg], Laboratoire Astrophysique de Toulouse-Tarbes (LATT), Centre National de la Recherche Scientifique (CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Services communs OMP (UMS 831), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Solar Influences Data Analysis Center [Brussels] (SIDC), Royal Observatory of Belgium [Brussels] (ROB), Propriétés Optiques des Matériaux et Applications (POMA), Centre National de la Recherche Scientifique (CNRS)-Université d'Angers (UA), Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies (UMR 6174) (FEMTO-ST), Université de Technologie de Belfort-Montbeliard (UTBM)-Ecole Nationale Supérieure de Mécanique et des Microtechniques (ENSMM)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS), Observatoire Astronomique de Marseille Provence (OAMP), Université de Provence - Aix-Marseille 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Department of Physiology, The University of Hong Kong (HKU), School of Environmental Systems Engineering (SESE), The University of Western Australia (UWA), Centre for Water Research (CWR), Macaulay Institute, Centre Science des Matériaux et des Structures (SMS-ENSMSE), École des Mines de Saint-Étienne (Mines Saint-Étienne MSE), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Département Mécanique et Procédés d'Elaboration (MPE-ENSMSE), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-SMS, Department of Obstetrics and Gynecology [Stanford], Stanford Medicine, Stanford University-Stanford University, Korea Astronomy and Space Science Institute (KASI), Okayama University, Jack Baskin School of Engineering (UCSC), University of California [Santa Cruz] (UCSC), University of California-University of California, Adobe Systems Inc. (Adobe Advanced Technology Labs), Adobe Systems Inc., Defence Evaluation and Research Agency (DERA), Ministry of Defence (UK) (MOD)-Propulsion and Performance Department, Centre for Air Transport and the Environment (CATE), Manchester Metropolitan University (MMU), Department of Chemistry, Williams Hall-Kent State University, School of Earth and Atmospheric Sciences [Atlanta], Georgia Institute of Technology [Atlanta], Department of Earth and Planetary Sciences [Kobe], Kobe University, National Institute of Agro-Environmental Sciences (NIAES), Department of Earth System Science and Technology [Fukuoka] (ESST), Kyushu University [Fukuoka], Tokyo Institute of Technology [Tokyo] (TITECH), Department of Information and Communication Engineering, Graduate School of Information Science and Technology-The University of Tokyo (UTokyo), Department of Physics and Earth Sciences, University of the Ryukyus [Okinawa], Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Center for Climate System Research [Kashiwa] (CCSR), The University of Tokyo (UTokyo), School of Humanities [Univ of Toyama], University of Toyama, Department of Mechanical System (Hiroshima University), Hiroshima University, High Temperature Plasma Center [Tokyo], Discrete Optimization Laboratory, Toyohashi University of Technology, Hatakeyama Laboratory, University of Electro-Communications [Tokyo] (UEC)-Tohoku University [Sendai], Institute of Industrial Science (IIS), Institut de génétique et biologie moléculaire et cellulaire (IGBMC), Université Louis Pasteur - Strasbourg I-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Science and Technology Research Center (MCC), Mitsubishi Chemical Corporation, Institute for Solid State Physics [Tokyo] (ISSP), University of Electro-Communications [Tokyo] (UEC), Faculty of Science and Engineering [Waseda], Waseda University, Department of Civil Engineering, Chuo University (Chuo University), Frontier Collaborative Research Center (FCRC), Istituto di Fisica dello Spazio Interplanetario (IFSI), Consiglio Nazionale delle Ricerche (CNR), Antarctic Research a European Network for Astrophysics (ARENA), Institut de biologie et chimie des protéines [Lyon] (IBCP), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), SRON Netherlands Institute for Space Research (SRON), Max-Planck-Institut für Radioastronomie (MPIFR), Departamento de Astrofísica Molecular e Infrarroja (DAMIR), Instituto de Estructura de la Materia (IEM), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)-Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Centro de Investigaciones Biológicas (CSIC), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Laboratoire d'océanographie et de biogéochimie (LOB), Université de la Méditerranée - Aix-Marseille 2-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Ecosystèmes Littoraux et Cotiers, Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS), Royal Observatory Edinburgh (ROE), University of Edinburgh, Processus d'Activation Sélective par Transfert d'Energie Uni-électronique ou Radiatif (UMR 8640) (PASTEUR), Université Pierre et Marie Curie - Paris 6 (UPMC)-Département de Chimie - ENS Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Ecole Supérieure des Affaires (ESA), Université Pierre Mendès France - Grenoble 2 (UPMF), Service de Neurologie [CHU Pitié-Salpêtrière], IFR70-CHU Pitié-Salpêtrière [AP-HP], Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Neurologie et thérapeutique expérimentale, Institut National de la Santé et de la Recherche Médicale (INSERM)-IFR70-Université Pierre et Marie Curie - Paris 6 (UPMC), Department of Physics, University of Wales, Engineering Department, University of Cambridge [UK] (CAM), SLAC National Accelerator Laboratory (SLAC), Stanford University, Université Paul Cézanne - Aix-Marseille 3-Université de Provence - Aix-Marseille 1-Avignon Université (AU)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université de Lyon-Université de Lyon-Hospices Civils de Lyon (HCL)-Centre Hospitalier le Vinatier [Bron]-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université d'Angers (UA)-Centre National de la Recherche Scientifique (CNRS), Université de Technologie de Belfort-Montbeliard (UTBM)-Ecole Nationale Supérieure de Mécanique et des Microtechniques (ENSMM)-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), University of California [Santa Cruz] (UC Santa Cruz), University of California (UC)-University of California (UC), Kyushu University, Waseda University [Tokyo, Japan], National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Université Pierre et Marie Curie - Paris 6 (UPMC)-IFR70-Institut National de la Santé et de la Recherche Médicale (INSERM), Institut de Recherche en Immunologie et en Cancérologie (IRIC), Université de Montréal [Montréal], PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS), École normale supérieure - Paris (ENS Paris)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université de Cergy Pontoise (UCP), Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Services communs OMP - UMS 831 (UMS 831), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Toulouse III - Paul Sabatier (UT3), Royal Observatory of Belgium [Brussels], Université de Franche-Comté (UFC)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Mécanique et des Microtechniques (ENSMM)-Université de Technologie de Belfort-Montbeliard (UTBM), Division of Reproductive Biology, Stanford University [Stanford], Okayama University [Okayama], Graduate School of Information Science and Technology-The University of Tokyo, The University of Tokyo, Department of linguistic [Toyama], Consejo Superior de Investigaciones Científicas [Spain] (CSIC)-Consejo Superior de Investigaciones Científicas [Spain] (CSIC), Consejo Superior de Investigaciones Científicas [Spain] (CSIC), École normale supérieure - Paris (ENS Paris)-École normale supérieure - Paris (ENS Paris)-Centre National de la Recherche Scientifique (CNRS), Service de neurologie 1 [CHU Pitié-Salpétrière], Assistance publique - Hôpitaux de Paris (AP-HP) (APHP)-CHU Pitié-Salpêtrière [APHP], Stanford Linear Accelerator Center (SLAC), Astronomy, Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Université Fédérale Toulouse Midi-Pyrénées-Météo-France -Institut de Recherche pour le Développement (IRD)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), The University of Tokyo (UTokyo)-Graduate School of Information Science and Technology, Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-CHU Pitié-Salpêtrière [AP-HP], and Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Sorbonne Université (SU)
Subjects: [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Infrared telescope, UNIVERSE, Astrophysics, Spica, Astrophysics::Cosmology and Extragalactic Astrophysics, POLYCYCLIC AROMATIC-HYDROCARBON, 7. Clean energy, 01 natural sciences, Space missions, Cosmology, Space exploration, law.invention, STAR-FORMATION, 010309 optics, Telescope, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Spitzer Space Telescope, law, 0103 physical sciences, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Physics, Infrared astronomy, SPECTRUM, Spacecraft, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], SUBMILLIMETER GALAXIES, business.industry, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Astronomy and Astrophysics, MODEL, SPITZER, PAHS, Space and Planetary Science, Infrared, Physics::Space Physics, IR, Astrophysics::Earth and Planetary Astrophysics, business, EMISSION
Abstract: International audience; The Space Infrared telescope for Cosmology and Astrophysics (SPICA) is planned to be the next space astronomy mission observing in the infrared. The mission is planned to be launched in 2017 and will feature a 3.5 m telescope cooled to 30 microns wavelength). We describe the scientific advances that will be made possible by this large increase in sensitivity and give details of the mission, spacecraft and focal plane conceptual design.
Published: 2009

26. Benchmarking PDR models against the Horsehead edge

Author: Pety, J., Goicoechea, J. R., Gerin, M., Hily-Blant, Pierre, Teyssier, D., Roueff, E., Habart, E., Abergel, A., Institut de RadioAstronomie Millimétrique (IRAM), Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), European Space Astronomy Centre (ESAC), European Space Agency (ESA), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS Paris)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université de Cergy Pontoise (UCP), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Pety, Jérôme, École normale supérieure - Paris (ENS-PSL), Agence Spatiale Européenne = European Space Agency (ESA), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), and Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES)
Subjects: [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], [PHYS.ASTR.CO] Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Astrophysics (astro-ph), FOS: Physical sciences, [SDU.ASTR] Sciences of the Universe [physics]/Astrophysics [astro-ph], Astrophysics
Abstract: To prepare for the unprecedented spatial and spectral resolution provided by ALMA and Herschel/HIFI, chemical models are being benchmarked against each other. It is obvious that chemical models also need well-constrained observations that can serve as references. Photo-dissociation regions (PDRs) are particularly well suited to serve as references because they make the link between diffuse and molecular clouds, thus enabling astronomers to probe a large variety of physical and chemical processes. At a distance of 400 pc (1" corresponding to 0.002 pc), the Horsehead PDR is very close to the prototypical kind of source (i.e. 1D, edge-on) needed to serve as a reference to models., Comment: 4 pages, 2 PostScript figures. To appear in the proceedings of "SF2A-2006: Semaine de l'Astrophysique Francaise", SF2A, 2006 (D. Barret, F. Casoli, T. Contini, G. Lagache, A. Lecavelier, and L. Pagani eds). Uses LaTeX2e
Published: 2006
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27. Kinematics of the ionized-to-neutral interfaces in Monoceros R2.

Author: Pilleri, P., Fuente, A., Gerin, M., Cernicharo, J., Goicoechea, J. R., Ossenkopf, V., Joblin, C., González-García, M., Treviño-Morales, S. P., Sánchez-Monge, Á., Pety, J., Berné, O., and Kramer, C.
Subjects: IONIZED gases, ABSORPTION spectra, MOLECULAR spectroscopy, ASTROPHYSICS
Abstract: Context. Monoceros R2 (Mon R2), at a distance of 830 pc, is the only ultra-compact Hii region (UC Hii) where its associated photon-dominated region (PDR) can be resolved with the Herschel Space Observatory. Aims. Our aim is to investigate observationally the kinematical patterns in the interface regions (i.e., the transition from atomic to molecular gas) associated with Mon R2. Methods. We used the HIFI instrument on board Herschel to observe the line profiles of the reactive ions CH+, OH+, and H2 O+ toward different positions in Mon R2. We derive the column density of these molecules and compare them with gas-phase chemistry models. Results. The reactive ion CH+ is detected both in emission (at central and red-shifted velocities) and in absorption (at blue-shifted velocities). The OH+ ion is detected in absorption at both blue- and red-shifted velocities, with similar column densities; H2O+ is not detected at any of the positions, down to a rms of 40 mK toward the molecular peak. At this position, we find that the OH+ absorption originates in a mainly atomicmedium, and therefore is associated with the most exposed layers of the PDR. These results are consistent with the predictions from photo-chemical models. The line profiles are consistent with the atomic gas being entrained in the ionized gas flow along the walls of the cavity of the Hii region. Based on this evidence, we are able to propose a new geometrical model for this region. Conclusions. The kinematical patterns of the OH+ and CH+ absorption indicate the existence of a layer of mainly atomic gas for which we have derived, for the first time, some physical parameters and its dynamics. [ABSTRACT FROM AUTHOR]
Published: 2014
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28. OH far-infrared emission from low- and intermediate-mass protostars surveyed with Herschel-PACS.

Author: Wampfler, S. F., Bruderer, S., Karska, A., Herczeg, G. J., van Dishoeck, E. F., Kristensen, L. E., Goicoechea, J. R., Benz, A. O., Doty, S. D., McCoey, C., Baudry, A., Giannini, T., and Larsson, B.
Subjects: WATER chemistry, STREAM chemistry, PROTOSTARS, ASTRONOMY, ASTROPHYSICS
Abstract: Context. The OH radical is a key species in the water chemistry network of star-forming regions, because its presence is tightly related to the formation and destruction of water. Previous studies of the OH far-infrared emission from low- and intermediate-mass protostars suggest that the OH emission mainly originates from shocked gas and not from the quiescent protostellar envelopes. Aims. We aim to study the excitation of OH in embedded low- and intermediate-mass protostars, determine the influence of source parameters on the strength of the emission, investigate the spatial extent of the OH emission, and further constrain its origin. Methods. This paper presents OH observations from 23 low- and intermediate-mass young stellar objects obtained with the PACS integral field spectrometer on-board Herschel in the context of the "Water In Star-forming regions with Herschel" (WISH) key program. Radiative transfer codes are used to model the OH excitation. Results. Most low-mass sources have compact OH emission (≲5000 AU scale), whereas the OH lines in most intermediate-mass sources are extended over the whole 47."0 × 47."0 PACS detector field-of-view (≳20 000 AU). The strength of the OH emission is correlated with various source properties such as the bolometric luminosity and the envelope mass, but also with the [OI] and H2O emission. Rotational diagrams for sources with many OH lines show that the level populations of OH can be approximated by a Boltzmann distribution with an excitation temperature at around 70 K. Radiative transfer models of spherically symmetric envelopes cannot reproduce the OH emission fluxes nor their broad line widths, strongly suggesting an outflow origin. Slab excitation models indicate that the observed excitation temperature can either be reached if the OH molecules are exposed to a strong far-infrared continuum radiation field or if the gas temperature and density are sufficiently high. Using realistic source parameters and radiation fields, it is shown for the case of Ser SMM1 that radiative pumping plays an important role in transitions arising from upper level energies higher than 300 K. The compact emission in the low-mass sources and the required presence of a strong radiation field and/or a high density to excite the OH molecules points toward an origin in shocks in the inner envelope close to the protostar. [ABSTRACT FROM AUTHOR]
Published: 2013
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29. Water in star-forming regions with Herschel (WISH).

Author: Karska, A., Herczeg, G. J., van Dishoeck, E. F., Wampfler, S. F., Kristensen, L. E., Goicoechea, J. R., Visser, R., Nisini, B., José-García, I. San, Bruderer, S., Śniady, P., Doty, S., Fedele, D. D., Yıldız, U. A., Benz, A. O., Bergin, E., Caselli, P., Herpin, F., Hogerheijde, M. R., and Johnstone, D.
Subjects: STAR formation, SPECTRAL energy distribution, PROTOSTARS, ASTRONOMY, ASTROPHYSICS
Abstract: Context. Understanding the physical phenomena involved in the earlierst stages of protostellar evolution requires knowledge of the heating and cooling processes that occur in the surroundings of a young stellar object. Spatially resolved information from its constituent gas and dust provides the necessary constraints to distinguish between different theories of accretion energy dissipation into the envelope. Aims. Our aims are to quantify the far-infrared line emission from low-mass protostars and the contribution of different atomic and molecular species to the gas cooling budget, to determine the spatial extent of the emission, and to investigate the underlying excitation conditions. Analysis of the line cooling will help us characterize the evolution of the relevant physical processes as the protostar ages. Methods. Far-infrared Herschel-PACS spectra of 18 low-mass protostars of various luminosities and evolutionary stages are studied in the context of the WISH key program. For most targets, the spectra include many wavelength intervals selected to cover specific CO, H2O, OH, and atomic lines. For four targets the spectra span the entire 55-200 μm region. The PACS field-of-view covers ~47" with the resolution of 9.4". Results. Most of the protostars in our sample show strong atomic and molecular far-infrared emission. Water is detected in 17 out of 18 objects (except TMC1A), including 5 Class I sources. The high-excitation H2O 818-707 63.3 μm line (Eu/kB = 1071 K) is detected in 7 sources. CO transitions from J = 14-13 up to J = 49-48 are found and show two distinct temperature components on Boltzmann diagrams with rotational temperatures of ~350 K and ~700 K. H2O has typical excitation temperatures of ~150 K. Emission from both Class 0 and I sources is usually spatially extended along the outflow direction but with a pattern that depends on the species and the transition. In the extended sources, emission is stronger off source and extended on ⩾10 000 AU scales; in the compact sample, more than half of the flux originates within 1000 AU of the protostar. The H2O line fluxes correlate strongly with those of the high-J CO lines, both for the full array and for the central position, as well as with the bolometric luminosity and envelope mass. They correlate less strongly with OH fluxes and not with [Oi] fluxes. In contrast, [Oi] andOH often peak together at the central position. Conclusions. The PACS data probe at least two physical components. The H2O and CO emission very likely arises in non-dissociative (irradiated) shocks along the outflow walls with a range of pre-shock densities. Some OH is also associated with this component, most likely resulting from H2O photodissociation. UV-heated gas contributes only a minor fraction to the CO emission observed by PACS, based on the strong correlation between the shock-dominated CO 24-23 line and the CO 14-13 line. [OI] and some of the OH emission probe dissociative shocks in the inner envelope. The total far-infrared cooling is dominated by H2O and CO, with the fraction contributed by [OI] increasing for Class I sources. Consistent with previous studies, the ratio of total far-infrared line emission over bolometric luminosity decreases with the evolutionary state. [ABSTRACT FROM AUTHOR]
Published: 2013
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30. The complete far-infrared and submillimeter spectrum of the Class 0 protostar Serpens SMM1 obtained with Herschel: Characterizing UV-irradiated shocks heating and chemistry.

Author: Goicoechea, J. R., Cernicharo, J., Karska, A., Herczeg, G. J., Polehampton, E. T., Wampfler, S. F., Kristensen, L. E., van Dishoeck, E. F., Etxaluze, M., Berné, O., and Visser, R.
Subjects: *PROTOSTARS, *INFRARED spectra, *SPECTRUM analysis, *ASTROPHYSICS, *ULTRAVIOLET radiation
Abstract: We present the first complete ∼55-671 μm spectral scan of a low-mass Class 0 protostar (Serpens SMM1) taken with the PACS and SPIRE spectrometers onboard Herschel. More than 145 lines have been detected, most of them rotationally excited lines of 12CO (full ladder from Ju = 4-3 to 42-41 and Eu/k = 4971 K), H2O (up to 818-707 and Eu/k = 1036 K), OH (up to 2⨅1/2 J = 7/2-5/2 and Eu/k = 618 K), 13CO (up to Ju = 16-15), HCN and HCO+ (up to Ju = 12-11). Bright [OI]63, 145 μm and weaker [C II]158 and [C I]370, 609 μm lines are also detected, but excited lines from chemically related species (NH3, CH+, CO+, OH+ or H2O+) are not. Mid-infrared spectra retrieved from the Spitzer archive are also first discussed here. The ∼10-37 μm spectrum has many fewer lines, but shows clear detections of [Ne II], [Fe II], [Si II] and [S I] fine structure lines, as well as weaker H2 S(1) and S(2) pure rotational lines. The observed line luminosity is dominated by CO (∼54%), H2O (∼22%), [OI] (∼12%) and OH (∼9%) emission. A multi-component radiative transfer model allowed us to approximately quantify the contribution of the three different temperature components suggested by the 12CO rotational ladder (Thot k ≈ 800 K, Twarm k ≈ 375 K and Tcool k ≈ 150 K). Gas densities n(H2) ∼ 5 × 106 cm-3 are needed to reproduce the observed far-IR lines arising from shocks in the inner protostellar envelope (warm and hot components) for which we derive upper limit abundances of x(CO) ≲ 10-4, x(H2O) ≲ 0.2 × 10-5 and x(OH) ≲ 10-6 with respect to H2. The lower energy submm 12CO and H2O lines show more extended emission that we associate with the cool entrained outflow gas. Fast dissociative Jshocks (vs > 60 km s-1) within an embedded atomic jet, as well as lower velocity small-scale non-dissociative shocks (vs ≲ 20 km s-1) are needed to explain both the atomic fine structure lines and the hot CO and H2O lines respectively. Observations also show the signature of UV radiation (weak [CII] and [CI] lines and high HCO+/HCN abundance ratios) and thus, most observed species likely arise in UV-irradiated shocks. Dissociative J-shocks produced by a jet impacting the ambient material are the most probable origin of [OI] and OH emission and of a significant fraction of the warm CO emission. In addition, H2O photodissociation in UV-irradiated non-dissociative shocks along the outflow cavity walls can also contribute to the [OI] and OH emission. [ABSTRACT FROM AUTHOR]
Published: 2012
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31. The IRAM-30 m line survey of the Horsehead PDR: II. First detection of the l-C3H+ hydrocarbon cation.

Author: Pety, J., Gratier, P., Guzmán, V., Roueff, E., Gerin, M., Goicoechea, J. R., Bardeau, S., Sievers, A., Le Petit, F., Le Bourlot, J., Belloche, A., and Talbi, D.
Subjects: CATIONS, HYDROCARBONS, INTERSTELLAR medium, ASTROPHYSICS, GAUSSIAN processes
Abstract: Context. Pure gas-phase chemistry models do not succeed in reproducing the measured abundances of small hydrocarbons in the interstellar medium. Information on key gas-phase progenitors of these molecules sheds light on this problem. Aims. We aim to constrain the chemical content of the Horsehead mane with a millimeter unbiased line survey at two positions, namely the photo-dissociation region (PDR) and the nearby shielded core. This project revealed a consistent set of eight unidentified lines toward the PDR position. We associate them to the l-C3H+ hydrocarbon cation, which enables us to constrain the chemistry of small hydrocarbons. We observed the lowest detectable J line in the millimeter domain along a cut toward the illuminating direction to constrain the spatial distribution of the l-C3H+ emission perpendicular to the photo-dissociation front. Methods. We simultaneously fit 1) the rotational and centrifugal distortion constants of a linear rotor; and 2) the Gaussian line shapes located at the eight predicted frequencies. A rotational diagram is then used to infer the excitation temperature and the column density. We finally compare the abundance to the results of the Meudon PDR photochemical model. Results. Six out of the eight unidentified lines observable in the millimeter bands are detected with a signal-to-noise ratio from 6 to 19 toward the Horsehead PDR, while the two last ones are tentatively detected. Mostly noise appears at the same frequency toward the dense core, located less than 40'' away. Moreover, the spatial distribution of the species integrated emission has a shape similar to radical species such as HCO, and small hydrocarbons such as C2H, which show enhanced abundances toward the PDR. The observed lines can be accurately fitted with a linear rotor model, implying a 1Σ ground electronic state. The deduced rotational constant value is B = 11 244.9512 ± 0.0015 MHz, close to that of l-C3H. Conclusions. This is the first detection of the l-C3H+ hydrocarbon in the interstellar medium. Laboratory spectroscopy is underway to confirm these results. Interferometric imaging is needed to firmly constrain the small hydrocarbon chemistry in the Horsehead. [ABSTRACT FROM AUTHOR]
Published: 2012
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32. The IRAM-30m line survey of the Horsehead PDR I. CF+ as a tracer of C+ and as a measure of the fluorine abundance.

Author: Guzmán, V., Pety, J., Gratier, P., Goicoechea, J. R., Gerin, M., Roueff, E., and Teyssier, D.
Subjects: FLUORINE, INTERSTELLAR medium, ASTROPHYSICS, NEBULAE, GALAXIES
Abstract: C+ is a key species in the interstellar medium, but its 158 μm fine structure line cannot be observed from ground-based telescopes. Current models of fluorine chemistry predict that CF+ is the second-most important fluorine reservoir in regions where C+ is abundant. We detected the J = 1-0 and J = 2-1 rotational lines of CF+ with high signal-to-noise ratio toward the photo-dissociation region and dense core positions in the Horsehead. Using a rotational diagram analysis, we derive a column density of N(CF+) = (1.5-2.0) × 1012 cm-2. Because of the simple fluorine chemistry, the CF+ column density is proportional to the fluorine abundance. We thus infer the fluorine gas-phase abundance to be F/H = (0.6-1.5) × 10-8. Photochemical models indicate that CF+ is found in the layers where C+ is abundant. The emission arises in the UV-illuminated skin of the nebula, tracing the outermost cloud layers. Indeed, CF+ and C+ are the only species observed to date in the Horsehead with a double-peaked line profile caused by kinematics. We therefore propose that CF+, which is detectable from the ground, can be used as a proxy of the C+ layers. [ABSTRACT FROM AUTHOR]
Published: 2012
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33. HERSCHEL SURVEY OF GALACTIC OH+, H2O+, AND H3O+: PROBING THE MOLECULAR HYDROGEN FRACTION AND COSMIC-RAY IONIZATION RATE.

Author: Indriolo, Nick, Neufeld, D. A., Gerin, M., Schilke, P., Benz, A. O., Winkel, B., Menten, K. M., Chambers, E. T., Black, John H., Bruderer, S., Falgarone, E., Godard, B., Goicoechea, J. R., Gupta, H., Lis, D. C., Ossenkopf, V., Persson, C. M., Sonnentrucker, P., van der Tak, F. F. S., and van Dishoeck, E. F.
Subjects: INTERSTELLAR medium, ATOMIC hydrogen, COSMIC rays, ASTROCHEMISTRY, ASTROPHYSICS
Abstract: In diffuse interstellar clouds the chemistry that leads to the formation of the oxygen-bearing ions OH+, H2O+, and H3O+ begins with the ionization of atomic hydrogen by cosmic rays, and continues through subsequent hydrogen abstraction reactions involving H2. Given these reaction pathways, the observed abundances of these molecules are useful in constraining both the total cosmic-ray ionization rate of atomic hydrogen (ζH) and molecular hydrogen fraction (). We present observations targeting transitions of OH+, H2O+, and H3O+ made with the Herschel Space Observatory along 20 Galactic sight lines toward bright submillimeter continuum sources. Both OH+ and H2O+ are detected in absorption in multiple velocity components along every sight line, but H3O+ is only detected along 7 sight lines. From the molecular abundances we compute in multiple distinct components along each line of sight, and find a Gaussian distribution with mean and standard deviation 0.042 ± 0.018. This confirms previous findings that OH+ and H2O+ primarily reside in gas with low H2 fractions. We also infer ζH throughout our sample, and find a lognormal distribution with mean log (ζH) = –15.75 (ζH = 1.78 × 10–16 s–1) and standard deviation 0.29 for gas within the Galactic disk, but outside of the Galactic center. This is in good agreement with the mean and distribution of cosmic-ray ionization rates previously inferred from H observations. Ionization rates in the Galactic center tend to be 10-100 times larger than found in the Galactic disk, also in accord with prior studies. [ABSTRACT FROM AUTHOR]
Published: 2015
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34. CHEMICAL ANALYSIS OF A DIFFUSE CLOUD ALONG A LINE OF SIGHT TOWARD W51: MOLECULAR FRACTION AND COSMIC-RAY IONIZATION RATE

Author: Goicoechea, J [Departamento de Astrofisica, Centro de Astrobiologia (CSIC-INTA), E-28850 Madrid (Spain)]
Published: 2012
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34 results on '"GOICOECHEA, J."'

1. Using SPICA Space Telescope to characterize Exoplanets

2. Physical parameters for Orion KL from modelling its ISO high resolution far-IR CO line spectrum

3. Sulfur chemistry in the Horsehead. An interferometric view of the Horsehead PDR

4. Molecular survey of CRL618

5. The ISO LWS high resolution spectral survey towards Sagittarius B2

6. Far-Infrared detection of H2D+ toward Sgr B2

7. The Water Vapor Abundance in Orion KL Outflows

8. Low sulfur depletion in the Horsehead PDR

9. A far-infrared molecular and atomic line survey of the Orion KL region

10. Water Vapor around Sgr B2

11. Observational evidence of the formation of cyanopolyynes in CRL618 through the polimerization of HCN

12. The slowly expanding envelope of CRL618 probed with HC3N rotational ladders

13. The far-IR spectrum of Sagittarius B2 region: Extended molecular absorption, photodissociation and photoionization

14. Extended photoionization and photodissociation in Sgr B2

15. A new infrared band in the Interstellar and Circumstellar Clouds: C_4 or C_4H?

16. Far-Infrared OH fluorescent emission in Sagittarius B2

17. Chemical Evolution of the Circumstellar Envelopes of Carbon-rich Post-AGB objects

18. Water in star-forming regions: Physics and chemistry from clouds to disks as probed by Herschel spectroscopy

19. Origins space telescope: from first light to life.

20. HERSCHEL SURVEY OF GALACTIC OH + , H 2 O + , AND H 3 O + : PROBING THE MOLECULAR HYDROGEN FRACTION AND COSMIC-RAY IONIZATION RATE

21. Herschel spectral-mapping of the Helix Nebula (NGC 7293): Extended CO photodissociation and OH+ emission

22. The WADI key project: New insights to photon-dominated regions from Herschel observations

23. A high-resolution line survey of IRC+10216 with Herschel/HIFI. First results: Detection of warm silicon dicarbide (SiC2)

24. Hydrides in Young Stellar Objects: Radiation tracers in a protostar-disk-outflow system

25. The space infrared telescope for cosmology and astrophysics: SPICA A joint mission between JAXA and ESA

26. Benchmarking PDR models against the Horsehead edge

27. Kinematics of the ionized-to-neutral interfaces in Monoceros R2.

28. OH far-infrared emission from low- and intermediate-mass protostars surveyed with Herschel-PACS.

29. Water in star-forming regions with Herschel (WISH).

30. The complete far-infrared and submillimeter spectrum of the Class 0 protostar Serpens SMM1 obtained with Herschel: Characterizing UV-irradiated shocks heating and chemistry.

31. The IRAM-30 m line survey of the Horsehead PDR: II. First detection of the l-C3H+ hydrocarbon cation.

32. The IRAM-30m line survey of the Horsehead PDR I. CF+ as a tracer of C+ and as a measure of the fluorine abundance.

33. HERSCHEL SURVEY OF GALACTIC OH+, H2O+, AND H3O+: PROBING THE MOLECULAR HYDROGEN FRACTION AND COSMIC-RAY IONIZATION RATE.

34. CHEMICAL ANALYSIS OF A DIFFUSE CLOUD ALONG A LINE OF SIGHT TOWARD W51: MOLECULAR FRACTION AND COSMIC-RAY IONIZATION RATE

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34 results on '"GOICOECHEA, J."'

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