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1. Living with Parkinson’s disease: disease and medication experiences of patients and caregivers

Author

Yi-Wen Chen, Chu-Yun Huang, Jo-Hsin Chen, Chi-Lien Hsiao, Chien-Tai Hong, Chen-Yu Wu, and Elizabeth H. Chang

Subjects
parkinson’s disease, medication therapy, patient, caregiver, qualitative research, medication experience, Medicine (General), R5-920
Abstract

Purpose Symptoms and medication use in patients with Parkinson’s disease (PD) affect the quality of life of patients and caregivers, yet prior research seldom focused on their experiences with medications. This study explored comprehensive living and medication experience from patients with PD and their caregivers. Methods Patients diagnosed with PD for ≥2 years, with or without their caregivers, were recruited from an outpatient clinic in Taiwan. Semi-structured in-depth interviews were conducted based on the Common Sense Model. A qualitative content analysis was used to identify salient themes from verbatim transcripts. Results In total, 15 patients and eight caregivers were interviewed. Five themes were derived: (1) symptoms and help-seeking behaviours before a diagnosis, (2) emotional impacts and life adaptations after a PD diagnosis, (3) life affected by medications, (4) experiences of caregivers in taking care of PD patients, and (5) communication between doctors and patients. Conclusions Patients frequently adjusted their daily schedules to live with PD and the medication side effects. Caregivers struggle to overcome caring burdens and to stay positive to support patients. More attention on providing medication information, mental support, and communication between stakeholders is needed to improve the quality of life of patients and caregivers.

Published
2022
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2. Herschel HIFI observations of O2toward Orion: Special conditions for shock enhanced emission

Author

Pierre Encrenaz, Arnold O. Benz, John H. Black, Åke Hjalmarson, Serena Viti, Dariusz C. Lis, Jo-Hsin Chen, David A. Neufeld, Paul F. Goldsmith, Ewine F. van Dishoeck, Laurent Pagani, David Hollenbach, Edith Falgarone, Floris van der Tak, Umut A. Yildiz, Gary J. Melnick, Paola Caselli, Michael J. Kaufman, Edwin A. Bergin, Ronald L. Snell, Javier R. Goicoechea, Jet Propulsion Laboratory (JPL), California Institute of Technology (CALTECH)-NASA, 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), Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University [Cambridge]-Smithsonian Institution, Onsala Space Observatory (OSO), Chalmers University of Technology [Göteborg], INAF - Osservatorio Astrofisico di Arcetri (OAA), Istituto Nazionale di Astrofisica (INAF), SRON Netherlands Institute for Space Research (SRON), Leiden Observatory [Leiden], Universiteit Leiden [Leiden], Astronomy, NASA-California Institute of Technology (CALTECH), École normale supérieure - Paris (ENS-PSL), Harvard University-Smithsonian Institution, and Universiteit Leiden

Subjects
010504 meteorology & atmospheric sciences, media_common.quotation_subject, Interstellar cloud, FOS: Physical sciences, Flux, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Radiation, 01 natural sciences, 7. Clean energy, law.invention, Shock waves, law, 0103 physical sciences, Maser, 010303 astronomy & astrophysics, molecules [ISM], ComputingMilieux_MISCELLANEOUS, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, media_common, Line (formation), Astrochemistry, [PHYS]Physics [physics], Physics, Line-of-sight, Molecular cloud, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, ISM: molecules, 13. Climate action, Space and Planetary Science, Sky, Astrophysics of Galaxies (astro-ph.GA), [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

We report observations of molecular oxygen (O$_2$) rotational transitions at 487 GHz, 774 GHz, and 1121 GHz toward Orion Peak A. The O2 lines at 487 GHz and 774 GHz are detected at velocities of 10-12 km/s with line widths 3 km/s; however, the transition at 1121 GHz is not detected. The observed line characteristics, combined with the results of earlier observations, suggest that the region responsible for the O$_2$ emission is 9" (6e16 cm) in size, and is located close to the H2 Peak 1position (where vibrationally-excited H$_2$ emission peaks), and not at Peak A, 23" away. The peak O2 column density is 1.1e18/cm2. The line velocity is close to that of 621 GHz water maser emission found in this portion of the Orion Molecular Cloud, and having a shock with velocity vector lying nearly in the plane of the sky is consistent with producing maximum maser gain along the line-of-sight. The enhanced O$_2$ abundance compared to that generally found in dense interstellar clouds can be explained by passage of a low-velocity C-shock through a clump with preshock density 2e4/cm3, if a reasonable flux of UV radiation is present. The postshock O$_2$ can explain the emission from the source if its line of sight dimension is ~10 times larger than its size on the plane of the sky. The special geometry and conditions required may explain why O$_2$ emission has not been detected in the cores of other massive star-forming molecular clouds., 28 pages, 13 figures

Published
2014

3. Herschel observations of EXtraordinary Sources: Analysis of the full Herschel/HIFI molecular line survey of Sagittarius B2(N)

Author

Edwin A. Bergin, Shanshan Yu, Thomas G. Phillips, Trevor D. McNeill, Peter Schilke, Cécile Favre, Justin L. Neill, Claudia Comito, Martin Emprechtinger, Amanda L. Steber, Dariusz C. Lis, Raquel Monje, Andrew M. Burkhardt, Brent J. Harris, Brett A. McGuire, Dana E. Anderson, Sheng-Li Qin, Steven D. Lord, Jo Hsin Chen, Tatiana Vasyunina, Nathan R. Crockett, Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University [Cambridge]-Smithsonian Institution, I. Physikalisches Institut [Köln], Universität zu Köln, Equipe de Recherche en Ingénierie des Connaissances (ERIC), Université Lumière - Lyon 2 (UL2), Laboratoire de Cosmologie, Astrophysique Stellaire & Solaire, de Planétologie et de Mécanique des Fluides (CASSIOPEE), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), CalTech-CSO (CSO), and California Institute of Technology (CALTECH)

Subjects
Physics, [PHYS]Physics [physics], Spectral signature, Thermodynamic equilibrium, Resolution (electron density), FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics - Astrophysics of Galaxies, Wavelength, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Astrophysics::Solar and Stellar Astrophysics, Sagittarius B2, Isotopologue, Absorption (electromagnetic radiation), [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], ComputingMilieux_MISCELLANEOUS, Astrophysics::Galaxy Astrophysics, Line (formation)
Abstract

A sensitive broadband molecular line survey of the Sagittarius B2(N) star-forming region has been obtained with the HIFI instrument on the Herschel Space Observatory, offering the first high-spectral resolution look at this well-studied source in a wavelength region largely inaccessible from the ground (625-157 um). From the roughly 8,000 spectral features in the survey, a total of 72 isotopologues arising from 44 different molecules have been identified, ranging from light hydrides to complex organics, and arising from a variety of environments from cold and diffuse to hot and dense gas. We present an LTE model to the spectral signatures of each molecule, constraining the source sizes for hot core species with complementary SMA interferometric observations, and assuming that molecules with related functional group composition are cospatial. For each molecule, a single model is given to fit all of the emission and absorption features of that species across the entire 480-1910 GHz spectral range, accounting for multiple temperature and velocity components when needed to describe the spectrum. As with other HIFI surveys toward massive star forming regions, methanol is found to contribute more integrated line intensity to the spectrum than any other species. We discuss the molecular abundances derived for the hot core, where the local thermodynamic equilibrium approximation is generally found to describe the spectrum well, in comparison to abundances derived for the same molecules in the Orion KL region from a similar HIFI survey., Accepted to ApJ. 64 pages, 14 figures. Truncated abstract

Published
2014

4. Hypermethylation of miR-203 in endometrial carcinomas

Author

Chieh Ti Kuo, Jo Hsin Chen, Denise Uyar, Tim H M Huang, Janet S. Rader, Paul J. Goodfellow, and Yi-Wen Huang

Subjects
Oncology, medicine.medical_specialty, Uterine Cervical Neoplasms, Endometrium, Article, SOXC Transcription Factors, SOX4, Internal medicine, Cell Line, Tumor, microRNA, medicine, Biomarkers, Tumor, Humans, Promoter Regions, Genetic, Ovarian Neoplasms, business.industry, Endometrial cancer, Obstetrics and Gynecology, Microsatellite instability, DNA Methylation, medicine.disease, Endometrial Neoplasms, Gene Expression Regulation, Neoplastic, MicroRNAs, medicine.anatomical_structure, Case-Control Studies, DNA methylation, Cancer research, Carcinoma, Squamous Cell, Female, Microsatellite Instability, miR-203, business, Carcinoma, Endometrioid, Adenocarcinoma, Clear Cell
Abstract

Aberrant expression of SOX4 in endometrial cancer has been identified and partially was contributed to hypermethylation of miR-129-2. Other miRNAs are suspected to influence SOX 4 as well. The current study seeks to identify other hypermethylated miRNAs that regulate SOX4 in endometrial carcinomas.Methylation levels of miRNA promoter regions were measured by combined bisulfite restriction analysis (COBRA) and pyrosequencing assays. Gene expression was determined by RT-qPCR. Methylation level of a miRNA locus was corrected with clinicopathologic factors for 252 gynecological specimens.In silico analysis identified 13 miRNA loci bound on the 3'-UTR of SOX4. Using COBRA assays, increased methylation of miR-203, miR-219-2, miR-596, and miR-618 was detected in endometrial cancer cells relative to those seen in a normal cell line and in normal endometrium. Transfection of a miR-203 mimic decreased SOX4 gene expression. Hypermethylation of miR-203 was detected in 52% of type I endometrioid endometrial carcinomas (n=131) but was not seen in any of 10 uninvolved normal endometria (P0.001). Methylation status of miR-203 was significantly associated with microsatellite instability and MLH1 methylation in endometrial tumors (P0.001). Furthermore, hypermethylation of miR-203 was found in endometrioid and clear endometrial subtype tumors, but not in cervical squamous cell and ovarian carcinomas.Hypermethylation of miR-203 is a frequent event in endometrial carcinomas and is strongly associated with microsatellite instability and MLH1 methylation status. Thus, miR-203 methylation level might represent a marker for patients with endometrioid and clear endometrial sub-cancers.

Published
2014

5. Deep observations of O 2 toward a low-mass protostar with Herschel -HIFI

Author

Kinsuk Acharyya, René Liseau, Laurent Pagani, Eric Herbst, Paola Caselli, Gary J. Melnick, Umut A. Yildiz, Ruud Visser, Ewine F. van Dishoeck, Dariusz C. Lis, Maryvonne Gerin, Lars E. Kristensen, Edwin A. Bergin, Paul F. Goldsmith, Ronald L. Snell, Jo Hsin Chen, Jet Propulsion Laboratory (JPL), California Institute of Technology (CALTECH)-NASA, Leiden Observatory [Leiden], Universiteit Leiden [Leiden], Department of Radio and Space Science [Göteborg], Chalmers University of Technology [Göteborg], 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), Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University [Cambridge]-Smithsonian Institution, INAF - Osservatorio Astrofisico di Arcetri (OAA), Istituto Nazionale di Astrofisica (INAF), Department of Physics, Ohio State University [Columbus] (OSU), NASA-California Institute of Technology (CALTECH), Universiteit Leiden, École normale supérieure - Paris (ENS-PSL), and Harvard University-Smithsonian Institution

Subjects
Physics, [PHYS]Physics [physics], Molecular cloud, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, 010402 general chemistry, 01 natural sciences, 0104 chemical sciences, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, Abundance (ecology), 0103 physical sciences, Radiative transfer, Protostar, Spectral resolution, Low Mass, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), ComputingMilieux_MISCELLANEOUS, Line (formation), Envelope (waves)
Abstract

According to traditional gas-phase chemical models, O2 should be abundant in molecular clouds, but until recently, attempts to detect interstellar O2 line emission with ground- and space-based observatories have failed. Following the multi-line detections of O2 with low abundances in the Orion and rho Oph A molecular clouds with Herschel, it is important to investigate other environments, and we here quantify the O2 abundance near a solar-mass protostar. Observations of O2, at 487 GHz toward a deeply embedded low-mass Class 0 protostar, NGC 1333-IRAS 4A, are presented, using the HIFI instrument on the Herschel Space Observatory. Complementary data of the chemically related NO and CO molecules are obtained as well. The high spectral resolution data are analysed using radiative transfer models to infer column densities and abundances, and are tested directly against full gas-grain chemical models. The deep HIFI spectrum fails to show O2 at the velocity of the dense protostellar envelope, implying one of the lowest abundance upper limits of O2/H2 at, 15 pages, 13 figures, accepted by Astronomy & Astrophysics

Published
2013

6. An Analysis of the Environments of FU Orionis Objects with Herschel

Author

Ágnes Kóspál, Sascha P. Quanz, Jo-Hsin Chen, Thomas Henning, Stephen L. Skinner, Manuel Guedel, Joel D. Green, Jeong-Eun Lee, Jeroen Bouwman, Manuel Merello, Tim A. van Kempen, Michael M. Dunham, Gregory J. Herczeg, Gwendolyn Meeus, A. Liebhart, Neal J. Evans, and UAM. Departamento de Física Teórica

Subjects
010504 meteorology & atmospheric sciences, FOS: Physical sciences, individual (HBC 722, FU Orionis, V1057 Cyg, V1735 Cyg, V1331 Cyg, V1515 Cyg) [Stars], Astrophysics, 01 natural sciences, Stars: individual (HBC 722, FU Orionis, V1057 Cyg, V1735 Cyg, V1331 Cyg, V1515 Cyg), pre-main sequence [Stars], 0103 physical sciences, Protostar, ISM [submillimeter], Spectroscopy, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), 0105 earth and related environmental sciences, Physics, jets and outflows [ISM], Física, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, T Tauri star, Caltech Submillimeter Observatory, ISM: jets and outflows, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Stars: variables: T Tauri, Herbig Ae/Be, Stars: pre-main sequence, submillimeter: ISM, variables: T Tauri, Herbig Ae/Be [Stars]
Abstract

The Astrophysical Journal 772.1 (2013): 117, reproduced by permission of the AAS, We present Herschel-HIFI, SPIRE, and PACS 50-670 μm imaging and spectroscopy of six FU Orionis-type objects and candidates (FU Orionis, V1735 Cyg, V1515 Cyg, V1057 Cyg, V1331 Cyg, and HBC 722), ranging in outburst date from 1936 to 2010, from the "FOOSH" (FU Orionis Objects Surveyed with Herschel) program, as well as ancillary results from Spitzer Infrared Spectrograph and the Caltech Submillimeter Observatory. In their system properties (L bol, T bol, and line emission), we find that FUors are in a variety of evolutionary states. Additionally, some FUors have features of both Class I and II sources: warm continuum consistent with Class II sources, but rotational line emission typical of Class I, far higher than Class II sources of similar mass/luminosity. Combining several classification techniques, we find an evolutionary sequence consistent with previous mid-IR indicators. We detect [O I] in every source at luminosities consistent with Class 0/I protostars, much greater than in Class II disks. We detect transitions of 13CO (J up of 5-8) around two sources (V1735 Cyg and HBC 722) but attribute them to nearby protostars. Of the remaining sources, three (FU Ori, V1515 Cyg, and V1331 Cyg) exhibit only low-lying CO, but one (V1057 Cyg) shows CO up to J = 23 → 22 and evidence for H2O and OH emission, at strengths typical of protostars rather than T Tauri stars. Rotational temperatures for "cool" CO components range from 20 to 81 K, for ∼ 1050 total CO molecules. We detect [C I] and [N II] primarily as diffuse emission, The research of J.-E. L. is supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science, and Technology (No. 2012-044689).

Published
2013

7. Multi-line detection of O_2 toward ρ Ophiuchi A

Author

Laurent Pagani, G. Olofsson, Charlotte Vastel, Gary J. Melnick, Paola Caselli, Paul F. Goldsmith, Emmanuel Caux, S. Bruderer, R. L. Snell, A. O. H. Olofsson, Åke Hjalmarson, E. Roueff, D. J. Hollenbach, J. R. Goicoechea, Pierre Encrenaz, Aa. Sandqvist, Per Bjerkeli, S. Viti, T. A. Bell, J. Le Bourlot, Per Bergman, Bengt Larsson, E. Falgarone, F. F. S. van der Tak, René Liseau, John H. Black, Di Li, Kay Justtanont, F. Le Petit, E. F. van Dishoeck, D. C. Lis, M. De Luca, Z. Nagy, Arnold O. Benz, Michael J. Kaufman, Jo-Hsin Chen, E. A. Bergin, Maryvonne Gerin, Umut A. Yildiz, foreign laboratories (FL), CERN [Genève], 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), Onsala Space Observatory (OSO), Chalmers University of Technology [Göteborg], 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), Department of Astronomy [Ann Arbor], University of Michigan [Ann Arbor], University of Michigan System-University of Michigan System, Indiana University Cyclotron Facility (IUCF), Indiana University [Bloomington], Indiana University System-Indiana University System, Max-Planck-Institut für Extraterrestrische Physik (MPE), 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, National Taiwan University, Onsala Space Observatory, Iowa State University (ISU), SRON Netherlands Institute for Space Research (SRON), Stockholm University, Leiden Observatory [Leiden], Universiteit Leiden [Leiden], Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-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), Astronomy, École normale supérieure - Paris (ENS-PSL), 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), 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), and Universiteit Leiden

Subjects
Aperture, DARK-CLOUD, Astrophysics, MAIN CLOUD, PHOTODISSOCIATION REGIONS, 010402 general chemistry, OPH CLOUD, 7. Clean energy, 01 natural sciences, ISM: clouds, Spectral line, ISM: abundances, law.invention, Telescope, Far infrared, law, 0103 physical sciences, 010303 astronomy & astrophysics, ISM: individual objects: rho Oph A SM1, ComputingMilieux_MISCELLANEOUS, Line (formation), Physics, [PHYS]Physics [physics], DUST GRAINS, stars: formation, Molecular cloud, Astronomy and Astrophysics, ISM: molecules, 0104 chemical sciences, ISM: lines and bands, INTERSTELLAR HYDROGEN-PEROXIDE, C-I EMISSION, Interstellar medium, ODIN SATELLITE, SUBMILLIMETER OBSERVATIONS, 13. Climate action, Space and Planetary Science, MOLECULAR CLOUDS, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Water vapor
Abstract

Context. Models of pure gas-phase chemistry in well-shielded regions of molecular clouds predict relatively high levels of molecular oxygen, O-2, and water, H2O. These high abundances imply high cooling rates, leading to relatively short timescales for the evolution of gravitationally unstable dense cores, forming stars and planets. Contrary to expectations, the dedicated space missions SWAS and Odin typically found only very small amounts of water vapour and essentially no O-2 in the dense star-forming interstellar medium.Aims. Only toward rho OphA did Odin detect a very weak line of O-2 at 119 GHz in a beam of size 10 arcmin. The line emission of related molecules changes on angular scales of the order of some tens of arcseconds, requiring a larger telescope aperture such as that of the Herschel Space Observatory to resolve the O-2 emission and pinpoint its origin.Methods. We use the Heterodyne Instrument for the Far Infrared (HIFI) aboard Herschel to obtain high resolution O-2 spectra toward selected positions in the rho Oph A core. These data are analysed using standard techniques for O2 excitation and compared to recent PDR-like chemical cloud models.Results. The N-J = 3(3)-1(2) line at 487.2 GHz is clearly detected toward all three observed positions in the rho Oph A core. In addition, an oversampled map of the 5(4)-3(4) transition at 773.8 GHz reveals the detection of the line in only half of the observed area. On the basis of their ratios, the temperature of the O-2 emitting gas appears to vary quite substantially, with warm gas (greater than or similar to 50 K) being adjacent to a much colder region, of temperatures lower than 30 K.Conclusions. The exploited models predict that the O-2 column densities are sensitive to the prevailing dust temperatures, but rather insensitive to the temperatures of the gas. In agreement with these models, the observationally determined O-2 column densities do not seem to depend strongly on the derived gas temperatures, but fall into the range N(O-2) = 3 to greater than or similar to 6 x 10(15) cm(-2). Beam-averaged O-2 abundances are about 5 x 10(-8) relative to H-2. Combining the HIFI data with earlier Odin observations yields a source size at 119 GHz in the range of 4 to 5 arcmin, encompassing the entire rho Oph A core. We speculate that one of the reasons for the generally very low detection rate of O-2 is the short period of time during which O-2 molecules are reasonably abundant in molecular clouds.

Published
2012

8. Herschel Measurements of Molecular Oxygen in Orion

Author

Paul F. Goldsmith, René Liseau, Tom A. Bell, John H. Black, Jo-Hsin Chen, David Hollenbach, Michael J. Kaufman, Di Li, Dariusz C. Lis, Gary Melnick, David Neufeld, Laurent Pagani, Ronald Snell, Arnold O. Benz, Edwin Bergin, Simon Bruderer, Paola Caselli, Emmanuel Caux, Pierre Encrenaz, Edith Falgarone, Maryvonne Gerin, Javier R. Goicoechea, Åke Hjalmarson, Bengt Larsson, Jacques Le Bourlot, Franck Le Petit, Massimo De Luca, Zsofia Nagy, Evelyne Roueff, Aage Sandqvist, Floris van der Tak, Ewine F. van Dishoeck, Charlotte Vastel, Serena Viti, Umut Yıldız, Astronomy, Department of Radio and Space Science [Göteborg], Chalmers University of Technology [Göteborg], 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), Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University [Cambridge]-Smithsonian Institution, INAF - Osservatorio Astrofisico di Arcetri (OAA), Istituto Nazionale di Astrofisica (INAF), Centre d'étude spatiale des rayonnements (CESR), 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), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Onsala Space Observatory (OSO), SRON Netherlands Institute for Space Research (SRON), Max-Planck-Institut für Radioastronomie (MPIFR), 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), Harvard University-Smithsonian Institution, 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 sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS Paris), Smithsonian Institution-Harvard University [Cambridge], 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, and 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)

Subjects
ROTATIONAL-EXCITATION, WAVE-ASTRONOMY-SATELLITE, DISSOCIATIVE RECOMBINATION, Mean kinetic temperature, Abundance (chemistry), FOS: Physical sciences, Astrophysics, 7. Clean energy, 01 natural sciences, ISM: abundances, ISM: individual objects (Orion), O-2 ABUNDANCE, UPPER LIMITS, 0103 physical sciences, 010303 astronomy & astrophysics, Line (formation), ISM: individual objects: Orion, Physics, DENSE INTERSTELLAR CLOUDS, GAS-PHASE CHEMISTRY, 010308 nuclear & particles physics, Filling factor, astrochemistry, Astronomy and Astrophysics, Elemental oxygen, INTER-STELLAR CLOUDS, APERTURE SYNTHESIS, Astrophysics - Astrophysics of Galaxies, ISM: molecules, [PHYS.ASTR.GA]Physics [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA], 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Excited state, submillimeter: ISM, [SDU.ASTR.GA]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA], Molecular oxygen, INELASTIC-COLLISIONS, Beam (structure)
Abstract

International audience; We report observations of three rotational transitions of molecular oxygen (O2) in emission from the H2 Peak 1 position of vibrationally excited molecular hydrogen in Orion. We observed the 487 GHz, 774 GHz, and 1121 GHz lines using the Heterodyne Instrument for the Far Infrared on the Herschel Space Observatory, having velocities of 11 km s-1 to 12 km s-1 and widths of 3 km s-1. The beam-averaged column density is N(O2) = 6.5 × 1016 cm-2, and assuming that the source has an equal beam-filling factor for all transitions (beam widths 44, 28, and 19''), the relative line intensities imply a kinetic temperature between 65 K and 120 K. The fractional abundance of O2 relative to H2 is (0.3-7.3) × 10-6. The unusual velocity suggests an association with a ~5'' diameter source, denoted Peak A, the Western Clump, or MF4. The mass of this source is ~10 M sun and the dust temperature is >=150 K. Our preferred explanation of the enhanced O2 abundance is that dust grains in this region are sufficiently warm (T >= 100 K) to desorb water ice and thus keep a significant fraction of elemental oxygen in the gas phase, with a significant fraction as O2. For this small source, the line ratios require a temperature >=180 K. The inferred O2 column density sime5 × 1018 cm-2 can be produced in Peak A, having N(H2) ~= 4 × 1024 cm-2. An alternative mechanism is a low-velocity (10-15 km s-1) C-shock, which can produce N(O2) up to 1017 cm-2. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

Published
2011

9. Deep observations of O2 toward a low-mass protostar with Herschel-HIFI.

Author

Yıldız, Umut A., Acharyya, Kinsuk, Goldsmith, Paul F., Van Dishoeck, Ewine F., Melnick, Gary, Snell, Ronald, Liseau, René, Jo-Hsin Chen, Pagani, Laurent, Bergin, Edwin, Caselli, Paola, Herbst, Eric, Kristensen, Lars E., Visser, Ruud, Lis, Dariusz C., and Gerin, Maryvonne

Subjects
ASTRONOMICAL observations, OXYGEN, LOW mass stars, PROTOSTARS, GAS phase reactions, COSMIC abundances, MOLECULAR clouds
Abstract

Context. According to traditional gas-phase chemical models, O2 should be abundant in molecular clouds, but until recently, attempts to detect interstellar O2 line emission with ground- and space-based observatories have failed. Aims. Following the multi-line detections of O2 with low abundances in the Orion and ? Oph A molecular clouds with Herschel, it is important to investigate other environments, and we here quantify the O2 abundance near a solar-mass protostar. Methods. Observations of molecular oxygen, O2, at 487 GHz toward a deeply embedded low-mass Class 0 protostar, NGC 1333- IRAS 4A, are presented, using the Heterodyne Instrument for the Far Infrared (HIFI) on the Herschel Space Observatory. Complementary data of the chemically related NO and CO molecules are obtained as well. The high spectral resolution data are analysed using radiative transfer models to infer column densities and abundances, and are tested directly against full gas-grain chemical models. Results. The deep HIFI spectrum fails to show O2 at the velocity of the dense protostellar envelope, implying one of the lowest abundance upper limits of O2/H2 at ⩽6× 10-9 (3σ). The O2/CO abundance ratio is less than 0.005. However, a tentative (4.5σ) detection of O2 is seen at the velocity of the surrounding NGC 1333 molecular cloud, shifted by 1 km s-1 relative to the protostar. For the protostellar envelope, pure gas-phase models and gas-grain chemical models require a long pre-collapse phase (∼0.7-1 × 106 years), during which atomic and molecular oxygen are frozen out onto dust grains and fully converted to H2O, to avoid overproduction of O2 in the dense envelope. The same model also reproduces the limits on the chemically related NO molecule if hydrogenation of NO on the grains to more complex molecules such as NH2OH, found in recent laboratory experiments, is included. The tentative detection of O2 in the surrounding cloud is consistent with a low-density PDR model with small changes in reaction rates. Conclusions. The low O2 abundance in the collapsing envelope around a low-mass protostar suggests that the gas and ice entering protoplanetary disks is very poor in O2. [ABSTRACT FROM AUTHOR]

Published
2013
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10. AN ANALYSIS OF THE ENVIRONMENTS OF FU ORIONIS OBJECTS WITH HERSCHEL.

Author

GREEN, JOEL D., EVANS II, NEAL J., KÓSPÁL, ÁGNES, HERCZEG, GREGORY, QUANZ, SASCHA P., HENNING, THOMAS, VAN KEMPEN, TIM A., JEONG-EUN LEE, DUNHAM, MICHAEL M., MEEUS, GWENDOLYN, BOUWMAN, JEROEN, JO-HSIN CHEN, GÜDEL, MANUEL, SKINNER, STEPHEN L., LIEBHART, ARMIN, and MERELLO, MANUEL

Subjects
METEOR showers, PROTOSTARS, T Tauri stars, BIPOLAR outflows (Astrophysics), VARIABLE stars, HERBIG Ae/Be stars
Abstract

We present Herschel-HIFI, SPIRE, and PACS 50-670 μm imaging and spectroscopy of six FU Orionis-type objects and candidates (FU Orionis, V1735 Cyg, V1515 Cyg, V1057 Cyg, V1331 Cyg, and HBC 722), ranging in outburst date from 1936 to 2010, from the "FOOSH" (FU Orionis Objects Surveyed with Herschel) program, as well as ancillary results from Spitzer Infrared Spectrograph and the Caltech Submillimeter Observatory. In their system properties (Lbol, Tbol, and line emission), we find that FUors are in a variety of evolutionary states. Additionally, some FUors have features of both Class I and II sources: warm continuum consistent with Class II sources, but rotational line emission typical of Class I, far higher than Class II sources of similar mass/luminosity. Combining several classification techniques, we find an evolutionary sequence consistent with previous mid-IR indicators. We detect [O I] in every source at luminosities consistent with Class 0/I protostars, much greater than in Class II disks. We detect transitions of 13CO (Jup of 5-8) around two sources (V1735 Cyg and HBC 722) but attribute them to nearby protostars. Of the remaining sources, three (FU Ori, V1515 Cyg, and V1331 Cyg) exhibit only low-lying CO, but one (V1057 Cyg) shows CO up to J = 23 → 22 and evidence for H2O and OH emission, at strengths typical of protostars rather than T Tauri stars. Rotational temperatures for "cool" CO components range from 20 to 81 K, for ~ 1050 total CO molecules. We detect [C I] and [N II] primarily as diffuse emission. [ABSTRACT FROM AUTHOR]

Published
2013
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