METAL-POOR LITHIUM-RICH GIANTS IN THE RADIAL VELOCITY EXPERIMENT SURVEY
Identifieur interne : 001649 ( PascalFrancis/Corpus ); précédent : 001648; suivant : 001650METAL-POOR LITHIUM-RICH GIANTS IN THE RADIAL VELOCITY EXPERIMENT SURVEY
Auteurs : Gregory R. Ruchti ; Jon P. Fulbright ; Rosemary F. G. Wyse ; Gerard F. Gilmore ; Eva K. Grebel ; Olivier Bienayme ; Joss Bland-Hawthorn ; Ken C. Freeman ; Brad K. Gibson ; Ulisse Munari ; Julio F. Navarro ; Quentin A. Parker ; Warren Reid ; George M. Seabroke ; Arnaud Siebert ; Alessandro Siviero ; Matthias Steinmetz ; Fred G. Watson ; Mary Williams ; Tomaz ZwitterSource :
- The Astrophysical journal [ 0004-637X ] ; 2011.
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Abstract
We report the discovery of eight lithium-rich field giants found in a high-resolution spectroscopic sample of over 700 metal-poor stars ([Fe/H] < -0.5) selected from the Radial Velocity Experiment survey. The majority of the Li-rich giants in our sample are very metal-poor ([Fe/H] ? -1.9), and have a Li abundance (in the form of 7Li), A(Li) = log(n(Li)/n(H)) + 12, between 2.30 and 3.63, well above the typical upper red giant branch (RGB) limit, A(Li) < 0.5, while two stars, with A(Li) ˜ 1.7-1.8, show similar lithium abundances to normal giants at the same gravity. We further included two metal-poor, Li-rich globular cluster giants in our sample, namely the previously discovered M3-IV101 and newly discovered (in this work) M68-A96. This comprises the largest sample of metal-poor Li-rich giants to date. We performed a detailed abundance analysis of all stars, finding that the majority of our sample stars have elemental abundances similar to that of Li-normal halo giants. Although the evolutionary phase of each Li-rich giant cannot be definitively determined, the Li-rich phase is likely connected to extra mixing at the RGB bump or early asymptotic giant branch that triggers cool bottom processing in which the bottom of the outer convective envelope is connected to the H-burning shell in the star. The surface of a star becomes Li-enhanced as 7Be (which burns to 7Li) is transported to the stellar surface via the Cameron-Fowler mechanism. We discuss and discriminate among several models for the extra mixing that can cause Li production, given the detailed abundances of the Li-rich giants in our sample.
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Format Inist (serveur)
| NO : | PASCAL 12-0058031 INIST |
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| ET : | METAL-POOR LITHIUM-RICH GIANTS IN THE RADIAL VELOCITY EXPERIMENT SURVEY |
| AU : | RUCHTI (Gregory R.); FULBRIGHT (Jon P.); WYSE (Rosemary F. G.); GILMORE (Gerard F.); GREBEL (Eva K.); BIENAYME (Olivier); BLAND-HAWTHORN (Joss); FREEMAN (Ken C.); GIBSON (Brad K.); MUNARI (Ulisse); NAVARRO (Julio F.); PARKER (Quentin A.); REID (Warren); SEABROKE (George M.); SIEBERT (Arnaud); SIVIERO (Alessandro); STEINMETZ (Matthias); WATSON (Fred G.); WILLIAMS (Mary); ZWITTER (Tomaz) |
| AF : | Bloomberg Center for Physics & Astronomy, Johns Hopkins University, 3400 North Charles Street/Baltimore, MD 21218/Etats-Unis (1 aut., 2 aut., 3 aut.); Institute of Astronomy, University of Cambridge, Madingley Road/Cambridge CB3 0HA/Royaume-Uni (4 aut.); Astronomy Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203/Jeddah 21589/Arabie Saoudite (4 aut.); Astronomisches Rechen-Institut, Zentrum für Astronomie der Universitat Heidelberg, Mönchhofstr. 12-14/69120 Heidelberg/Allemagne (5 aut.); Observatoire de Strasbourg, 11 Rue de l'Université/67000 Strasbourg/France (6 aut., 15 aut.); Sydney Institute for Astronomy, School of Physics A28, University of Sydney/NSW 2006/Australie (7 aut.); RSAA Australian National University, Mount Stromlo Observatory, Cotter Road, Weston Creek/Canberra, ACT 2611/Australie (8 aut.); Jeremiah Horrocks Institute for Astrophysics & Super-computing, University of Central Lancashire/Preston PR1 2HE/Royaume-Uni (9 aut.); Department of Astronomy & Physics, Saint Marys University/Halifax B3H 3C3/Canada (9 aut.); INAF Osservatorio Astronomico di Padova, Via dell'Osservatorio 8/36012 Asiago/Italie (10 aut.); Department of Physics and Astronomy, University of Victoria, P.O. Box 3055, Station CSC/Victoria, BC V8W 3P6/Canada (11 aut.); Australian Astronomical Observatory/Coonabarabran, NSW 2357/Australie (12 aut., 18 aut.); Department of Physics and Astronomy, Macquarie University/Sydney, NSW 2109/Australie (12 aut., 13 aut.); Macquarie Research Centre for Astronomy, Astrophysics & Astrophotonics, Macquarie University/Sydney, NSW 2109/Australie (12 aut.); Mullard Space Science Laboratory, University College London, Holmbury St. Mary/Dorking RH5 6NT/Royaume-Uni (14 aut.); Department of Astronomy, Padova University, Vicolo dell'Osservatorio 2/35122 Padova/Italie (16 aut.); Leibniz-Institut für Astrophysik Potsdam (AIP), An der Sternwarte 16/14482 Potsdam/Allemagne (16 aut., 17 aut., 19 aut.); Faculty of Mathematics and Physics, University of Ljubljana, Jadranska 19/1000 Ljubljana/Slovénie (20 aut.); Center of Excellence SPACE-SI, Askerceva cesta 12/1000 Ljubljana/Slovénie (20 aut.) |
| DT : | Publication en série; Niveau analytique |
| SO : | The Astrophysical journal; ISSN 0004-637X; Coden ASJOAB; Royaume-Uni; Da. 2011; Vol. 743; No. 2 p. 1; 107.1-107.14; Bibl. 3/4 p. |
| LA : | Anglais |
| EA : | We report the discovery of eight lithium-rich field giants found in a high-resolution spectroscopic sample of over 700 metal-poor stars ([Fe/H] < -0.5) selected from the Radial Velocity Experiment survey. The majority of the Li-rich giants in our sample are very metal-poor ([Fe/H] ? -1.9), and have a Li abundance (in the form of 7Li), A(Li) = log(n(Li)/n(H)) + 12, between 2.30 and 3.63, well above the typical upper red giant branch (RGB) limit, A(Li) < 0.5, while two stars, with A(Li) ˜ 1.7-1.8, show similar lithium abundances to normal giants at the same gravity. We further included two metal-poor, Li-rich globular cluster giants in our sample, namely the previously discovered M3-IV101 and newly discovered (in this work) M68-A96. This comprises the largest sample of metal-poor Li-rich giants to date. We performed a detailed abundance analysis of all stars, finding that the majority of our sample stars have elemental abundances similar to that of Li-normal halo giants. Although the evolutionary phase of each Li-rich giant cannot be definitively determined, the Li-rich phase is likely connected to extra mixing at the RGB bump or early asymptotic giant branch that triggers cool bottom processing in which the bottom of the outer convective envelope is connected to the H-burning shell in the star. The surface of a star becomes Li-enhanced as 7Be (which burns to 7Li) is transported to the stellar surface via the Cameron-Fowler mechanism. We discuss and discriminate among several models for the extra mixing that can cause Li production, given the detailed abundances of the Li-rich giants in our sample. |
| CC : | 001E03 |
| FD : | Vitesse radiale; Etoile pauvre en métal; Abondance stellaire; Géante rouge; Gravité; Amas globulaire; Abondance élément; Mélangeage; Branche géante asymptotique; Enveloppe convective; Etoile enveloppe; Modèle; Etoile type avancé; Population type II; Amas stellaire |
| ED : | Radial velocity; Metal-poor stars; Stellar abundance; Red giant stars; Gravity; Globular clusters; Element abundance; Mixing; Asymptotic giant branch; Convective shell; Shell stars; Models; Late type stars; Population II; Star clusters |
| SD : | Abundancia estelar; Rama gigante asintótica; Cubierta convectiva; Modelo; Población estelar II |
| LO : | INIST-512.354000506045870090 |
| ID : | 12-0058031 |
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Pascal:12-0058031Le document en format XML
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Freeman</name><affiliation><inist:fA14 i1="07"><s1>RSAA Australian National University, Mount Stromlo Observatory, Cotter Road, Weston Creek</s1><s2>Canberra, ACT 2611</s2><s3>AUS</s3><sZ>8 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Gibson, Brad K" sort="Gibson, Brad K" uniqKey="Gibson B" first="Brad K." last="Gibson">Brad K. Gibson</name><affiliation><inist:fA14 i1="08"><s1>Jeremiah Horrocks Institute for Astrophysics & Super-computing, University of Central Lancashire</s1><s2>Preston PR1 2HE</s2><s3>GBR</s3><sZ>9 aut.</sZ></inist:fA14></affiliation><affiliation><inist:fA14 i1="09"><s1>Department of Astronomy & Physics, Saint Marys University</s1><s2>Halifax B3H 3C3</s2><s3>CAN</s3><sZ>9 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Munari, Ulisse" sort="Munari, Ulisse" uniqKey="Munari U" first="Ulisse" last="Munari">Ulisse Munari</name><affiliation><inist:fA14 i1="10"><s1>INAF Osservatorio Astronomico di Padova, Via dell'Osservatorio 8</s1><s2>36012 Asiago</s2><s3>ITA</s3><sZ>10 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Navarro, Julio F" sort="Navarro, Julio F" uniqKey="Navarro J" first="Julio F." last="Navarro">Julio F. Navarro</name><affiliation><inist:fA14 i1="11"><s1>Department of Physics and Astronomy, University of Victoria, P.O. Box 3055, Station CSC</s1><s2>Victoria, BC V8W 3P6</s2><s3>CAN</s3><sZ>11 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Parker, Quentin A" sort="Parker, Quentin A" uniqKey="Parker Q" first="Quentin A." last="Parker">Quentin A. Parker</name><affiliation><inist:fA14 i1="12"><s1>Australian Astronomical Observatory</s1><s2>Coonabarabran, NSW 2357</s2><s3>AUS</s3><sZ>12 aut.</sZ><sZ>18 aut.</sZ></inist:fA14></affiliation><affiliation><inist:fA14 i1="13"><s1>Department of Physics and Astronomy, Macquarie University</s1><s2>Sydney, NSW 2109</s2><s3>AUS</s3><sZ>12 aut.</sZ><sZ>13 aut.</sZ></inist:fA14></affiliation><affiliation><inist:fA14 i1="14"><s1>Macquarie Research Centre for Astronomy, Astrophysics & Astrophotonics, Macquarie University</s1><s2>Sydney, NSW 2109</s2><s3>AUS</s3><sZ>12 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Reid, Warren" sort="Reid, Warren" uniqKey="Reid W" first="Warren" last="Reid">Warren Reid</name><affiliation><inist:fA14 i1="13"><s1>Department of Physics and Astronomy, Macquarie University</s1><s2>Sydney, NSW 2109</s2><s3>AUS</s3><sZ>12 aut.</sZ><sZ>13 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Seabroke, George M" sort="Seabroke, George M" uniqKey="Seabroke G" first="George M." last="Seabroke">George M. Seabroke</name><affiliation><inist:fA14 i1="15"><s1>Mullard Space Science Laboratory, University College London, Holmbury St. Mary</s1><s2>Dorking RH5 6NT</s2><s3>GBR</s3><sZ>14 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Siebert, Arnaud" sort="Siebert, Arnaud" uniqKey="Siebert A" first="Arnaud" last="Siebert">Arnaud Siebert</name><affiliation><inist:fA14 i1="05"><s1>Observatoire de Strasbourg, 11 Rue de l'Université</s1><s2>67000 Strasbourg</s2><s3>FRA</s3><sZ>6 aut.</sZ><sZ>15 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Siviero, Alessandro" sort="Siviero, Alessandro" uniqKey="Siviero A" first="Alessandro" last="Siviero">Alessandro Siviero</name><affiliation><inist:fA14 i1="16"><s1>Department of Astronomy, Padova University, Vicolo dell'Osservatorio 2</s1><s2>35122 Padova</s2><s3>ITA</s3><sZ>16 aut.</sZ></inist:fA14></affiliation><affiliation><inist:fA14 i1="17"><s1>Leibniz-Institut für Astrophysik Potsdam (AIP), An der Sternwarte 16</s1><s2>14482 Potsdam</s2><s3>DEU</s3><sZ>16 aut.</sZ><sZ>17 aut.</sZ><sZ>19 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Steinmetz, Matthias" sort="Steinmetz, Matthias" uniqKey="Steinmetz M" first="Matthias" last="Steinmetz">Matthias Steinmetz</name><affiliation><inist:fA14 i1="17"><s1>Leibniz-Institut für Astrophysik Potsdam (AIP), An der Sternwarte 16</s1><s2>14482 Potsdam</s2><s3>DEU</s3><sZ>16 aut.</sZ><sZ>17 aut.</sZ><sZ>19 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Watson, Fred G" sort="Watson, Fred G" uniqKey="Watson F" first="Fred G." last="Watson">Fred G. Watson</name><affiliation><inist:fA14 i1="12"><s1>Australian Astronomical Observatory</s1><s2>Coonabarabran, NSW 2357</s2><s3>AUS</s3><sZ>12 aut.</sZ><sZ>18 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Williams, Mary" sort="Williams, Mary" uniqKey="Williams M" first="Mary" last="Williams">Mary Williams</name><affiliation><inist:fA14 i1="17"><s1>Leibniz-Institut für Astrophysik Potsdam (AIP), An der Sternwarte 16</s1><s2>14482 Potsdam</s2><s3>DEU</s3><sZ>16 aut.</sZ><sZ>17 aut.</sZ><sZ>19 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Zwitter, Tomaz" sort="Zwitter, Tomaz" uniqKey="Zwitter T" first="Tomaz" last="Zwitter">Tomaz Zwitter</name><affiliation><inist:fA14 i1="18"><s1>Faculty of Mathematics and Physics, University of Ljubljana, Jadranska 19</s1><s2>1000 Ljubljana</s2><s3>SVN</s3><sZ>20 aut.</sZ></inist:fA14></affiliation><affiliation><inist:fA14 i1="19"><s1>Center of Excellence SPACE-SI, Askerceva cesta 12</s1><s2>1000 Ljubljana</s2><s3>SVN</s3><sZ>20 aut.</sZ></inist:fA14></affiliation></author></titleStmt><publicationStmt><idno type="wicri:source">INIST</idno><idno type="inist">12-0058031</idno><date when="2011">2011</date><idno type="stanalyst">PASCAL 12-0058031 INIST</idno><idno type="RBID">Pascal:12-0058031</idno><idno type="wicri:Area/PascalFrancis/Corpus">001649</idno></publicationStmt><sourceDesc><biblStruct><analytic><title xml:lang="en" level="a">METAL-POOR LITHIUM-RICH GIANTS IN THE RADIAL VELOCITY EXPERIMENT SURVEY</title><author><name sortKey="Ruchti, Gregory R" sort="Ruchti, Gregory R" uniqKey="Ruchti G" first="Gregory R." last="Ruchti">Gregory R. Ruchti</name><affiliation><inist:fA14 i1="01"><s1>Bloomberg Center for Physics & Astronomy, Johns Hopkins University, 3400 North Charles Street</s1><s2>Baltimore, MD 21218</s2><s3>USA</s3><sZ>1 aut.</sZ><sZ>2 aut.</sZ><sZ>3 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Fulbright, Jon P" sort="Fulbright, Jon P" uniqKey="Fulbright J" first="Jon P." last="Fulbright">Jon P. Fulbright</name><affiliation><inist:fA14 i1="01"><s1>Bloomberg Center for Physics & Astronomy, Johns Hopkins University, 3400 North Charles Street</s1><s2>Baltimore, MD 21218</s2><s3>USA</s3><sZ>1 aut.</sZ><sZ>2 aut.</sZ><sZ>3 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Wyse, Rosemary F G" sort="Wyse, Rosemary F G" uniqKey="Wyse R" first="Rosemary F. G." last="Wyse">Rosemary F. G. Wyse</name><affiliation><inist:fA14 i1="01"><s1>Bloomberg Center for Physics & Astronomy, Johns Hopkins University, 3400 North Charles Street</s1><s2>Baltimore, MD 21218</s2><s3>USA</s3><sZ>1 aut.</sZ><sZ>2 aut.</sZ><sZ>3 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Gilmore, Gerard F" sort="Gilmore, Gerard F" uniqKey="Gilmore G" first="Gerard F." last="Gilmore">Gerard F. Gilmore</name><affiliation><inist:fA14 i1="02"><s1>Institute of Astronomy, University of Cambridge, Madingley Road</s1><s2>Cambridge CB3 0HA</s2><s3>GBR</s3><sZ>4 aut.</sZ></inist:fA14></affiliation><affiliation><inist:fA14 i1="03"><s1>Astronomy Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203</s1><s2>Jeddah 21589</s2><s3>SAU</s3><sZ>4 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Grebel, Eva K" sort="Grebel, Eva K" uniqKey="Grebel E" first="Eva K." last="Grebel">Eva K. Grebel</name><affiliation><inist:fA14 i1="04"><s1>Astronomisches Rechen-Institut, Zentrum für Astronomie der Universitat Heidelberg, Mönchhofstr. 12-14</s1><s2>69120 Heidelberg</s2><s3>DEU</s3><sZ>5 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Bienayme, Olivier" sort="Bienayme, Olivier" uniqKey="Bienayme O" first="Olivier" last="Bienayme">Olivier Bienayme</name><affiliation><inist:fA14 i1="05"><s1>Observatoire de Strasbourg, 11 Rue de l'Université</s1><s2>67000 Strasbourg</s2><s3>FRA</s3><sZ>6 aut.</sZ><sZ>15 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Bland Hawthorn, Joss" sort="Bland Hawthorn, Joss" uniqKey="Bland Hawthorn J" first="Joss" last="Bland-Hawthorn">Joss Bland-Hawthorn</name><affiliation><inist:fA14 i1="06"><s1>Sydney Institute for Astronomy, School of Physics A28, University of Sydney</s1><s2>NSW 2006</s2><s3>AUS</s3><sZ>7 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Freeman, Ken C" sort="Freeman, Ken C" uniqKey="Freeman K" first="Ken C." last="Freeman">Ken C. Freeman</name><affiliation><inist:fA14 i1="07"><s1>RSAA Australian National University, Mount Stromlo Observatory, Cotter Road, Weston Creek</s1><s2>Canberra, ACT 2611</s2><s3>AUS</s3><sZ>8 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Gibson, Brad K" sort="Gibson, Brad K" uniqKey="Gibson B" first="Brad K." last="Gibson">Brad K. Gibson</name><affiliation><inist:fA14 i1="08"><s1>Jeremiah Horrocks Institute for Astrophysics & Super-computing, University of Central Lancashire</s1><s2>Preston PR1 2HE</s2><s3>GBR</s3><sZ>9 aut.</sZ></inist:fA14></affiliation><affiliation><inist:fA14 i1="09"><s1>Department of Astronomy & Physics, Saint Marys University</s1><s2>Halifax B3H 3C3</s2><s3>CAN</s3><sZ>9 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Munari, Ulisse" sort="Munari, Ulisse" uniqKey="Munari U" first="Ulisse" last="Munari">Ulisse Munari</name><affiliation><inist:fA14 i1="10"><s1>INAF Osservatorio Astronomico di Padova, Via dell'Osservatorio 8</s1><s2>36012 Asiago</s2><s3>ITA</s3><sZ>10 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Navarro, Julio F" sort="Navarro, Julio F" uniqKey="Navarro J" first="Julio F." last="Navarro">Julio F. Navarro</name><affiliation><inist:fA14 i1="11"><s1>Department of Physics and Astronomy, University of Victoria, P.O. Box 3055, Station CSC</s1><s2>Victoria, BC V8W 3P6</s2><s3>CAN</s3><sZ>11 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Parker, Quentin A" sort="Parker, Quentin A" uniqKey="Parker Q" first="Quentin A." last="Parker">Quentin A. Parker</name><affiliation><inist:fA14 i1="12"><s1>Australian Astronomical Observatory</s1><s2>Coonabarabran, NSW 2357</s2><s3>AUS</s3><sZ>12 aut.</sZ><sZ>18 aut.</sZ></inist:fA14></affiliation><affiliation><inist:fA14 i1="13"><s1>Department of Physics and Astronomy, Macquarie University</s1><s2>Sydney, NSW 2109</s2><s3>AUS</s3><sZ>12 aut.</sZ><sZ>13 aut.</sZ></inist:fA14></affiliation><affiliation><inist:fA14 i1="14"><s1>Macquarie Research Centre for Astronomy, Astrophysics & Astrophotonics, Macquarie University</s1><s2>Sydney, NSW 2109</s2><s3>AUS</s3><sZ>12 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Reid, Warren" sort="Reid, Warren" uniqKey="Reid W" first="Warren" last="Reid">Warren Reid</name><affiliation><inist:fA14 i1="13"><s1>Department of Physics and Astronomy, Macquarie University</s1><s2>Sydney, NSW 2109</s2><s3>AUS</s3><sZ>12 aut.</sZ><sZ>13 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Seabroke, George M" sort="Seabroke, George M" uniqKey="Seabroke G" first="George M." last="Seabroke">George M. Seabroke</name><affiliation><inist:fA14 i1="15"><s1>Mullard Space Science Laboratory, University College London, Holmbury St. Mary</s1><s2>Dorking RH5 6NT</s2><s3>GBR</s3><sZ>14 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Siebert, Arnaud" sort="Siebert, Arnaud" uniqKey="Siebert A" first="Arnaud" last="Siebert">Arnaud Siebert</name><affiliation><inist:fA14 i1="05"><s1>Observatoire de Strasbourg, 11 Rue de l'Université</s1><s2>67000 Strasbourg</s2><s3>FRA</s3><sZ>6 aut.</sZ><sZ>15 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Siviero, Alessandro" sort="Siviero, Alessandro" uniqKey="Siviero A" first="Alessandro" last="Siviero">Alessandro Siviero</name><affiliation><inist:fA14 i1="16"><s1>Department of Astronomy, Padova University, Vicolo dell'Osservatorio 2</s1><s2>35122 Padova</s2><s3>ITA</s3><sZ>16 aut.</sZ></inist:fA14></affiliation><affiliation><inist:fA14 i1="17"><s1>Leibniz-Institut für Astrophysik Potsdam (AIP), An der Sternwarte 16</s1><s2>14482 Potsdam</s2><s3>DEU</s3><sZ>16 aut.</sZ><sZ>17 aut.</sZ><sZ>19 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Steinmetz, Matthias" sort="Steinmetz, Matthias" uniqKey="Steinmetz M" first="Matthias" last="Steinmetz">Matthias Steinmetz</name><affiliation><inist:fA14 i1="17"><s1>Leibniz-Institut für Astrophysik Potsdam (AIP), An der Sternwarte 16</s1><s2>14482 Potsdam</s2><s3>DEU</s3><sZ>16 aut.</sZ><sZ>17 aut.</sZ><sZ>19 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Watson, Fred G" sort="Watson, Fred G" uniqKey="Watson F" first="Fred G." last="Watson">Fred G. Watson</name><affiliation><inist:fA14 i1="12"><s1>Australian Astronomical Observatory</s1><s2>Coonabarabran, NSW 2357</s2><s3>AUS</s3><sZ>12 aut.</sZ><sZ>18 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Williams, Mary" sort="Williams, Mary" uniqKey="Williams M" first="Mary" last="Williams">Mary Williams</name><affiliation><inist:fA14 i1="17"><s1>Leibniz-Institut für Astrophysik Potsdam (AIP), An der Sternwarte 16</s1><s2>14482 Potsdam</s2><s3>DEU</s3><sZ>16 aut.</sZ><sZ>17 aut.</sZ><sZ>19 aut.</sZ></inist:fA14></affiliation></author><author><name sortKey="Zwitter, Tomaz" sort="Zwitter, Tomaz" uniqKey="Zwitter T" first="Tomaz" last="Zwitter">Tomaz Zwitter</name><affiliation><inist:fA14 i1="18"><s1>Faculty of Mathematics and Physics, University of Ljubljana, Jadranska 19</s1><s2>1000 Ljubljana</s2><s3>SVN</s3><sZ>20 aut.</sZ></inist:fA14></affiliation><affiliation><inist:fA14 i1="19"><s1>Center of Excellence SPACE-SI, Askerceva cesta 12</s1><s2>1000 Ljubljana</s2><s3>SVN</s3><sZ>20 aut.</sZ></inist:fA14></affiliation></author></analytic><series><title level="j" type="main">The Astrophysical journal</title><title level="j" type="abbreviated">Astrophys. j.</title><idno type="ISSN">0004-637X</idno><imprint><date when="2011">2011</date></imprint></series></biblStruct></sourceDesc><seriesStmt><title level="j" type="main">The Astrophysical journal</title><title level="j" type="abbreviated">Astrophys. j.</title><idno type="ISSN">0004-637X</idno></seriesStmt></fileDesc><profileDesc><textClass><keywords scheme="KwdEn" xml:lang="en"><term>Asymptotic giant branch</term><term>Convective shell</term><term>Element abundance</term><term>Globular clusters</term><term>Gravity</term><term>Late type stars</term><term>Metal-poor stars</term><term>Mixing</term><term>Models</term><term>Population II</term><term>Radial velocity</term><term>Red giant stars</term><term>Shell stars</term><term>Star clusters</term><term>Stellar abundance</term></keywords><keywords scheme="Pascal" xml:lang="fr"><term>Vitesse radiale</term><term>Etoile pauvre en métal</term><term>Abondance stellaire</term><term>Géante rouge</term><term>Gravité</term><term>Amas globulaire</term><term>Abondance élément</term><term>Mélangeage</term><term>Branche géante asymptotique</term><term>Enveloppe convective</term><term>Etoile enveloppe</term><term>Modèle</term><term>Etoile type avancé</term><term>Population type II</term><term>Amas stellaire</term></keywords></textClass></profileDesc></teiHeader><front><div type="abstract" xml:lang="en">We report the discovery of eight lithium-rich field giants found in a high-resolution spectroscopic sample of over 700 metal-poor stars ([Fe/H] < -0.5) selected from the Radial Velocity Experiment survey. The majority of the Li-rich giants in our sample are very metal-poor ([Fe/H] ? -1.9), and have a Li abundance (in the form of 7Li), A(Li) = log(n(Li)/n(H)) + 12, between 2.30 and 3.63, well above the typical upper red giant branch (RGB) limit, A(Li) < 0.5, while two stars, with A(Li) ˜ 1.7-1.8, show similar lithium abundances to normal giants at the same gravity. We further included two metal-poor, Li-rich globular cluster giants in our sample, namely the previously discovered M3-IV101 and newly discovered (in this work) M68-A96. This comprises the largest sample of metal-poor Li-rich giants to date. We performed a detailed abundance analysis of all stars, finding that the majority of our sample stars have elemental abundances similar to that of Li-normal halo giants. Although the evolutionary phase of each Li-rich giant cannot be definitively determined, the Li-rich phase is likely connected to extra mixing at the RGB bump or early asymptotic giant branch that triggers cool bottom processing in which the bottom of the outer convective envelope is connected to the H-burning shell in the star. The surface of a star becomes Li-enhanced as 7Be (which burns to 7Li) is transported to the stellar surface via the Cameron-Fowler mechanism. We discuss and discriminate among several models for the extra mixing that can cause Li production, given the detailed abundances of the Li-rich giants in our sample.</div></front></TEI><inist><standard h6="B"><pA><fA01 i1="01" i2="1"><s0>0004-637X</s0></fA01><fA02 i1="01"><s0>ASJOAB</s0></fA02><fA03 i2="1"><s0>Astrophys. j.</s0></fA03><fA05><s2>743</s2></fA05><fA06><s2>2</s2><s3>p. 1</s3></fA06><fA08 i1="01" i2="1" l="ENG"><s1>METAL-POOR LITHIUM-RICH GIANTS IN THE RADIAL VELOCITY EXPERIMENT SURVEY</s1></fA08><fA11 i1="01" i2="1"><s1>RUCHTI (Gregory R.)</s1></fA11><fA11 i1="02" i2="1"><s1>FULBRIGHT (Jon P.)</s1></fA11><fA11 i1="03" i2="1"><s1>WYSE (Rosemary F. G.)</s1></fA11><fA11 i1="04" i2="1"><s1>GILMORE (Gerard F.)</s1></fA11><fA11 i1="05" i2="1"><s1>GREBEL (Eva K.)</s1></fA11><fA11 i1="06" i2="1"><s1>BIENAYME (Olivier)</s1></fA11><fA11 i1="07" i2="1"><s1>BLAND-HAWTHORN (Joss)</s1></fA11><fA11 i1="08" i2="1"><s1>FREEMAN (Ken C.)</s1></fA11><fA11 i1="09" i2="1"><s1>GIBSON (Brad K.)</s1></fA11><fA11 i1="10" i2="1"><s1>MUNARI (Ulisse)</s1></fA11><fA11 i1="11" i2="1"><s1>NAVARRO (Julio F.)</s1></fA11><fA11 i1="12" i2="1"><s1>PARKER (Quentin A.)</s1></fA11><fA11 i1="13" i2="1"><s1>REID (Warren)</s1></fA11><fA11 i1="14" i2="1"><s1>SEABROKE (George M.)</s1></fA11><fA11 i1="15" i2="1"><s1>SIEBERT (Arnaud)</s1></fA11><fA11 i1="16" i2="1"><s1>SIVIERO (Alessandro)</s1></fA11><fA11 i1="17" i2="1"><s1>STEINMETZ (Matthias)</s1></fA11><fA11 i1="18" i2="1"><s1>WATSON (Fred G.)</s1></fA11><fA11 i1="19" i2="1"><s1>WILLIAMS (Mary)</s1></fA11><fA11 i1="20" i2="1"><s1>ZWITTER (Tomaz)</s1></fA11><fA14 i1="01"><s1>Bloomberg Center for Physics & Astronomy, Johns Hopkins University, 3400 North Charles Street</s1><s2>Baltimore, MD 21218</s2><s3>USA</s3><sZ>1 aut.</sZ><sZ>2 aut.</sZ><sZ>3 aut.</sZ></fA14><fA14 i1="02"><s1>Institute of Astronomy, University of Cambridge, Madingley Road</s1><s2>Cambridge CB3 0HA</s2><s3>GBR</s3><sZ>4 aut.</sZ></fA14><fA14 i1="03"><s1>Astronomy Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203</s1><s2>Jeddah 21589</s2><s3>SAU</s3><sZ>4 aut.</sZ></fA14><fA14 i1="04"><s1>Astronomisches Rechen-Institut, Zentrum für Astronomie der Universitat Heidelberg, Mönchhofstr. 12-14</s1><s2>69120 Heidelberg</s2><s3>DEU</s3><sZ>5 aut.</sZ></fA14><fA14 i1="05"><s1>Observatoire de Strasbourg, 11 Rue de l'Université</s1><s2>67000 Strasbourg</s2><s3>FRA</s3><sZ>6 aut.</sZ><sZ>15 aut.</sZ></fA14><fA14 i1="06"><s1>Sydney Institute for Astronomy, School of Physics A28, University of Sydney</s1><s2>NSW 2006</s2><s3>AUS</s3><sZ>7 aut.</sZ></fA14><fA14 i1="07"><s1>RSAA Australian National University, Mount Stromlo Observatory, Cotter Road, Weston Creek</s1><s2>Canberra, ACT 2611</s2><s3>AUS</s3><sZ>8 aut.</sZ></fA14><fA14 i1="08"><s1>Jeremiah Horrocks Institute for Astrophysics & Super-computing, University of Central Lancashire</s1><s2>Preston PR1 2HE</s2><s3>GBR</s3><sZ>9 aut.</sZ></fA14><fA14 i1="09"><s1>Department of Astronomy & Physics, Saint Marys University</s1><s2>Halifax B3H 3C3</s2><s3>CAN</s3><sZ>9 aut.</sZ></fA14><fA14 i1="10"><s1>INAF Osservatorio Astronomico di Padova, Via dell'Osservatorio 8</s1><s2>36012 Asiago</s2><s3>ITA</s3><sZ>10 aut.</sZ></fA14><fA14 i1="11"><s1>Department of Physics and Astronomy, University of Victoria, P.O. Box 3055, Station CSC</s1><s2>Victoria, BC V8W 3P6</s2><s3>CAN</s3><sZ>11 aut.</sZ></fA14><fA14 i1="12"><s1>Australian Astronomical Observatory</s1><s2>Coonabarabran, NSW 2357</s2><s3>AUS</s3><sZ>12 aut.</sZ><sZ>18 aut.</sZ></fA14><fA14 i1="13"><s1>Department of Physics and Astronomy, Macquarie University</s1><s2>Sydney, NSW 2109</s2><s3>AUS</s3><sZ>12 aut.</sZ><sZ>13 aut.</sZ></fA14><fA14 i1="14"><s1>Macquarie Research Centre for Astronomy, Astrophysics & Astrophotonics, Macquarie University</s1><s2>Sydney, NSW 2109</s2><s3>AUS</s3><sZ>12 aut.</sZ></fA14><fA14 i1="15"><s1>Mullard Space Science Laboratory, University College London, Holmbury St. Mary</s1><s2>Dorking RH5 6NT</s2><s3>GBR</s3><sZ>14 aut.</sZ></fA14><fA14 i1="16"><s1>Department of Astronomy, Padova University, Vicolo dell'Osservatorio 2</s1><s2>35122 Padova</s2><s3>ITA</s3><sZ>16 aut.</sZ></fA14><fA14 i1="17"><s1>Leibniz-Institut für Astrophysik Potsdam (AIP), An der Sternwarte 16</s1><s2>14482 Potsdam</s2><s3>DEU</s3><sZ>16 aut.</sZ><sZ>17 aut.</sZ><sZ>19 aut.</sZ></fA14><fA14 i1="18"><s1>Faculty of Mathematics and Physics, University of Ljubljana, Jadranska 19</s1><s2>1000 Ljubljana</s2><s3>SVN</s3><sZ>20 aut.</sZ></fA14><fA14 i1="19"><s1>Center of Excellence SPACE-SI, Askerceva cesta 12</s1><s2>1000 Ljubljana</s2><s3>SVN</s3><sZ>20 aut.</sZ></fA14><fA20><s2>107.1-107.14</s2></fA20><fA21><s1>2011</s1></fA21><fA23 i1="01"><s0>ENG</s0></fA23><fA43 i1="01"><s1>INIST</s1><s2>512</s2><s5>354000506045870090</s5></fA43><fA44><s0>0000</s0><s1>© 2012 INIST-CNRS. All rights reserved.</s1></fA44><fA45><s0>3/4 p.</s0></fA45><fA47 i1="01" i2="1"><s0>12-0058031</s0></fA47><fA60><s1>P</s1></fA60><fA61><s0>A</s0></fA61><fA64 i1="01" i2="1"><s0>The Astrophysical journal</s0></fA64><fA66 i1="01"><s0>GBR</s0></fA66><fC01 i1="01" l="ENG"><s0>We report the discovery of eight lithium-rich field giants found in a high-resolution spectroscopic sample of over 700 metal-poor stars ([Fe/H] < -0.5) selected from the Radial Velocity Experiment survey. The majority of the Li-rich giants in our sample are very metal-poor ([Fe/H] ? -1.9), and have a Li abundance (in the form of 7Li), A(Li) = log(n(Li)/n(H)) + 12, between 2.30 and 3.63, well above the typical upper red giant branch (RGB) limit, A(Li) < 0.5, while two stars, with A(Li) ˜ 1.7-1.8, show similar lithium abundances to normal giants at the same gravity. We further included two metal-poor, Li-rich globular cluster giants in our sample, namely the previously discovered M3-IV101 and newly discovered (in this work) M68-A96. This comprises the largest sample of metal-poor Li-rich giants to date. We performed a detailed abundance analysis of all stars, finding that the majority of our sample stars have elemental abundances similar to that of Li-normal halo giants. Although the evolutionary phase of each Li-rich giant cannot be definitively determined, the Li-rich phase is likely connected to extra mixing at the RGB bump or early asymptotic giant branch that triggers cool bottom processing in which the bottom of the outer convective envelope is connected to the H-burning shell in the star. The surface of a star becomes Li-enhanced as 7Be (which burns to 7Li) is transported to the stellar surface via the Cameron-Fowler mechanism. We discuss and discriminate among several models for the extra mixing that can cause Li production, given the detailed abundances of the Li-rich giants in our sample.</s0></fC01><fC02 i1="01" i2="3"><s0>001E03</s0></fC02><fC03 i1="01" i2="3" l="FRE"><s0>Vitesse radiale</s0><s5>26</s5></fC03><fC03 i1="01" i2="3" l="ENG"><s0>Radial velocity</s0><s5>26</s5></fC03><fC03 i1="02" i2="3" l="FRE"><s0>Etoile pauvre en métal</s0><s5>27</s5></fC03><fC03 i1="02" i2="3" l="ENG"><s0>Metal-poor stars</s0><s5>27</s5></fC03><fC03 i1="03" i2="X" l="FRE"><s0>Abondance stellaire</s0><s5>28</s5></fC03><fC03 i1="03" i2="X" l="ENG"><s0>Stellar abundance</s0><s5>28</s5></fC03><fC03 i1="03" i2="X" l="SPA"><s0>Abundancia estelar</s0><s5>28</s5></fC03><fC03 i1="04" i2="3" l="FRE"><s0>Géante rouge</s0><s5>29</s5></fC03><fC03 i1="04" i2="3" l="ENG"><s0>Red giant stars</s0><s5>29</s5></fC03><fC03 i1="05" i2="3" l="FRE"><s0>Gravité</s0><s5>30</s5></fC03><fC03 i1="05" i2="3" l="ENG"><s0>Gravity</s0><s5>30</s5></fC03><fC03 i1="06" i2="3" l="FRE"><s0>Amas globulaire</s0><s5>31</s5></fC03><fC03 i1="06" i2="3" l="ENG"><s0>Globular clusters</s0><s5>31</s5></fC03><fC03 i1="07" i2="3" l="FRE"><s0>Abondance élément</s0><s5>32</s5></fC03><fC03 i1="07" i2="3" l="ENG"><s0>Element abundance</s0><s5>32</s5></fC03><fC03 i1="08" i2="3" l="FRE"><s0>Mélangeage</s0><s5>33</s5></fC03><fC03 i1="08" i2="3" l="ENG"><s0>Mixing</s0><s5>33</s5></fC03><fC03 i1="09" i2="X" l="FRE"><s0>Branche géante asymptotique</s0><s5>34</s5></fC03><fC03 i1="09" i2="X" l="ENG"><s0>Asymptotic giant branch</s0><s5>34</s5></fC03><fC03 i1="09" i2="X" l="SPA"><s0>Rama gigante asintótica</s0><s5>34</s5></fC03><fC03 i1="10" i2="X" l="FRE"><s0>Enveloppe convective</s0><s5>35</s5></fC03><fC03 i1="10" i2="X" l="ENG"><s0>Convective shell</s0><s5>35</s5></fC03><fC03 i1="10" i2="X" l="SPA"><s0>Cubierta convectiva</s0><s5>35</s5></fC03><fC03 i1="11" i2="3" l="FRE"><s0>Etoile enveloppe</s0><s5>36</s5></fC03><fC03 i1="11" i2="3" l="ENG"><s0>Shell stars</s0><s5>36</s5></fC03><fC03 i1="12" i2="X" l="FRE"><s0>Modèle</s0><s5>37</s5></fC03><fC03 i1="12" i2="X" l="ENG"><s0>Models</s0><s5>37</s5></fC03><fC03 i1="12" i2="X" l="SPA"><s0>Modelo</s0><s5>37</s5></fC03><fC03 i1="13" i2="3" l="FRE"><s0>Etoile type avancé</s0><s5>38</s5></fC03><fC03 i1="13" i2="3" l="ENG"><s0>Late type stars</s0><s5>38</s5></fC03><fC03 i1="14" i2="X" l="FRE"><s0>Population type II</s0><s5>39</s5></fC03><fC03 i1="14" i2="X" l="ENG"><s0>Population II</s0><s5>39</s5></fC03><fC03 i1="14" i2="X" l="SPA"><s0>Población estelar II</s0><s5>39</s5></fC03><fC03 i1="15" i2="3" l="FRE"><s0>Amas stellaire</s0><s5>40</s5></fC03><fC03 i1="15" i2="3" l="ENG"><s0>Star clusters</s0><s5>40</s5></fC03><fN21><s1>037</s1></fN21><fN44 i1="01"><s1>OTO</s1></fN44><fN82><s1>OTO</s1></fN82></pA></standard><server><NO>PASCAL 12-0058031 INIST</NO><ET>METAL-POOR LITHIUM-RICH GIANTS IN THE RADIAL VELOCITY EXPERIMENT SURVEY</ET><AU>RUCHTI (Gregory R.); FULBRIGHT (Jon P.); WYSE (Rosemary F. G.); GILMORE (Gerard F.); GREBEL (Eva K.); BIENAYME (Olivier); BLAND-HAWTHORN (Joss); FREEMAN (Ken C.); GIBSON (Brad K.); MUNARI (Ulisse); NAVARRO (Julio F.); PARKER (Quentin A.); REID (Warren); SEABROKE (George M.); SIEBERT (Arnaud); SIVIERO (Alessandro); STEINMETZ (Matthias); WATSON (Fred G.); WILLIAMS (Mary); ZWITTER (Tomaz)</AU><AF>Bloomberg Center for Physics & Astronomy, Johns Hopkins University, 3400 North Charles Street/Baltimore, MD 21218/Etats-Unis (1 aut., 2 aut., 3 aut.); Institute of Astronomy, University of Cambridge, Madingley Road/Cambridge CB3 0HA/Royaume-Uni (4 aut.); Astronomy Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203/Jeddah 21589/Arabie Saoudite (4 aut.); Astronomisches Rechen-Institut, Zentrum für Astronomie der Universitat Heidelberg, Mönchhofstr. 12-14/69120 Heidelberg/Allemagne (5 aut.); Observatoire de Strasbourg, 11 Rue de l'Université/67000 Strasbourg/France (6 aut., 15 aut.); Sydney Institute for Astronomy, School of Physics A28, University of Sydney/NSW 2006/Australie (7 aut.); RSAA Australian National University, Mount Stromlo Observatory, Cotter Road, Weston Creek/Canberra, ACT 2611/Australie (8 aut.); Jeremiah Horrocks Institute for Astrophysics & Super-computing, University of Central Lancashire/Preston PR1 2HE/Royaume-Uni (9 aut.); Department of Astronomy & Physics, Saint Marys University/Halifax B3H 3C3/Canada (9 aut.); INAF Osservatorio Astronomico di Padova, Via dell'Osservatorio 8/36012 Asiago/Italie (10 aut.); Department of Physics and Astronomy, University of Victoria, P.O. Box 3055, Station CSC/Victoria, BC V8W 3P6/Canada (11 aut.); Australian Astronomical Observatory/Coonabarabran, NSW 2357/Australie (12 aut., 18 aut.); Department of Physics and Astronomy, Macquarie University/Sydney, NSW 2109/Australie (12 aut., 13 aut.); Macquarie Research Centre for Astronomy, Astrophysics & Astrophotonics, Macquarie University/Sydney, NSW 2109/Australie (12 aut.); Mullard Space Science Laboratory, University College London, Holmbury St. Mary/Dorking RH5 6NT/Royaume-Uni (14 aut.); Department of Astronomy, Padova University, Vicolo dell'Osservatorio 2/35122 Padova/Italie (16 aut.); Leibniz-Institut für Astrophysik Potsdam (AIP), An der Sternwarte 16/14482 Potsdam/Allemagne (16 aut., 17 aut., 19 aut.); Faculty of Mathematics and Physics, University of Ljubljana, Jadranska 19/1000 Ljubljana/Slovénie (20 aut.); Center of Excellence SPACE-SI, Askerceva cesta 12/1000 Ljubljana/Slovénie (20 aut.)</AF><DT>Publication en série; Niveau analytique</DT><SO>The Astrophysical journal; ISSN 0004-637X; Coden ASJOAB; Royaume-Uni; Da. 2011; Vol. 743; No. 2 p. 1; 107.1-107.14; Bibl. 3/4 p.</SO><LA>Anglais</LA><EA>We report the discovery of eight lithium-rich field giants found in a high-resolution spectroscopic sample of over 700 metal-poor stars ([Fe/H] < -0.5) selected from the Radial Velocity Experiment survey. The majority of the Li-rich giants in our sample are very metal-poor ([Fe/H] ? -1.9), and have a Li abundance (in the form of 7Li), A(Li) = log(n(Li)/n(H)) + 12, between 2.30 and 3.63, well above the typical upper red giant branch (RGB) limit, A(Li) < 0.5, while two stars, with A(Li) ˜ 1.7-1.8, show similar lithium abundances to normal giants at the same gravity. We further included two metal-poor, Li-rich globular cluster giants in our sample, namely the previously discovered M3-IV101 and newly discovered (in this work) M68-A96. This comprises the largest sample of metal-poor Li-rich giants to date. We performed a detailed abundance analysis of all stars, finding that the majority of our sample stars have elemental abundances similar to that of Li-normal halo giants. Although the evolutionary phase of each Li-rich giant cannot be definitively determined, the Li-rich phase is likely connected to extra mixing at the RGB bump or early asymptotic giant branch that triggers cool bottom processing in which the bottom of the outer convective envelope is connected to the H-burning shell in the star. The surface of a star becomes Li-enhanced as 7Be (which burns to 7Li) is transported to the stellar surface via the Cameron-Fowler mechanism. We discuss and discriminate among several models for the extra mixing that can cause Li production, given the detailed abundances of the Li-rich giants in our sample.</EA><CC>001E03</CC><FD>Vitesse radiale; Etoile pauvre en métal; Abondance stellaire; Géante rouge; Gravité; Amas globulaire; Abondance élément; Mélangeage; Branche géante asymptotique; Enveloppe convective; Etoile enveloppe; Modèle; Etoile type avancé; Population type II; Amas stellaire</FD><ED>Radial velocity; Metal-poor stars; Stellar abundance; Red giant stars; Gravity; Globular clusters; Element abundance; Mixing; Asymptotic giant branch; Convective shell; Shell stars; Models; Late type stars; Population II; Star clusters</ED><SD>Abundancia estelar; Rama gigante asintótica; Cubierta convectiva; Modelo; Población estelar II</SD><LO>INIST-512.354000506045870090</LO><ID>12-0058031</ID></server></inist></record>Pour manipuler ce document sous Unix (Dilib)
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