Abundance Pattern of the Chemically Peculiar Star Feh-Duf
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A&A 531, A133 (2011) Astronomy DOI: 10.1051/0004-6361/201014213 & c ESO 2011 Astrophysics High-resolution spectroscopic observations of the metal-poor, chemically peculiar, and high velocity Fehrenbach & Duflot star, N. A. Drake1 and C. B. Pereira2 1 Sobolev Astronomical Institute, St. Petersburg State University, Universitetski pr. 28, St. Petersburg 198504, Russia 2 Observatório Nacional, Rua José Cristino, 77, CEP 20921-400, São Cristóvão, Rio de Janeiro-RJ, Brazil e-mail: [drake,claudio]@on.br Received 6 February 2010 / Accepted 5 May 2011 ABSTRACT Aims. We determine the atmospheric parameters and abundance pattern of the chemically peculiar metal-poor Fehrenbach & Duflot (Feh-Duf) star to more clearly understand its evolutionary state and the nature of the s-element enhancement in this star. Methods. Its atmospheric parameters and chemical abundances were determined using high resolution optical spectroscopy and employing the local-thermodynamic-equilibrium model atmospheres of Kurucz and spectral analysis code MOOG. Results. The derived abundances show that the Feh-Duf star is a low-metallicity ([Fe/H] = −1.93) star with high carbon and heavy s-element abundances, while the abundance of the light s-process element yttrium is low ([Y/Fe] = −0.07). The oxygen abundance is lower than for Galactic halo stars of similar metallicity.We conclude that the Feh-Duf star could be a CH star with C/O = 1.3. Another possibility is that the Feh-Duf star could be an early-AGB star. The Fehrenbach & Duflot star is also a lead star with [Pb/Ce] =+0.69. −1 In addition, it displays an extreme retrograde motion (VGRF = −259 km s ), which in combination with its underabundance of α-elements suggests that this star may have been captured by the Milky Way galaxy. -
Orbit of the Mercury-Manganese Binary 41 Eridani? C
A&A 600, L5 (2017) Astronomy DOI: 10.1051/0004-6361/201730414 & c ESO 2017 Astrophysics Letter to the Editor Orbit of the mercury-manganese binary 41 Eridani? C. A. Hummel1, M. Schöller1, G. Duvert2, and S. Hubrig3 1 European Southern Observatory, Karl-Schwarzschild-Str. 2, 85748 Garching, Germany e-mail: [email protected] 2 UJF-Grenoble 1/CNRS-INSU, Institut de Planétologie et d’Astrophysique de Grenoble, UMR 5274, 38041 Grenoble, France 3 Leibniz-Institut für Astrophysik Potsdam, An der Sternwarte 16, 14482 Potsdam, Germany Received 10 January 2017 / Accepted 1 March 2017 ABSTRACT Context. Mercury-manganese (HgMn) stars are a class of slowly rotating chemically peculiar main-sequence late B-type stars. More than two-thirds of the HgMn stars are known to belong to spectroscopic binaries. Aims. By determining orbital solutions for binary HgMn stars, we will be able to obtain the masses for both components and the distance to the system. Consequently, we can establish the position of both components in the Hertzsprung-Russell diagram and confront the chemical peculiarities of the HgMn stars with their age and evolutionary history. Methods. We initiated a program to identify interferometric binaries in a sample of HgMn stars, using the PIONIER near-infrared interferometer at the VLTI on Cerro Paranal, Chile. For the detected systems, we intend to obtain full orbital solutions in conjunction with spectroscopic data. Results. The data obtained for the SB2 system 41 Eridani allowed the determination of the orbital elements with a period of just five days and a semi-major axis of under 2 mas. -
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N O T I C E THIS DOCUMENT HAS BEEN REPRODUCED FROM MICROFICHE. ALTHOUGH IT IS RECOGNIZED THAT CERTAIN PORTIONS ARE ILLEGIBLE, IT IS BEING RELEASED IN THE INTEREST OF MAKING AVAILABLE AS MUCH INFORMATION AS POSSIBLE P993-198422 International Collogium on Atomic Spectra and Oscillator Strengths for Astrophysical and Laboratory Plasmas (4th) Held at the National institute of Standards and Technology Gaithersburg, Maryland on September 14-17, 1992 (U.S.) National inst. of Standards and Technology (PL) Gaithersburg, MD Apr 93 US. DEPARTMENT OF COMMERCE Ndioul Techcical IMermeNON Service B•11G 2-10i1A2 2 MIST-1 /4 U.S. VZPARTMENT OF COMMERCE (REV. NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY M GONTSOLw1N^BENN O4" COMM 4M /. MANUSCRIPT REVIEW AND APPROVAL "KIST/ p-850 ^' THIS NSTRUCTWNS: ATTACH ORIGINAL OF FORM TO ONE (1) COPY OF MANUSCIIN IT AND SEINE TO: PUBLICATIOM OATS NUMBER PRINTED PAGES April 1993 199 HE SECRETAIIY, APPROPRIATE EDITO RIAL REVIEW BOARD. ITLE AND SUBTITLE (CITE NN PULL) 4rh International Colloquium on Atomic Spectra and Oscillator Strengths for Astrophysical and Laboratory Plasmas -- POSTER PAPERS :ONTIEACT OR GRANT NUMBER TYPE OF REPORT AND/OR PERIOD COMM UTHOR(S) (LAST %,TAME, POST NNITIAL, SECOND INITIAL) PERFORM" ORGANIZATION (CHECK (IQ ONE SOX) EDITORS XXX MIST/GAITHERSBUIIG Sugar, Jack and Leckrone, B:;vid INST/BODUM JILA BOIRDE11 "ORATORY AND DIVISION NAMES (FIRST MOST AUTHOR ONLY) Physics Laboratory/Atomic Physics Division 'PONSORING ORGANIZATION NAME AND COMPLETE ADDRESS TREET, CITY. STATE. ZNh ^y((S/ ,T AiL7A - -ASO IECOMMENDsO FOR MIST PUBLICATION JOVIAMAL OF RESEMICM (MIST JRES) CIONOGRAPK (MIST MN) LETTER CIRCULAR J. PHYS. A CHEM. -
CS 30322-023: an Ultra Metal-Poor TP-AGB Star?
Astronomy & Astrophysics manuscript no. 4802 c ESO 2018 September 7, 2018 CS 30322-023: an ultra metal-poor TP-AGB star?⋆ T. Masseron1, S. Van Eck2, B. Famaey2, S. Goriely2, B. Plez1, L. Siess2, T. C. Beers3, F. Primas4, and A. Jorissen2 1 GRAAL, UMR 5024 CNRS, Universit´ede Montpellier-II, France 2 Institut d’Astronomie et d’Astrophysique, Universit´eLibre de Bruxelles, CP 226, Boulevard du Triomphe, B-1050 Bruxelles, Belgium 3 Department of Physics and Astronomy, Center for the Study of Cosmic Evolution (CSCE) and Joint Institute for Nuclear Astrophysics (JINA), Michigan State University, East Lansing, MI 48824-1116, USA 4 European Southern Observatory, K. Schwarzschild Straße 2, D-85748 Garching bei M¨unchen Received January 3, 2006 / Accepted May 5, 2006 ABSTRACT Context. The remarkable properties of CS 30322-023 became apparent during the course of a high-resolution spectroscopic study of a sample of 23 carbon-enhanced, metal-poor (CEMP) stars. Aims. This sample is studied in order to gain a better understanding of s- and r-process nucleosynthesis at low metallicity, and to investigate the role of duplicity. Methods. High-resolution UVES spectra have been obtained, and abundances are derived using 1-D, plane-parallel OSMARCS models under the LTE hypothesis. The derived atmospheric parameters and observed abundances are compared to evolutionary tracks and nucleosynthesis predictions to infer the evolutionary status of CS 30322-023. Results. CS 30322-023 is remarkable in having the lowest surface gravity (log g ≤ −0.3) among the metal-poor stars studied to date. As a result of its rather low temperature (4100 K), abundances could be derived for 35 chemical elements; the abundance pattern of CS 30322-023 is one of the most well-specified of all known extremely metal-poor stars. -
Chandra X-Ray Study Confirms That the Magnetic Standard Ap Star KQ Vel
A&A 641, L8 (2020) Astronomy https://doi.org/10.1051/0004-6361/202038214 & c ESO 2020 Astrophysics LETTER TO THE EDITOR Chandra X-ray study confirms that the magnetic standard Ap star KQ Vel hosts a neutron star companion? Lidia M. Oskinova1,2, Richard Ignace3, Paolo Leto4, and Konstantin A. Postnov5,2 1 Institute for Physics and Astronomy, University Potsdam, 14476 Potsdam, Germany e-mail: [email protected] 2 Department of Astronomy, Kazan Federal University, Kremlevskaya Str 18, Kazan, Russia 3 Department of Physics & Astronomy, East Tennessee State University, Johnson City, TN 37614, USA 4 NAF – Osservatorio Astrofisico di Catania, Via S. Sofia 78, 95123 Catania, Italy 5 Sternberg Astronomical Institute, M.V. Lomonosov Moscow University, Universitetskij pr. 13, 119234 Moscow, Russia Received 20 April 2020 / Accepted 20 July 2020 ABSTRACT Context. KQ Vel is a peculiar A0p star with a strong surface magnetic field of about 7.5 kG. It has a slow rotational period of nearly 8 years. Bailey et al. (A&A, 575, A115) detected a binary companion of uncertain nature and suggested that it might be a neutron star or a black hole. Aims. We analyze X-ray data obtained by the Chandra telescope to ascertain information about the stellar magnetic field and/or interaction between the star and its companion. Methods. We confirm previous X-ray detections of KQ Vel with a relatively high X-ray luminosity of 2 × 1030 erg s−1. The X-ray spectra suggest the presence of hot gas at >20 MK and, possibly, of a nonthermal component. -
Fy10 Budget by Program
AURA/NOAO FISCAL YEAR ANNUAL REPORT FY 2010 Revised Submitted to the National Science Foundation March 16, 2011 This image, aimed toward the southern celestial pole atop the CTIO Blanco 4-m telescope, shows the Large and Small Magellanic Clouds, the Milky Way (Carinae Region) and the Coal Sack (dark area, close to the Southern Crux). The 33 “written” on the Schmidt Telescope dome using a green laser pointer during the two-minute exposure commemorates the rescue effort of 33 miners trapped for 69 days almost 700 m underground in the San Jose mine in northern Chile. The image was taken while the rescue was in progress on 13 October 2010, at 3:30 am Chilean Daylight Saving time. Image Credit: Arturo Gomez/CTIO/NOAO/AURA/NSF National Optical Astronomy Observatory Fiscal Year Annual Report for FY 2010 Revised (October 1, 2009 – September 30, 2010) Submitted to the National Science Foundation Pursuant to Cooperative Support Agreement No. AST-0950945 March 16, 2011 Table of Contents MISSION SYNOPSIS ............................................................................................................ IV 1 EXECUTIVE SUMMARY ................................................................................................ 1 2 NOAO ACCOMPLISHMENTS ....................................................................................... 2 2.1 Achievements ..................................................................................................... 2 2.2 Status of Vision and Goals ................................................................................ -
Pos(NIC-IX)062 C 13 ) and Different Fe
Light and heavy elements nucleosynthesis in low mass AGB Stars PoS(NIC-IX)062 Sergio Cristallo∗ Osservatorio Astronomico di Teramo (INAF) E-mail: [email protected] Oscar Straniero Osservatorio Astronomico di Teramo (INAF) E-mail: [email protected] Roberto Gallino Universitá degli studi di Torino, Dipartimento di Fisica Generale E-mail: [email protected] Luciano Piersanti Osservatorio Astronomico di Teramo (INAF) E-mail: [email protected] Inma Dominguéz Universidad de Granada E-mail: [email protected] We present a new set of low mass AGB star models having the same mass (2 M) and different metallicities. For each metallicity we follow the evolution from the Pre Main Sequence up to the end of the Thermally Pulsing AGB Phase. By means of an exponential decay of the convective velocities at the inner border of the convective envelope we obtain the formation of a tiny 13C pocket after Third Dredge Up episodes, whose extension in mass decreases along the AGB path. Detailed pulse by pulse surface enrichments and final yields at different metallicities, computed by using a full nuclear network coupled to the FRANEC stellar evolutionary code, are presented and discussed. We follow the production of both light and heavy elements describing nuclear chains responsible for their production and show new results for the synthesis of radioactive isotopes such as 26Al and 60Fe. International Symposium on Nuclear Astrophysics — Nuclei in the Cosmos — IX June 25-30 2006 CERN, Geneva, Switzerland ∗Speaker. c Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence. -
10252228.Pdf
ANKARA ÜNİVERSİTESİ FEN BİLİMLERİ ENSTİTÜSÜ DOKTORA TEZİ SEÇİLMİŞ BAZI PEKÜLER A YILDIZLARININ DOPPLER GÖRÜNTÜLEME YÖNTEMİ İLE YÜZEY HARİTALARININ ELDE EDİLMESİ S. Hande GÜRSOYTRAK ASTRONOMİ VE UZAY BİLİMLERİ ANABİLİM DALI ANKARA 2019 Her hakkı saklıdır ÖZET Doktora Tezi SEÇİLMİŞ BAZI PEKÜLER A YILDIZLARININ DOPPLER GÖRÜNTÜLEME YÖNTEMİ İLE YÜZEY HARİTALARININ ELDE EDİLMESİ S. Hande GÜRSOYTRAK Ankara Üniversitesi Fen Bilimleri Enstitüsü Astronomi ve Uzay Bilimleri Anabilim Dalı Danışman: Doç. Dr. Birol GÜROL Uzaklıkları nedeniyle ancak noktasal kaynak olarak görebildiğimiz yıldızların yüzeyindeki element bolluk dağılımlarının ortaya çıkarılabilmesi, astrofiziksel açıdan yıldızların iç dinamiklerinin anlaşılmasında son derece önemlidir. Bu çalışmada, A tayf türünden kimyasal peküler (Ap) yıldızlar; V776 Her, V354 Peg, 56 Tau ve EP UMa’nın tayfsal gözlemlerinden yararlanarak Doppler Görüntüleme tekniğiyle yüzey bollukları haritalandırılmıştır. Tayfsal gözlemler, TÜBİTAK Ulusal Gözlemevi (Antalya), 1.5 m’lik Rus-Türk Teleskobu’na bağlı (RTT150) Coude eşel tayfçekeri kullanılarak elde edilmiştir. Coude eşel tayfları 3690Å ile 10275Å dalgaboyu aralığını kapsamaktadır ve tayfsal çözünürlüğü 40000 civarındadır. Tayfların indirgenmesi IRAF (Image Reduction and Analysis Facility) programı kullanılarak gerçekleştirilmiştir. Çalışmanın temel hedefi olan Doppler görüntüleme tekniğinin gereksinimleri dikkate alınarak gözlemsel tayflar peküler yıldızların dönme dönemlerinin zaman serileri şeklinde alınmıştır. EP UMa için elde edilen tayf sayısı Doppler -
Investigation for the Puzzling Abundance Pattern of the Neutron
To appear in T he Astrophysical Journal Investigation for the puzzling abundance pattern of the neutron-capture elements in the ultra metal-poor star: CS 30322-023 Wen-Yuan Cui1,2, Bo Zhang1,2,4, Kun Ma1 and Lu Zhang3 1Department of Physics, Hebei Normal University, 113 Yuhua Dong Road, Shijiazhuang 050016, P.R.China; [email protected] 2National Astronomical observatories, Chinese Academy of Sciences, 20A Datun Road, Chaoyang District, Beijing 100012, P.R.China; [email protected] 3Department of Modern Physics, University of Science and Technology of China, Hefei 230026, P.R.China; zhang8899−[email protected] ABSTRACT The s-enhanced and very metal-poor star CS 30322-023 shows a puzzling arXiv:astro-ph/0702676v1 26 Feb 2007 abundance pattern of the neutron-capture elements, i.e. several neutron-capture elements such as Ba, Pb etc. show enhancement, but other neutron-capture elements such as Sr, Eu etc. exhibit deficient with respect to iron. The study to this sample star could make people gain a better understanding of s- and r-process nucleosynthesis at low metallicity. Using a parametric model, we find that the abundance pattern of the neutron-capture elements could be best explained by a star that was polluted by an AGB star and the CS 30322-023 binary system formed in a molecular cloud which had never been polluted by r-process material. The lack of r-process material also indicates that the AGB companion cannot have undergone a type-1.5 supernova, and thus must have had an initial mass 4 Corresponding author. -
KELT-17: a Chemically Peculiar Am Star and a Hot-Jupiter Planet
manuscript no. saffe c 2020 July 29, 2020 KELT-17: a chemically peculiar Am star and a hot-Jupiter planet⋆ C. Saffe1, 2, 6, P. Miquelarena1, 2, 6, J. Alacoria1, 6, J. F. González1, 2, 6, M. Flores1, 2, 6, M. Jaque Arancibia4, 5, D. Calvo2, E. Jofré7, 3, 6 and A. Collado1, 2, 6 1 Instituto de Ciencias Astronómicas, de la Tierra y del Espacio (ICATE-CONICET), C.C 467, 5400, San Juan, Argentina. 2 Universidad Nacional de San Juan (UNSJ), Facultad de Ciencias Exactas, Físicas y Naturales (FCEFN), San Juan, Argentina. 3 Observatorio Astronómico de Córdoba (OAC), Laprida 854, X5000BGR, Córdoba, Argentina. 4 Instituto de Investigación Multidisciplinar en Ciencia y Tecnología, Universidad de La Serena, Raúl Bitrán 1305, La Serena, Chile 5 Departamento de Física y Astronomía, Universidad de La Serena, Av. Cisternas 1200 N, La Serena, Chile. 6 Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina 7 Instituto de Astronomía, Universidad Nacional Autónoma de México, Ciudad Universitaria, CDMX, C.P. 04510, México Received xxx, xxx ; accepted xxxx, xxxx ABSTRACT Context. The detection of planets orbiting chemically peculiar stars is very scarcely known in the literature. Aims. To determine the detailed chemical composition of the remarkable planet host star KELT-17. This object hosts a hot-Jupiter planet with 1.31 MJup detected by transits, being one of the more massive and rapidly rotating planet hosts to date. We aimed to derive a complete chemical pattern for this star, in order to compare it with those of chemically peculiar stars. Methods. We carried out a detailed abundance determination in the planet host star KELT-17 via spectral synthesis. -
Constraining the Very Heavy Elemental Abundance Peak in the Chemically Peculiar Star Lupi, with New Atomic Data for Os II and Ir II
Constraining the very heavy elemental abundance peak in the chemically peculiar star Lupi, with new atomic data for Os II and Ir II Ivarsson, Stefan; Wahlgren, Glenn; Dai, Zhenwen; Lundberg, Hans; Leckrone, D S Published in: Astronomy & Astrophysics DOI: 10.1051/0004-6361:20040298 2004 Link to publication Citation for published version (APA): Ivarsson, S., Wahlgren, G., Dai, Z., Lundberg, H., & Leckrone, D. S. (2004). Constraining the very heavy elemental abundance peak in the chemically peculiar star χ Lupi, with new atomic data for Os II and Ir II. Astronomy & Astrophysics, 425(1), 353-360. https://doi.org/10.1051/0004-6361:20040298 Total number of authors: 5 General rights Unless other specific re-use rights are stated the following general rights apply: Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal Read more about Creative commons licenses: https://creativecommons.org/licenses/ Take down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. LUND UNIVERSITY PO Box 117 221 00 Lund +46 46-222 00 00 A&A 425, 353–360 (2004) Astronomy DOI: 10.1051/0004-6361:20040298 & c ESO 2004 Astrophysics Constraining the very heavy elemental abundance peak in the chemically peculiar star χ Lupi, with new atomic data for Os II and Ir II S. -