Optimization Methods Applied to Stellar Astrophysics
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Directed Follow-Up Strategy of Low-Cadence Photometric Surveys In
Mon. Not. R. Astron. Soc. 000, 1–11 (2011) Printed 5 November 2018 (MN LATEX style file v2.2) Directed follow-up strategy of low-cadence photometric surveys in Search of transiting exoplanets - I. Bayesian approach for adaptive scheduling Yifat Dzigan1⋆ and Shay Zucker1† 1Department of Geophysics and Planetary Sciences, Tel Aviv University, Tel Aviv 69978, Israel Accepted for publication in Monthly Notices of the Royal Astronomical Society Main Journal. Accepted 2011 April 8. ABSTRACT We propose a novel approach to utilize low-cadence photometric surveys for exoplan- etary transit search. Even if transits are undetectable in the survey database alone, it can still be useful for finding preferred times for directed follow-up observations that will maximize the chances to detect transits. We demonstrate the approach through a few simulated cases. These simulations are based on the Hipparcos Epoch Photometry data base, and the transiting planets whose transits were already detected there. In principle, the approach we propose will be suitable for the directed follow-up of the photometry from the planned Gaia mission, and it can hopefully significantly increase the yield of exoplanetary transits detected, thanks to Gaia. Key words: methods: data analysis – methods: observational – methods: statistical – techniques: photometric – surveys – planetary systems. 1 INTRODUCTION 2002). Thus the posterior detections motivated us to re- examine Hipparcos Epoch Photometry data and to look for a The idea to detect transits of exoplanets in the Hip- way to utilize this survey and similar low-cadence photomet- parcos Epoch Photometry (ESA 1997) trigerred several ric surveys, to detect exoplanets. The approach we propose studies that checked the feasibility of such an attempt. -
Stability of Planets in Binary Star Systems
StabilityStability ofof PlanetsPlanets inin BinaryBinary StarStar SystemsSystems Ákos Bazsó in collaboration with: E. Pilat-Lohinger, D. Bancelin, B. Funk ADG Group Outline Exoplanets in multiple star systems Secular perturbation theory Application: tight binary systems Summary + Outlook About NFN sub-project SP8 “Binary Star Systems and Habitability” Stand-alone project “Exoplanets: Architecture, Evolution and Habitability” Basic dynamical types S-type motion (“satellite”) around one star P-type motion (“planetary”) around both stars Image: R. Schwarz Exoplanets in multiple star systems Observations: (Schwarz 2014, Binary Catalogue) ● 55 binary star systems with 81 planets ● 43 S-type + 12 P-type systems ● 10 multiple star systems with 10 planets Example: γ Cep (Hatzes et al. 2003) ● RV measurements since 1981 ● Indication for a “planet” (Campbell et al. 1988) ● Binary period ~57 yrs, planet period ~2.5 yrs Multiplicity of stars ~45% of solar like stars (F6 – K3) with d < 25 pc in multiple star systems (Raghavan et al. 2010) Known exoplanet host stars: single double triple+ source 77% 20% 3% Raghavan et al. (2006) 83% 15% 2% Mugrauer & Neuhäuser (2009) 88% 10% 2% Roell et al. (2012) Exoplanet catalogues The Extrasolar Planets Encyclopaedia http://exoplanet.eu Exoplanet Orbit Database http://exoplanets.org Open Exoplanet Catalogue http://www.openexoplanetcatalogue.com The Planetary Habitability Laboratory http://phl.upr.edu/home NASA Exoplanet Archive http://exoplanetarchive.ipac.caltech.edu Binary Catalogue of Exoplanets http://www.univie.ac.at/adg/schwarz/multiple.html Habitable Zone Gallery http://www.hzgallery.org Binary Catalogue Binary Catalogue of Exoplanets http://www.univie.ac.at/adg/schwarz/multiple.html Dynamical stability Stability limit for S-type planets Rabl & Dvorak (1988), Holman & Wiegert (1999), Pilat-Lohinger & Dvorak (2002) Parameters (a , e , μ) bin bin Outer limit at roughly max. -
Naming the Extrasolar Planets
Naming the extrasolar planets W. Lyra Max Planck Institute for Astronomy, K¨onigstuhl 17, 69177, Heidelberg, Germany [email protected] Abstract and OGLE-TR-182 b, which does not help educators convey the message that these planets are quite similar to Jupiter. Extrasolar planets are not named and are referred to only In stark contrast, the sentence“planet Apollo is a gas giant by their assigned scientific designation. The reason given like Jupiter” is heavily - yet invisibly - coated with Coper- by the IAU to not name the planets is that it is consid- nicanism. ered impractical as planets are expected to be common. I One reason given by the IAU for not considering naming advance some reasons as to why this logic is flawed, and sug- the extrasolar planets is that it is a task deemed impractical. gest names for the 403 extrasolar planet candidates known One source is quoted as having said “if planets are found to as of Oct 2009. The names follow a scheme of association occur very frequently in the Universe, a system of individual with the constellation that the host star pertains to, and names for planets might well rapidly be found equally im- therefore are mostly drawn from Roman-Greek mythology. practicable as it is for stars, as planet discoveries progress.” Other mythologies may also be used given that a suitable 1. This leads to a second argument. It is indeed impractical association is established. to name all stars. But some stars are named nonetheless. In fact, all other classes of astronomical bodies are named. -
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A&A 646, A77 (2021) Astronomy https://doi.org/10.1051/0004-6361/202039765 & c ESO 2021 Astrophysics Stellar chromospheric activity of 1674 FGK stars from the AMBRE-HARPS sample I. A catalogue of homogeneous chromospheric activity? J. Gomes da Silva1, N. C. Santos1,2, V. Adibekyan1,2, S. G. Sousa1, T. L. Campante1,2, P. Figueira3,1, D. Bossini1, E. Delgado-Mena1, M. J. P. F. G. Monteiro1,2, P. de Laverny4, A. Recio-Blanco4, and C. Lovis5 1 Instituto de Astrofísica e Ciências do Espaço, Universidade do Porto, CAUP, Rua das Estrelas, 4150-762 Porto, Portugal e-mail: [email protected] 2 Departamento de Fiísica e Astronomia, Faculdade de Ciências, Universidade do Porto, 4169-007 Porto, Portugal 3 European Southern Observatory, Alonso de Cordova 3107, Vitacura, Santiago, Chile 4 Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Nice, France 5 Observatoire Astronomique de l’Université de Genève, 51 Ch. des Maillettes, 1290 Versoix, Switzerland Received 26 October 2020 / Accepted 15 December 2020 ABSTRACT Aims. The main objective of this project is to characterise chromospheric activity of FGK stars from the HARPS archive. We start, in this first paper, by presenting a catalogue of homogeneously determined chromospheric emission (CE), stellar atmospheric parameters, and ages for 1674 FGK main sequence (MS), subgiant, and giant stars. The analysis of CE level and variability is also performed. Methods. We measured CE in the Ca ii H&K lines using more than 180 000 high-resolution spectra from the HARPS spectrograph, as compiled in the AMBRE project, obtained between 2003 and 2019. -
Dynamics and Stability of Resonant Rings in Galaxies B
Astronomy Reports, Vol. 44, No. 5, 2000, pp. 279–285. Translated from Astronomicheskiœ Zhurnal, Vol. 77, No. 5, 2000, pp. 323–330. Original Russian Text Copyright © 2000 by Kondrat’ev. Dynamics and Stability of Resonant Rings in Galaxies B. P. Kondrat’ev Udmurt State University, Krasnoarmeœskaya ul. 71, Izhevsk, 426034 Russia Received December 24, 1998 Abstract—We have developed a model for a spheroidal, ring-shaped galaxy. The stars move in a ring with an elliptical cross section at the 1 : 1 frequency resonance. The shape of the cross section of the equilibrium ring depends on the oblateness of the galaxy itself, so that the ellipse of the ring cross section is radially extended when the oblateness of the galaxy is small. If the oblateness of galaxy exceeds some critical value, the ellipse cross section is extended along the Ox3 axis. The shape of the ring cross section is circular for a galaxy with critical eccentricity. The stability of the ring over a wide range of perturbations is studied. A fundamental bicu- bic dispersion equation for the frequencies of small oscillations of a perturbed ring is derived. Application of the model to the ring galaxy NGC 7020 shows that its ring cross section should be approximately circular. Anal- ysis of the dispersion equation demonstrates that stellar orbits in the arm are unstable (but the instability incre- ment is small). We conclude that stars in the ring of this galaxy should drift from the 1 : 1 resonance, and the ring itself should evolve. © 2000 MAIK “Nauka/Interperiodica”. 1. INTRODUCTION appearance of various commensurability ratios. -
Public HARPS Radial Velocity Database Corrected for Systematic
A&A 636, A74 (2020) Astronomy https://doi.org/10.1051/0004-6361/201936686 & c T. Trifonov et al. 2020 Astrophysics Public HARPS radial velocity database corrected for systematic errors?,?? Trifon Trifonov1,2, Lev Tal-Or3,4, Mathias Zechmeister5, Adrian Kaminski6, Shay Zucker4, and Tsevi Mazeh7 1 Max-Planck-Institut für Astronomie, Königstuhl 17, 69117 Heidelberg, Germany e-mail: [email protected] 2 Department of Astronomy, Sofia University “St Kliment Ohridski”, 5 James Bourchier Blvd, 1164 Sofia, Bulgaria 3 Department of Physics, Ariel University, Ariel 40700, Israel 4 Department of Geophysics, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 6997801, Israel 5 Institut für Astrophysik, Georg-August-Universität, Friedrich-Hund-Platz 1, 37077 Göttingen, Germany 6 Landessternwarte, Zentrum für Astronomie der Universtät Heidelberg, Königstuhl 12, 69117 Heidelberg, Germany 7 School of Physics and Astronomy, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 6997801, Israel Received 11 September 2019 / Accepted 16 January 2020 ABSTRACT Context. The High Accuracy Radial velocity Planet Searcher (HARPS) spectrograph has been mounted since 2003 at the ESO 3.6 m telescope in La Silla and provides state-of-the-art stellar radial velocity (RV) measurements with a precision down to ∼1 m s−1. The spectra are extracted with a dedicated data-reduction software (DRS), and the RVs are computed by cross-correlating with a numerical mask. Aims. This study has three main aims: (i) Create easy access to the public HARPS RV data set. (ii) Apply the new public SpEctrum Radial Velocity AnaLyser (SERVAL) pipeline to the spectra, and produce a more precise RV data set. -
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A&A 562, A92 (2014) Astronomy DOI: 10.1051/0004-6361/201321493 & c ESO 2014 Astrophysics Li depletion in solar analogues with exoplanets Extending the sample, E. Delgado Mena1,G.Israelian2,3, J. I. González Hernández2,3,S.G.Sousa1,2,4, A. Mortier1,4,N.C.Santos1,4, V. Zh. Adibekyan1, J. Fernandes5, R. Rebolo2,3,6,S.Udry7, and M. Mayor7 1 Centro de Astrofísica, Universidade do Porto, Rua das Estrelas, 4150-762 Porto, Portugal e-mail: [email protected] 2 Instituto de Astrofísica de Canarias, C/ Via Lactea s/n, 38200 La Laguna, Tenerife, Spain 3 Departamento de Astrofísica, Universidad de La Laguna, 38205 La Laguna, Tenerife, Spain 4 Departamento de Física e Astronomia, Faculdade de Ciências, Universidade do Porto, 4169-007 Porto, Portugal 5 CGUC, Department of Mathematics and Astronomical Observatory, University of Coimbra, 3049 Coimbra, Portugal 6 Consejo Superior de Investigaciones Científicas, CSIC, Spain 7 Observatoire de Genève, Université de Genève, 51 ch. des Maillettes, 1290 Sauverny, Switzerland Received 18 March 2013 / Accepted 25 November 2013 ABSTRACT Aims. We want to study the effects of the formation of planets and planetary systems on the atmospheric Li abundance of planet host stars. Methods. In this work we present new determinations of lithium abundances for 326 main sequence stars with and without planets in the Teff range 5600–5900 K. The 277 stars come from the HARPS sample, the remaining targets were observed with a variety of high-resolution spectrographs. Results. We confirm significant differences in the Li distribution of solar twins (Teff = T ± 80 K, log g = log g ± 0.2and[Fe/H] = [Fe/H] ±0.2): the full sample of planet host stars (22) shows Li average values lower than “single” stars with no detected planets (60). -
Arxiv:2105.11583V2 [Astro-Ph.EP] 2 Jul 2021 Keck-HIRES, APF-Levy, and Lick-Hamilton Spectrographs
Draft version July 6, 2021 Typeset using LATEX twocolumn style in AASTeX63 The California Legacy Survey I. A Catalog of 178 Planets from Precision Radial Velocity Monitoring of 719 Nearby Stars over Three Decades Lee J. Rosenthal,1 Benjamin J. Fulton,1, 2 Lea A. Hirsch,3 Howard T. Isaacson,4 Andrew W. Howard,1 Cayla M. Dedrick,5, 6 Ilya A. Sherstyuk,1 Sarah C. Blunt,1, 7 Erik A. Petigura,8 Heather A. Knutson,9 Aida Behmard,9, 7 Ashley Chontos,10, 7 Justin R. Crepp,11 Ian J. M. Crossfield,12 Paul A. Dalba,13, 14 Debra A. Fischer,15 Gregory W. Henry,16 Stephen R. Kane,13 Molly Kosiarek,17, 7 Geoffrey W. Marcy,1, 7 Ryan A. Rubenzahl,1, 7 Lauren M. Weiss,10 and Jason T. Wright18, 19, 20 1Cahill Center for Astronomy & Astrophysics, California Institute of Technology, Pasadena, CA 91125, USA 2IPAC-NASA Exoplanet Science Institute, Pasadena, CA 91125, USA 3Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, Stanford, CA 94305, USA 4Department of Astronomy, University of California Berkeley, Berkeley, CA 94720, USA 5Cahill Center for Astronomy & Astrophysics, California Institute of Technology, Pasadena, CA 91125, USA 6Department of Astronomy & Astrophysics, The Pennsylvania State University, 525 Davey Lab, University Park, PA 16802, USA 7NSF Graduate Research Fellow 8Department of Physics & Astronomy, University of California Los Angeles, Los Angeles, CA 90095, USA 9Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA 10Institute for Astronomy, University of Hawai`i, -
Arxiv:1709.05344V1 [Astro-Ph.SR] 15 Sep 2017 (A(Li) = 2.75), Higher Than Its Companion by 0.5 Dex
Draft version September 19, 2017 Typeset using LATEX modern style in AASTeX61 KRONOS & KRIOS: EVIDENCE FOR ACCRETION OF A MASSIVE, ROCKY PLANETARY SYSTEM IN A COMOVING PAIR OF SOLAR-TYPE STARS Semyeong Oh,1, 2 Adrian M. Price-Whelan,1 John M. Brewer,3, 4 David W. Hogg,5, 6, 7, 8 David N. Spergel,1, 5 and Justin Myles3 1Department of Astrophysical Sciences, Princeton University, 4 Ivy Lane, Princeton, NJ 08544, USA 2To whom correspondence should be addressed: [email protected] 3Department of Astronomy, Yale University, 260 Whitney Ave, New Haven, CT 06511, USA 4Department of Astronomy, Columbia University, 550 West 120th Street, New York, NY 10027, USA 5Center for Computational Astrophysics, Flatiron Institute, 162 Fifth Ave, New York, NY 10010, USA 6Center for Cosmology and Particle Physics, Department of Physics, New York University, 726 Broadway, New York, NY 10003, USA 7Center for Data Science, New York University, 60 Fifth Ave, New York, NY 10011, USA 8Max-Planck-Institut f¨ur Astronomie, K¨onigstuhl17, D-69117 Heidelberg ABSTRACT We report and discuss the discovery of a comoving pair of bright solar-type stars, HD 240430 and HD 240429, with a significant difference in their chemical abundances. The two stars have an estimated 3D separation of ≈ 0:6 pc (≈ 0:01 pc projected) at a distance of r ≈ 100 pc with nearly identical three-dimensional velocities, as inferred from Gaia TGAS parallaxes and proper motions, and high-precision radial velocity measurements. Stellar parameters determined from high-resolution Keck HIRES spectra indicate that both stars are ∼ 4 Gyr old. The more metal-rich of the two, HD 240430, shows an enhancement of refractory (TC > 1200 K) elements by ≈ 0:2 dex and a marginal enhancement of (moderately) volatile elements (TC < 1200 K; C, N, O, Na, and Mn). -
Exoplanet.Eu Catalog Page 1 # Name Mass Star Name
exoplanet.eu_catalog # name mass star_name star_distance star_mass OGLE-2016-BLG-1469L b 13.6 OGLE-2016-BLG-1469L 4500.0 0.048 11 Com b 19.4 11 Com 110.6 2.7 11 Oph b 21 11 Oph 145.0 0.0162 11 UMi b 10.5 11 UMi 119.5 1.8 14 And b 5.33 14 And 76.4 2.2 14 Her b 4.64 14 Her 18.1 0.9 16 Cyg B b 1.68 16 Cyg B 21.4 1.01 18 Del b 10.3 18 Del 73.1 2.3 1RXS 1609 b 14 1RXS1609 145.0 0.73 1SWASP J1407 b 20 1SWASP J1407 133.0 0.9 24 Sex b 1.99 24 Sex 74.8 1.54 24 Sex c 0.86 24 Sex 74.8 1.54 2M 0103-55 (AB) b 13 2M 0103-55 (AB) 47.2 0.4 2M 0122-24 b 20 2M 0122-24 36.0 0.4 2M 0219-39 b 13.9 2M 0219-39 39.4 0.11 2M 0441+23 b 7.5 2M 0441+23 140.0 0.02 2M 0746+20 b 30 2M 0746+20 12.2 0.12 2M 1207-39 24 2M 1207-39 52.4 0.025 2M 1207-39 b 4 2M 1207-39 52.4 0.025 2M 1938+46 b 1.9 2M 1938+46 0.6 2M 2140+16 b 20 2M 2140+16 25.0 0.08 2M 2206-20 b 30 2M 2206-20 26.7 0.13 2M 2236+4751 b 12.5 2M 2236+4751 63.0 0.6 2M J2126-81 b 13.3 TYC 9486-927-1 24.8 0.4 2MASS J11193254 AB 3.7 2MASS J11193254 AB 2MASS J1450-7841 A 40 2MASS J1450-7841 A 75.0 0.04 2MASS J1450-7841 B 40 2MASS J1450-7841 B 75.0 0.04 2MASS J2250+2325 b 30 2MASS J2250+2325 41.5 30 Ari B b 9.88 30 Ari B 39.4 1.22 38 Vir b 4.51 38 Vir 1.18 4 Uma b 7.1 4 Uma 78.5 1.234 42 Dra b 3.88 42 Dra 97.3 0.98 47 Uma b 2.53 47 Uma 14.0 1.03 47 Uma c 0.54 47 Uma 14.0 1.03 47 Uma d 1.64 47 Uma 14.0 1.03 51 Eri b 9.1 51 Eri 29.4 1.75 51 Peg b 0.47 51 Peg 14.7 1.11 55 Cnc b 0.84 55 Cnc 12.3 0.905 55 Cnc c 0.1784 55 Cnc 12.3 0.905 55 Cnc d 3.86 55 Cnc 12.3 0.905 55 Cnc e 0.02547 55 Cnc 12.3 0.905 55 Cnc f 0.1479 55 -
New Low-Mass Stellar Companions of the Exoplanet Host Stars HD 125612 and HD 212301 M
A&A 494, 373–378 (2009) Astronomy DOI: 10.1051/0004-6361:200810639 & c ESO 2009 Astrophysics The multiplicity of exoplanet host stars New low-mass stellar companions of the exoplanet host stars HD 125612 and HD 212301 M. Mugrauer and R. Neuhäuser Astrophysikalisches Institut und Universitäts-Sternwarte Jena, Schillergäßchen 2-3, 07745 Jena, Germany e-mail: [email protected] Received 18 July 2008 / Accepted 31 October 2008 ABSTRACT Aims. We present new results from our ongoing multiplicity study of exoplanet host stars, carried out with SofI/NTT. We provide the most recent list of confirmed binary and triple star systems that harbor exoplanets. Methods. We use direct imaging to identify wide stellar and substellar companions as co-moving objects to the observed exoplanet host stars, whose masses and spectral types are determined with follow-up photometry and spectroscopy. Results. We found two new co-moving companions of the exoplanet host stars HD 125612 and HD 212301. HD 125612 B is a wide M 4 dwarf (0.18 M) companion of the exoplanet host star HD 125612, located about 1.5 arcmin (∼4750 AU of projected separation) south-east of its primary. In contrast, HD 212301 B is a close M 3 dwarf (0.35 M), which is found about 4.4 arcsec (∼230 AU of projected separation) north-west of its primary. Conclusions. The binaries HD 125612 AB and HD 212301 AB are new members in the continuously growing list of exoplanet host star systems of which 43 are presently known. Hence, the multiplicity rate of exoplanet host stars is about 17%. -
The HARPS Search for Southern Extra-Solar Planets
The HARPS search for southern extra-solar planets. III. Three Saturn-mass planets around HD 93083, HD 101930 and HD 102117 C. Lovis, M. Mayor, François Bouchy, F. Pepe, D. Queloz, N. C. Santos, S. Udry, W. Benz, Jean-Loup Bertaux, C. Mordasini, et al. To cite this version: C. Lovis, M. Mayor, François Bouchy, F. Pepe, D. Queloz, et al.. The HARPS search for southern extra-solar planets. III. Three Saturn-mass planets around HD 93083, HD 101930 and HD 102117. Astronomy and Astrophysics - A&A, EDP Sciences, 2005, 437 (3), pp.1121-1126. 10.1051/0004- 6361:20052864. hal-00017981 HAL Id: hal-00017981 https://hal.archives-ouvertes.fr/hal-00017981 Submitted on 17 Jan 2021 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. A&A 437, 1121–1126 (2005) Astronomy DOI: 10.1051/0004-6361:20052864 & c ESO 2005 Astrophysics The HARPS search for southern extra-solar planets III. Three Saturn-mass planets around HD 93083, HD 101930 and HD 102117 C. Lovis1, M. Mayor1, F. Bouchy2,F.Pepe1,D.Queloz1,N.C.Santos3,1, S. Udry1,W.Benz4, J.-L. Bertaux5, C.