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Homogeneous Spectroscopic Parameters for Bright Planet Host Stars from the Northern Hemisphere the Impact on Stellar and Planetary Mass (Research Note)
A&A 576, A94 (2015) Astronomy DOI: 10.1051/0004-6361/201425227 & c ESO 2015 Astrophysics Homogeneous spectroscopic parameters for bright planet host stars from the northern hemisphere The impact on stellar and planetary mass (Research Note) S. G. Sousa1,2,N.C.Santos1,2, A. Mortier1,3,M.Tsantaki1,2, V. Adibekyan1, E. Delgado Mena1,G.Israelian4,5, B. Rojas-Ayala1,andV.Neves6 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 Física e Astronomia, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal 3 SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews KY16 9SS, UK 4 Instituto de Astrofísica de Canarias, 38200 La Laguna, Tenerife, Spain 5 Departamento de Astrofísica, Universidade de La Laguna, 38205 La Laguna, Tenerife, Spain 6 Departamento de Física, Universidade Federal do Rio Grande do Norte, Brazil Received 27 October 2014 / Accepted 19 February 2015 ABSTRACT Aims. In this work we derive new precise and homogeneous parameters for 37 stars with planets. For this purpose, we analyze high resolution spectra obtained by the NARVAL spectrograph for a sample composed of bright planet host stars in the northern hemisphere. The new parameters are included in the SWEET-Cat online catalogue. Methods. To ensure that the catalogue is homogeneous, we use our standard spectroscopic analysis procedure, ARES+MOOG, to derive effective temperatures, surface gravities, and metallicities. These spectroscopic stellar parameters are then used as input to compute the stellar mass and radius, which are fundamental for the derivation of the planetary mass and radius. -
December 2019 BRAS Newsletter
A Monthly Meeting December 11th at 7PM at HRPO (Monthly meetings are on 2nd Mondays, Highland Road Park Observatory). Annual Christmas Potluck, and election of officers. What's In This Issue? President’s Message Secretary's Summary Outreach Report Asteroid and Comet News Light Pollution Committee Report Globe at Night Member’s Corner – The Green Odyssey Messages from the HRPO Friday Night Lecture Series Science Academy Solar Viewing Stem Expansion Transit of Murcury Edge of Night Natural Sky Conference Observing Notes: Perseus – Rescuer Of Andromeda, or the Hero & Mythology Like this newsletter? See PAST ISSUES online back to 2009 Visit us on Facebook – Baton Rouge Astronomical Society Baton Rouge Astronomical Society Newsletter, Night Visions Page 2 of 25 December 2019 President’s Message I would like to thank everyone for having me as your president for the last two years . I hope you have enjoyed the past two year as much as I did. We had our first Members Only Observing Night (MOON) at HRPO on Sunday, 29 November,. New officers nominated for next year: Scott Cadwallader for President, Coy Wagoner for Vice- President, Thomas Halligan for Secretary, and Trey Anding for Treasurer. Of course, the nominations are still open. If you wish to be an officer or know of a fellow member who would make a good officer contact John Nagle, Merrill Hess, or Craig Brenden. We will hold our annual Baton Rouge “Gastronomical” Society Christmas holiday feast potluck and officer elections on Monday, December 9th at 7PM at HRPO. I look forward to seeing you all there. ALCon 2022 Bid Preparation and Planning Committee: We’ll meet again on December 14 at 3:00.pm at Coffee Call, 3132 College Dr F, Baton Rouge, LA 70808, UPCOMING BRAS MEETINGS: Light Pollution Committee - HRPO, Wednesday December 4th, 6:15 P.M. -
Density Estimation for Projected Exoplanet Quantities
Density Estimation for Projected Exoplanet Quantities Robert A. Brown Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 [email protected] ABSTRACT Exoplanet searches using radial velocity (RV) and microlensing (ML) produce samples of “projected” mass and orbital radius, respectively. We present a new method for estimating the probability density distribution (density) of the un- projected quantity from such samples. For a sample of n data values, the method involves solving n simultaneous linear equations to determine the weights of delta functions for the raw, unsmoothed density of the unprojected quantity that cause the associated cumulative distribution function (CDF) of the projected quantity to exactly reproduce the empirical CDF of the sample at the locations of the n data values. We smooth the raw density using nonparametric kernel density estimation with a normal kernel of bandwidth σ. We calibrate the dependence of σ on n by Monte Carlo experiments performed on samples drawn from a the- oretical density, in which the integrated square error is minimized. We scale this calibration to the ranges of real RV samples using the Normal Reference Rule. The resolution and amplitude accuracy of the estimated density improve with n. For typical RV and ML samples, we expect the fractional noise at the PDF peak to be approximately 80 n− log 2. For illustrations, we apply the new method to 67 RV values given a similar treatment by Jorissen et al. in 2001, and to the 308 RV values listed at exoplanets.org on 20 October 2010. In addition to an- alyzing observational results, our methods can be used to develop measurement arXiv:1011.3991v3 [astro-ph.IM] 21 Mar 2011 requirements—particularly on the minimum sample size n—for future programs, such as the microlensing survey of Earth-like exoplanets recommended by the Astro 2010 committee. -
A Planetary Mass Companion to the K0 Giant HD 17092
A Planetary Mass Companion to the K0 Giant HD 17092. A. Niedzielski1,2, M. Konacki3, A. Wolszczan2,1, G. Nowak1, G. Maciejewski1, C. R. Gelino5, M. Shao6, M. Shetrone4, L. W. Ramsey2 ABSTRACT We report the discovery of a substellar-mass companion to the K0-giant HD 17092 with the Hobby-Eberly Telescope. In the absence of any correlation of the observed 360-day periodicity with the standard indicators of stellar activity, the observed radial velocity variations are most plausibly explained in terms of a Keplerian motion of a planetary-mass body around the star. With the estimated stellar mass of 2.3M⊙, the minimum mass of the planet is 4.6MJ . The planet’s orbit is characterized by a mild eccentricity of e=0.17 and a semi-major axis of 1.3 AU. This is the tenth published detection of a planetary companion around a red giant star. Such discoveries add to our understanding of planet formation around intermediate-mass stars and they provide dynamical information on the evolution of planetary systems around post-main sequence stars. Subject headings: planetary systems-stars: individual (HD 17092) 1. Introduction After a decade of searches for planets around Sun-like stars, it has become apparent that to achieve a satisfying level of understanding of planet formation and evolution, the surveys have to be extended to other types of stars. So far, the most successful of these have been arXiv:0705.0935v1 [astro-ph] 7 May 2007 1Toru´nCentre for Astronomy, Nicolaus Copernicus University, ul. Gagarina 11, 87-100 Toru´n, Poland 2Department of Astronomy and Astrophysics, Pennsylvania State University, 525 Davey Laboratory, University Park, PA 16802. -
Quantization of Planetary Systems and Its Dependency on Stellar Rotation Jean-Paul A
Quantization of Planetary Systems and its Dependency on Stellar Rotation Jean-Paul A. Zoghbi∗ ABSTRACT With the discovery of now more than 500 exoplanets, we present a statistical analysis of the planetary orbital periods and their relationship to the rotation periods of their parent stars. We test whether the structure of planetary orbits, i.e. planetary angular momentum and orbital periods are ‘quantized’ in integer or half-integer multiples with respect to the parent stars’ rotation period. The Solar System is first shown to exhibit quantized planetary orbits that correlate with the Sun’s rotation period. The analysis is then expanded over 443 exoplanets to statistically validate this quantization and its association with stellar rotation. The results imply that the exoplanetary orbital periods are highly correlated with the parent star’s rotation periods and follow a discrete half-integer relationship with orbital ranks n=0.5, 1.0, 1.5, 2.0, 2.5, etc. The probability of obtaining these results by pure chance is p<0.024. We discuss various mechanisms that could justify this planetary quantization, such as the hybrid gravitational instability models of planet formation, along with possible physical mechanisms such as inner discs magnetospheric truncation, tidal dissipation, and resonance trapping. In conclusion, we statistically demonstrate that a quantized orbital structure should emerge naturally from the formation processes of planetary systems and that this orbital quantization is highly dependent on the parent stars rotation periods. Key words: planetary systems: formation – star: rotation – solar system: formation 1. INTRODUCTION The discovery of now more than 500 exoplanets has provided the opportunity to study the various properties of planetary systems and has considerably advanced our understanding of planetary formation processes. -
Determining the True Mass of Radial-Velocity Exoplanets with Gaia 9 Planet Candidates in the Brown-Dwarf/Stellar Regime and 27 Confirmed Planets
Astronomy & Astrophysics manuscript no. exoplanet_mass_gaia c ESO 2020 September 30, 2020 Determining the true mass of radial-velocity exoplanets with Gaia 9 planet candidates in the brown-dwarf/stellar regime and 27 confirmed planets F. Kiefer1; 2, G. Hébrard1; 3, A. Lecavelier des Etangs1, E. Martioli1; 4, S. Dalal1, and A. Vidal-Madjar1 1 Institut d’Astrophysique de Paris, Sorbonne Université, CNRS, UMR 7095, 98 bis bd Arago, 75014 Paris, France 2 LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Université de Paris, 5 place Jules Janssen, 92195 Meudon, France? 3 Observatoire de Haute-Provence, CNRS, Universiteé d’Aix-Marseille, 04870 Saint-Michel-l’Observatoire, France 4 Laboratório Nacional de Astrofísica, Rua Estados Unidos 154, 37504-364, Itajubá - MG, Brazil Submitted on 2020/08/20 ; Accepted for publication on 2020/09/24 ABSTRACT Mass is one of the most important parameters for determining the true nature of an astronomical object. Yet, many published exoplan- ets lack a measurement of their true mass, in particular those detected thanks to radial velocity (RV) variations of their host star. For those, only the minimum mass, or m sin i, is known, owing to the insensitivity of RVs to the inclination of the detected orbit compared to the plane-of-the-sky. The mass that is given in database is generally that of an assumed edge-on system (∼90◦), but many other inclinations are possible, even extreme values closer to 0◦ (face-on). In such case, the mass of the published object could be strongly underestimated by up to two orders of magnitude. -
Solar System Analogues Among Exoplanetary Systems
Solar System analogues among exoplanetary systems Maria Lomaeva Lund Observatory Lund University ´´ 2016-EXA105 Degree project of 15 higher education credits June 2016 Supervisor: Piero Ranalli Lund Observatory Box 43 SE-221 00 Lund Sweden Populärvetenskaplig sammanfattning Människans intresse för rymden har alltid varit stort. Man har antagit att andra plan- etsystem, om de existerar, ser ut som vårt: med mindre stenplaneter i banor närmast stjärnan och gas- samt isjättar i de yttre banorna. Idag känner man till drygt 2 000 exoplaneter, d.v.s., planeter som kretsar kring andra stjärnor än solen. Man vet även att vissa av dem saknar motsvarighet i solsystemet, t. ex., heta jupitrar (gasjättar som har migrerat inåt och kretsar väldigt nära stjärnan) och superjordar (stenplaneter större än jorden). Därför blir frågan om hur unikt solsystemet är ännu mer intressant, vilket vi försöker ta reda på i det här projektet. Det finns olika sätt att detektera exoplaneter på men två av dem har gett flest resultat: transitmetoden och dopplerspektroskopin. Med transitmetoden mäter man minsknin- gen av en stjärnas ljus när en planet passerar framför den. Den metoden passar bäst för stora planeter med små omloppsbanor. Dopplerspektroskopin använder sig av Doppler effekten som innebär att ljuset utsänt från en stjärna verkar blåare respektive rödare när en stjärna förflyttar sig fram och tillbaka från observatören. Denna rörelse avslöjar att det finns en planet som kretsar kring stjärnan och påverkar den med sin gravita- tion. Dopplerspektroskopin är lämpligast för massiva planeter med små omloppsbanor. Under projektets gång har vi inte bara letat efter solsystemets motsvarigheter utan även studerat planetsystem som är annorlunda. -
Table A1. Planets Discovered by Measuring the Radial Velocities of the Parent Stars Before 17 Oct
Table A1. Planets discovered by measuring the radial velocities of the parent stars before 17 oct. 2017 Minimum detectable projective Upper Lower Minimum Orbital mass of the Orbital Projective error limit error limit Radius projective Duration of Mass of period for planet with period, mass of the of the of the of the (O-C), mass of the Group No. Planet observations, the star, the orbit the orbital days planet, projective projective star, m/s planet number days mʘ at 3R*, period equal mJ mass of the mass of the mʘ detectable days to the planet planet at 3R*, mE duration of observations, mE 1 Kepler-407 c 3000 12,6 6,3 6,3 1,00 1,01 – 2 BD+20 2457 c 621,99 1833 12,47 2,8 49 60,00 123,358 928,4 2282,4 1, 4 3 HD 87646 b 13,481 12,4 0,7 0,7 1,12 1,55 – 4 HIP 67537 b 2557 4419 11,1 0,4 1,1 2,41 8,69 8,0 16,501 57,3 369,2 1, 4 5 HD 220074 b 672,1 1360 11,1 1,8 1,8 1,2 49,7 57,40 192,485 585,5 1123,4 1, 4 6 HD 110014 b 835,5 2950 11,09 1 1 2,17 20,9 45,8 39,306 408,3 1722,5 1, 4 7 HD 1062701 b 2890 1484 11,0? 0,8 0,8 1,32 2,5 8 HD 114762 b 83,915 6901 10,98 0,09 0,09 0,83 1,24 27,40 0,912 36,8 721,6 1, 4 9 TYC 4282-00605-1 b 101,54 1203 10,78 0,12 0,12 0,97 16,2 23,02 40,492 121,2 375,4 1, 4 10 HD 38801 b 696,3 1143 10,7 0,5 0,5 1,36 2,53 6,5 2,077 15,9 130,7 1, 2, 3 11 BD-13 2130 b 714,3 10,6 2,4 – 12 HD 156846 b 359,555 2686 10,57 0,29 0,29 1,35 2,12 6,06 1,599 13,6 161,2 1, 3 13 11 Umi b 516 1287 10,50 2,47 2,47 1,80 24,08 27,5 53,003 239,3 692,9 1, 4 14 HD 219077 b 5501 4850 10,39 0,09 0,09 1,05 1,91 7,63 1,55 14,2 208,2 1, 3 15 18 Del b 993 -
Arxiv:0712.2297V1 [Astro-Ph] 14 Dec 2007 Utemr,Psun Ta.20 Aeue H Paetlac Apparent the Forma Used Planet Have of 2007 Scenarios Al
Exoplanets: Detection, Formation & Dynamics Proceedings IAU Symposium No. 249, 2008 c 2008 International Astronomical Union A.C. Editor, B.D. Editor & C.E. Editor, eds. DOI: 00.0000/X000000000000000X A HET search for planets around evolved stars Andrzej Niedzielski1,2 and Alex Wolszczan2,1 1Toru´nCentre for Astronomy, Nicolaus Copernicus University Gagarina 11,87-100 Toru´n, Poland 2 Dept. of Astronomy & Astrophysics, The Pennsylvania State University, 525 Davey Lab.oratory, University Park, 16802 PA, USA Abstract. We present our ongoing survey of ∼1000 GK-giants with the 9.2-m Hobby-Eberly Telescope in search for planets around evolved stars. The stars selected for this survey are brighter than 11 mag and are located in the section of the HR-diagram, which is approximately delimited by the main sequence, the instability strip, and the coronal dividing line. We use the High Resolution Spectrograph to obtain stellar spectra for radial velocity measurements with −1 a 4-6 m s precision. So far, the survey has discovered a planetary-mass companion to the K0-giant HD 17092, and it has produced a number of plausible planet candidates around other stars. Together with other similar efforts, our program provides information on planet formation around intermediate mass main sequence-progenitors and it will create the experimental basis with which to study dynamics of planetary systems around evolving stars. Keywords. Extrasolar planets, red giants, radial velocity 1. Introduction Precision radial velocity (RV) studies have established more than a decade ago that GK-giant stars exhibit RV variations ranging from days to many hundreds of days (e.g. -
CIRCULAR No. 197 (FEBRUARY 2019)
INTERNATIONAL ASTRONOMICAL UNION COMMISSION G1 (BINARY AND MULTIPLE STAR SYSTEMS) DOUBLE STARS INFORMATION CIRCULAR No. 197 (FEBRUARY 2019) NEW ORBITS ADS Name P T e Ω(2000) 2019 Author(s) α2000δ n a i ! Last ob. 2020 426 BU 1158BC 423y4 1939.8 0.359 169◦8 324◦3 000479 DOCOBO 00310-1005 0◦8503 000897 74◦5 10◦2 2017.6801 325.0 0.491 & LING 622 NOI 3 AaAb 2.835 2006.966 0.019 88.6 267.3 0.017 DOCOBO 00447+4817 126.9841 0.017 113.4 92.9 2007.6326 116.6 0.012 & CAMPO 854 A 2003 82.91 2005.78 0.111 131.7 291.9 0.133 DOCOBO 01023+0552 4.3421 0.193 70.4 64.1 2014.9399 294.8 0.143 & LING - RST 1205AB 289.6 1920.9 0.597 24.9 124.0 0.574 LING 01084-5515 1.2431 1.194 71.2 292.2 2017.6802 125.4 0.578 - HDS 404 25.875 2008.510 0.223 13.4 17.7 0.537 DOCOBO 03095+4544 13.9130 0.519 97.4 172.0 2011.6920 16.3 0.588 & CAMPO 3032 A 469 126.5 1969.9 0.869 61.8 331.0 0.235 DOCOBO 04093-0756 2.8459 0.274 61.7 95.4 2014.8538 331.8 0.236 & LING - B 1122 225.25 2035.97 0.808 88.4 241.9 0.148 DOCOBO 09264-4215 1.5982 0.298 67.7 258.0 2014.0435 243.3 0.146 & CAMPO - COU 284 261.81 2008.85 0.891 11.3 170.3 0.119 DOCOBO 09477+2036 1.3750 0.270 122.2 83.9 2014.2748 168.7 0.125 et al (*) - BU 602 573.8 2144.59 0.824 170.3 127.9 0.533 LING 11468+1500 0.6274 1.030 75.1 85.3 2016.340 128.2 0.534 et al (**) 9511 HU 143Aa,Ab 217.0 2006.70 0.343 139.1 318.6 0.446 LING 15075+5516 1.6590 0.634 74.7 135.8 2016.493 319.4 0.451 et al (**) 1 NEW ORBITS (continuation) ADS Name P T e Ω(2000) 2019 Author(s) α2000δ n a i ! Last ob. -
Red Giants from the Pennsylvania – Toruń Planet Search
EPJ Web of Conferences 16, 02006 (2011) DOI: 10.1051/epjconf/20111602006 C Owned by the authors, published by EDP Sciences, 2011 Red giants from the Pennsylvania – Torun´ Planet Search P. Zielinski´ 1,a, A. Niedzielski1, M. Adamów1 and A. Wolszczan2,3 1Torun´ Centre for Astronomy, Nicolaus Copernicus University, ul. Gagarina 11, 87-100 Torun,´ Poland 2Department for Astronomy and Astrophysics, Pennsylvania State University, 525 Davey Laboratory, University Park, PA 16802, USA 3Center for Exoplanets and Habitable Worlds, Pennsylvania State University, 525 Davey Laboratory, University Park, PA 16802, USA Abstract. The main goal of the Pennsylvania - Torun´ Planet Search (PTPS) is detection and characterization of planets around evolved stars using the high-accuracy radial velocity (RV) technique. The project is performed with the 9.2 m Hobby-Eberly Telescope. To determine stellar parameters and evolutionary status for targets observed within the survey complete spectral analysis of all objects is required. In this paper we present the atmospheric parameters (effective temperatures, surface gravities, microturbulent velocities and metallicities) of a subsample of Red Giant Clump stars using strictly spectroscopic methods based on analysis of equivalent widths of Fe I and Fe II lines. It is shown that our spectroscopic approach brings reliable and consistent results. 1. INTRODUCTION Over 350 extrasolar planets are known today and most of them were discovered by the radial velocity (RV) technique. Apart from many surveys searching for exoplanets around solar-like dwarfs, a few surveys looking for planetary companions orbiting evolved stars exist. For proper interpretation of the results obtained from RV studies of late-type giants detailed knowledge of their physical parameters is required (e.g. -
SAB C SAB 2010 ⋆ ⋆
Boletim ⋆ da ⋆ Boletim da Sociedade Astronˆomica Brasileira, 29, no.1, 26-53 SAB c SAB 2010 ⋆ ⋆ Naming the extrasolar planets W. Lyra American Museum of Natural History, 79th Street at Central Park West, New York, NY, 10024, USA e-mail: [email protected] Received January 14th 2010; accepted August 25th 2010 Resumo. Planetas extrassolares n˜ao s˜ao nomeados e s˜ao referenciados apenas pela sua designa¸c˜ao cient´ıfica. A raz˜ao apresentada pela UAI para n˜ao os nomear ´eque isso seria impratic´avel dado que os planetas devem ser comuns. Apresento algumas raz˜oes sobre porquˆeessa l´ogica ´einsustent´avel, e sugiro nomes para os 429 candidatos a planetas extrassolares conhecidos at´efevereiro de 2010. Os nomes seguem uma associa¸c˜ao com a constela¸c˜ao `aqual a estrela parental pertence e, desta forma, s˜ao em sua maioria retirados da mitologia greco-romana. Outras mitologias podem ser tamb´em usadas desde que uma associa¸c˜ao adequada seja estabelecida. Abstract. Extrasolar planets are not named and are referred to only by their assigned scientific designation. The reason given by the IAU to not name the planets is that it is considered impractical as planets are expected to be common. I advance some reasons as to why this logic is flawed, and suggest names for the 429 extrasolar planet candidates known as of Feb 2010. The names follow a scheme of association with the constellation that the host star pertains to, and therefore are mostly drawn from Roman-Greek mythology. Other mythologies may also be used given that a suitable association is established.