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Neo-Narval Science Case REF.: NEONARVAL-XXX-OMP-NT-XXXX ISSUE : V1.4 DAT E : 23/02/2014 PAGE : 1/ 28 TITLE: Neo-Narval Science Case REF.: NEONARVAL-XXX-OMP-NT-XXXX ISSUE : V1.4 DAT E : 23/02/2014 PAGE : 1/ 28 Neo- Narval Science Case Prepared by Signature Name: Torsten BÖHM, Rémi CABANAC Institute: OMP/TBL/IRAP Date: 11/02/2014 Accepted by Signature Name: Torsten BOEHM Institute: OMP/IRAP Date: Approved and Application authorized by Signature Name: Institute: OMP Date: NEONARVAL-XXX-OMP-NT-XXXX_ Neo-Narval Science Case TITLE: Neo-Narval Science Case REF.: NEONARVAL-XXX-OMP-NT-XXXX ISSUE : V1.4 DAT E : 23/02/2014 PAGE : 2/ 28 Summary: This document describe the Science Case of Neo-Narval Keywords: spectropolarimetry, velocimetry, stellar evolution, exoplanets DISTRIBUTION LIST Publicly released 22/02/2014 V1.0 06/03/2014 V1.2 DOCUMENT CHANGE RECORD Issue Revision Date Modified Reason for change / Observations pages 1.1 23/02/2014 comments C. Baruteau taken into account 1.2 06/03/2014 Sect. 2.3.2 included inspiral time calculation. 1.3 07/03/2014 Sect. 2.3 implementing CS TBL members F Martins and C Moutou comments NEONARVAL-XXX-OMP-NT-XXXX_ Neo-Narval Science Case TITLE: Neo-Narval Science Case REF.: NEONARVAL-XXX-OMP-NT-XXXX ISSUE : V1.4 DAT E : 23/02/2014 PAGE : 3/ 28 Table of Contents EXECUTIVE SUMMARY........................................................................................................................................... 5 1. MAGNETIC FIELD STUDIES AT PIC DU MIDI IN THE PAST AND TODAY ................................................ 6 2. THE NEO-NARVAL SCIENCE CASE .................................................................................................................. 7 2.1. A SHORT OVERVIEW OF EXOPLANET SEARCH IN 2014 ............................................................................................ 9 2.2. NEO-NARVAL: UNDERSTANDING MAGNETIC ACTIVITY JITTER .............................................................................. 10 2.2.1. mechanisms that can produce RV jitter ............................................................................................................................ 10 2.2.2. Observed RV jitter amplitudes .......................................................................................................................................... 10 2.2.3. Neo-Narval: a magnetic jitter probe ................................................................................................................................. 12 2.3. EXOPLANETS AROUND EVOLVED STARS .............................................................................................................. 13 2.3.1. The observations of planets around evolved stars ............................................................................................................ 13 2.3.2. Planet engulfment ............................................................................................................................................................. 14 2.3.3. What can Neo-Narval bring to the observations of exoplanets around evolved stars?................................................... 15 2.3.4. potential evolved Star targets for Neo-Narval .................................................................................................................. 16 2.4. SPECTROPOLARIMETRY WITH NARVAL - ONGOING PROJECTS .............................................................................. 17 2.4.1. Narval: 7 years of seminal works ..................................................................................................................................... 17 2.4.2. Magnetic fields and stellar evolution................................................................................................................................ 17 2.4.3. Stellar Dynamos ................................................................................................................................................................ 18 2.4.4. Origin and impact of magnetic fields in massive and intermediate-mass stars .............................................................. 19 2.5. NEO-NARVAL CONTRIBUTION TO SPACE MISSIONS ............................................................................................... 22 3. SCIENCE AND TECHNICAL SPECIFICATIONS ............................................................................................ 23 4. INSTRUMENTAL CONCEPTS ........................................................................................................................... 24 4.1. THE NARVAL SPECTROPOLARIMETER, CURRENT STATUS ..................................................................................... 24 4.2. NEO-NARVAL: A RADIAL-VELOCITY STABILISED SPECTROPOLARIMETER .............................................................. 24 4.3. NECESSARY SERVICE OPERATIONS ...................................................................................................................... 25 5. TBL ROADMAP, NEO-NARVAL ORGANISATION, BUDGET AND CALENDAR........................................ 26 5.1. TBL ROADMAP .................................................................................................................................................. 26 5.2. NEO-NARVAL ORGANISATION ............................................................................................................................ 27 5.3. NEO-NARVAL BUDGET ....................................................................................................................................... 28 5.4. NEO-NARVAL CALENDAR .................................................................................................................................. 28 NEONARVAL-XXX-OMP-NT-XXXX_ Neo-Narval Science Case TITLE: Neo-Narval Science Case REF.: NEONARVAL-XXX-OMP-NT-XXXX ISSUE : V1.4 DAT E : 23/02/2014 PAGE : 4/ 28 GENERAL ASPECTS This document presents the science case of Neo-Narval, and the primary science requirements. Applicable documents N° Document Title Document Number Issue / Date Reference documents N° Document Title Document Number Issue / Date Acronyms AIT Assemblage Intégration Test CFHT Canada-France-Hawaii Telescope CPER Contrat Plan Etat Région ESPaDOnS Echelle SpectroPolarimeter Device for the Observation of Stars (twin of Narval at CFHT) ETSRC European Telescopes Strategic Review Committee IRAP Institut de Recherche en Astrophysique et Planétologie MS Main Sequence (of the stellar evolution) P LAT O PLAnet Transit Observatory OSU Observatoire des sciences de l'Univers RGB Red Giant Branch (of the stellar evolution) RV Radial velocity SPIP SPIROU @ Pic du midi TBL Telescope Bernard Lyot TESS Transiting Exoplanet Survey Satellite TTV Transit Timing Variation UMS Unité Mixte de Service UPS University of Toulouse Paul Sabatier NEONARVAL-XXX-OMP-NT-XXXX_ Neo-Narval Science Case TITLE: Neo-Narval Science Case REF.: NEONARVAL-XXX-OMP-NT-XXXX ISSUE : V1.4 DAT E : 23/02/2014 PAGE : 5/ 28 EXECUTIVE SUMMARY The Telescope Bernard Lyot at Pic du Midi (France) is dedicated since almost two decades to the analysis of stellar magnetic fields by the aim of high resolution spectropolarimetry. Since 2007, and together with its sister- instrument Espadons at CFHT, Narval played and still plays a major role in this challenging research domain. With the rise of exoplanet search in recent years, a promising evolution of the instrument towards a highly radial-velocity stabilised spectropolarimeter is now required. We call this instrumental evolution Neo-Narval. More precisely, the quest for exoplanets around the magnetically active lower and intermediate mass stars (later than F0) is strongly limited due to the so-called magnetic jitter. Active bright or dark plages on the surface of the stars are linked to magnetic activity and corotate with the star's rotation period. Their signature in radial velocity can exceed by far the signature of an exoplanet, and, if close to its expected orbital period a confusion between both can occur. The simultaneous determination of magnetic structures on the surface of the star, and the subsequent deduction of the induced jitter linked to associated active plages will eventually allow to search for and unambiguously confirm new exoplanet detections, despite a highly "polluted" radial velocity signal. Moreover, the search for exoplanets around lower mass G to M dwarfs, but also more evolved giant stars surrounded by exoplanetary systems in final stages, will be strongly improved thanks to a stabilised instrument with a spectral range extending up to 1 micron. In addition, the classical spectropolarimetric studies of the magnetism throughout the HR diagram (a core task of Narval) can be efficiently pursued with the optimised instrument. To address these scientific goals a radial velocity long-term stability of better than 3m/s is needed. Different design concepts are under discussion, involving a pressurised vessel (ambient pressure, nitrogen filled), englobing either the entire spectrograph or solely the dispersive and refractive parts of it. The pressure should be stable within a 10microbar level in order to ensure the required stability of the refraction index of the gas. To achieve that, an actively thermalised (∆T ± 0.01K) outer enclosure will be required. In order to ensure a stable light injection in the spectrograph, the addition of octagonal fibre segments is foreseen. In parallel to the major upgrade of the Narval instrument, a thorough maintenance project (concerning the camera and mechanical aspects of the polarimetric device) is required, which is part
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