dc.contributor.author | Barnes, J. R. | |
dc.contributor.author | Jenkins, J. S. | |
dc.contributor.author | Jones, H. R A | |
dc.contributor.author | Jeffers, S. V. | |
dc.contributor.author | Rojo, P. | |
dc.contributor.author | Arriagada, P. | |
dc.contributor.author | Jordán, A. | |
dc.contributor.author | Minniti, D. | |
dc.contributor.author | Tuomi, Mikko | |
dc.contributor.author | Pinfield, David | |
dc.contributor.author | Anglada-Escudé, G. | |
dc.date.accessioned | 2017-03-09T17:41:23Z | |
dc.date.available | 2017-03-09T17:41:23Z | |
dc.date.issued | 2014-04-11 | |
dc.identifier.citation | Barnes , J R , Jenkins , J S , Jones , H R A , Jeffers , S V , Rojo , P , Arriagada , P , Jordán , A , Minniti , D , Tuomi , M , Pinfield , D & Anglada-Escudé , G 2014 , ' Precision radial velocities of 15 M5-M9 dwarfs ' , Monthly Notices of the Royal Astronomical Society , vol. 439 , no. 3 , pp. 3094-3113 . https://doi.org/10.1093/mnras/stu172 | |
dc.identifier.issn | 0035-8711 | |
dc.identifier.uri | http://hdl.handle.net/2299/17697 | |
dc.description | J. R. Barnes, 'Precision radial velocities of 15 M5-M9 dwarfs', Monthly Notices of the Royal Astronomical Society, Vol. 439 (3): 3094 - 3113, first published online 20 February 2014. The version of record is available online at doi: 10.1093/mnras/stu172 © 2014 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. | |
dc.description.abstract | We present radial velocity measurements of a sample ofM5V-M9Vstars from our Red-Optical Planet Survey, operating at 0.652-1.025 μm. Radial velocities for 15 stars, with rms precision down to 2.5m-1 over a week-long time-scale, are achieved using thorium-argon reference spectra. We are sensitive to planets with mp sin i ≥ 1.5M⊕ (3M⊕ at 2σ) in the classical habitable zone, and our observations currently rule out planets with mp sini ≥ 0.5MJ at 0.03 au for all our targets. A total of 9 of the 15 targets exhibit rms<16m-1, which enables us to rule out the presence of planets with mp sini > 10M⊕ in 0.03 au orbits. Since the mean rotation velocity is of the order of 8 km-1 for an M6V star and 15 km -1 for M9V, we avoid observing only slow rotators that would introduce a bias towards low axial inclination (i< 90°) systems, which are unfavourable for planet detection. Our targets with the highest v sin i values exhibit radial velocities significantly above the photon-noise-limited precision, even after accounting for v sin i. We have therefore monitored stellar activity via chromospheric emission from the Hα and Ca II infrared triplet lines. A clear trend of log10(LHα/Lbol) with radial velocity rms is seen, implying that significant starspot activity is responsible for the observed radial velocity precision floor. The implication that most late M dwarfs are significantly spotted, and hence exhibit time varying line distortions, indicates that observations to detect orbiting planets need strategies to reliablymitigate against the effects of activity-induced radial velocity variations. | en |
dc.format.extent | 20 | |
dc.format.extent | 2000079 | |
dc.language.iso | eng | |
dc.relation.ispartof | Monthly Notices of the Royal Astronomical Society | |
dc.subject | Planetary systems | |
dc.subject | Planets and satellites: detection | |
dc.subject | Stars: activity | |
dc.subject | Stars: atmospheres | |
dc.subject | Stars: low-Mass | |
dc.subject | Techniques: radial velocities | |
dc.subject | Astronomy and Astrophysics | |
dc.subject | Space and Planetary Science | |
dc.title | Precision radial velocities of 15 M5-M9 dwarfs | en |
dc.contributor.institution | Centre for Astrophysics Research | |
dc.contributor.institution | School of Physics, Astronomy and Mathematics | |
dc.contributor.institution | Science & Technology Research Institute | |
dc.description.status | Peer reviewed | |
dc.identifier.url | http://www.scopus.com/inward/record.url?scp=84896471807&partnerID=8YFLogxK | |
rioxxterms.versionofrecord | 10.1093/mnras/stu172 | |
rioxxterms.type | Journal Article/Review | |
herts.preservation.rarelyaccessed | true | |