Search Results - "Jeffers, S V"

The evolution of surface magnetic fields in young solar-type stars – I. The first 250 Myr by Folsom, C. P., Petit, P., Bouvier, J., Lèbre, A., Amard, L., Palacios, A., Morin, J., Donati, J.-F., Jeffers, S. V., Marsden, S. C., Vidotto, A. A.

“…The surface rotation rates of young solar-type stars vary rapidly with age from the end of the pre-main sequence through the early main sequence. Important…”
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A BCool magnetic snapshot survey of solar-type stars by Marsden, S. C., Petit, P., Jeffers, S. V., Morin, J., Fares, R., Reiners, A., do Nascimento, J.-D., Aurière, M., Bouvier, J., Carter, B. D., Catala, C., Dintrans, B., Donati, J.-F., Gastine, T., Jardine, M., Konstantinova-Antova, R., Lanoux, J., Lignières, F., Morgenthaler, A., Ramìrez-Vèlez, J. C., Théado, S., Van Grootel, V.

“…We present the results of a major high-resolution spectropolarimetric BCool project magnetic survey of 170 solar-type stars. Surface magnetic fields were…”
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RedDots: a temperate 1.5 Earth-mass planet candidate in a compact multiterrestrial planet system around GJ 1061 by Dreizler, S, Jeffers, S V, Rodríguez, E, Zechmeister, M, Barnes, J R, Haswell, C A, Coleman, G A L, Lalitha, S, Hidalgo Soto, D, Strachan, J B P, Hambsch, F-J, López-González, M J, Morales, N, Rodríguez López, C, Berdiñas, Z M, Ribas, I, Pallé, E, Reiners, A, Anglada-Escudé, G

“…ABSTRACT Small low-mass stars are favourable targets for the detection of rocky habitable planets. In particular, planetary systems in the solar neighbourhood…”
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A multiplanet system of super-Earths orbiting the brightest red dwarf star GJ 887 by Jeffers, S. V., Dreizler, S., Barnes, J. R., Haswell, C. A., Nelson, R. P., Rodríguez, E., López-González, M. J., Morales, N., Luque, R., Zechmeister, M., Vogt, S. S., Jenkins, J. S., Palle, E., Berdi ñas, Z. M., Coleman, G. A. L., Díaz, M. R., Ribas, I., Jones, H. R. A., Butler, R. P., Tinney, C. G., Bailey, J., Carter, B. D., O’Toole, S., Wittenmyer, R. A., Crane, J. D., Feng, F., Shectman, S. A., Teske, J., Reiners, A., Amado, P. J., Anglada-Escudé, G.

“…A nearby multiplanet system Exoplanets can interact gravitationally with other objects orbiting the same star, affecting their evolution and stability…”
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Evolution of brightness and magnetic features of young solar-type stars – I. The young G star HIP 89829 by Perugini, G M, Marsden, S C, Waite, I A, Jeffers, S V, Piskunov, N, Shaw, N, Burton, D M, Mengel, M W, Hughes, J E, Hébrard, E M

“…ABSTRACT The evolution in latitude of sunspots is a key feature of the cyclic solar dynamo. Here, we present the results of a spectroscopic and…”
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The effect of M dwarf starspot activity on low-mass planet detection thresholds by Barnes, J. R., Jeffers, S. V., Jones, H. R. A.

“…In light of the growing interest in searching for low mass, rocky planets, we investigate the impact of starspots on radial velocity searches for earth-mass…”
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Stellar atmospheric parameters of FGK-type stars from high-resolution optical and near-infrared CARMENES spectra by Marfil, E, Tabernero, H M, Montes, D, Caballero, J A, Soto, M G, González Hernández, J I, Kaminski, A, Nagel, E, Jeffers, S V, Reiners, A, Ribas, I, Quirrenbach, A, Amado, P J

“…ABSTRACT With the purpose of assessing classic spectroscopic methods on high-resolution and high signal-to-noise ratio spectra in the near-infrared wavelength…”
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Recovering planet radial velocity signals in the presence of starspot activity in fully convective stars by Barnes, J R, Jeffers, S V, Anglada-Escude, G, Haswell, C A, Jones, H R A, Tuomi, M, Feng, F, Jenkins, J S, Petit, P

“…Accounting for stellar activity is a crucial component of the search for ever-smaller planets orbiting stars of all spectral types. We use Doppler imaging…”
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Magnetic fields and accretion flows on the classical T Tauri star V2129 Oph by Donati, J.-F., Jardine, M. M., Gregory, S. G., Petit, P., Bouvier, J., Dougados, C., Ménard, F., Cameron, A. C., Harries, T. J., Jeffers, S.V., Paletou, F.

“…From observations collected with the ESPaDOnS spectropolarimeter, we report the discovery of magnetic fields at the surface of the mildly accreting classical T…”
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Observations of non-solar-type dynamo processes in stars with shallow convective zones by Jeffers, S. V., Donati, J.-F., Alecian, E., Marsden, S. C.

“…The magnetic field topology and differential rotation are fundamental signatures of the dynamo processes that generate the magnetic activity observed in the…”
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Red Optical Planet Survey: a new search for habitable earths in the southern sky by Barnes, J. R., Jenkins, J. S., Jones, H. R. A., Rojo, P., Arriagada, P., Jordán, A., Minniti, D., Tuomi, M., Jeffers, S. V., Pinfield, D.

“…We present the first results from our Red Optical Planet Survey to search for low-mass planets orbiting late-type dwarfs (M5.5V-M9V) in their habitable zones…”
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J‐band variability of M dwarfs in the WFCAM Transit Survey by Goulding, N. T., Barnes, J. R., Pinfield, D. J., Kovács, G., Birkby, J., Hodgkin, S., Catalán, S., Sipőcz, B., Jones, H. R. A., del Burgo, C., Jeffers, S. V., Nefs, S., Gálvez‐Ortiz, M.‐C., Martin, E. L.

“…ABSTRACT We present an analysis of the photometric variability of M dwarfs in the Wide Field Camera (WFCAM) Transit Survey. Although periodic light‐curve…”
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Spurious ‘active longitudes’ in parametric models of heavily spotted eclipsing binaries by Jeffers, S. V.

“…In this paper, the size distributions of starspots extrapolated from the case of the Sun are modelled on the eclipsing binary SV Cam to synthesize images of…”
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Magnetic activity on AB Doradus: temporal evolution of star-spots and differential rotation from 1988 to 1994 by Jeffers, S. V., Donati, J.-F., Collier Cameron, A.

“…Surface brightness maps for the young K0 dwarf AB Doradus are reconstructed from archival data sets for epochs spanning from 1988 to 1994. By using the…”
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Dynamical and collisional evolution of Halley-type comets by van der Helm, E., Jeffers, S.V.

“…► Catastrophic collisions with planetesimals do not disrupt Halley-type comets. ► Cumulative small collisions with planetesimals do not disrupt Halley-type…”
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Dynamo processes and activity cycles of the active stars AB Doradus, LQ Hydrae and HR 1099 by Donati, J.-F., Cameron, A. Collier, Semel, M., Hussain, G. A. J., Petit, P., Carter, B. D., Marsden, S. C., Mengel, M., Ariste, A. López, Jeffers, S. V., Rees, D. E.

“…In this paper, we present new brightness and magnetic surface images of the young K0 dwarfs AB Doradus and LQ Hydrae, and of the K1 subgiant of the RS CVn…”
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PolarBase: A Database of High-Resolution Spectropolarimetric Stellar Observations by Petit, P., Louge, T., Théado, S., Paletou, F., Manset, N., Morin, J., Marsden, S. C., Jeffers, S. V.

“…PolarBase is an evolving database that contains all stellar data collected with the ESPaDOnS and NARVAL high-resolution spectropolarimeters, in their reduced…”
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The relation between stellar magnetic field geometry and chromospheric activity cycles – II The rapid 120-day magnetic cycle of τ Bootis by Jeffers, S V, Mengel, M, Moutou, C, Marsden, S C, Barnes, J R, Jardine, M M, Petit, P, Schmitt, J H M M, See, V, Vidotto, A A, BCool collaboration

“…One of the aims of the BCool programme is to search for cycles in other stars and to understand how similar they are to the Sun. In this paper, we aim to…”
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The variable magnetic field of V889 Her and the challenge of detecting exoplanets around young Suns using Gaussian process regression by Brown, E L, Marsden, S C, Jeffers, S V, Heitzmann, A, Barnes, J R, Folsom, C P

“…ABSTRACT Discovering exoplanets orbiting young Suns can provide insight into the formation and early evolution of our own solar system, but the extreme…”
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The connection between stellar activity cycles and magnetic field topology by See, V., Jardine, M., Vidotto, A. A., Donati, J.-F., Boro Saikia, S., Bouvier, J., Fares, R., Folsom, C. P., Gregory, S. G., Hussain, G., Jeffers, S. V., Marsden, S. C., Morin, J., Moutou, C., do Nascimento, J. D., Petit, P., Waite, I. A.

“…Zeeman–Doppler imaging (ZDI) has successfully mapped the large-scale magnetic fields of stars over a large range of spectral types, rotation periods and ages…”
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