Search Results - "Jeffers, Sandra V."

Do Non-dipolar Magnetic Fields Contribute to Spin-down Torques? by See, Victor, Matt, Sean P., Finley, Adam J., Folsom, Colin P., Saikia, Sudeshna Boro, Donati, Jean-Francois, Fares, Rim, Hébrard, Élodie M., Jardine, Moira M., Jeffers, Sandra V., Marsden, Stephen C., Mengel, Matthew W., Morin, Julien, Petit, Pascal, Vidotto, Aline A., Waite, Ian A.

“…Main-sequence low-mass stars are known to spin down as a consequence of their magnetized stellar winds. However, estimating the precise rate of this spin-down…”
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Multiwavelength Campaign Observations of a Young Solar-type Star, EK Draconis. I. Discovery of Prominence Eruptions Associated with Superflares by Namekata, Kosuke, Airapetian, Vladimir S., Petit, Pascal, Maehara, Hiroyuki, Ikuta, Kai, Inoue, Shun, Notsu, Yuta, Paudel, Rishi R., Arzoumanian, Zaven, Avramova-Boncheva, Antoaneta A., Gendreau, Keith, Jeffers, Sandra V., Marsden, Stephen, Morin, Julien, Neiner, Coralie, Vidotto, Aline A., Shibata, Kazunari

“…Abstract Young solar-type stars frequently produce superflares, serving as a unique window into the young Sun-Earth environments. Large solar flares are…”
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Estimating Magnetic Filling Factors from Zeeman-Doppler Magnetograms by See, Victor, Matt, Sean P., Folsom, Colin P., Saikia, Sudeshna Boro, Donati, Jean-Francois, Fares, Rim, Finley, Adam J., Hébrard, Élodie M., Jardine, Moira M., Jeffers, Sandra V., Lehmann, Lisa T., Marsden, Stephen C., Mengel, Matthew W., Morin, Julien, Petit, Pascal, Vidotto, Aline A., Waite, Ian A.

“…Low-mass stars are known to have magnetic fields that are believed to be of dynamo origin. Two complementary techniques are principally used to characterize…”
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Constraints on Magnetic Braking from the G8 Dwarf Stars 61 UMa and τ Cet by Metcalfe, Travis S., Strassmeier, Klaus G., Ilyin, Ilya V., van Saders, Jennifer L., Ayres, Thomas R., Finley, Adam J., Kochukhov, Oleg, Petit, Pascal, See, Victor, Stassun, Keivan G., Jeffers, Sandra V., Marsden, Stephen C., Morin, Julien, Vidotto, Aline A.

“…Abstract During the first half of their main-sequence lifetimes, stars rapidly lose angular momentum to their magnetized winds, a process known as magnetic…”
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Modeling the Chromosphere and Transition Region of Planet-hosting Star GJ 436 by Hintz, Dominik, Peacock, Sarah, Barman, Travis, Fuhrmeister, Birgit, Nagel, Evangelos, Schweitzer, Andreas, Jeffers, Sandra V., Ribas, Ignasi, Reiners, Ansgar, Quirrenbach, Andreas, Amado, Pedro J., Béjar, Victor J. S., Caballero, José A., Hatzes, Artie P., Montes, David

“…Abstract Ahead of upcoming space missions intending to conduct observations of low-mass stars in the ultraviolet (UV) spectral region it becomes imperative to…”
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Stellar Activity Cycles by Jeffers, Sandra V., Kiefer, René, Metcalfe, Travis S.

“…The magnetic field of the Sun is generated by internal dynamo process with a cyclic period of 11 years or a 22 year magnetic cycle. The signatures of the Sun’s…”
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A terrestrial planet candidate in a temperate orbit around Proxima Centauri by Anglada-Escudé, Guillem, Amado, Pedro J., Barnes, John, Berdiñas, Zaira M., Butler, R. Paul, Coleman, Gavin A. L., de la Cueva, Ignacio, Dreizler, Stefan, Endl, Michael, Giesers, Benjamin, Jeffers, Sandra V., Jenkins, James S., Jones, Hugh R. A., Kiraga, Marcin, Kürster, Martin, López-González, Marίa J., Marvin, Christopher J., Morales, Nicolás, Morin, Julien, Nelson, Richard P., Ortiz, José L., Ofir, Aviv, Paardekooper, Sijme-Jan, Reiners, Ansgar, Rodríguez, Eloy, Rodrίguez-López, Cristina, Sarmiento, Luis F., Strachan, John P., Tsapras, Yiannis, Tuomi, Mikko, Zechmeister, Mathias

“…A small planet of at least 1.3 Earth masses is orbiting Proxima Centauri with a period of about 11.2 days, with the potential for liquid water on its surface…”
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Coronal Mass Ejections and Type II Radio Emission Variability during a Magnetic Cycle on the Solar-type Star ϵ Eridani by Ó Fionnagáin, Dúalta, Kavanagh, Robert D., Vidotto, Aline A., Jeffers, Sandra V., Petit, Pascal, Marsden, Stephen, Morin, Julien, Golden, Aaron

“…Abstract We simulate possible stellar coronal mass ejection (CME) scenarios over the magnetic cycle of ϵ Eridani (18 Eridani; HD 22049). We use three separate…”
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The rotationally modulated polarization of ξ Boo A by Cotton, Daniel V, Evensberget, Dag, Marsden, Stephen C, Bailey, Jeremy, Zhao, Jinglin, Kedziora-Chudczer, Lucyna, Carter, Bradley D, Bott, Kimberly, Vidotto, Aline A, Petit, Pascal, Morin, Julien, Jeffers, Sandra V

“…We have observed the active starξBoo A (HD 131156A) with high precision broadbandlinear polarimetry contemporaneously with circular spectropolarimetry. We find…”
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MAGNETICALLY CONTROLLED ACCRETION ON THE CLASSICAL T TAURI STARS GQ LUPI AND TW HYDRAE by Johns-Krull, Christopher M, Chen, Wei, Valenti, Jeff A, Jeffers, Sandra V, Piskunov, Nikolai E, Kochukhov, Oleg, MAKAGANIUK, V, Stempels, H C, SNIK, FRANS, Keller, Christoph, Rodenhuis, M

“…We present high spectral resolution (R [approximate] 108,000) Stokes V polarimetry of the classical T Tauri stars (CTTSs) GQ Lup and TW Hya obtained with the…”
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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 Transiting, Temperate Mini-Neptune Orbiting the M Dwarf TOI-1759 Unveiled by TESS by Espinoza, Néstor, Pallé, Enric, Kemmer, Jonas, Luque, Rafael, Caballero, José A., Cifuentes, Carlos, Herrero, Enrique, Sánchez Béjar, Víctor J., Stock, Stephan, Molaverdikhani, Karan, Morello, Giuseppe, Kossakowski, Diana, Schlecker, Martin, Amado, Pedro J., Bluhm, Paz, Cortés-Contreras, Miriam, Henning, Thomas, Kreidberg, Laura, Kürster, Martin, Lafarga, Marina, Lodieu, Nicolas, Morales, Juan Carlos, Oshagh, Mahmoudreza, Passegger, Vera M., Pavlov, Alexey, Quirrenbach, Andreas, Reffert, Sabine, Reiners, Ansgar, Ribas, Ignasi, Rodríguez, Eloy, López, Cristina Rodríguez, Schweitzer, Andreas, Trifonov, Trifon, Chaturvedi, Priyanka, Dreizler, Stefan, Jeffers, Sandra V., Kaminski, Adrian, López-González, María José, Lillo-Box, Jorge, Montes, David, Nowak, Grzegorz, Pedraz, Santos, Vanaverbeke, Siegfried, Zapatero Osorio, Maria R., Zechmeister, Mathias, Collins, Karen A., Girardin, Eric, Guerra, Pere, Naves, Ramon, Crossfield, Ian J. M., Matthews, Elisabeth C., Howell, Steve B., Ciardi, David R., Gonzales, Erica, Matson, Rachel A., Beichman, Charles A., Schlieder, Joshua E., Barclay, Thomas, Vezie, Michael, Villaseñor, Jesus Noel, Daylan, Tansu, Mireies, Ismael, Dragomir, Diana, Twicken, Joseph D., Jenkins, Jon, Winn, Joshua N., Latham, David, Ricker, George, Seager, Sara

“…Abstract We report the discovery and characterization of TOI-1759 b, a temperate (400 K) sub-Neptune-sized exoplanet orbiting the M dwarf TOI-1759 (TIC…”
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The open flux evolution of a solar-mass star on the main sequence by See, V., Jardine, M., Vidotto, A. A., Donati, J.-F., Boro Saikia, S., Fares, R., Folsom, C. P., Jeffers, S. V., Marsden, S. C., Morin, J., Petit, P.

“…Abstract Magnetic activity is known to be correlated to the rotation period for moderately active main-sequence solar-like stars. In turn, the stellar rotation…”
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Asteroseismology and Spectropolarimetry of the Exoplanet Host Star λ Serpentis by Metcalfe, Travis S., Buzasi, Derek, Huber, Daniel, Pinsonneault, Marc H., van Saders, Jennifer L., Ayres, Thomas R., Basu, Sarbani, Drake, Jeremy J., Egeland, Ricky, Kochukhov, Oleg, Petit, Pascal, Saar, Steven H., See, Victor, Stassun, Keivan G., Li, Yaguang, Bedding, Timothy R., Breton, Sylvain N., Finley, Adam J., García, Rafael A., Kjeldsen, Hans, Nielsen, Martin B., Ong, J. M. Joel, Rørsted, Jakob L., Stokholm, Amalie, Winther, Mark L., Clark, Catherine A., Godoy-Rivera, Diego, Ilyin, Ilya V., Strassmeier, Klaus G., Jeffers, Sandra V., Marsden, Stephen C., Vidotto, Aline A., Baliunas, Sallie, Soon, Willie

“…Abstract The bright star λ Ser hosts a hot Neptune with a minimum mass of 13.6 M ⊕ and a 15.5 day orbit. It also appears to be a solar analog, with a mean…”
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Two planets around Kapteyn's star: a cold and a temperate super-Earth orbiting the nearest halo red dwarf by Anglada-Escudé, G., Arriagada, P., Tuomi, M., Zechmeister, M., Jenkins, J. S., Ofir, A., Dreizler, S., Gerlach, E., Marvin, C. J., Reiners, A., Jeffers, S. V., Butler, R. P., Vogt, S. S., Amado, P. J., Rodríguez-López, C., Berdiñas, Z. M., Morin, J., Crane, J. D., Shectman, S. A., Thompson, I. B., Díaz, M., Rivera, E., Sarmiento, L. F., Jones, H. R. A.

“…Exoplanets of a few Earth masses can be now detected around nearby low-mass stars using Doppler spectroscopy. In this Letter, we investigate the radial…”
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Slingshot prominences: coronal structure, mass loss and spin down by See, Victor, Matt, Sean, Finley, Adam, Folsom, Colin P., Saikia, Sudeshna Boro, Donati, Jean-François, Fares, Rim, Hebrard, Élodie M., Jeffers, Sandra V., Marsden, Stephen, Mengel, Matthew, Morin, Julien, Petit, Pascal, Vidotto, Aline, Waite, Ian, Jardine, Moira, Cameron, a Collier, Donati, J-F, Hussain, G

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NO EVIDENCE FOR ACTIVITY CORRELATIONS IN THE RADIAL VELOCITIES OF KAPTEYN'S STAR by Anglada-Escudé, G., Tuomi, M., Arriagada, P., Zechmeister, M., Jenkins, J. S., Ofir, A., Dreizler, S., Gerlach, E., Marvin, C. J., Reiners, A., Jeffers, S. V., Butler, R. Paul, Vogt, S. S., Amado, P. J., Rodríguez-López, C., Berdiñas, Z. M., Morin, J., Crane, J. D., Shectman, S. A., Díaz, M. R., Sarmiento, L. F., Jones, H. R. A.

“…ABSTRACT Stellar activity may induce Doppler variability at the level of a few m s−1 which can then be confused by the Doppler signal of an exoplanet orbiting…”
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ɛ Eridani: an active K dwarf and a planet hosting star?. The variability of its large-scale magnetic field topology by Jeffers, Sandra V., Petit, Pascal, Marsden, Stephen C., Morin, Julien, Donati, Jean-François, Folsom, Colin P.

“…The young K-dwarf ɛ Eridani is an example of a young active planet hosting star that has shown over long-term monitoring of its chromospheric emission to…”
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Stellar Activity Cycles by Jeffers, Sandra V, Kiefer, Rene, Metcalfe, Travis S

“…The magnetic field of the Sun is generated by internal dynamo process with a cyclic period of 11 years or a 22 year magnetic cycle. The signatures of the Sun's…”
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Multiwavelength Campaign Observations of a Young Solar-type Star, EK Draconis. I. Discovery of Prominence Eruptions Associated with Superflares by Namekata, Kosuke, Airapetian, Vladimir S, Petit, Pascal, Maehara, Hiroyuki, Ikuta, Kai, Inoue, Shun, Notsu, Yuta, Paudel, Rishi R, Arzoumanian, Zaven, Avramova-Boncheva, Antoaneta A, Gendreau, Keith, Jeffers, Sandra V, Marsden, Stephen, Morin, Julien, Neiner, Coralie, Vidotto, Aline A, Shibata, Kazunari

“…Young solar-type stars frequently produce superflares, serving as a unique window into the young Sun-Earth environments. Large solar flares are closely linked…”
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