Results 31 to 40 of about 130,683 (338)

Properties of PSR J1023+0038 Based on Kepler, TESS, and FAST

The Astrophysical Journal, 2023
The pulsar system PSR J1023+0038 is a very interesting binary with radio millisecond pulsar and low-mass X-ray binary transitions, which depend on the stellar accretion process. We have used Kepler light curves with 1 minute cadence and TESS light curves
Li-yun Zhang, Zilu Yang, Baoda Li, Tianhao Su, Prabhakar Misra, Xianming L. Han, Liu Long   +6 more
doaj   +1 more source

DERIVING STELLAR INCLINATION OF SLOW ROTATORS USING STELLAR ACTIVITY [PDF]

The Astrophysical Journal, 2014
18 pages, 7 figures, Accepted for publication in ApJ (this new version includes the 2nd round of the minor referee's comment)
openaire   +2 more sources

Do stellar magnetic cycles influence the measurement of precise radial velocities?

, 2010
The ever increasing level of precision achieved by present and future radial-velocity instruments is opening the way to discovering very low-mass, long-period planets (e.g. solar-system analogs).
Boisse, Bonfils, Bouchy, Brandt, C. Lovis, C. Melo, Cincunegui, Danks, Dravins, Duquennoy, Fernandes, Flower, Golimowski, Halbwachs, Heintz, Huélamo, J. Gomes da Silva, Kürster, Landman, Livingston, Livingston, Lépine, Mayor, Mayor, McMillan, Melo, Meunier, N. C. Santos, Noyes, Paulson, Pepe, Queloz, Queloz, Saar, Saar, Saar, Santos, Santos, Santos, Schaerer, Schaerer, Schaller, Sousa, Tokovinin, Udry, Vaughan, Vaughan, Wright   +47 more
core   +1 more source

Understanding stellar activity-induced radial velocity jitter using simultaneous K2 photometry and HARPS RV measurements [PDF]

, 2017
One of the best ways to improve our understanding of the stellar activity-induced signal in radial velocity (RV) measurements is through simultaneous high-precision photometric and RV observations.
Adibekyan, V., Barros, S. C. C., Boisse, I., Bonfils, X., Cegla, H. M., Deleuil, M., Demangeon, O., Donati, J. -F., Dreizler, S., Dumusque, X., Faria, J. P., Figueira, P., Hébrard, E., Oshagh, M., Pepe, F., Santos, N. C., Udry, S., Watson, C. A.   +17 more
core   +3 more sources

Asteroseismology and Spectropolarimetry of the Exoplanet Host Star λ Serpentis

The Astronomical Journal, 2023
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 rotation period of 25.8 days and surface differential rotation very similar to the Sun.
Travis S. Metcalfe, Derek Buzasi, Daniel Huber, Marc H. Pinsonneault, Jennifer L. van Saders, Thomas R. Ayres, Sarbani Basu, Jeremy J. Drake, Ricky Egeland, Oleg Kochukhov, Pascal Petit, Steven H. Saar, Victor See, Keivan G. Stassun, Yaguang Li, Timothy R. Bedding, Sylvain N. Breton, Adam J. Finley, Rafael A. García, Hans Kjeldsen, Martin B. Nielsen, J. M. Joel Ong, Jakob L. Rørsted, Amalie Stokholm, Mark L. Winther, Catherine A. Clark, Diego Godoy-Rivera, Ilya V. Ilyin, Klaus G. Strassmeier, Sandra V. Jeffers, Stephen C. Marsden, Aline A. Vidotto, Sallie Baliunas, Willie Soon   +33 more
doaj   +1 more source

Polar branches of stellar activity waves: dynamo models and observations

, 2011
[Abridged abstract:] Stellar activity data provide evidence of activity wave branches propagating polewards rather than equatorwards (the solar case). Stellar dynamo theory allows polewards propagating dynamo waves for certain governing parameters.
A. F. Lanza, Baliunas, Baliunas, Barnes, Berdyugina, Brandenburg, Brandenburg, Brandenburg, Brandenburg, Brandenburg, Charbonneau, Choudhuri, Courvoisier, Covas, D. Moss, D. Sokoloff, Dikpati, Dikpati, Dikpati, Donahue, Durney, Granzer, Hall, Holzwarth, Işik, Jeffers, Jouve, Järvinen, Katsova, Kleeorin, Kovári, Käpylä, Lanza, Lanza, Mackay, Makarov, Messina, Moss, Moss, Moss, Moss, Moss, Noyes, Noyes, Oláh, Ossendrijver, Rüdiger, Rüdiger, Rüdiger, Schmitt, Schrijver, Strassmeier, Subramanian, Tobias, Vogt, Wilmot-Smith, Zhang   +56 more
core   +1 more source

Magnetic activity in stellar merger products [PDF]

Monthly Notices of the Royal Astronomical Society, 2007
We study the expected X-ray luminosity of stellar merger products several years after merger. The X-ray emission is assumed to result from magnetic activity. The extended envelope of the merger product possesses a large convective region and it is expected to rotate fast.
Soker, Noam, Tylenda, Romuald
openaire   +2 more sources

TASTE IV. Refining ephemeris and orbital parameters for HAT-P-20b and WASP-1b [PDF]

, 2014
We present four new light curves of transiting exoplanets WASP-1b and HAT-P-20b, observed within the TASTE (The Asiago Search for Transit timing variations of Exoplanets) project.
Bedin, L. R., Borsato, L., Cunial, A., Damasso, M., Granata, V., Malavolta, L., Nascimbeni, V., Piotto, G.   +7 more
core   +1 more source

Filamentary Electron-beam Heating in Solar Flares

The Astrophysical Journal
Radiation-hydrodynamic simulations of the solar-flare chromospheric emission very often lead to an excess of the line intensities when compared to observations.
Michalina Litwicka, Petr Heinzel, Jana Kašparová   +2 more
doaj   +1 more source

STELLAR TRANSITS IN ACTIVE GALACTIC NUCLEI [PDF]

The Astrophysical Journal, 2012
Supermassive black holes (SMBH) are typically surrounded by a dense stellar population in galactic nuclei. Stars crossing the line of site in active galactic nuclei (AGN) produce a characteristic transit lightcurve, just like extrasolar planets do when they transit their host star. We examine the possibility of finding such AGN transits in deep optical,
Béky, Bence, Kocsis, Bence
openaire   +2 more sources