Search Results - "Strassmeier, Klaus G."

The Great Dimming of Betelgeuse: A Surface Mass Ejection and Its Consequences by Dupree, Andrea K., Strassmeier, Klaus G., Calderwood, Thomas, Granzer, Thomas, Weber, Michael, Kravchenko, Kateryna, Matthews, Lynn D., Montargès, Miguel, Tappin, James, Thompson, William T.

“…The bright supergiant, Betelgeuse(Alpha Orionis, HD 39801), underwent a historic optical dimming during 2020 January 27–February 13. Many imaging and…”
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ROTATION PERIODS FOR COOL STARS IN THE 4 Gyr OLD OPEN CLUSTER M67, THE SOLAR-STELLAR CONNECTION, AND THE APPLICABILITY OF GYROCHRONOLOGY TO AT LEAST SOLAR AGE by Barnes, Sydney A., Weingrill, Joerg, Fritzewski, Dario, Strassmeier, Klaus G., Platais, Imants

“…ABSTRACT We report rotation periods for 20 cool (FGK) main sequence member stars of the 4 Gyr-old open cluster M67 (=NGC 2682), obtained by analyzing data from…”
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Spatially Resolved Ultraviolet Spectroscopy of the Great Dimming of Betelgeuse by Dupree, Andrea K., Strassmeier, Klaus G., Matthews, Lynn D., Uitenbroek, Han, Calderwood, Thomas, Granzer, Thomas, Guinan, Edward F., Leike, Reimar, Montargès, Miguel, Richards, Anita M. S., Wasatonic, Richard, Weber, Michael

“…The bright supergiant Betelgeuse (Alpha Orionis, HD 39801) experienced a visual dimming during 2019 December and the first quarter of 2020, reaching an…”
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The Origin of Weakened Magnetic Braking in Old Solar Analogs by Metcalfe, Travis S., Finley, Adam J., Kochukhov, Oleg, See, Victor, Ayres, Thomas R., Stassun, Keivan G., van Saders, Jennifer L., Clark, Catherine A., Godoy-Rivera, Diego, Ilyin, Ilya V., Pinsonneault, Marc H., Strassmeier, Klaus G., Petit, Pascal

“…Abstract The rotation rates of main-sequence stars slow over time as they gradually lose angular momentum to their magnetized stellar winds. The rate of…”
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Nodal Precession and Tidal Evolution of Two Hot Jupiters: WASP-33 b and KELT-9 b by Stephan, Alexander P., Wang, Ji, Cauley, P. Wilson, Gaudi, B. Scott, Ilyin, Ilya, Johnson, Marshall C., Strassmeier, Klaus G.

“…Abstract Hot Jupiters orbiting rapidly rotating stars on inclined orbits undergo tidally induced nodal precession measurable over several years of…”
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Untangling the Sources of Abundance Dispersion in Low-metallicity Stars by Griffith, Emily J., Johnson, Jennifer A., Weinberg, David H., Ilyin, Ilya, Johnson, James W., Rodriguez-Martinez, Romy, Strassmeier, Klaus G.

“…Abstract We measure abundances of 12 elements (Na, Mg, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni) in a sample of 86 metal-poor (−2 ≲ [Fe/H] ≲ −1) subgiant stars in…”
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The PEPSI Exoplanet Transit Survey (PETS). II. A Deep Search for Thermal Inversion Agents in KELT-20 b/MASCARA-2 b with Emission and Transmission Spectroscopy by Johnson, Marshall C., Wang 吉, Ji 王, Asnodkar, Anusha Pai, Bonomo, Aldo S., Gaudi, B. Scott, Henning, Thomas, Ilyin, Ilya, Keles, Engin, Malavolta, Luca, Mallonn, Matthias, Molaverdikhani, Karan, Nascimbeni, Valerio, Patience, Jennifer, Poppenhaeger, Katja, Scandariato, Gaetano, Schlawin, Everett, Shkolnik, Evgenya, Sicilia, Daniela, Sozzetti, Alessandro, Strassmeier, Klaus G., Veillet, Christian, Yan, Fei

“…Abstract Recent observations have shown that the atmospheres of ultrahot Jupiters (UHJs) commonly possess temperature inversions, where the temperature…”
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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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Weakened Magnetic Braking in the Exoplanet Host Star 51 Peg by Metcalfe, Travis S., Strassmeier, Klaus G., Ilyin, Ilya V., Buzasi, Derek, Kochukhov, Oleg, Ayres, Thomas R., Basu, Sarbani, Chontos, Ashley, Finley, Adam J., See, Victor, Stassun, Keivan G., van Saders, Jennifer L., Sepulveda, Aldo G., Ricker, George R.

“…Abstract The consistently low activity level of the old solar analog 51 Peg not only facilitated the discovery of the first hot Jupiter, but also led to the…”
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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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Starspots by Strassmeier, Klaus G.

“…Starspots are created by local magnetic fields on the surfaces of stars, just as sunspots. Their fields are strong enough to suppress the overturning…”
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Space Photometry with Brite-Constellation by Weiss, Werner, Zwintz, Konstanze, Kuschnig, Rainer, Handler, Gerald, Moffat, Anthony, Baade, Dietrich, Bowman, Dominic, Granzer, Thomas, Kallinger, Thomas, Koudelka, Otto, Lovekin, Catherine, Neiner, Coralie, Pablo, Herbert, Pigulski, Andrzej, Popowicz, Adam, Ramiaramanantsoa, Tahina, Rucinski, Slavek, Strassmeier, Klaus, Wade, Gregg

“…BRITE-Constellation is devoted to high-precision optical photometric monitoring of bright stars, distributed all over the Milky Way, in red and/or blue…”
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Letter from the Editor 2022 by Strassmeier, Klaus G.

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On the lithium abundance of the visual binary components ξ Boo A (G8V) and ξ Boo B (K5V) by Strassmeier, Klaus G., Steffen, Matthias

“…A spectroscopic investigation of the lithium resonance doublet in ξ Boo A and ξ Boo B in terms of both abundance and isotopic ratio is presented. We obtained…”
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On the binary orbit of Henry Draper one (HD 1) by Strassmeier, Klaus G., Weber, Michael

“…We present our final orbit for the late‐type spectroscopic binary Henry Draper one (HD 1). area total of 553 spectra from 13 years of observations are used…”
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Comparative study of nearly‐grazing and fully‐grazing exoplanet system parameters derived with TESS and ground‐based instruments by Alexoudi, Xanthippi, Dineva, Ekaterina, Barnes, Sydney, Strassmeier, Klaus G.

“…Grazing transiting systems are rare and difficult to parameterize due to their partial transit geometry. We investigated a sample of 43 nearly‐grazing to…”
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The potassium absorption on HD189733b and HD209458b by Keles, Engin, Mallonn, Matthias, von Essen, Carolina, Carroll, Thorsten A, Alexoudi, Xanthippi, Pino, Lorenzo, Ilyin, Ilya, Poppenhäger, Katja, Kitzmann, Daniel, Nascimbeni, Valerio, Turner, Jake D, Strassmeier, Klaus G

“…ABSTRACT In this work, we investigate the potassium excess absorption around 7699 Å of the exoplanets HD189733b and HD209458b. For this purpose, we used…”
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The PEPSI exoplanet transit survey (PETS) I: investigating the presence of a silicate atmosphere on the super-earth 55 Cnc e by Keles, Engin, Mallonn, Matthias, Kitzmann, Daniel, Poppenhaeger, Katja, Hoeijmakers, H Jens, Ilyin, Ilya, Alexoudi, Xanthippi, Carroll, Thorsten A, Alvarado-Gomez, Julian, Ketzer, Laura, Bonomo, Aldo S, Borsa, Francesco, Gaudi, B Scott, Henning, Thomas, Malavolta, Luca, Molaverdikhani, Karan, Nascimbeni, Valerio, Patience, Jennifer, Pino, Lorenzo, Scandariato, Gaetano, Schlawin, Everett, Shkolnik, Evgenya, Sicilia, Daniela, Sozzetti, Alessandro, Foster, Mary G, Veillet, Christian, Wang, Ji, Yan, Fei, Strassmeier, Klaus G

“…ABSTRACT The study of exoplanets and especially their atmospheres can reveal key insights on their evolution by identifying specific atmospheric species. For…”
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Characterization of chromospheric activity based on Sun‐as‐a‐star spectral and disk‐resolved activity indices by Dineva, Ekaterina, Pearson, Jeniveve, Ilyin, Ilya, Verma, Meetu, Diercke, Andrea, Strassmeier, Klaus G., Denker, Carsten

“…The strong chromospheric absorption lines Ca ii H & K are tightly connected to stellar surface magnetic fields. Only for the Sun, spectral activity indices can…”
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Contemporaneous Imaging Comparisons of the Spotted Giant σ Geminorum Using Interferometric, Spectroscopic, and Photometric Data by Roettenbacher, Rachael M., Monnier, John D., Korhonen, Heidi, Harmon, Robert O., Baron, Fabien, Hackman, Thomas, Henry, Gregory W., Schaefer, Gail H., Strassmeier, Klaus G., Weber, Michael, Brummelaar, Theo A. ten

“…Abstract Nearby active stars with relatively rapid rotation and large starspot structures offer the opportunity to compare interferometric, spectroscopic, and…”
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