Search Results - "GÜDEL, Manuel"

The Sun Through Time by Güdel, Manuel

“…Magnetic activity of stars like the Sun evolves in time because of spin-down owing to angular momentum removal by a magnetized stellar wind. These magnetic…”
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The young Sun's XUV-activity as a constraint for lower CO2-limits in the Earth's Archean atmosphere by Johnstone, Colin P., Lammer, Helmut, Kislyakova, Kristina G., Scherf, Manuel, Güdel, Manuel

“…•Earth Archean upper atmosphere studied using state-of-the-art models.•High atmospheric CO2 levels and low solar activity needed to prevent rapid escape to…”
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X-Ray Irradiation of the Giant Planet Orbiting the T Tauri Star TAP 26 by Skinner, Stephen L., Güdel, Manuel

“…We present new Chandra X-ray observations of TAP 26, a ≈17 Myr old magnetically active weak-lined T Tauri star that has been reported to host a massive planet…”
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Self-organized Criticality in Stellar Flares by Aschwanden, Markus J., Güdel, Manuel

“…Power-law size distributions are the hallmarks of nonlinear energy dissipation processes governed by self-organized criticality (SOC). Here we analyze 75 data…”
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Physical Processes in Magnetically Driven Flares on the Sun, Stars, and Young Stellar Objects by Benz, Arnold O., Güdel, Manuel

“…The first flare on the Sun was observed exactly 150 years ago. During most of the long history, only secondary effects have been noticed, so flares remained a…”
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Evolution of the Solar Activity over Time and Effects on Planetary Atmospheres. I. High-Energy Irradiances (1-1700 Å) by Ribas, Ignasi, Guinan, Edward F, Güdel, Manuel, Audard, Marc

“…We report on the results of the Sun in Time multiwavelength program (X-rays to UV) of solar analogs with ages covering 60.1-7 Gyr. The chief science goals are…”
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Origin and evolution of the atmospheres of early Venus, Earth and Mars by Lammer, Helmut, Zerkle, Aubrey L., Gebauer, Stefanie, Tosi, Nicola, Noack, Lena, Scherf, Manuel, Pilat-Lohinger, Elke, Güdel, Manuel, Grenfell, John Lee, Godolt, Mareike, Nikolaou, Athanasia

“…We review the origin and evolution of the atmospheres of Earth, Venus and Mars from the time when their accreting bodies were released from the protoplanetary…”
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Million-Degree Plasma Pervading the Extended Orion Nebula by Güdel, Manuel, Briggs, Kevin R., Montmerle, Thierry, Audard, Marc, Rebull, Luisa, Skinner, Stephen L.

“…Most stars form as members of large associations within dense, very cold (10 to 100 kelvin) molecular clouds. The nearby giant molecular cloud in Orion hosts…”
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Episodic excursions of low-mass protostars on the Hertzsprung–Russell diagram by Elbakyan, Vardan G, Vorobyov, Eduard I, Rab, Christian, Meyer, Dominique M-A, Güdel, Manuel, Hosokawa, Takashi, Yorke, Harold

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The Mid-Infrared Instrument for the James Webb Space Telescope, I: Introduction by Rieke, G. H., Wright, G. S., Böker, T., Bouwman, J., Colina, L., Glasse, Alistair, Gordon, K. D., Greene, T. P., Güdel, Manuel, Henning, Th, Justtanont, K., Lagage, P.-O., Meixner, M. E., Nørgaard-Nielsen, H.-U., Ray, T. P., Ressler, M. E., van Dishoeck, E. F., Waelkens, C.

“…MIRI (the Mid-Infrared Instrument for the James Webb Space Telescope [JWST]) operates from 5 to 28.5 μm and combines over this range: (1) unprecedented…”
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FIRST DETECTION OF THERMAL RADIO EMISSION FROM SOLAR-TYPE STARS WITH THE KARL G. JANSKY VERY LARGE ARRAY by Villadsen, Jackie, Hallinan, Gregg, Bourke, Stephen, Gudel, Manuel, RUPEN, MICHAEL

“…We present the first detections of thermal radio emission from the atmospheres of solar-type stars [tau] Cet, [eta] Cas A, and 40 Eri A. These stars all…”
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The Sun in Time: Activity and Environment by Güdel, Manuel

“…The Sun’s magnetic activity has steadily declined during its main-sequence life. While the solar photospheric luminosity was about 30% lower 4.6 Gyr ago when…”
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X-Ray Observations of the Enigmatic Wolf–Rayet System θ Mus: Two’s Company but Three’s a Crowd by Skinner, Stephen L., Zhekov, Svetozar A., Güdel, Manuel, Schmutz, Werner

“…θ Mus is a remarkable spectroscopic binary (SB) consisting of a carbon-type Wolf–Rayet star and OV companion (WC6+O6–7V) in a ≈19 days orbit. In addition an…”
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Chandra Observations of the Massive Star-forming Region Onsala 2 by Skinner, Stephen L., Sokal, Kimberly R., Güdel, Manuel

“…Previous radio and infrared observations have revealed an obscured region of high-mass star formation in Cygnus known as Onsala 2 (ON2). Within this region…”
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Investigating the structure of star-forming regions using INDICATE by Blaylock-Squibbs, George A, Parker, Richard J, Buckner, Anne S M, Güdel, Manuel

“…ABSTRACT The ability to make meaningful comparisons between theoretical and observational data of star-forming regions is key to understanding the star…”
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STELLAR RADIO ASTRONOMY: Probing Stellar Atmospheres from Protostars to Giants by Guedel, M

“…Radio astronomy has provided evidence for the presence of ionized atmospheres around almost all classes of nondegenerate stars. Magnetically confined coronae…”
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CHANDRA AND XMM-NEWTON X-RAY OBSERVATIONS OF THE HYPERACTIVE T TAURI STAR RY TAU by Skinner, Stephen L., Audard, Marc, Güdel, Manuel

“…ABSTRACT We present results of pointed X-ray observations of the accreting jet-driving T Tauri star RY Tau using Chandra and XMM-Newton. We obtained…”
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CHANDRA RESOLVES THE T TAURI BINARY SYSTEM RW AUR by Skinner, Stephen L, Gudel, Manuel

“…RW Aur is a multiple T Tauri system consisting of an early-K type primary (A) and a K5 companion (B) at a separation of 1".4. RW Aur A drives a bipolar optical…”
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One Year in the Life of Young Suns: Data-constrained Corona-wind Model of κ1 Ceti by Airapetian, Vladimir S, Meng, Jin, Lüftinger, Theresa, Sudeshna Boro Saikia, Kochukhov, Oleg, Güdel, Manuel, Van Der Holst, Bart, Manchester, W

“…The young magnetically active solar-like stars are efficient generators of ionizing radiation in the form of X-ray and extreme-UV (EUV) flux, stellar wind, and…”
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Observations of a Radio-Quiet Solar Preflare by Benz, Arnold O., Battaglia, Marina, Güdel, Manuel

“…The preflare phase of the flare SOL2011-08-09T03:52 is unique in its long duration, in that it was covered by the Reuven Ramaty High Energy Solar Spectroscopic…”
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