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Related papers: New aspects of Doppler imaging in Sun-as-a-star ob…

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Radial velocity observations of stars are entering the sub-m/s domain revealing fundamental barriers for Doppler precision experiments. Observations of the Sun as a star can easily overcome the m/s photon limit but face other obstacles. We…

Instrumentation and Methods for Astrophysics · Physics 2016-06-29 Ulrike Lemke , Ansgar Reiners

It is well-known that the global acoustic oscillations of the Sun's atmosphere can excite resonance modes within large-scale magnetic concentrations. These structures are conduits of energy between the different layers of the solar…

Solar and Stellar Astrophysics · Physics 2025-05-14 M. Berretti , M. Stangalini , G. Verth , V. Fedun , S. Jafarzadeh , D. B. Jess , F. Berrilli

Precise, high-cadence, long-term records of stellar spectral variability at different temporal scales lead to better understanding of a wide variety of phenomena including stellar atmospheres and dynamos, convective motions, and rotational…

Solar and Stellar Astrophysics · Physics 2023-07-19 Serena Criscuoli , Sergey Marchenko , Matthew DeLand , Debi Choudhary , Greg Kopp

In this paper, we explore the observable signatures of solitonic boson stars by employing ray-tracing simulations, with celestial spheres and thin accretion disks serving as illumination sources. By numerically fitting the metric form, we…

General Relativity and Quantum Cosmology · Physics 2025-08-22 Ke-Jian He , Guo-Ping Li , Chen-Yu Yang , Xiao-Xiong Zeng

We present a new method that combines the results of an oscillation study made in optical and radio observations. The optical spectral measurements in photospheric and chromospheric lines of the line-of-sight velocity were carried out at…

Solar and Stellar Astrophysics · Physics 2015-03-18 V. E. Abramov-Maximov , G. B. Gelfreikh , N. I. Kobanov , K. Shibasaki , S. A. Chupin

We analyse the chromospheric Doppler velocity oscillations in a sunspot using the high resolution spectral observations obtained from the Fast Imaging Solar Spectrograph(FISS) of the New Solar Telescope at the Big Bear Solar Observatory.…

Solar and Stellar Astrophysics · Physics 2013-10-25 R. A. Maurya

Among the identified solar inertial modes, the high-latitude mode with azimuthal order $m=1$ (HL1) has the largest amplitude and plays a role in shaping the Sun's differential rotation profile. We aim to study the evolution of the HL1 mode…

Solar and Stellar Astrophysics · Physics 2025-03-12 Zhi-Chao Liang , Laurent Gizon

Comparing solar and stellar brightness variations is hampered by the difference in spectral passbands used in observations as well as by the possible difference in the inclination of their rotation axes from the line of sight. We calculate…

Solar and Stellar Astrophysics · Physics 2020-07-01 N. -E. Nèmec , E. Işık , A. I. Shapiro , S. K. Solanki , N. A. Krivova , Y. Unruh

We use 9.5-yr of BiSON Sun-as-a-star data to search for dependence of solar-cycle parameter changes on the angular degree, l, of the data. The nature of the Sun-as-a-star observations is such that for changes measured at fixed frequency, or…

Astrophysics · Physics 2009-11-11 D. Salabert , W. J. Chaplin , Y. Elsworth , R. New , G. A Verner

Observations of the Sun with the LOWL instrument provide a homogeneous set of solar p-mode frequencies from low to intermediate degree which allows one to determine the structure of much of the solar interior avoiding systematic errors that…

Small-scale magnetic flux concentrations contribute significantly to the brightness variations of the Sun, yet observing them - particularly their magnetic field - near the solar limb remains challenging. Solar Orbiter offers an…

Solar and Stellar Astrophysics · Physics 2026-02-11 K. Albert , J. Hirzberger , N. A. Krivova , X. Li , D. Calchetti , G. Valori , J. Sinjan , S. K. Solanki , A. Gandorfer , J. Woch , D. Orozco Suárez , S. Parenti

Solar limb and disc spicule quasi- periodic motions have been reported for a long time, strongly suggesting that they are oscillating. In order to clear up the origin and possibly explain some solar limb and disc spicule quasi-periodic…

Solar and Stellar Astrophysics · Physics 2015-05-27 E. Tavabi , S. Koutchmy , A. Ajabshirizadeh

Recent and upcoming stabilized spectrographs are pushing the frontier for Doppler spectroscopy to detect and characterize low-mass planets. Specifications for these instruments are so impressive that intrinsic stellar variability is…

Instrumentation and Methods for Astrophysics · Physics 2020-05-05 Christian Gilbertson , Eric B. Ford , Xavier Dumusque

We study in details the Earth matter effects on the boron neutrinos from the Sun using recently developed 3D models of the Earth. The models have a number of new features of the density profiles, in particular, a substantial deviation from…

High Energy Physics - Phenomenology · Physics 2020-07-08 Pouya Bakhti , Alexei Yu. Smirnov

Measurements from the Solar Irradiance Monitor (SIM) onboard the SORCE mission indicate that solar spectral irradiance at Visible and IR wavelengths varies in counter phase with the solar activity cycle. The sign of these variations is not…

Solar and Stellar Astrophysics · Physics 2015-06-19 Serena Criscuoli , Han Uitenbroek

The development of space-borne missions has significantly improved the quality of the measured spectra of solar-like oscillators. Their $p$-mode line profiles can now be resolved, and the asymmetries inferred for a variety of stars other…

Solar and Stellar Astrophysics · Physics 2021-01-04 J. Philidet , K. Belkacem , H. -G. Ludwig , R. Samadi , C. Barban

NASA's Solar Dynamics Observatory is delivering vector field observations of the full solar disk with unprecedented temporal and spatial resolution; however, the satellite is in a highly inclined geostationary orbit. The relative…

Solar and Stellar Astrophysics · Physics 2016-06-01 P. W. Schuck , Spiro Antiochos , K. D. Leka , Graham Barnes

The measurement of Doppler velocities in spectroscopic solar observations requires a reference for the local frame of rest. The rotational and radial velocities of the Earth and the rotation of the Sun introduce velocity offsets in the…

Solar and Stellar Astrophysics · Physics 2015-05-27 Jaime de la Cruz Rodríguez , Dan Kiselman , Mats Carlsson

We describe a global parametric model for the observed power spectra of solar oscillations of intermediate and low degree. A physically motivated parameterization is used as a substitute for a direct description of mode excitation and…

Solar and Stellar Astrophysics · Physics 2015-06-17 Sergei V. Vorontsov , Stuart M. Jefferies