Results 81 to 90 of about 22,416 (198)

Does the butterfly diagram indicate asolar flux-transport dynamo?

, 2004
We address the question whether the properties of the observed latitude-time diagram of sunspot occurence (the butterfly diagram) provide evidence for the operation of a flux-transport dynamo, which explains the migration of the sunspot zones and the ...
D. Schmitt, Ferriz-Mas, Ferriz-Mas, Haber, Hathaway, Hoyng, M. Schüssler, Ossendrijver, Schmitt, Schmitt, Schüssler, Solanki   +11 more
core   +1 more source

Modulation of the Mid‐Latitude Ionospheric Sporadic E Layer by the Northern Polar Vortex

Geophysical Research Letters, Volume 53, Issue 4, 28 February 2026.
Abstract The sporadic E (Es) layer is a prominent ionospheric irregularity mainly driven by vertical wind shear at mid‐latitudes. Hereby we statistically investigate for the first time Es responses to variations of the northern polar vortex (represented by NAM index) using long‐term ionosonde observations over Japan (44 years) and Australia (34 years).
Tomoki Maeda, Huixin Liu, Yosuke Yamazaki, Lihui Qiu   +3 more
wiley   +1 more source

Magnetic Fields in the Solar Convection Zone

Living Reviews in Solar Physics, 2009
Active regions on the solar surface are generally thought to originate from a strong toroidal magnetic field generated by a deep seated solar dynamo mechanism operating at the base of the solar convection zone.
Yuhong Fan
doaj  

How Does the Magnetosphere‐Ionosphere Current System Respond to Solar Flares?

Geophysical Research Letters, Volume 53, Issue 4, 28 February 2026.
Abstract While the isolated effects of solar flares on low‐latitude ionospheric electrodynamics have been well documented, the coupled system response of the equatorial electrojet (EEJ), auroral electrojet (AEJ), field‐aligned currents (FACs), and asymmetric ring current (ASY‐H) remains poorly understood.
Hongkai Tang, Jing Liu, Xuanqing Liu, Xiangyu Niu, Jiawei Zhang, Shuhan Li   +5 more
wiley   +1 more source

Quasi-biennial oscillations and Rieger-type periodicities in a Babcock–Leighton solar dynamo

Astronomy & Astrophysics
Context. The Sun’s magnetic field exhibits the 11 year solar cycle as well as shorter periodicities, popularly known as the quasi-biennial oscillations (QBOs) and Rieger-type periods.
Kumar Pawan, Ravindra Belur, Chowdhury Partha, Karak Bidya Binay   +3 more
doaj   +1 more source

Differential rotation and meridional flow of Arcturus

, 2010
The spectroscopic variability of Arcturus hints at cyclic activity cycle and differential rotation. This could provide a test of current theoretical models of solar and stellar dynamos. To examine the applicability of current models of the flux transport
Brown, Charbonneau, Chatterjee, Dikpati, Gray, Gray, Griffin, Kichatinov, Kitchatinov, Kitchatinov, Kitchatinov, Kitchatinov, Küker, Küker, Küker, Miesch, Ossendrijver, Trimble, Worley, Yoshimura   +19 more
core   +1 more source

Sound Velocities of FeO‐Bearing Ringwoodite and Majorite: Implication for Martian Mantle Seismic Profiles

Geophysical Research Letters, Volume 53, Issue 3, 16 February 2026.
Abstract Compressional and shear wave velocities (Vp, Vs) of candidate Martian deep‐mantle minerals, FeO‐rich ringwoodite ((Mg0.66Fe0.34)2SiO4) and majorite (Mg0.75Fe0.10Al0.26Ca0.07Si0.84O3), were measured up to 25 GPa and 700 K using Brillouin light scattering coupled with externally‐heated diamond anvil cells.
Luo Li, Takayuki Ishii, Young Jay Ryu, Dongzhou Zhang, Stella Chariton, Vitali B. Prakapenka, Jung‐Fu Lin   +6 more
wiley   +1 more source

Dynamo Confinement of a Radiatively Spreading Solar Tachocline Revealed by Self-consistent Global Simulations

The Astrophysical Journal Letters
The helioseismically observed solar tachocline is a thin internal boundary layer of shear that separates the rigidly rotating solar radiative zone from the differentially rotating convective zone and is believed to play a central role in the 22-yr solar ...
Loren I. Matilsky, Lydia Korre, Nicholas H. Brummell   +2 more
doaj   +1 more source

A Model of the Double Magnetic Cycle of the Sun

, 1998
It has been argued that the solar magnetic cycle consists of two main periodic components: a low-frequency component (Hale's 22-year cycle) and a high-frequency component (quasi-biennial cycle).
Benevolenskaya E. E., Benevolenskaya E. E., E. E. Benevolenskaya, Gnevyshev M. N., Kleeorin N. I.   +4 more
core   +2 more sources

Topside Ionospheric Ambipolar Diffusion Derived From ICON Observations

Geophysical Research Letters, Volume 53, Issue 3, 16 February 2026.
Abstract The scarcity of ambipolar diffusion observations has constrained our understanding of ionospheric physical processes. We present the first comprehensive analysis of topside ionospheric ambipolar diffusion using the difference between the field‐aligned ion drifts and neutral winds observed by the Ionospheric Connection Explorer (ICON) satellite.
Rongjin Du, Libo Liu, Ruilong Zhang, Wenbo Li, Jing Liu, Bowei Liu, Yiding Chen, Han Ma, Huijun Le   +8 more
wiley   +1 more source