Related papers: Prolonged and Extremely Non-radial Solar Wind Flow…
Context: Giant-cell convection is believed to be an important component of solar dynamics. For example, it is expected to play a crucial role in maintaining the Sun's differential rotation. Aims: We re-examine early reports of giant…
Chapman's (1957) conductive model of the solar corona is characterized by a temperature varying as r**(-2/7) with heliocentric distance r. The density distribution in this non-isothermal hydrostatic model has a minimum value at 123 RS, and…
This paper presents the analysis of 3D evolution of solar wind density turbulence and speed at various levels of solar activity between solar cycles 22 and 24. The solar wind data has been obtained from interplanetary scintillation (IPS)…
Universal small-scale solar activity in quiet region are suggested to be a potential source of solar wind and the upper solar atmosphere. Here, with the high-resoltion 174 \AA~imaging observations from the Solar Orbiter/Extreme Ultraviolet…
Information on the rotation rate of the corona, and its variation over latitude and solar cycle, is valuable for making global connections between the corona and the Sun, for global estimates of reconnection rates, and as a basic parameter…
We study the properties and geoeffectiveness of solar wind high-speed streams (HSSs) emanating from coronal holes and associated with stream interaction regions (SIRs). This paper presents a statistical study of 588 SIR/HSS events with…
A canonical description of a corotating solar wind high speed stream, in terms of velocity profile, would indicate three main regions:a stream interface or corotating interaction region characterized by a rapid flow speed increase and by…
Solar wind models predict that the mass flux carried away from the Sun in the solar wind should be extremely sensitive to the temperature in the corona, where the solar wind is accelerated. We perform a direct test of this prediction in…
We present direct evidence for the detection of the main energy release site in a non-eruptive solar flare, SOL2013-11-09T06:38UT. This GOES C2.7 event was characterised by two flaring ribbons and a compact, bright coronal source located…
Although the origins of slow solar wind are unclear, there is increasing evidence that at least some of it is released in a steady state on over-expanded coronal hole magnetic field lines. This type of slow wind has similar properties to…
We resolve the paradox that although magnetic collimation of an isotropic solar wind results in an enhancement of its proton flux along the polar directions, several observations indicate a wind proton flux peaked at the equator. To that…
The properties of the solar wind, as measured in situ throughout the heliosphere, depend both on the characteristics of its coronal source and on the intrinsic processes governing its interplanetary evolution. Recently, radial and Parker…
The dynamics of the solar wind depends intrinsically on the structure of the global solar magnetic field, which undergoes fundamental changes over the 11-yr solar cycle. For instance, the wind terminal velocity is thought to be…
This paper presents results of comparison between observations of coronal holes in the UV (SOHO EIT) and microwave emission (17, 5.7 GHz, 327 and 150.9 MHz, NoRH, SSRT and Nancy radioheliographs), and solar wind parameters, according to the…
It is recently noted that solar eruptions can be associated with the contraction of coronal loops that are not involved in magnetic reconnection processes. In this paper, we investigate five coronal eruptions originating from four sigmoidal…
Large amplitude whistler waves at frequencies of 0.2 to 0.4 times electron cyclotron frequency are frequently observed in the solar wind. The waves are obliquely propagating close to the resonance cone, with significant electric fields…
The origin of switchbacks in the solar wind is discussed in two classes of theory that differ in the location of the source being either in the transition region near the Sun or in the solar wind, itself. The two classes of theory differ in…
We present a further investigation into the increased ionization observed in element charge states in the fast solar wind compared to its coronal hole source regions. Once ions begin to be perpendicularly heated by ion cyclotron waves and…
We present observations of the extended solar cycle activity in white-light coronagraphs, and compare them with the more familiar features seen in the Fe XIV green-line corona. We show that the coronal activity zones seen in the emission…
The Sun is a highly dynamic environment that exhibits dynamic behavior on many different timescales. In particular, coronal holes exhibit temporal and spatial variability. Signatures of these coronal dynamics are inherited by the coronal…