scholarly journals Contribution of polar plumes to fast solar wind

2020 ◽  
Vol 643 ◽  
pp. A104
Author(s):  
L. Zangrilli ◽  
S. M. Giordano
Keyword(s):  
Solar Wind ◽  
Physical Properties ◽  
Solar Corona ◽  
Single Case ◽  
Field Of View ◽  
Fast Solar Wind ◽  
Self Consistent ◽  
Context Data ◽  
Polar Plumes ◽  
Early Phases

Context. Several physical properties of solar polar plumes have been identified by different published studies, however such studies are rare and sometimes in disagreement. Aims. The purpose of the present work is to analyze a set of SOHO/UVCS data dedicated to the observation of plumes and to obtain a picture of the physical properties of plumes in the intermediate solar corona through a self-consistent analysis. Methods. We applied the Doppler Dimming technique to data acquired by SOHO/UVCS in April 1996, which was during the very early phases of the mission. From this we derived outflow speeds and electron densities. We used SOHO/LASCO images as context data in order to better identify plume and interplume regions in the UVCS field of view. Results. The results we obtain demonstrate that in three cases out of four plumes expand with outflow speeds comparable to those of interplumes, and in a single case with lower speeds. We estimate that the contribution of plumes to the wind coming from the solar poles is about 20%, and that different plumes provide a different contribution, possibly according to different stages of their evolution. Conclusions. We conclude that plumes are not static structures, and that they contribute significantly to the wind coming from the solar poles.

scholarly journals Off-limb EUV observations of the solar corona and transients with the CORONAS-F/SPIRIT telescope-coronagraph

2008 ◽  
Vol 26 (10) ◽  
pp. 3007-3016 ◽  
Author(s):  
V. Slemzin ◽  
O. Bougaenko ◽  
A. Ignatiev ◽  
S. Kuzin ◽  
A. Mitrofanov ◽  
...  
Keyword(s):  
Solar Wind ◽  
Solar Corona ◽  
White Light ◽  
Extreme Ultraviolet ◽  
Temporal Correlation ◽  
Intermediate Region ◽  
Fast Solar Wind ◽  
Radial Line ◽  
Streamer Belt ◽  
The West

Abstract. The SPIRIT telescope aboard the CORONAS-F satellite (in orbit from 26 July 2001 to 5 December 2005), observed the off-limb solar corona in the 175 Å (Fe IX, X and XI lines) and 304 Å (He II and Si XI lines) bands. In the coronagraphic mode the mirror was tilted to image the corona at the distance of 1.1...5 Rsun from the solar center, the outer occulter blocked the disk radiation and the detector sensitivity was enhanced. This intermediate region between the fields of view of ordinary extreme-ultraviolet (EUV) telescopes and most of the white-light (WL) coronagraphs is responsible for forming the streamer belt, acceleration of ejected matter and emergence of slow and fast solar wind. We present here the results of continuous coronagraphic EUV observations of the solar corona carried out during two weeks in June and December 2002. The images showed a "diffuse" (unresolved) component of the corona seen in both bands, and non-radial, ray-like structures seen only in the 175 Å band, which can be associated with a streamer base. The correlations between latitudinal distributions of the EUV brightness in the corona and at the limb were found to be high in 304 Å at all distances and in 175 Å only below 1.5 Rsun. The temporal correlation of the coronal brightness along the west radial line, with the brightness at the underlying limb region was significant in both bands, independent of the distance. On 2 February 2003 SPIRIT observed an expansion of a transient associated with a prominence eruption seen only in the 304 Å band. The SPIRIT data have been compared with the corresponding data of the SOHO LASCO, EIT and UVCS instruments.

The Contribution of Polar Plumes to the Fast Solar Wind

2003 ◽  
Vol 589 (1) ◽  
pp. 623-634 ◽  
Author(s):  
A. H. Gabriel ◽  
F. Bely‐Dubau ◽  
P. Lemaire
Keyword(s):  
Solar Wind ◽  
Fast Solar Wind ◽  
Polar Plumes

Alfvénic waves with sufficient energy to power the quiet solar corona and fast solar wind

Nature ◽  
2011 ◽  
Vol 475 (7357) ◽  
pp. 477-480 ◽  
Author(s):  
Scott W. McIntosh ◽  
Bart De Pontieu ◽  
Mats Carlsson ◽  
Viggo Hansteen ◽  
Paul Boerner ◽  
...  
Keyword(s):  
Solar Wind ◽  
Solar Corona ◽  
Fast Solar Wind ◽  
Sufficient Energy

Modeling proton and electron heating in the fast solar wind

2020 ◽  
Author(s):  
L. Adhikari ◽  
G.P. Zank ◽  
L.-L. Zhao ◽  
M. Nakanotani ◽  
S. Tasnim
Keyword(s):  
Solar Wind ◽  
Fast Solar Wind ◽  
Electron Heating

A Calculation real abundance of gaseous elements of the comet PanSTARRS C/2011 S4

2020 ◽  
Vol 18 (45) ◽  
pp. 21-31
Author(s):  
Salman Zaidan Khalaf ◽  
Khaleel Abrahim ◽  
Imad Kassar Akeab
Keyword(s):  
Solar Wind ◽  
Physical Properties ◽  
Atomic Number ◽  
Mathematic Model ◽  
Emission Energy ◽  
X Ray ◽  
The Real

    X-ray emission contains some of the gaseous properties is produced when the particles of the solar wind strike the atmosphere of comet ISON and PanSTARRS Comets. The data collected with NASA Chandra X-ray Observatory of the two comets, C/2012 S1 (also known as Comet ISON) and C/2011 S4 (Comet PanSTARRS) are used in this study.    The real abundance of the observed X-ray spectrum elements has been extracted by a new simple mathematic model. The study found some physical properties of these elements in the comet’s gas such as a relationship between the abundance with emitted energy. The elements that have emission energy (2500-6800) eV, have abundance (0.1-0.15) %, while the elements that have emission energy (850-2500) eV and (6800-9250) eV have abundance (0.2-0.3) %.    The relation between interacted energy and atomic number is form two sets.  The interacted energy of each element is increased as the atomic number increased. This case has been seen in both comets

Early Observations from the Solar Orbiter SWA/Electron Analyser System

2021 ◽  
Author(s):  
Christopher Owen ◽  
Keyword(s):  
Solar Wind ◽  
Field Vector ◽  
Field Of View ◽  
High Time Resolution ◽  
Angle Distribution ◽  
Pitch Angle Distribution ◽  
Burst Mode ◽  
Steering Mechanism ◽  
Operational Issues ◽  
Electrostatic Analyser

<p>Solar Orbiter carries a total of 10 instrument suites making up the payload for the mission.  One of these, the Solar Wind Analyser (SWA) instrument, is comprised of 3 sensor units which are together served by a central DPU unit.  Of particular focus in this presentation are the early measurements from one of these sensors, the Electron Analyser System (EAS).  EAS is a dual-head, top-hat electrostatic analyser system that is capable of making 3D measurements of solar wind electrons at energies below ~5 keV from a vantage point at the end of a 4-metre boom extending into the shadow of the spacecraft.  The sensor was accommodated in this location to both maximise the unobstructed field of view and to minimise the effect of spacecraft related disturbances on the low-energy (less than a few tens of eV) electrons expected the core population of the solar wind.</p><p>To date the SWA instrument sensors have operated sporadically during the mission cruise phase, which began in June 2020.  This is due to a number of operational issues faced by the SWA team, which mean we have not been able to take data in a continuous manner.  However, the data that has been taken shows the clear promise of the SWA measurements, in general, once these issues can be overcome.  For example, EAS is using a novel sample steering mechanism in burst mode which, with reference to a magnetic field vector shared onboard by the MAG instrument, allows the capture of the electron pitch angle distribution at unusually high time resolution.  We discuss these observations here, and illustrate the potential science returns from the burst mode.  We also present results from the new EAS observations in the vicinity of reconnecting current sheets in the solar wind, to more generally illustrate the capability of the sensor. </p>

Sign in / Sign up

Export Citation Format

Share Document