中文
相关论文

相关论文: Evidence of Wave Damping at Low Heights in a Polar…

200 篇论文

We present a measurement of the energy carried and dissipated by Alfv\'en waves in a polar coronal hole. Alfv\'en waves have been proposed as the energy source that heats the corona and drives the solar wind. Previous work has shown that…

太阳与恒星天体物理 · 物理学 2015-06-15 Michael Hahn , Daniel W. Savin

Context. We diagnose the properties of the plume and interplume regions in a polar coronal hole and the role of waves in the acceleration of the solar wind. Aims. We attempt to detect whether Alfven waves are present in the polar coronal…

太阳与恒星天体物理 · 物理学 2015-05-13 D. Banerjee , D. Perez-Suarez , J. G. Doyle

The Alfv\'en wave energy flux in the corona can be explored using the electron density and velocity amplitude of the waves. The velocity amplitude of Alfv\'en waves can be obtained from the non-thermal velocity of the spectral line…

太阳与恒星天体物理 · 物理学 2019-07-03 Girjesh R. Gupta , G. Del Zanna , H. E. Mason

Ultraviolet spectroscopy of the extended solar corona is a powerful tool for measuring the properties of protons, electrons, and heavy ions in the accelerating solar wind. The large coronal holes that expand up from the north and south…

太阳与恒星天体物理 · 物理学 2020-07-28 Steven R. Cranmer

Alfven waves and ion-cyclotron absorption of high-frequency waves are frequently brought into models devoted to coronal heating and fast solar-wind acceleration. Signatures of ion-cyclotron resonance have already been observed in situ in…

天体物理学 · 物理学 2009-11-13 L. Dolla , J. Solomon

We focus on a polar coronal hole region to find any evidence of dissipation of propagating slow magneto-acoustic waves. We obtained time-distance and frequency-distance maps along the plume structure in a polar coronal hole. We also…

太阳与恒星天体物理 · 物理学 2014-09-05 G. R. Gupta

Observations reveal an increase with height of the line width of several coronal spectral lines probably caused by outwardly propagating Alfv{\'e}n waves. However, the spectral line width sometimes shows a sudden decrease at a height…

天体物理学 · 物理学 2008-11-26 T. V. Zaqarashvili , R. Oliver , J. L. Ballester

(abridged) We investigate how the properties of the corona and solar wind in the open coronal holes depend on the properties of the magnetic fields and their footpoint motions at the surface, by perfoming 1D MHD simulations from the…

天体物理学 · 物理学 2015-06-24 Takeru K. Suzuki , Shu-ichiro Inutsuka

The discovery of ubiquitous low-frequency (3-5mHz) Alfvenic waves in the solar chromosphere (with Hinode/SOT), and corona (with CoMP and the Solar Dynamics Observatory, SDO) has provided some insight into the non-thermal energy content of…

太阳与恒星天体物理 · 物理学 2015-06-12 Scott W. McIntosh , Bart De Pontieu

We study the impulsively generated non-linear Alfv\'en waves in the solar atmosphere, and describe their most likely role in the observed non-thermal broadening of some spectral lines in solar coronal holes. We solve numerically the…

太阳与恒星天体物理 · 物理学 2015-06-05 P. Chmielewski , A. K. Srivastava , K. Murawski , Z. E. Musielak

We investigate off-limb active region and quiet Sun corona using spectroscopic data. Active region is clearly visible in several spectral lines formed in the temperature range of 1.1--2.8 MK. We derive electron number density using line…

太阳与恒星天体物理 · 物理学 2017-02-07 G. R. Gupta

Coronal holes are the dark patches in the solar corona associated with relatively cool, less dense plasma and unipolar fields. The fast component of the solar wind emanates from these regions. Several observations reveal the presence of…

太阳与恒星天体物理 · 物理学 2016-03-09 D. Banerjee , S. Krishna Prasad

Coronal holes are the darkest and least active regions of the Sun, as observed both on the solar disk and above the solar limb. Coronal holes are associated with rapidly expanding open magnetic fields and the acceleration of the high-speed…

太阳与恒星天体物理 · 物理学 2015-05-14 Steven R. Cranmer

Between February 24-25, 2009, the EIS spectrometer onboard the Hinode spacecraft performed special "sit & stare" observations above the South polar coronal hole continuously over more than 22 hours. Spectra were acquired with the 1" slit…

太阳与恒星天体物理 · 物理学 2012-08-28 Bemporad Alessandro , Abbo Lucia

We consider compressive viscosity and thermal conductivity to study the propagation and dissipation of long period slow longitudinal MHD waves in polar coronal holes. We discuss their likely role in the line profile narrowing, and in the…

天体物理学 · 物理学 2008-11-26 B. N. Dwivedi , A. K. Srivastava

To study the dynamics of coronal holes and the role of waves in the acceleration of the solar wind, spectral observations were performed over polar coronal hole regions with the SUMER spectrometer on SoHO and the EIS spectrometer on Hinode.…

太阳与恒星天体物理 · 物理学 2009-05-08 D. Banerjee , L. Teriaca , G. R. Gupta , S. Imada , G. Stenborg , S. K. Solanki

We have measured the energy and dissipation of Alfvenic waves in the quiet Sun. A magnetic field was used to infer the location and orientation of the magnetic field lines along which the waves are expected to travel. The waves were…

太阳与恒星天体物理 · 物理学 2015-06-22 Michael Hahn , Daniel Wolf Savin

Coronal loops trace out bipolar, arch-like magnetic fields above the Sun's surface. Recent measurements that combine rotational tomography, extreme ultraviolet imaging, and potential-field extrapolation have shown the existence of large…

太阳与恒星天体物理 · 物理学 2016-11-15 Avery J. Schiff , Steven R. Cranmer

We investigate the occurrence of a CME-driven coronal dimming using unique high resolution spectral images of the corona from the Hinode spacecraft. Over the course of the dimming event we observe the dynamic increase of non-thermal line…

天体物理学 · 物理学 2011-02-11 Scott W. McIntosh

Alfv\'enic waves are known to be prevalent throughout the corona and solar wind. Determining the Poynting flux supplied by the waves is required for constraining their role in plasma heating and acceleration, as well as providing a…

太阳与恒星天体物理 · 物理学 2025-01-24 Richard J. Morton , Micah J. Weberg , N. Balodhi , James A. McLaughlin
‹ 上一页 1 2 3 10 下一页 ›