From SOHO coronagraph C2 and C3 data at:
https://sohodata.nascom.nasa.gov/cgi-bin/data_query
Many thanks
...
Hercules A
Radio-Optical View of the Galaxy Hercules A - Many thanks to: NASA, ESA, S. Baum and C. O'Dea (RIT), R. Perley and W. Cotton (NRAO/AUI/NSF), and the Hubble Heritage Team (STScI/AURA)
Showing posts with label Solar flares. Show all posts
Showing posts with label Solar flares. Show all posts
Wednesday, September 6, 2017
X9 flare coronal mass ejection at SOHO coronagraphs 170906
....
From SOHO coronagraph C2 and C3 data at:
https://sohodata.nascom.nasa.gov/cgi-bin/data_query
Many thanks
...
From SOHO coronagraph C2 and C3 data at:
https://sohodata.nascom.nasa.gov/cgi-bin/data_query
Many thanks
...
Thursday, October 8, 2015
About the evolution of the Sun active regions
As
the days go by, I frequently show details of active region magnetograms
images and charts, and other data, for active regions I think may be
suspect of initiating the radio events we study.
I started studying solar radio emission in 1966, I am not finished yet :)
The degree of activity frequently varies much from day to day and is a complex subject studied for many decades.
Lidia van Driel-Gesztelyi and Lucie May Green have published last month a "Living Review of Solar Physics" titled:
"Evolution of Active Regions" , 98 pages, including 17 pages of references, free to download at:
http://solarphysics.
http://solarphysics.
Section 6 studies the case of AR 7978, "...subjected to the most comprehensive analysis of any AR..." as it evolved over a 6 month period.
Appendix A is a very good summary of Sunspot classifications, including the McIntosh and Hale methods.
I leave you repeating their quote from a poem by Laszlo Detre :
“ A Solar Physicist’s Lament ....
It looks as if many a sunny day
Will pass along on its way
Before we solve it all... "
My ignorance is vast
Have a wonderful day
Victor :)
------------------------------
Solar Dynamics Observatory - Now and Daily - Images Movies
http://sdo.gsfc.nasa.gov/data/
Solar Type Examples
http://herrero-radio-
Comparison of Cycles 23 and 24 sunspot and coronal mass ejection numbers
http://3.bp.blogspot.com/-
http://sidc.oma.be/cactus/ CACTUS page
Introductory Radio Astronomy references
http://herrero-radio-
My recent event posts by month:
http://herrero-radio-
http://herrero-radio-
http://herrero-radio-
http://herrero-radio-
http://herrero-radio-
http://herrero-radio-
Links to earlier posts by month:
http://herrero-radio-
------------------------------
Sunday, September 27, 2015
Reference to a study of herringbones in Type II event on 2011 September 22 related to an X1.4 flare
With many thanks I refer to :
Carley Reid Vilmer Gallagher 2015, "Low frequency radio observations of bi-directional electron beams in the solar corona"
http://arxiv.org/abs/1508.01065
http://adsabs.harvard.edu/cgi-bin/bib_query?arXiv:1508.01065
66 references at:
http://adsabs.harvard.edu/cgi-bin/nph-ref_query?bibcode=2015A%26A...581A.100C&refs=REFERENCES&db_key=AST
......
Carley Reid Vilmer Gallagher 2015, "Low frequency radio observations of bi-directional electron beams in the solar corona"
http://arxiv.org/abs/1508.01065
http://adsabs.harvard.edu/cgi-bin/bib_query?arXiv:1508.01065
66 references at:
http://adsabs.harvard.edu/cgi-bin/nph-ref_query?bibcode=2015A%26A...581A.100C&refs=REFERENCES&db_key=AST
......
Tuesday, June 9, 2015
Wednesday, May 20, 2015
Dynamics of flares and fine structure of solar radio emission 30-7000 MHz
Dynamics of flares and fine structure of solar radio emission 30-7000 MHz
I refer to Gennady Chernov, Valery Fomichev, Baolin Tan, Yihua Yan, Chengming Tan, Qijun Fu, 2014 :
http://arxiv.org/abs/1409.0660
http://adsabs.harvard.edu/cgi-bin/bib_query?arXiv:1409.0660
36 references at:
http://adsabs.harvard.edu/cgi-bin/nph-ref_query?bibcode=2015SoPh..290...95C&refs=REFERENCES&db_key=AST
Abstract: "Radiobursts exhibiting fine structure observed over two years during the rising phase of Cycle 24 by the Chinese Solar Broadband Radio Spectrometer (SBRS/Huairou) in the range 1 - 7.6 GHz and the spectrograph IZMIRAN in the meter range (25 - 270 MHz) are analyzed. In five events the zebra structure, various fiber bursts, and fast pulsations were observed. These observations have great importance for testing different theoretical models of fine structure formation, as, for example, only for explaining the zebra structure more than ten mechanisms have been proposed. The events on 15 and 24 February 2011 are of the greatest interest. In the course of the flare on 15 February (which occurred close to the center of disk) the zebra structure was observed during three sequential flare brightenings. The polarization changed sign in the third. This behavior of polarization combined with images of the corresponding flare brightenings, obtained in extreme ultraviolet radiation by the Solar Dynamics Observatory (SDO/AIA, 171 Å), provides important clues. The polarization of radio emission in all three cases is related to the ordinary wave mode of radio emission. The zebra structure was present at frequencies 190 - 220 MHz in the Culgoora spectrum. The event on 24 February 2011 is remarkable, as the zebra structure at frequencies of 2.6 - 3.8 GHz was not polarized and it appeared during the magnetic reconnection observed by SDO/AIA 171 Å in this limb flare. In the event on 9 August 2011, for the first time, a superfine millisecond structure was registered simultaneously in the fast pulsations and the stripes of the zebra structure. In the event on 1 August 2010 after the zebra structure two families of fibers bursts with opposite frequency drifts were observed. On 19 April 2012 the fibers against the background of type III bursts were observed by IZMIRAN and Nançay spectrographs. In the band of 42 - 52 MHz a group of nine slowly drifting narrow-band (</˜ 1 MHz) fibers formed a unique type II burst. Almost all events in the microwave range contain superfine structure in the form of the millisecond spikes, whose emission should be considered primary. It is possible that each type of fine structure is excited by the same mechanism, and the broad variety of events observed is related to the dynamics of flare processes."
I refer to Gennady Chernov, Valery Fomichev, Baolin Tan, Yihua Yan, Chengming Tan, Qijun Fu, 2014 :
http://arxiv.org/abs/1409.0660
http://adsabs.harvard.edu/cgi-bin/bib_query?arXiv:1409.0660
36 references at:
http://adsabs.harvard.edu/cgi-bin/nph-ref_query?bibcode=2015SoPh..290...95C&refs=REFERENCES&db_key=AST
Abstract: "Radiobursts exhibiting fine structure observed over two years during the rising phase of Cycle 24 by the Chinese Solar Broadband Radio Spectrometer (SBRS/Huairou) in the range 1 - 7.6 GHz and the spectrograph IZMIRAN in the meter range (25 - 270 MHz) are analyzed. In five events the zebra structure, various fiber bursts, and fast pulsations were observed. These observations have great importance for testing different theoretical models of fine structure formation, as, for example, only for explaining the zebra structure more than ten mechanisms have been proposed. The events on 15 and 24 February 2011 are of the greatest interest. In the course of the flare on 15 February (which occurred close to the center of disk) the zebra structure was observed during three sequential flare brightenings. The polarization changed sign in the third. This behavior of polarization combined with images of the corresponding flare brightenings, obtained in extreme ultraviolet radiation by the Solar Dynamics Observatory (SDO/AIA, 171 Å), provides important clues. The polarization of radio emission in all three cases is related to the ordinary wave mode of radio emission. The zebra structure was present at frequencies 190 - 220 MHz in the Culgoora spectrum. The event on 24 February 2011 is remarkable, as the zebra structure at frequencies of 2.6 - 3.8 GHz was not polarized and it appeared during the magnetic reconnection observed by SDO/AIA 171 Å in this limb flare. In the event on 9 August 2011, for the first time, a superfine millisecond structure was registered simultaneously in the fast pulsations and the stripes of the zebra structure. In the event on 1 August 2010 after the zebra structure two families of fibers bursts with opposite frequency drifts were observed. On 19 April 2012 the fibers against the background of type III bursts were observed by IZMIRAN and Nançay spectrographs. In the band of 42 - 52 MHz a group of nine slowly drifting narrow-band (</˜ 1 MHz) fibers formed a unique type II burst. Almost all events in the microwave range contain superfine structure in the form of the millisecond spikes, whose emission should be considered primary. It is possible that each type of fine structure is excited by the same mechanism, and the broad variety of events observed is related to the dynamics of flare processes."
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