A1D3.1
Lead Beneficiary: LPI
Beneficiaries involved: KULeuven, UNIGRAZ, HVAR, UGOE, SRC-PAS, OBSPARIS, ROB
Due Date: month 12
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Contents |
Goal
The online report on results of the Task 3.5. The goal of this task is a study of the morphology and evolution of pre-eruptive coronal and chromospheric structures, energy loading, electric currents and helicity, temperature structure of postflare loop systems, analysis of signatures of the current sheet formation and reconnection in hard X-rays and radio emission, radio signatures of the particle acceleration.
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Successes
LPI, SRC-PAS
On January 30, the Russian CORONAS-PHOTON satellite was successively launched. It carries the TESIS EUV telescope/spectroheliograph and the SphinX X-ray spectrophotometer for studies of solar activity processes in the current 24th solar cycle. During the period from the launch till now the instruments are functioning successfully. The data were demonstrated at the SOTERIA meeting and several workshops and are available now at the sites: http://www.tesis.lebedev.ru (TESIS catalog) and http://156.17.94.1/sphinx_catalogue/SphinX_cat_main.html (SphinX catalogue)
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Exceptional Discoveries
SRC-PAS, LPI
Due to unprecedented sensitivity of SphinX detectors in comparison with the standard GOES X-ray photometers, many flares have been observed with their peak intensities much below the GOES detection threshold. Two new activity classes: SQ (1.10-10 W/m2) and S (1.10-9 W/m2) were introduced extending two orders of magnitude below the lowest presently used A1 level. At the extremely low solar activity level TESIS observed with high cadence (5 min) several giant prominence eruptions in He II 304 Å band and the structure of EUV solar corona at the distances up to 2 RSun.
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Progress so far
All teams
The D3.1 online report "Energy release through flares and CMEs, their evolution and geo-space impact parameters for special events" has been prepared and released in accordance with the SOTERIA working plan.
LPI
1. LPI is a leading beneficiary to prepare the online report together with all involved teams.
2. The list of selected events for analysis and numerical simulations was created and discussed for further analysis within WP3 in collaboration with the WP4.
3. The TESIS experiment on solar imaging XUV spectroscopy successfully started on 30 January 2009. During February-October 2009 more than 300 thousands of solar images were obtained with the total volume of 500 Gbytes. Several giant prominence eruptions registered in the 304 Å spectral channel (17 and 23 April, 12 May, 14 June, 26 September). The high temperature channels 171 (Fe IX-X) and 132 Å detected several flares including two most powerful in 2009 (5 June and 25 September).
4. New methods for the modeling of the hot coronal plasma structures based on full-Sun CORONAS-F /RES monochromatic images in the regions 176-207 and 280-330 A along with other XUV data (GOES, RHESSI) have been developed. The temperature composition and the differential emission measure functions for coronal plasma of active regions, flares and long-duration events have been determined in the temperature range log T(K) = 6.0 -7.3. The space-time dynamics of specific hot corona structures ( “spiders”), firstly observed in Mg XII monochromatic images was studied and modeled.
5. Particle acceleration in the solar corona has been studied in the framework of collapsing trap model taking into account the particle scattering and braking in the high-temperature plasma of solar flares. It was shown that collapsing magnetic traps are capable of confining from 20% (strong collisions) to 90% (collisionless approximation) of the injected particles in the corona for a long time. For collision times comparable to trap lifetimes the electron spectra above 10 keV have double-power-law shape. The coronal hard X-ray emission during solar flares theoretically interpreted under assumption that a fast plasma outflow from a reconnecting current sheet creates a shock wave above loops of strong magnetic field.The numerical model of solar-energetic-particle (SEP) acceleration is developed.
Persons involved: S. Kuzin, V. Slemzin, S. Bogachev, A. Urnov, A.Pertsov, A. Ignatiev, N. Sukhodrev, S, Shestov, F.Goryaev
KUleuven
2.5D viscous/resistive MHD simulations with compressive effects show that a current-sheet in the high Chromosphere/low Corona undergoes to a self-feeding mechanism [Lapenta 2008] driving the system from a slow to a fast reconnection regime [Bettarini & Lapenta 2008]. A final turbulent state is reached and this situation is a promising candidate to trigger solar explosive phenomena. Data point out the two-staged process comes with a significant release of accelerated plasma's structures and thermal energy distributed on turn in two steps during the fast regime: a slow increase in the energy fluxes (poynting, hentalpy, kinetic and momentum) followed by a impulsive event [Bettarini & Lapenta 2009] . This is characterized by a time scale of the order of 15 - 50 s and by the following physical values: mass flux ~ 0.8-2.4 x 10^(16) particle/cm^2 s; enthalpy flux ~ 0.6-7.2 x 10^7 erg/cm^2 s; kinetic flux ~ 1.7-22 x 10^7 erg/cm^2 s. Those values are consistent with observations of solar explosive phenomena [Tsuneta 1996, Shibata 1996]. References: Shibata, K. 1996, Adv. Space Res., 17, 9; Tsuneta, S. 1996, ApJ, 456, 840; Lapenta, G. 2008, Phys. Rev. Lett., 100, 235001; Bettarini, L. & Lapenta, G., 2009, ApJ., submitted.
Persons involved: G. Lapenta, L. Bettarini.
UNIGRAZ
Multi-wavelength observations of high temporal cadence are of vital importance when studying initiation and propagation mechanisms of coronal mass ejections (CMEs) and flares. It is recognized that CMEs and flares are closely related phenomena which have to be seen under the aspect of their common underlying magnetic processes. The construction of a Ca-II K telescope at Kanzelhöhe observatory will support, in addition to the existing (and improved) H-alpha patrol telescope, studies on the flare energy release and related CME initiation processes. The Ca-II K as well as the H-alpha data will be put at disposal to all SOTERIA participants. Progress for the installation of the Ca-K system at Kanzelhöhe about 30% (cf. D3.4).
Persons involved: Wolfgang Otruba, Werner Pötzi, Wolfgang Hirtenfellner, Heinrich Freislich, Manuela Temmer, Astrid Veronig, Arnold Hanslmeier
HVAR, UNIGRAZ, OBSPARIS, ROB
Multi-wavelength observations of six flare/CME events were studied to infere whether the associated coronal shock was ignited by the flare or launched by the CME. The analysis of the kinematics of high-frequency radio type II bursts (recorded by the Astrophysikalisches Institut Potsdam and the Nancay Radio Helioghraph), kinematics of low-height signatures of CMEs (observed by LASCO-C1; EIT), and the evolution of the energy release in the associated flares, showed that in four events the shock was ignited by the flare. In two events the results are not decissive. The results are foreseen to be published in the journal Astronomy & Astrophysics (already in preparation).
Persons involved: ROB (J. Magdalenic, Ch. Marque), HVAR (B. Vrsnak, T. Zic), UNIGRAZ (A. Veronig, M. Temmer), OBSPARIS (L. Klein), [non-soteria] AIP (H. Aurass).
HVAR, ROB, UNIGRAZ
To determine whether a particular shock was driven by the CME or ignited by the flare we preformed a multiwavelength study of large-scale coronal disturbances associated with several CME/flare events (vCME < 500 km/s). For seven events the kinematics and evolution of the shock wave signatures - metric type II radio bursts and EIT waves were analyzed in details and compared with the CME evolution and kinematics during the onset and early stage of the CME. The outcome is that the shock waves associated with four out of seven CME/flare events were probably not driven by the CME (all of them were slow CMEs), but initiated by the flare. In two studied events the flare was very well synchronized with the acceleration phase of the CME and it was not possible to give conclusive answer on the origin of the coronal shocks, in one event the shock wave was probably generated by the flare energy release.
Persons involved: Jasmina Magdalenić, Christoph Marqué and Andrei Zhukov (ROB), Bojan Vršnak and Tomislav Žic (HVAR), Astrid Veronig and Manuela Temmer (UNIGRAZ).
HVAR
Multi-wavelength observations of the acceleration phase of 18 CMEs are analyzed, to study the relative kinematics of the CME leading edge and the associated eruptive prominence. In 14 events (75%) the acceleration phases of the leading edge and the eruptive prominence are highly synchronized, whereas in the remaining four events we found a large mismatch. Results are presented in a paper Maricic, Vrsnak, & Rosa: "Relative Kinematics of the Leading Edge and the Prominence in Coronal Mass Ejections", which is published the journal Solar Physics (currently in press).
Persons involved: B. Vrsnak, T. Zic (and non-soteria D. Maricic and D. Rosa)
UGOE
CME event list for 3D studies established. Flux rope models successfully applied and extended into the heliosphere based on STEREO/SOHO multipoint space observations. First CME tracked all the way along the Sun-Earth line (STEREO and ACE observations).
Persons involved: V. Bothmer, A. Reiners.
SRC-PAS
The SRC-PAS Team has been and is busy with collecting and archiving the data from the SphinX spectrophotometer, aboard CORONAS-Photon. During first ~7 months of active operation the instrument collected ~35 GB of data, including small flares on March 26th and 4-6 July, 2009. The data analysis of 30 Aug. 2002 and 14 Nov. 2002 flares is in progress. Investigations of solar X-ray flux properties during the present solar minimum has been performed and publication submitted. The TRACE point spread function has been theoretically modeled for all EUV filters. Related algorithms have been written and made publicly accessible.
Summary by individual contributors:
- Jaroslaw Bakala: On line creation of the SphinX flare catalogue, containing already ~600 events. SphinX metadata preparation.
- Szymon Gburek: SphinX software development. Sphinx data archive and www catalogue maintenance/updates. Time stamping of SphinX measurements.
- Anna Kepa: Sphinx www catalogue maintenance.
- Zbigniew Kordylewski: Development and updates of orbital algorithms for the Coronas-Photon Mission. Automation of SphinX in-orbit operation.
- Miroslaw Kowalinski: On-line reformatting of SphinX telemetry data stream and respective algorithms refinement. Control of the on-board SphinX computer.
- Piotr Podgorski: Analysis of thermal environment within the SphinX instrument during early operations. Sphinx data archive and www catalogue maintenance/updates. Instrument health control.
- Marek Siarkowski: Calibration and interpretation of SphinX data.
- Barbara Sylwester: RESIK and SphinX data interpretation
-Janusz Sylwester: Sphinx project supervision. Development of the algorithms for SphinX data visualization and analysis. RESIK and SphinX data interpretation - results presented in [1].
-Witold Trzebinski: Laboratory simulation of SphinX electronics behavior under harsh thermal environment conditions. The calibration of the SphinX sensors temperature response. Updates of CORONAS-Photon orbital elements database.
-S. Plocieniak: Additional laboratory measurements of the SophinX EUV filter transmission. Studies of dead-layer for SphinX detectors.
References
1) The Sun’s X-ray emission during the present solar minimum,J. Sylwester, M. Kowalinski, S. Gburek, S. Kuzin, F. Farnik, F. Reale, K.J.H. Phillips,EOS, submitted
OBSPARIS
We have performed a 3D MHD simulation which suggests a new mechanism (based on a two-step magnetic reconnection process) for the formation of magnetic nullpoint fan-spine topologies in the solar corona. Such topologies are relevant for dynamic phenomena like coronal jets and specific flares, as well as for the formation of anemone active regions (small, typically bipolar regions within coronal holes). The paper is published (ApJ 704, 485 [2009]) and acknowledges the SOTERIA grant.
Persons involved: OBSPARIS: T. Török, G. Aulanier, B. Schmieder; non-SOTERIA: K.K. Reeves, L. Golub
We analyzed observations of the formation of two filaments - one active and one quiescent, and their subsequent interactions prior to eruption.
Person involved: L. van Driel-Gesztelyi
ROB
The PROBA2 platform, which is a technology demonstration mission of ESA, has been prepared for launch on November 2, 2009. The two main instruments onboard will monitor solar activity and radiance: the "Sun Watcher using APS and image Processing" (SWAP, an EUV imager) and the "Lyman alpha radiometer" (LYRA).
A large scale statistical analysis all CMEs detected by CACTus over cycle 23 (limited to the period Sept 1999- Jan 2007) has been performed. It turned out that the CACTus CME rate follows the overall solar cycle modulation and has no typical size (angular width) for a CME.
CACTus real-time detections are available for both LASCO and SECCHI data: http://sidc.be/cactus. We presented a one-dimensional, analytic model for current sheets that form during solar flares. The model uses a method developed by B. Somov and V. Titov for Petschek-type reconnection that reduces the full set of two-dimensional MHD equations to a single dimension by averaging the MHD equations across the current layer.
Common properties of the geospace impact of transient solar phenomena, including propagation of CMEs in the heliosphere, solar energetic particle propagation and magnetic connection to the source region, connection between solar and interplanetary phenomena and geomagnetic storm forecasting on the base of solar observations were analyzed.
Persons involved: D. Berghmans, D. Seaton, A. Zhukov.
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Problem areas
There is no special problems concerned D3.1. [edit]
Suggestions for spin-off, collaboration or improvement
LPI proposes to continue the studies on the task 3.5 (which intersect with other tasks of WP3) in collaborative groups from participaring WP3 members. In particular, we propose to carry out joint analysis of solar phenomena related to the special events selected together with WP4. To create collaborative groups and discuss their activity,a coordination meeting of WP3 members should be organized during the annual SOTERIA meeting in Davos or later in February – March 2010.
Retrieved from "http://soteria-space.eu/wiki/index.php/Deliverable_Template" Category: FirstAnnualReport
