Search Publications
Dynamics of Flare Processes and Variety of the Fine Structure of Solar Radio Emission over a Wide Frequency Range of 30 - 7000 MHz
Tan, Baolin; Tan, Chengming; Yan, Yihua +3 more
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 o…
Coronal Mass Ejections from the Same Active Region Cluster: Two Different Perspectives
Mandrini, C. H.; Schmieder, B.; Cremades, H. +1 more
The cluster formed by active regions (ARs) NOAA 11121 and 11123, approximately located on the solar central meridian on 11 November 2010, is of great scientific interest. This complex was the site of violent flux emergence and the source of a series of Earth-directed events on the same day. The onset of the events was nearly simultaneously observe…
The Relationship Between Solar Coronal X-Ray Brightness and Active Region Magnetic Fields: A Study Using High-Resolution Hinode Observations
Hazra, Soumitra; Nandy, Dibyendu; Ravindra, B.
By using high-resolution observations of nearly co-temporal and co-spatial Solar Optical Telescope spectropolarimeter and X-Ray Telescope coronal X-ray data onboard Hinode, we revisit the problematic relationship between global magnetic quantities and coronal X-ray brightness. Co-aligned vector magnetogram and X-ray data were used for this study. …
Detection of Solar Wind Disturbances: Mexican Array Radio Telescope IPS Observations at 140 MHz
Aguilar-Rodriguez, E.; Gonzalez-Esparza, J. A.; Romero-Hernandez, E. +2 more
The interplanetary scintillation (IPS) technique is a remote-sensing method for monitoring solar-wind perturbations. The Mexican Array Radio Telescope (MEXART) is a single-station instrument operating at 140 MHz, fully dedicated to performing solar-wind studies employing the IPS technique. We report MEXART solar-wind measurements (scintillation in…
An Interpretation of a Possible Mechanism for the First Ground-Level Enhancement of Solar Cycle 24
Gan, W. Q.; Rodríguez-Pacheco, J.; Li, Y. P. +1 more
It is well known that solar flares and shocks driven by coronal mass ejections (CMEs) are high-energy particle acceleration processes that might cause a high-energy particle event known as a ground-level enhancement (GLE). In this context, we have attempted to understand the processes responsible for the first GLE event (GLE71 17 May 2012 01:50 UT…
A Study of the Coronal Non-thermal Velocity in Polar Regions During the Rise from Solar Minimum to Solar Maximum in Cycle 24
van Driel-Gesztelyi, L.; Howe, R.; Harra, L. +3 more
We explore the changes in coronal non-thermal velocity (Vnt) measurements at the poles from solar minimum to solar maximum using Hinode EUV Imaging Spectrometer data. We find that although the intensity in the corona at the poles does tend to increase with the cycle, there are no significant changes in the Vnt values. The loc…
A Minimum Energy Fit Method to Reconstruct Photospheric Velocity and Magnetic Diffusivity in Active Regions from Observed Magnetograms and Dopplergrams
Tremblay, Benoit; Vincent, Alain
We introduce MEF-R, a generalization of the minimum energy fit (MEF; Longcope, Astrophys. J.612, 1181, 2004) to a non-ideal (resistive) gas. The new technique requires both vector magnetograms and Doppler velocities as input fields. However, in the case of active regions observed only with the Michelson-Doppler Imager (MDI) onboard the Solar and H…
Total Solar Irradiance Monitor for the FY-3B Satellite - Space Experiments and Primary Data Corrections
Wang, Hongrui; Li, Huiduan; Qi, Jin +1 more
We present space experiments of the Total Solar Irradiance Monitor (TSIM) on the FY-3B satellite. The total solar irradiance (TSI) has been measured by TSIM/FY-3B continuously for nearly four years, with some short data gaps. Overlapping measurements of the TSI are provided by the TSIM, with three electrical substitution radiometers that are mount…
Correlation Between CME Occurrence Rate and Current Helicity in the Global Magnetic Field of Solar Cycle 23
Zhang, Mei; Wang, Chuanyu
We investigate the correlation between the occurrence rate of the monthly coronal mass ejection (CME) and the magnitude of the current helicity in global magnetic field on the photosphere of solar cycle 23. We used the technique introduced by Pevtsov and Latushko (Astrophys. J. 528, 999, 2000) to retrieve the vector magnetic field from longitudina…
`Fingerprint' Fine Structure in the Solar Decametric Radio Spectrum Solar Physics
Konovalenko, A. A.; Melnik, V. N.; Dorovskyy, V. V. +2 more
We study a unique fine structure in the dynamic spectrum of the solar radio emission discovered by the UTR-2 radio telescope (Kharkiv, Ukraine) in the frequency band of 20 - 30 MHz. The structure was observed against the background of a broadband type IV radio burst and consisted of parallel drifting narrow bands of enhanced emission and absorptio…