We present a statistical study of 106 filament eruptions, which were automatically detected by pattern recognition program implemented at Big Bear Solar Observatory using Hα full-disk data from 1999 to 2003. compare these events with Geostationary Operational Environmental Satellite soft X-ray time profiles, solar-geophysical (SGD) solar event reports, Michelson Doppler Imager magnetograms, and Large Angle Spectrometric Coronagraph (LASCO) determine the relationship between eruptions other...

We present a new method for automatically forecasting the occurrence of solar flares based on photospheric magnetic measurements. The is cascading combination an ordinal logistic regression model and support vector machine classifier. predictive variables are three parameters, i.e., total unsigned flux, length strong-gradient polarity inversion line, energy dissipation. output true or false certain level within 24 hours. Experimental results, from sample 230 active regions between 1996 2005,...

The rapid, irreversible change of the photospheric magnetic field has been recognized as an important element solar flare process. This Letter reports such a rapid fields during 2011 February 13 M6.6 in NOAA AR 11158 that we found from vector magnetograms Helioseismic and Magnetic Imager (HMI) with 12 minute cadence. High-resolution Hinode are available at ∼−5.5, −1.5, 1.5, 4 hr relative to maximum used reconstruct three-dimensional coronal under nonlinear force-free (NLFFF) assumption. UV...

In this paper, we present a detailed study of two-ribbon flare in the plage region observed by Kanzelhohe Solar Observatory (KSO), which is one stations our global Hα network. We select event due to its very clear filament eruption, separation, and association with fast coronal mass ejection (CME). separation between two ribbons seen as function time find that motion consisted stage rapid at speed about 15 km s-1 first 20 minutes slow 1 lasting for 2 hr. then estimate rate magnetic...

A type of mass motion in solar filaments, not previously reported, is studied with high-cadence (1 minute) Hα observations made at the Big Bear Solar Observatory on 2001 October 24. This oscillatory along filament and extends over a long distance (~1.4 × 105 km) period ~80 minutes very high velocity amplitude ~92 km s-1. Another significant property this oscillation that it triggered by subflare occurred near its footpoint. The completes three cycles before damps out timescale ~210 minutes....

Both magnetic and current helicities are crucial ingredients for describing the complexity of active-region structure. In this Letter, we present temporal evolution these contained in NOAA active region 11158 during five days from 2011 February 12 to 16. The photospheric vector magnetograms Helioseismic Magnetic Imager on board Solar Dynamic Observatory were used as boundary conditions coronal field extrapolation under assumption nonlinear force-free field, which calculated both relative...

Abstract In this study we synthesize the results of four previous studies on global energetics solar flares and associated coronal mass ejections (CMEs), which include magnetic, thermal, nonthermal, CME energies in 399 M- X-class flare events observed during first 3.5 yr Solar Dynamics Observatory ( SDO ) mission. Our findings are as follows. (1) The sum mean nonthermal energy flare-accelerated particles <?CDATA ${E}_{\mathrm{nt}}$?> ), direct heating ${E}_{\mathrm{dir}}$?> CMEs...

A recent laboratory experiment of ideal magnetohydrodynamic (MHD) instabilities reveals four distinct eruption regimes readily distinguished by the torus instability (TI) and helical kink (KI) parameters \citep{Myers2015}. To establish its observational counterpart, we collect 38 solar flares (stronger than GOES class M5 in general) that took place within 45$^{\circ}$ disk center during 2011$-$2017, 26 which are associated with a halo or partial coronal mass ejection (CME) (i.e., ejective...

Solar flares signify the sudden release of magnetic energy and are sources so called space weather. The fine structures (below 500 km) rarely observed accessible to only a few instruments world-wide. Here we present observation solar flare using exceptionally high resolution images from 1.6~m New Telescope (NST) equipped with order adaptive optics at Big Bear Observatory (BBSO). reveals process in unprecedented detail, including ribbon propagating across sunspots, coronal rain (made...

The application of machine learning to the study coronal mass ejections (CMEs) and their impacts on Earth has seen significant growth recently. Understanding forecasting CME geoeffectiveness is crucial for protecting infrastructure in space ensuring resilience technological systems Earth. Here we present GeoCME, a deep-learning framework designed predict, deterministically or probabilistically, whether event that arrives at will cause geomagnetic storm. A storm defined as disturbance Earth's...

Abstract The dynamic structures of solar filaments prior to flares provide important physical clues about the onset eruptions. Observations those under subarcsecond resolution with high cadence are rare. We present high-resolution observations covering preeruptive and eruptive phases two C-class flares, C5.1 (SOL2022-11-14T17:29) (SOL2022-11-14T19:29), obtained by Goode Solar Telescope at Big Bear Observatory. Both ejective, i.e., accompanied coronal mass ejections (CMEs). High-resolution H...

Abstract We present a transformer model, named DeepHalo, to predict the occurrence of halo coronal mass ejections (CMEs). Our model takes as input an active region (AR) and profile, where profile contains time series data samples in AR that are collected 24 hr before beginning day, predicts whether would produce CME during day. Each sample physical parameters, or features, derived from photospheric vector magnetic field taken by Helioseismic Magnetic Imager on board Solar Dynamics...

Forbes & Lin derived simple equations to link the properties of magnetic reconnection in corona observed signatures solar flares. We measured photospheric fields and flare ribbon separation speeds then applied these derive two physical terms for rates: rate flux change φrec involved low electric field Erec inside reconnecting current sheet (RCS) that is generated during reconnection. The central interest this work investigate quantify statistical correlation between corresponding flux-rope...

We observed two X-class white-light flares (WLFs) on 2003 October 29 (~20:40 UT) and November 2 (~17:16 using the Dunn Solar Telescope (DST) its High-Order Adaptive Optics (HOAO) system in several wavelengths. The spatial resolution was close to diffraction limit of DST's 76 cm aperture, cadence as high s. This is first time that WLFs have been near-infrared (NIR) wavelength region. present a detailed study this paper comparing photospheric continuum observations during events with...

Using line-of-sight Michelson Doppler Imager (MDI) magnetograms of 89 active regions and Solar Geophysical Data (SGD) flare reports, we explored, for the first time, magnitude scaling correlations between three parameters magnetic fields productivity solar regions. These are (1) mean value spatial gradients at strong-gradient neutral lines, ()NL; (2) length LGNL; (3) total energy, (Bz) dA, dissipated in a layer 1 m during s over region's area. The MDI used our analysis close to central...

In this study, the photospheric vector magnetograms, obtained with Spectro-Polarimeter of Solar Optical Telescope on board Hinode, are used as boundary conditions to extrapolate three-dimensional nonlinear force-free (NLFF) coronal magnetic fields. The observed non-force-free fields preprocessed toward nearly chromospheric performance preprocessing procedure is evaluated by comparing Vector SpectroMagnetograph instrument located Synoptic Long-term Investigations Sun Tower. Then, weighted...

We present the first interferometric observation of a zebra-pattern radio burst with simultaneous high spectral (≈1 MHz) and time (20 ms) resolution. The Frequency-Agile Solar Radiotelescope Subsystem Testbed (FST) Owens Valley Array (OVSA) were used in parallel to observe X1.5 flare on 2006 December 14. By using OVSA calibrate FST, source position zebra pattern can be located solar disk. With help multi-wavelength observations nonlinear force-free field extrapolation, is explored relation...

We present the first part of a project on global energetics solar flares and coronal mass ejections (CMEs) that includes about 400 M- X-class observed with AIA HMI onboard SDO. calculate potential energy, free flare-dissipated magnetic energy. these parameters using two different NLFFF codes: The COR-NLFFF code uses line-of-sight field component $B_z$ from to define field, 2D coordinates automatically detected loops in 6 wavelengths measure helical twist caused by vertical currents, while...

This Letter reports two rarely observed three-ribbon flares (M1.9 and C9.2) on 2012 July 6 in NOAA AR 11515, which we found with Halpha observations of 0.1" resolution from the New Solar Telescope CaII H images Hinode. The flaring site is characterized an intriguing "fish-bone-like" morphology evidenced by both a nonlinear force-free field (NLFFF) extrapolation, where semi-parallel rows low-lying, sheared loops connect elongated, parasitic negative sandwiching positive fields. NLFFF model...

Sunspots are concentrations of magnetic field visible on the solar surface (photosphere). It was considered implausible that flares, as resulted from reconnection in tenuous corona, would cause a direct perturbation dense photosphere involving bulk motion. Here we report sudden flare-induced rotation sunspot using unprecedented spatiotemporal resolution 1.6 m New Solar Telescope, supplemented by data Dynamics Observatory. is clearly observed non-uniform over sunspot: flare ribbon sweeps...