Results 31 to 40 of about 112,475 (200)
New classification parameter of solar flares based on the maximum flux in soft X-rays and on duration of flare [PDF]
, 2018 Solar flare activity is characterised by different classification systems, both in optical and X-ray ranges. The most generally accepted classifications of solar flares describe important parameters of flares such as the maximum of brightness of the flare in the in optical range - $H_{\alpha}$ flare class (change from F to B), area of the flare in $H_{\
arxiv +1 more source
The Influence of Solar Spectral Lines on Electron Concentration in Terrestrial Ionosphere
Open Astronomy, 2011 One of the methods of detection and analysis of solar flares is observing the time variations of certain solar spectral lines. During solar flares, a raise of electron concentration occurs in Earth’s ionosphere which results in amplitude and phase ...
Nina A. +3 more
doaj +1 more source
The Efficiency of Electron Acceleration during the Impulsive Phase of a Solar Flare
The Astrophysical Journal Letters, 2023 Solar flares are known to be prolific electron accelerators, yet identifying the mechanism(s) for such efficient electron acceleration in solar flare (and similar astrophysical settings) presents a major challenge.
Eduard P. Kontar +3 more
doaj +1 more source
Conditions for arrival of solar energetic protons in Earth after strong solar flares
Solar-Terrestrial Physics, 2022 We analyze the Sun-to-Earth transport of energetic protons accelerated in solar flares. We use a model which assumes that protons move earthward in the Parker electromagnetic field.
Kichigin G. N. +2 more
doaj +1 more source
Short Duration Stellar Flares in GALEX Data [PDF]
, 2019 We report on a population of short duration near-ultraviolet (NUV) flares in stars observed by the Kepler and GALEX missions. We analyzed NUV light curves of 34,276 stars observed from 2009-2013 by both the GALEX (NUV) and Kepler (optical) space missions with the eventual goal of investigating multi-wavelength flares. From the GALEX data we constructed
arxiv +1 more source
Alternative Waiting Time Statistics for the Lu and Hamilton Avalanche Model
The Astrophysical Journal, 2023 The solar corona hosts many explosive events. Among them, flares are some of the most energetic, rapidly releasing huge amounts of energy and, in the case of the largest ones, producing coronal mass ejections that have the potential to harm life on our ...
Matías Kychenthal, Laura F. Morales
doaj +1 more source
Gamma-Ray Polarimetry of Two X-Class Solar Flares [PDF]
Astrophys.J.638:1129-1139,2006, 2005 We have performed the first polarimetry of solar flare emission at gamma-ray energies (0.2-1 MeV). These observations were performed with the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) for two large flares: the GOES X4.8-class solar flare of 2002 July 23, and the X17-class flare of 2003 October 28.
arxiv +1 more source
Scaling laws of solar and stellar flares [PDF]
, 2007 In this study we compile for the first time comprehensive data sets of solar and stellar flare parameters, including flare peak temperatures T_p, flare peak volume emission measures EM_p, and flare durations t_f from both solar and stellar data, as well as flare length scales L from solar data.
arxiv +1 more source
Insights Into the Light‐Driven Conversion of Methane: Mechanisms, Characterization, and Perspective
EcoEnergy, EarlyView.Methane can be converted into value‐added products, offering a sustainable and economically viable approach to energy and carbon use. Photocatalytic methane conversion under mild conditions is an effective method for activating methane. This review outlines key mechanisms for C–H bond activation, categorizes products from methane conversion, and ...
Jiayi Chen +3 more
wiley +1 more source
The Astrophysical Journal, 2023 We often find spectral signatures of chromospheric cold plasma ejections accompanied by flares in a wide range of spatial scales in the solar and stellar atmospheres.
Yuji Kotani +6 more
doaj +1 more source