The Atmospheric Response to High Nonthermal Electron-beam Fluxes in Solar Flares. II. Hydrogen-broadening Predictions for Solar Flare Observations with the Daniel K. Inouye Solar Telescope
The Atmospheric Response to High Nonthermal Electron-beam Fluxes in Solar Flares. II. Hydrogen-broadening Predictions for Solar Flare Observations with the Daniel K. Inouye Solar Telescope
复制标题
DOI：
10.3847/1538-4357/ac5174
复制
发表时间：
2022-01
期刊：
影响因子：
--
通讯作者：
A. Kowalski;J. Allred;M. Carlsson;G. Kerr;P. Tremblay;K. Namekata;D. Kuridze;H. Uitenbroek
中科院分区：
文献类型：
--
作者：
A. Kowalski;J. Allred;M. Carlsson;G. Kerr;P. Tremblay;K. Namekata;D. Kuridze;H. Uitenbroek
利用高分辨率的界面区成像光谱仪研究了耀斑硬X射线脉冲相色球发射谱线30 s的红移分量。辐射流体动力学耀斑模型表明，这些红移一般是由电子束产生的色球凝聚再现。该模型产生大的环境电子密度，和压力加宽的氢巴耳末系列应很容易检测到的意见。为了准确地解释即将到来的光谱数据的耀斑与DKIST，我们将非理想的，非绝热线加宽的氢到RADYN代码的配置文件。这些改进允许随时间变化的预测极端巴耳末线翼增强太阳耀斑。我们研究了两个色球凝聚模型，它们涵盖了耀斑色球中电子束通量（1 - 5 × 1011 erg s-1 cm-2）和环境电子密度（1 - 60 × 1013 cm-3）的范围。这两种模型产生的光束加热的发病10秒内的加宽和红移的变化。在色球凝聚中，由于Hα、Hβ和Hγ处的光学深度较大，光谱增宽增强，而巴耳末系列H12−H16的光学深度要低得多，为凝聚下方的束流加热层中较小的电子密度提供了一个半透明的窗口。太阳耀斑的典型DKIST/ViSP光谱的波长范围将足以测试极端氢翼加宽的预测，并准确地限制色球凝聚的大密度。
Redshifted components of chromospheric emission lines in the hard X-ray impulsive phase of solar flares have recently been studied through their 30 s evolution with the high resolution of the Interface Region Imaging Spectrograph. Radiative-hydrodynamic flare models show that these redshifts are generally reproduced by electron-beam-generated chromospheric condensations. The models produce large ambient electron densities, and the pressure broadening of the hydrogen Balmer series should be readily detected in observations. To accurately interpret the upcoming spectral data of flares with the DKIST, we incorporate nonideal, nonadiabatic line-broadening profiles of hydrogen into the RADYN code. These improvements allow time-dependent predictions for the extreme Balmer line wing enhancements in solar flares. We study two chromospheric condensation models, which cover a range of electron-beam fluxes (1 − 5 × 1011 erg s−1 cm−2) and ambient electron densities (1 − 60 × 1013 cm−3) in the flare chromosphere. Both models produce broadening and redshift variations within 10 s of the onset of beam heating. In the chromospheric condensations, there is enhanced spectral broadening due to large optical depths at Hα, Hβ, and Hγ, while the much lower optical depth of the Balmer series H12−H16 provides a translucent window into the smaller electron densities in the beam-heated layers below the condensation. The wavelength ranges of typical DKIST/ViSP spectra of solar flares will be sufficient to test the predictions of extreme hydrogen wing broadening and accurately constrain large densities in chromospheric condensations.