Research on the quantity and brightness evolution characteristics of Photospheric Bright Points groups
HaiCheng Bai
备注:
The paper was edited using the Latex template from Astronomy & Astrophysics, but this paper has never been published publicly in Astronomy & Astrophysics. This mistake is very misleading. At the same time, there are some errors in the description of the experimental data in the original paper, and the experimental content is also insufficient
Context. Photospheric bright points (BPs), as the smallest magnetic element of the photosphere and the footpoint tracer of the magnetic flux tube, are of great significance to the study of BPs. Compared with the study of the characteristics and evolution of a few specific BPs, the study of BPs groups can provide us with a better understanding of the characteristics and overall activities of BPs groups. Aims. We aim to find out the evolution characteristics of the brightness and number of BPs groups at different brightness levels, and how these characteristics differ between quiet and active regions. Methods. We propose a hybrid BPs detection model (HBD Model) combining traditional technology and neural network. The Model is used to detect and calculate the BPs brightness characteristics of each frame of continuous high resolution image sequences of active and quiet regions in TiO-band of a pair of BBSO. Using machine learning clustering method, the PBs of each frame was divided into four levels groups (level1-level4) according to the brightness from low to high. Finally, Fourier transform and inverse Fourier transform are used to analyze the evolution of BPs brightness and quantity in these four levels groups. Results. The activities of BPs groups are not random and disorderly. In different levels of brightness, their quantity and brightness evolution show complex changes. Among the four levels of brightness, BPs in the active region were more active and intense than those in the quiet region. However, the quantity and brightness evolution of BPs groups in the quiet region showed the characteristics of large periodic changes and small periodic changes in the medium and high brightness levels (level3 and level4). The brightness evolution of PBs group in the quiet region has obvious periodic changes, but the active region is in a completely random and violent fluctuation state.
The relationship between chromospheric emissions and magnetic field strength
目标。分析了4台仪器的观测资料,研究了从温度最低区到色球中层高度的色球辐射与光球磁场的相关性。研究方法:数据包括伯克利-伊利诺伊-马里兰阵列(BIMA)的3.5 mm射电图像,TRACE的1600 A紫外图像,BBSO的Ca II K线滤波图和MDI/SOHO纵向光球磁图。第一次干涉毫米数据与目前最高的可用分辨率包括在这样的分析。我们确定强度图的各种参数,并将强度彼此关联并与磁场关联。结果如下:这里研究的色球诊断显示出它们的亮度结构有明显的相似性,并相对较好地绘制出了底层的光球磁场。我们发现一个幂律是一个很好的光球磁场和色球诊断在所有波长的发射之间的关系表示。色球亮度对磁场的依赖性在网络区和网络间区是不同的。
SN2023ixf: Radiative-transfer modeling of the photospheric phase evolution from the ultraviolet to the infrared
Institut d’Astrophysique de Paris, CNRS-Sorbonne Université(巴黎天体物理学研究所,法国国家科学研究中心-索邦大学);French-Chilean Laboratory for Astronomy, IRL 3386, CNRS and Instituto de Astrofísica, Pontificia Universidad Católica de Chile(中法天文实验室,法国国家科学研究中心与智利天主教庞蒂菲亚大学天体物理研究所);Cahill Center for Astrophysics, California Institute of Technology(加州理工学院卡希尔天体物理学中心);Steward Observatory, University of Arizona(亚利桑那大学斯图尔德天文台);Department of Astronomy, University of California, Berkeley(加州大学伯克利分校天文学系);Department of Physics and Astronomy, University of California, Davis(加州大学戴维斯分校物理与天文学系)
Seismological determination of the Alfvén speed and plasma-beta in solar photospheric bright points
对\textit{Hinode}卫星上太阳光学望远镜的宽带滤波成像仪观测到的光球亮点中的阿尔文速度和等离子体β进行了地震学估算。诊断是基于慢磁声波在一个非等温分层光球均匀垂直磁场的理论。我们使用3D区域生长方法识别和跟踪G波段电影中的亮点,并将它们与蓝色连续图像对齐,以获得它们的亮度温度。从118个亮点的连续光变曲线的傅立叶功率谱中,我们发现91个亮点的光变曲线具有明显不同于平静区的振荡特性,周期在2.2- 16.2 min之间。我们发现,当$γ$位于5/3附近时,模型给出了中等的等离子体β值。计算得到的阿尔文速度为9.68 $\pm$ 2.02 km s $^{-1}$,范围为6.3- 17.4 km s $^{-1}$。血浆β估计为0.93 $\pm$ 0.36,范围为0.2- 1.9。
What Determines the Brightness of the Magnetically Open Solar Corona?: Insights from Three-dimensional Radiative Magnetohydrodynamic Simulations and Observations
Institute for Space-Earth Environmental Research, Nagoya University(名古屋大学宇宙地球环境研究所);Institute for Advanced Research, Nagoya University(名古屋大学高等研究院)
Dynamics of the solar magnetic bright points derived from their horizontal motions
与太阳低层大气小尺度磁场有关的亚弧秒亮点(BP)是由光球颗粒演化平流产生的。我们测量了在两个波长上观测到的与BPs水平运动有关的各种量,包括速度自相关函数。在\textit{Swedish 1-m Solar Telescope}(\textit{SST})进行的宽带H $α$观测的1小时时间序列,和与太阳光学望远镜观测的4小时\textit{Hinode} \textit{G} -波段时间序列在这项工作中使用。我们跟踪了97例\textit{SST}和212例\textit{Hinode} BP,分别测量了3800和1950个个体速度。与\textit{Hinode}数据的30 s相比,其5 s的高节奏,我们更强调来自\textit{SST}数据的结果。由\textit{SST}实现的BP位置不确定性低至3 km。位置误差对观测速度方差的贡献为0.75 km $^2$ s $^{-2}$。两个方向上的\textit{raw}和\textit{corrected}速度测量,即,$(v_x,v_y)$具有高斯分布,其标准偏差分别为$(1.32,1.22)$和$(1.00, 0.86)$ km s $^{-1}$。BP运动的相关时间约为$22 - 30$ s。我们构建的水平运动的功率谱作为频率的函数,一个量,这是有用的和相关的生成的阿尔文波的研究。光球湍流扩散在小于200秒的时间尺度被…
Structure and Dynamics of Isolated Internetwork Ca II H Bright Points Observed by Sunrise
我们的目标是改善我们的图片在安静的太阳互联网的低色球层通过调查的强度,水平速度,大小和寿命的变化小亮点(BPs;直径小于0.3弧秒)观察到的Ca II H 3968通带沿其磁场参数,来自光球磁图。对从太阳表面空间分辨率约为100公里的“日出”球载太阳望远镜获得的盘心静日观测的若干高质量时间序列进行了分析,以研究在Ca II H通带观测到的BPs动态及其对光球矢量磁图信号的依赖性。参数,如水平速度,直径,强度和寿命直方图的孤立的互联网和磁性钙II H BP。平均值分别为2.2 km/s、0.2 arcsec(150 km)、1.48平均Ca II H宁静太阳和673 sec。有趣的是,BPs的亮度和水平速度是反相关的。大偏移(脉冲)的水平速度,高达15公里/秒,目前在大多数BP的轨迹。这可能激发出进入色球层甚至日冕的扭折波,我们估计扭折波携带的能量通量为310 W/m^2,足以加热上层,尽管只是少量的。稳定的观测条件的日出和我们的技术,用于识别和跟踪BP,使我们能够确定可靠的参数,这些功能在互联网。因此,我们发现,例如,它们的寿命比我们之前认为的要长得多大的速度也是可靠的,并可能激发扭结波。虽然这些波(勉强)能量足以加热安静的日冕,但我们预计来自网络中较大的磁性元素以及部分互联网络的大量额外贡献。
Characteristics of Chromospheric Oscillation Periods in Magnetic Bright Points (MBPs)
在这项调查中,振荡周期的Mg II K线强度,亮度温度和多普勒速度以上获得的磁亮点(MBPs)的影响。为此目的,对观测高层色球层和过渡区的界面区成像光谱仪的数据以及太阳动力学观测站获得的成像和磁图数据进行了分析。在结合Si IV 1403 A狭缝钳口图像(SJI)与来自日光层和磁成像仪(HMI)的磁图信息中识别MBPs。对Mg II k(2796 A和10,000 K)共振线进行时间片分析,然后进行小波检查,以检测振荡周期。最后,对振荡进行了功率谱分析,结果表明,网络点具有典型的强度、温度和速度振荡周期约为300 s,网络间点的平均强度振荡周期约为180 s,平均温度振荡周期约为202 s,平均速度振荡周期约为202 s.此外,对一个BP进行了详细分析,它表明强度振荡周期为500秒,显然与色球/光球结构中通常在其他地方发现的3或5分钟振荡无关。