Ellerman Bombs (EBs) are thought to arise as a result of photospheric magnetic reconnection. We use data from the Swedish 1-m Solar Telescope (SST), to study EB events on the solar disk and at the limb. Both datasets show that EBs are connected to the foot-points of forming chromospheric jets. The limb observations show that a bright structure in the H$α$ blue wing connects to the EB initially fuelling it, leading to the ejection of material upwards. The material moves along a loop structure where a newly formed jet is subsequently observed in the red wing of H$α$. In the disk dataset, an EB initiates a jet which propagates away from the apparent reconnection site within the EB flame. The EB then splits into two, with associated brightenings in the inter-granular lanes (IGLs). Micro-jets are then observed, extending to 500 km with a lifetime of a few minutes. Observed velocities of the micro-jets are approximately 5-10 km s$^{-1}$, while their chromospheric counterparts range from 50-80 km s$^{-1}$. MURaM simulations of quiet Sun reconnection show that micro-jets with similar properties to that of the observations follow the line of reconnection in the photosphere, with associated H$α$ brightening at the location of increased temperature.
H-alpha features with hot onsets. I. Ellerman bombs
埃勒曼炸弹是巴耳末线翅膀的短暂增亮，它独特地标志着太阳光球层的重联。它们在强的Ca II和紫外线以及紫外连续谱中也是明亮的，但它们在光学连续谱和Na I D和Mg I b线中不可见。这些不一致的活力使所有已发表的埃勒曼炸弹模型无效。我认为，假设的Saha-Boltzmann较低水平的人口是翔实的估计这些不同的诊断，甚至特别是H-α炸弹发病的不透明性，并采用这种估计来衡量在所有的埃勒曼炸弹发病的活力。它们将埃勒曼弹的形成限制在10，000 ~ 20，000 K的温度和10^15 cm^-3左右的氢密度。类似的论点可能适用于H-α可见性在其他瞬态现象与热和密集的开始。
Ellerman bombs at high resolution. IV. Visibility in Na I and Mg I
埃勒曼炸弹是太阳巴耳末线翅膀的短暂变亮，标志着光球层的重联。埃勒曼在1917年指出，他在Na I D和Mg I b谱线中没有观察到这种增亮。这种不可见性应限制EB解释，但尚未在已发表的炸弹模型中得到解决。因此，我们测试Ellerman的观察结果，并使用瑞典1米太阳望远镜的高质量成像光谱仪进行确认。然而，我们发现这些线中的漫射亮度似乎是由先前的EB引起的。我们初步认为，这是一个爆炸后的热云现象，也发现在最近的电子束光谱在紫外线。
Ellerman Bombs at high resolution: II. Visibility, triggering and effect on upper atmosphere
我们使用高分辨率成像光谱与瑞典1米太阳望远镜（SST）研究的瞬态增亮的翅膀的巴耳末Halalpha线在新兴的活跃地区，被称为埃勒曼炸弹。同时采样的钙II 854.2 nm的SST证实，大多数埃勒曼炸弹也发生在这条线的翅膀，但有显着不同的形态。来自太阳动力学天文台（SDO）的同步图像显示，埃勒曼炸弹也可以在光球170 nm连续谱中检测到，同样具有不同的形态。它们也可以在160 nm SDO图像中观察到，但在过渡区特征中有很多来自C IV发射的污染。同时SST光谱偏振在Fe I 630.1 nm表明，埃勒曼炸弹发生在网站的强场磁通量小双极强场补丁之间的抵消，迅速移动到一起在太阳表面。在He II 30.4 nm，Fe IX 17.1 nm和Fe XIV 21.1 nm的同时SDO图像显示，Ellerman炸弹对上覆过渡区和日冕没有明显的影响。这些结果加强了我们先前的建议，根据单独的H α形态，埃勒曼炸弹现象是一个纯粹的光球重联现象。
Ellerman bombs are regions with enhanced Balmer line wing emission and mark magnetic reconnection in the deep solar atmosphere in active regions and quiet Sun. They are often found in regions where opposite magnetic polarities are in close proximity. Recent high resolution observations suggest that Ellerman bombs are more prevalent than thought before. We aim to determine the occurrence of Ellerman bombs in the penumbra of sunspots. We analyze high spatial resolution observations of sunspots in the Balmer H-alpha and H-beta lines as well as auxiliary continuum channels obtained with the Swedis…
Solar Ellerman Bombs in 1-D Radiative Hydrodynamics
最近的观测从接口区域成像光谱仪（IRIS）似乎显示脉冲增亮高温线，这与同时在H $α$地面观测相结合时，出现同空间的埃勒曼炸弹（EBs）。我们使用的RADYN一维辐射转移代码，试图重现所观察到的线轮廓和模拟这些事件的大气条件。结合MULTI/RH谱线合成程序，我们计算了这些模拟事例的H $α$、Ca Ⅱ 8542~ K和Mg Ⅱ h \& k谱线，并与以前的观测结果进行了比较。我们的研究结果暗示，光球层（$>$ 10，000 K）中过热区域的存在并不是EB信号产生的合理解释。虽然我们能够在H $α$、Ca II 8542~+和Mg II h \& k中重建EB样线轮廓，但我们不能同时与所有这些一致。
Ellerman bombs (EBs) and UV bursts are both small-scale solar activities that occur in active regions. They are now believed to form at different heights in the lower atmosphere. In this paper, we use one-dimensional radiative hydrodynamic simulations to calculate various line profiles in response to heating in different atmospheric layers. We confirm that heating in the upper photosphere to the lower chromosphere can generate spectral features of typical EBs, while heating in the mid to upper chromosphere can generate spectral features of typical UV bursts. The intensity evolution of the H$α$…
Ellerman bombs (EBs) and Ultraviolet (UV) bursts are common brightening phenomena which are usually generated in the low solar atmosphere of emerging flux regions. In this paper, we have investigated the emergence of an initial un-twisted magnetic flux rope based on three-dimensional (3D) magneto-hydrodynamic (MHD) simulations. The EB-like and UV burst-like activities successively appear in the U-shaped part of the undulating magnetic fields triggered by Parker Instability. The EB-like activity starts to appear earlier and lasts for about 80 seconds. Six minutes later, a much hotter UV burst-l…
The focus of this investigation is to quantify the conversion of magnetic to thermal energy initiated by a quiet Sun cancellation event and to explore the resulting dynamics from the interaction of the opposite polarity magnetic features. We used imaging spectroscopy in the H$α$ line, along with spectropolarimetry in the \ion{Fe}{I} 6173~Å and \ion{Ca}{II} 8542~Å lines from the Swedish Solar Telescope (SST) to study a reconnection-related cancellation and the appearance of a quiet Sun Ellerman bomb (QSEB). We observed, for the first time, QSEB signature in both the wings and core of the \ion{F…
Observations of Ellerman bomb emission features in He I D3 and He I 10830 Å
上下文埃勒曼炸弹（EB）是短寿命的发射功能，其特点是延长翼发射的氢巴耳末线。到目前为止，在He I 10830线上还没有发现明显的EB信号，在He I D3中也没有发现EB的结论性观测。目的。我们的目标是研究中性氦三重线中电子束的特征。方法.观测包括10个连续的SST/TRIPPEL光栅扫描接近临边，具有H $β$，He I D3和He I 10830的光谱区域。我们还获得了光栅扫描与IRIS和使用SDO/AIA 1700的可编程逻辑器件通道。我们用Hazel来反转中性氦三重态线。结果我们的数据中的三个EB在中性氦三重态线中显示出不同的发射特征，最显著的是在He I D3线中可见。氦谱线有两个组成部分：一个是与电子束相关的宽的蓝移发射分量，另一个是在上覆色球层中形成的窄吸收分量。在我们的数据中，其中一个EB在其发射分量中显示出强速度梯度的证据。其他两个EB的发射分量可以使用恒定板来拟合。我们的分析提示热多普勒运动有很大的贡献氦和IRIS线的加宽。我们的结论是，电子束必须有高温表现出中性氦三重线的发射信号。一个数量级的估计将我们观察到的EB置于$T\sim 2\cdot 10^4-10^5$ K的范围内。
Ellerman bombs and UV bursts: transient events in chromospheric current sheets
埃勒曼炸弹（EB）和紫外线爆发都是与通量出现区域有关的增亮，特别是与在光球中相遇的相反极性的磁通量有关。这两个与重连有关的现象，名义上形成的距离很远，偶尔会发生在同一地点和同一时间，从而挑战了我们对重连和太阳低层大气加热的理解。我们认为，形成一个活跃的地区，包括长纤维和热，致密的日冕等离子体。本文研究了光球层下注入$2.5$ ~Mm的无扭曲磁通量片穿透光球层并与已存在的环境场相互作用的过程。具体来说，我们的目标是研究是否EB和紫外线爆发产生的结果，这种通量的出现，并检查它们的物理关系。彩虹辐射磁流体动力学代码被用来模拟通量出现在一个模型大气中，其中包含一个相当强的环境场，约束新兴的领域，以有限的体积，其中多个重联事件发生的领域突破光球，并扩大到外层大气。使用$1.5$ D RH代码和全三维MULTI 3D代码计算不同重联事件的合成谱。紫外线爆发和电子束的形成强度和线轮廓与观察到的光谱非常相似，这被认为是新兴通量与其自身在一个持久的电流片中重新连接的结果，该电流片在色球层中延伸了几个标度高度。合成诊断表明，没有令人信服的理由假设光球中发生紫外线爆发。相反，EB和紫外线爆发偶尔会在长电流片的两端形成，该电流片位于冷气体的延伸气泡中。
Shock-induced magnetic reconnection driving Ellerman bomb emission and a spicule
University of Oslo（奥斯陆大学）；Sorbonne Université, Observatoire de Paris – PSL, École Polytechnique, Institut Polytechnique de Paris, CNRS, Laboratoire de Physique des Plasmas (LPP)（索邦大学、巴黎天文台-PSL、巴黎综合理工学院、巴黎理工学院、法国国家科学研究中心等离子体物理实验室）；SETI Institute（SETI研究所）；Lockheed Martin Solar and Astrophysics Laboratory（洛克希德·马丁太阳与天体物理学实验室）
Magnetic reconnection in the deep solar atmosphere can give rise to enhanced emission in the Balmer hydrogen lines, a phenomenon referred to as Ellerman bombs. Recent high quality H$β$ observations indicate that Ellerman bombs are more common than previously thought and it was estimated that at any time about half a million Ellerman bombs are present in the quiet Sun. We performed an extensive statistical characterization of the quiet Sun Ellerman bombs (QSEBs) in these new H$β$ observations. We analyzed a 1 h dataset of quiet Sun observed with the Swedish 1-m Solar Telescope that consists of …
Three-dimensional Magnetic Structures of Ellerman Bombs revealed by SUNRISE III/SCIP
National Astronomical Observatory of Japan（日本国立天文台）；Department of Astronomy, The University of Tokyo（东京大学天文学系）；Department of Astronomical Science, The Graduate University for Advanced Studies (SOKENDAI)（advanced studies 高级研究大学院大学天体科学系）；Advanced Research Center for Space Science and Technology, Institute of Science and Engineering, Kanazawa University（金泽大学理工学研究科宇宙科学技术高级研究中心）；Max-Planck-Institut für Sonnensystemforschung（马克斯·普朗克太阳系统研究所）；Centre for Integrated Data Science, Institute for Space-Earth Environmental Research, Nagoya University（名古屋大学地球环境空间研究所综合数据科学中心）；National Institute for Fusion Science（日本核融合科学研究所）
IRIS Burst Spectra Co-Spatial To A Quiet-Sun Ellerman-Like Brightening
埃勒曼炸弹（EB）在过去的二十年里得到了广泛的研究;然而，直到最近才在安静的太阳中观察到这些事件的对应物。本文的目的是进一步了解小规模的安静太阳Ellerman样增亮（QSEBs）通过研究他们的光谱特征，包括调查是否与一些EB相关的热签名也是可见的任何QSEBs的空间。我们结合H $α$和Ca II $8542$在太阳边缘的光谱和成像数据采样的接口区域成像光谱仪（IRIS）。鉴定出21个QSEB，其平均寿命、长度和宽度分别测量为大约$120$“、$0.63$“和$0.35$“。其中三个QSEBs显示出明确的重复燃烧，通过他们的生命周期，在活动区（AR）的EB的行为。在SDO/AIA $1600$和IRIS裂隙颌成像仪$1400$的数据中，该样本中的两个QSEB与发射增加共空间发生，然而，这些强度增加小于与EB共空间报告的强度增加。一个QSEB在其寿命期间也被IRIS狭缝取样，显示Si IV $1393$和Si IV $1403$核心以及C II和Mg II线翼的强度增加，类似于IRIS爆发（IB）。使用RADYN模拟，我们无法重现所观察到的QSEB H $α$和钙II $8542$的轮廓线离开QSEB的温度分层的问题开放。我们的研究结果表明，一些QSEBs可以加热到过渡区的温度，这表明IB配置文件应在整个安静的太阳。
Repeated Sunspot Light Bridge Jets Associated with Slipping Base Brightenings
Yunnan Observatories, Chinese Academy of Sciences（中国科学院云南天文台）；Yunnan Key Laboratory of Solar Physics and Space Science（云南省太阳物理与空间科学重点实验室）；School of Earth and Space Sciences, Peking University（北京大学地球与空间科学学院）；Centre for Mathematical Plasma Astrophysics, Department of Mathematics, KU Leuven（荷语鲁汶大学数学系数学等离子体天体物理中心）
Ellerman Bomb-like brightenings of the hydrogen Balmer line wings in the quiet Sun (QSEBs) are a signature of the fundamental process of magnetic reconnection at the smallest observable scale in the solar lower atmosphere. We analyze high spatial resolution observations (0.1 arcsec) obtained with the Swedish 1-m Solar Telescope to explore signatures of QSEBs in the H$β$ line. We find that QSEBs are ubiquitous and uniformly distributed throughout the quiet Sun, predominantly occurring in intergranular lanes. We find up to 120 QSEBs in the FOV for a single moment in time; this is more than an or…
Ultraviolet (UV) bursts and Ellerman bombs (EBs) are small-scale magnetic reconnection events taking place in the highly stratified, low solar atmosphere. It is still not clear whether UV bursts have to be generated at a higher atmospheric layer than EBs or whether both UV bursts and EBs can occur in the low chromosphere. We numerically studied the low $β$ magnetic reconnection process around the solar temperature minimum region (TMR). The time-dependent ionization degrees of hydrogen and helium are included in the MHD code, which lead to a more realistic magnetic diffusion caused by electron-…
UV bursts and Ellerman bombs are transient brightenings observed in the low solar atmospheres of emerging flux regions. Observations have discovered the cospatial and cotemporal EBs and UV bursts, and their formation mechanisms are still not clear. The multi-thermal components with a large temperature span in these events challenge our understanding of magnetic reconnection and heating mechanisms in the low solar atmosphere. We have studied magnetic reconnection between the emerging and background magnetic fields. The initial plasma parameters are based on the C7 atmosphere model. After the cu…
