Subsurface magnetic reconnection, with its location changing with the depth of the plasma region in the chromosphere (from photosphere to corona), has been observed on the Sun. The authors explored the subsurface structure of active region AR 11504 by analysing the emission lines and their density and temperature dependence.

The figures taken from the work of Deborah Baker and coauthors show the white light continuum images from Hinode’s EUV Imaging Spectrometer, for different days (left panel —14 June 2012 at 00:58 UT and right panel — 15 June 2012 at 00:58 UT). The strength and direction of the horizontal magnetic field is indicated by the arrows. One can see the location of the light bridges in both figures, left panel (around X = −147′′, Y = −292′′), right panel (around X = 64′′, Y = −299′′). The horizontal magnetic field in the light bridge is about 200 G while in the surrounding regions it is up to 1,500 G. These fields are strong enough to produce the I-FIP effect which is supported from the further analysis of the plasma parameters (for example — density and wave amplitude). Overall, these are signatures of episodic heating and reconnection outflows in regions between magnetic flux tubes forming a light bridge and it can be concluded that light bridges are likely locations of the magnetic reconnection.

在太阳上观察到了地下磁重联，其位置随着色球层等离子体区域（从光球层到日冕）的深度而变化。作者通过分析发射线及其密度和温度依赖性，探索了活性区 AR 11504 的地下结构。

Deborah Baker 及其合著者的作品中的数据显示了 Hinode 的 EUV 成像光谱仪在不同日期拍摄的白光连续图像（左图 — 2012 年 6 月 14 日 00:58 UT，右图 — 2012 年 6 月 15 日 00:58 UT） ）。水平磁场的强度和方向由箭头指示。人们可以在两张图中看到光桥的位置，左图（X = -147”，Y = -292”附近），右图（X = 64”，Y = -299”附近）。光桥中的水平磁场约为 200 G，而周围区域高达 1,500 G。这些磁场足够强，足以产生 I-FIP 效应，这一效应得到了对等离子体参数的进一步分析的支持（例如— 密度和波幅）。总体而言，这些是形成光桥的磁通量管之间的区域中的间歇性加热和重联流出的特征，并且可以得出结论，光桥可能是磁重联的位置。