Statistical Analysis of Small Ellerman Bomb Events

TL;DR

This study uses high-resolution solar observations to analyze Ellerman bombs, revealing they are smaller and shorter-lived than previously thought, and suggesting magnetic reconnection as a possible driving mechanism.

Contribution

Developed a new tracking algorithm for EBs, providing more accurate size and lifetime estimates, and linked their occurrence to magnetic field configurations.

Findings

EBs are often around 0.3" in size and last less than 1 minute.

A correlation exists between G-band bright points and EBs.

EB energetics follow a power-law distribution consistent with nano-flare energies.

Abstract

The properties of Ellerman bombs (EBs), small-scale brightenings in the H-alpha line wings, have proved difficult to establish due to their size being close to the spatial resolution of even the most advanced telescopes. Here, we aim to infer the size and lifetime of EBs using high-resolution data of an emerging active region collected using the Interferometric BIdimensional Spectrometer (IBIS) and Rapid Oscillations of the Solar Atmosphere (ROSA) instruments as well as the Helioseismic and Magnetic Imager (HMI) onboard the Solar Dynamics Observatory (SDO). We develop an algorithm to track EBs through their evolution, finding that EBs can often be much smaller (around 0.3") and shorter lived (less than 1 minute) than previous estimates. A correlation between G-band magnetic bright points and EBs is also found. Combining SDO/HMI and G-band data gives a good proxy of the polarity for the vertical magnetic field. It is found that EBs often occur both over regions of opposite polarity flux and strong unipolar fields, possibly hinting at magnetic reconnection as a driver of these events.The energetics of EB events is found to follow a power-law distribution in the range of "nano-flare" (10^{22-25} ergs).