Statistical Study of Rapid Blue Excursions as Mass Conduits in Solar Atmosphere

TL;DR

This study analyzes the dynamic properties of Rapid Blue Excursions (RBEs), transient chromospheric features, demonstrating their role as mass transfer conduits in the solar atmosphere through high-cadence spectral observations and automated tracking.

Contribution

It provides a comprehensive statistical analysis of RBE properties, including lifetimes, velocities, and lengths, highlighting their impulsive nature and significance in chromosphere-corona mass exchange.

Findings

RBEs have lifetimes mainly between 20-60 seconds.

Line-of-sight velocities range from 20 to 140 km/s.

RBEs contribute significantly to upward mass flux.

Abstract

Rapid Blue Excursions (RBEs) are transient blue-shifted chromospheric absorption features widely interpreted as the on-disk counterparts of Type II solar spicules. We investigate their dynamic properties using high-cadence spectral observations combined with automated detection and spatio-temporal tracking algorithms. RBEs were identified through blue-wing Doppler asymmetry criteria and tracked using spatial connectivity and centroid continuity methods to determine lifetimes and kinematic evolution. The statistical analysis shows that RBEs are short-lived events with lifetimes predominantly between 20 to 60 s and a mean duration of approximately 75 s. The lifetime distribution follows an exponential decay profile, indicative of impulsive driving. Line-of-sight velocities range from 20 to 140 km s-1, with a mean near 26 km s-1. Projected lengths span 1.2-5.5 Mm with sub-arcsecond widths, and recurrence analysis reveals repeated activity at localized magnetic footpoints. Mass flux estimates suggest that RBEs transport significant plasma upward, contributing to chromospheric mass supply toward the corona. These findings reinforce the role of RBEs as dynamic conduits of mass transfer and key elements in chromosphere-corona coupling.