The source of unusual coronal upflows with photospheric abundance in a solar active region

HARRA, L.; MANDRINI, C.H.; BROOKS, D. H.; BARCZYNSKI, K.; MAC CORMACK, C.; CRISTIANI, G.; MANDAL, S.; STERLING, A.C.; MARTINEZ PILLET, V.; JANITZEK, N.; SCHÜHLE, U.; BERGHMANS, D.; AUCHÈRE, F.; AZNAR CUADRADO, R.; BUCHLIN, E.; KRAAIKAMP, E.; LONG, D.

ASTRONOMY AND ASTROPHYSICS

EDP SCIENCES S A

Año: 2023

0004-6361

Context. Upflows in the corona are of importance as they may contribute to the solar wind. Because of this, there has been interestin the analysis of upflows at the edges of active regions (ARs). The coronal upflows that are seen at the edges of ARs have coronalelemental composition and can contribute to the slow solar wind. The sources of the upflows have been challenging to determinebecause they may be multiple and the spatial resolution of previous observations is not yet good enough.Aims. In this article, we analyse coronal upflows that are unusually close to the sunspot umbra in AR 12960. We analyse theirproperties and we attempt to determine if it is possible that they can feed into the slow solar wind.Methods. We analyse in detail the activity using a combination of Solar Orbiter EUV images at high spatial and temporal resolution,Hinode/EUV Imaging Spectrometer data, and observations from instruments on board the Solar Dynamics Observatory. This com-bined dataset was acquired during the first Solar Orbiter perihelion of the science phase, which provided a spatial resolution of 356km for 2 pixels. Doppler velocity, density, and plasma composition determinations, as well as coronal magnetic field modeling arecarried out to understand the source of the upflows.Results. Small magnetic fragments, called moving magnetic features (MMFs), are seen moving away from the sunspot in the AR.In particular, towards the west of the preceding sunspot at the edge of the penumbra, a small positive polarity connects to the umbravia small-scale and very dynamic coronal loops. At this location, small dark grains are evident flowing along penumbral filaments incontinuum images. The magnetic field modelling shows small low lying loops anchored close to the umbral magnetic field. The SolarOrbiter EUV Imagers (EUI) high-resolution data show the dynamics of these small loops, which last on timescales of only minutes.This is the location of the coronal upflow which has photospheric abundance.