English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Off-the-limb observations with high spatial and spectral resolution will helpus understand the physical properties of spicules in the solar chromosphereSpectropolarimetric observations of spicules in the \ion{He}{i} 10830 \AA\multiplet were obtained with the Tenerife Infrared Polarimeter on the GermanVacuum Tower Telescope at the Observatorio del Teide (Tenerife, Spain). Theanalysis shows the variation of the off-limb emission profiles as a function ofthe distance to the visible solar limb. The ratio between the intensities ofthe blue and the red components of this triplet $({\cal R}=I_{\rm blue}/I_{\rmred})$ is an observational signature of the optical thickness along the lightpath, which is related to the intensity of the coronal irradiation. We presentobservations of the intensity profiles of spicules above a quiet Sun region.The observable ${\cal R}$ as a function of the distance to the visible limb isalso given. We have compared our observational results to the intensity ratioobtained from detailed radiative transfer calculations in semi-empirical modelsof the solar atmosphere assuming spherical geometry. The agreement is purelyqualitative. We argue that future models of the solar chromosphere andtransition region should account for the observational constraints presentedhere.

Spicule emission profiles observed in \ion{He}{i} 10830 \AA