edu.ucar.opensky::articles:6848 UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact 2025-12-26T15:32:14.053697 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) https://n2t.org/ark:/85065/d7kd1z5r Spicule emission profiles observed in He I 10 830 Å 2007-09-04T00:00:00Z publication https://n2t.org/ark:/85065/d7kd1z5r https://doi.org/10.1051/0004-6361:20077936 Sanchez-Andrade Nuno, B. author Centeno, Rebecca author Puschmann, K. author Trujillo Bueno, J. author Blanco-Rodriguez, J. author Kneer, F. author UCAR/NCAR - Library publisher Off-the-limb observations with high spatial and spectral resolution will help us understand the physical properties of spicules in the solar chromosphere. Methods. Spectropolarimetric observations of spicules in the He I 10 830 Å multiplet were obtained with the Tenerife Infrared Polarimeter on the German Vacuum Tower Telescope at the Observatorio del Teide (Tenerife, Spain). The analysis shows the variation of the off-limb emission profiles as a function of the distance to the visible solar limb. The ratio between the intensities of the blue and the red components of this triplet (R = Iblue/Ired) is an observational signature of the optical thickness along the light path, which is related to the intensity of the coronal irradiation. Results. We present observations of the intensity profiles of spicules above a quiet Sun region. The observable R as a function of the distance to the visible limb is also given. We have compared our observational results to the intensity ratio obtained from detailed radiative transfer calculations in semi-empirical models of the solar atmosphere assuming spherical geometry. The agreement is purely qualitative. We argue that future models of the solar chromosphere and transition region should account for the observational constraints presented here. UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact PDF Text theme Resource Type 2016-01-01T00:00:00Z publication Copyright 2007 European Southern Observatory. None eng geoscientificInformation