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

We succeeded in observing two large spicules simultaneously with the AtacamaLarge Millimeter/submillimeter Array (ALMA), the Interface Region ImagingSpectrograph (IRIS), and the Atmospheric Imaging Assembly (AIA) onboard theSolar Dynamics Observatory. One is a spicule seen in the IRIS Mg II slit-jawimages and AIA 304\AA\ images (MgII/304A spicule). The other one is a spiculeseen in the 100GHz images obtained with ALMA (100GHz spicule). Although the100GHz spicule overlapped with the MgII/304A spicule in the early phase, it didnot show any corresponding structures in the IRIS Mg II and AIA 304A imagesafter the early phase. It suggests that the spicules are individual events anddo not have a physical relationship. To obtain the physical parameters of the100GHz spicule, we estimate the optical depths as a function of temperature anddensity using two different methods. One is using the observed brightnesstemperature by assuming a filling factor, and the other is using an emissionmodel for the optical depth. As a result of comparing them, the kinetictemperature of the plasma and the number density of ionized hydrogens in the100GHz spicule are ~6800 K and 2.2 x 10^10 cm^-3. The estimated values canexplain the absorbing structure in the 193A image, which appear as acounterpart of the 100GHz spicule. These results suggest that the 100GHzspicule presented in this paper is classified to a macrospicule without a hotsheath in former terminology.

Estimating the temperature and density of a spicule from 100 GHz data obtained with ALMA