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

The red giant L2 Pup started a dimming event in 1994, which is considered tobe caused by the ejection of dust clouds. We present near-IR aperture-synthesisimaging of L2 Pup achieved by combining data from VLT/NACO speckle observationsand long-baseline interferometric observations with the AMBER instrument of theVery Large Telescope Interferometer (VLTI). We also extracted an 8.7 micronimage from the mid-IR VLTI instrument MIDI. Our aim is to spatially resolve theinnermost region of the circumstellar environment. The diffraction-limitedimage at 2.27 micron obtained by bispectrum speckle interferometry with NACOwith a spatial resolution of 57 mas shows an elongated component. Theaperture-synthesis imaging combining the NACO speckle data and AMBER data(2.2--2.29 micron) with a spatial resolution of 5.6x7.3 mas further resolvesnot only this elongated component, but also the central star. The reconstructedimage reveals that the elongated component is a nearly edge-on disk with a sizeof ~180x50 mas lying in the E-W direction, and furthermore, that the southernhemisphere of the central star is severely obscured by the equatorial dust laneof the disk. The angular size of the disk is consistent with the distance thatthe dust clouds that were ejected at the onset of the dimming event should havetraveled by the time of our observations, if we assume that the dust cloudsmoved radially. This implies that the formation of the disk may be responsiblefor the dimming event. The 8.7 micron image with a spatial resolution of 220mas extracted from the MIDI data taken in 2004 (seven years before the AMBERand NACO observations) shows an approximately spherical envelope without asignature of the disk. This suggests that the mass loss before the dimmingevent may have been spherical.

AMBER-NACO aperture-synthesis imaging of the half-obscured central star and the edge-on disk of the red giant L2 Pup