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

[Abridged] Debris disks are extrasolar analogs to the solar systemplanetesimal belts. The star Fomalhaut harbors a cold debris belt at 140 AU aswell as evidence of a warm dust component, which is suspected of being a brightanalog to the solar system's zodiacal dust.  Interferometric observations obtained with the VLTI and the KIN haveidentified near- and mid-infrared excesses attributed to hot and warmexozodiacal dust in the inner few AU of the star.  We performed parametric modeling of the exozodiacal disk using the GRaTeRradiative transfer code to reproduce the interferometric data, complemented bymid- to far-infrared measurements. A detailed treatment of sublimationtemperatures was introduced to explore the hot population at the sublimationrim. We then used an analytical approach to successively testing several sourcemechanisms.  A good fit to the data is found by two distinct dust populations: (1) verysmall, hence unbound, hot dust grains confined in a narrow region at thesublimation rim of carbonaceous material; (2) bound grains at 2 AU that areprotected from sublimation and have a higher mass despite their fainter fluxlevel. We propose that the hot dust is produced by the release of small carbongrains following the disruption of aggregates that originate from the warmcomponent. A mechanism, such as gas braking, is required to further confine thesmall grains for a long enough time. In situ dust production could hardly beensured for the age of the star, so the observed amount of dust must betriggered by intense dynamical activity.  Fomalhaut may be representative of exozodis that are currently being surveyedworldwide. We propose a framework for reconciling the hot exozodi phenomenonwith theoretical constraints: the hot component of Fomalhaut is likely the tipof the iceberg since it could originate from a warm counterpart residing nearthe ice line.

An interferometric study of the Fomalhaut inner debris disk. III. Detailed models of the exozodiacal disk and its origin