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 Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We study the absorption of scalar fields by extreme/exotic compact objects(ECOs) -- horizonless alternatives to black holes -- via a simple model inwhich dissipative mechanisms are encapsulated in a single parameter. Trappedmodes, localized between the ECO core and the potential barrier at thephotosphere, generate Breit-Wigner-type spectral lines in the absorption crosssection. Absorption is enhanced whenever the wave frequency resonates with atrapped mode, leading to a spectral profile which differs qualitatively fromthat of a black hole. We introduce a model based on Nariai spacetime, in whichproperties of the spectral lines are calculated in closed form. We presentnumerically calculated absorption cross sections and transmission factors forexample scenarios, and show how the Nariai model captures the essentialfeatures. We argue that, in principle, ECOs can be distinguished from blackholes through their absorption spectra.

Spectral lines of extreme compact objects