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

Nearby associations are ideal regions to study coeval samples ofprotoplanetary and debris disks down to late M-type stars. Those aged5-10,Myrs, where most of the disk should have already dissipated formingplanets, are of particular interest. We present the first complete study ofboth protoplanetary and debris disks in a young region, using the $\eta$Chamaeleontis association as a test bench to study the cold disk content. Weobtained sub-millimeter data for the entire core population down to late M-typestars, plus a few halo members. We performed a continuum sub-millimeter surveywith APEX/LABOCA of all the core populations of $\eta$ Cha association. Diskproperties have been derived by modeling protoplanetary and debris disks usingRADMC 2D and DMS, respectively. We find that protoplanetary disks in $\eta$ Chatypically have holes with radii of the order of 0.01 to 0.03 AU, whilering-like emission from the debris disks is located between 20 au and 650 aufrom the central star. The parallaxes and Gaia eDR3 photometry, in combinationwith the PARSEC and COLIBRI isochrones, enable us to confirm an age of $\eta$Cha between 7 and 9 Myrs. In general, the disk mass seems insufficient tosupport accretion over a long time, even for the lowest mass accretors, a cleardifference compared with other regions and also a sign that the mass budget isfurther underestimated. We do not find a correlation between the stellarmasses, accretion rates, and disk masses, although this could be due to sampleissues. We confirm that the presence of inner holes is not enough to stopaccretion unless accompanied by dramatic changes to the total disk masscontent. Comparing $\eta$ Cha with other regions at different ages, we findthat the physical processes responsible for debris disks (e.g., dust growth,dust trapping) efficiently act in less than 5 Myrs.

Protoplanetary and debris disks in the $\eta$ Chamaeleontis Association: A sub-millimeter survey obtained with APEX/LABOCA