ALMA Reveals Diverse Dust-to-gas Mass Ratios and Quenching Modes in Old Quiescent Galaxies
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985815%3A90106%2F25%3A00646490" target="_blank" >RIV/67985815:90106/25:00646490 - isvavai.cz</a>
Result on the web
<a href="https://doi.org/10.3847/2041-8213/ae226c" target="_blank" >https://doi.org/10.3847/2041-8213/ae226c</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.3847/2041-8213/ae226c" target="_blank" >10.3847/2041-8213/ae226c</a>
Alternative languages
Result language
angličtina
Original language name
ALMA Reveals Diverse Dust-to-gas Mass Ratios and Quenching Modes in Old Quiescent Galaxies
Original language description
Recent discoveries of dust and molecular gas in quiescent galaxies (QGs) up to z similar to 4 challenge the long-standing view that the interstellar medium depletes rapidly once star formation ceases, raising key questions of whether dust and gas coevolve in QGs, and how their depletion links to stellar aging. We present deep Atacama Large Millimeter/submillimeter Array Band 6 continuum and CO(3-2) observations of 17 QGs at z similar to 0.4 in the COSMOS field. Using the dust-to-molecular gas mass ratio (delta DGR) as a key diagnostic, we trace postquenching evolution of the cold interstellar medium. Our study triples the number of QGs with direct delta DGR estimates, constraining 12 systems with stellar population ages of similar to 5-10 Gyr. For the first time, we show that delta DGR in QGs ranges from similar to 8x below to similar to 2.5x above the canonical value of delta DGR similar to 1/100. Despite uniformly low molecular gas fractions (median fH2=MH2/M star similar to 4.1% ), QGs follow diverse evolutionary paths: about half exhibit rapid (similar to 700 Myr) exponential dust decline with age, while the rest show mild decline over greater than or similar to 2 Gyr, maintaining elevated delta DGR greater than or similar to 1/100. Our results support simulations' predictions of dust and molecular gas evolving independently postquenching, without a preferred quenching mode. This challenges the use of dust continuum as a H2 tracer, implying that quenching cannot be robustly linked to interstellar medium conditions when relying solely on dust or gas.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
10308 - Astronomy (including astrophysics,space science)
Result continuities
Project
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Continuities
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Others
Publication year
2025
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Astrophysical Journal Letters
ISSN
2041-8205
e-ISSN
2041-8213
Volume of the periodical
995
Issue of the periodical within the volume
2
Country of publishing house
US - UNITED STATES
Number of pages
11
Pages from-to
L63
UT code for WoS article
001640149300001
EID of the result in the Scopus database
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