Model-Independent Inference of Galaxy Star Formation Histories in the Local Volume
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F25%3A10509923" target="_blank" >RIV/00216208:11320/25:10509923 - isvavai.cz</a>
Result on the web
<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=JadDvoTmUG" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=JadDvoTmUG</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.3390/universe11100352" target="_blank" >10.3390/universe11100352</a>
Alternative languages
Result language
angličtina
Original language name
Model-Independent Inference of Galaxy Star Formation Histories in the Local Volume
Original language description
Understanding the diversity of star formation histories (SFHs) of galaxies is key to reconstructing their evolutionary paths. Traditional models often assume parametric forms such as delayed-tau or exponentially declining models, which may not reflect the actual variety of formation processes. We aim to assess what types of SFHs are consistent with the observed present-day star formation rates (SFR0) and time-averaged star formation rates (< SFR >) of galaxies in the Local Volume, without assuming any fixed functional form. We construct a non-parametric framework by generating large ensembles of randomized SFHs for each galaxy in the sample. For each SFH, we compute its predicted stellar mass and present-day SFR and retain only those consistent with the observed values within a 20% tolerance. We then infer the statistical distribution of power-law slopes eta (fitted as SFR(t)proportional to(t-t(start))(eta)) and 50% stellar mass formation times t50. Across the full sample of 555 galaxies, we find that approximate to 70% have flat SFHs (|eta|<= 0.01), approximate to 24% are mildly declining (eta<-0.01), and approximate to 6% are rising (eta>0.01). In the low-mass bin (M star<3x10(9)M(circle dot)), rising SFHs slightly increase (approximate to 7%) but remain a minority as the majority have flat SFHs. Both eta and t50 correlate strongly with the SFR ratio (Spearman rho>0.75, p << 10(-16)), indicating that the shape and timing of star formation are primarily governed by this ratio. The t(50) distribution shows sharp spikes near 7.74 and 7.86 Gyr, which we attribute to grid discretization combined with filtering, rather than a physical bimodality. Our results confirm that strongly declining SFH templates are disfavored in the Local Volume: most systems are consistent with flat long-term SFHs, with only mild decline or occasional rising. Importantly, this is demonstrated through a fully model-independent, data-driven approach, with per-galaxy uncertainties quantified using the standard error of eta and t50 from the ensemble of accepted SFHs.
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
I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace
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
Universe
ISSN
2218-1997
e-ISSN
2218-1997
Volume of the periodical
11
Issue of the periodical within the volume
10
Country of publishing house
CH - SWITZERLAND
Number of pages
18
Pages from-to
352
UT code for WoS article
001604497700001
EID of the result in the Scopus database
2-s2.0-105020076504