Star formation properties in the Local Volume galaxies via $H\alpha$ and FUV fluxes

TL;DR

This study analyzes star formation rates in nearby galaxies using H-alpha and FUV data, revealing that most galaxies sustain their stellar mass over cosmic time and that starburst activity is rare among certain galaxy types.

Contribution

It provides a comprehensive catalog of star formation rates for 802 nearby galaxies and examines their scaling relations and star formation histories.

Findings

Most galaxies have enough gas to sustain current SFRs over the age of the universe.

Starburst activity is rare among BCD, Im, and Ir galaxies.

Internal processes mainly drive star formation in spiral and dwarf galaxies.

Abstract

A distance-limited sample of 869 objects from the Updated Nearby Galaxy Catalog is used to characterize the star formation status of the Local Volume population. We present a compiled list of 1217 star formation rate (SFR) estimates for 802 galaxies within 11 Mpc from us, derived from the H-alpha imaging surveys and GALEX far-ultraviolet survey. We briefly discuss some basic scaling relations between SFR and luminosity, morphology, HI-mass, surface brightness, as well as environment of the galaxies. About 3/4 of our sample consist of dwarf galaxies, for which we offer a more refined classification. We note that the specific star formation rate of nearly all luminous and dwarf galaxies does not exceed the maximum value: $\log(SFR/L_K) = -9.4$ [yr$^{-1}$]. The bulk of spiral and blue dwarf galaxies have enough time to generate their stellar mass during the cosmological time, $T_0$, with the observed SFRs. They dispose of a sufficient amount of gas to support their present SFRs over the next $T_0$ term. We note that only a minor part of BCD, Im, and Ir galaxies (about 1/20) proceeds in a mode of vigorous star-burst activity. In general, the star formation history of spiral and blue dwarf galaxies is mainly driven by their internal processes. The present SFRs of E, S0 and dSph galaxies are typically (1/30 - 1/300) of their former activity.