摘要
We present an analysis of rest-frame ultraviolet (UV) colors of 17,243 galaxies at z similar to 2-4 in the Hubble Space Telescope UVCANDELS fields: GOODS-N, GOODS-S, COSMOS, and EGS. Here, we study the rest-frame UV spectral slope, beta, measured via model spectra obtained via spectral energy distribution (SED) fitting, beta SED, and explore its correlation with various galaxy parameters-photometric redshift, UV magnitude, stellar mass, dust attenuation, star formation rate (SFR), and specific SFR-obtained via SED fitting with Dense Basis. We also obtain measurements for beta via photometric power-law fitting and compare them to our SED-fit-based results, finding good agreement on average. While we find little evolution in beta with redshift from z = 2-4 for the full population, there are clear correlations between beta (and related parameters) when binned by stellar mass. For this sample, lower-stellar-mass galaxies (log[M*] = 7.5-8.5 M circle dot) are typically bluer ( beta SED=-2.0-0.2+0.2 / beta PL=-2.1-0.4+0.4 ), fainter ( MUV=-17.8-0.6+0.7 ), and less dusty ( Av=0.4-0.1+0.1 mag), and they exhibit lower rates of star formation (log[SFR]= 0.1-0.2+0.2M circle dot yr-1 ) and higher specific star formation rates (log[sSFR] = -8.2-0.2+0.2yr-1 ) than their high-mass counterparts. Higher-mass galaxies (log[M*] = 10.0-12.0 M circle dot) are on average redder ( beta SED=-0.9-0.5+0.8 / beta PL=-1.0-0.5+0.8 ), brighter ( MUV=-19.6-1.2+1.0 ), and dustier ( Av=0.9-0.4+0.5 mag), and they have higher SFRs (log[SFR] = 1.2-1.1+0.6M circle dot yr-1 ) and lower sSFRs (log[sSFR] = -9.1-1.1+0.5yr-1 ). This study's substantial sample size provides a benchmark for demonstrating that the rest-frame UV spectral slope correlates with stellar-mass-dependent galaxy characteristics at z similar to 2-4, a relationship less discernible with the smaller data sets typically available at higher redshifts.