摘要
We present an analysis of rest-frame UV colors of 17,243 galaxies at$z\sim2-4$in the HST 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$M_\odot$ ) are typically bluer ( $\beta_{SED}=-2.0\pm 0.2$/$\beta_{PL} = -2.1\pm0.4$ ), fainter ( $MUV = -17.8^{+0.7}_{-0.6}$ ) less dusty ( $A{v}=0.4\pm0.1$mag), exhibit lower rates of star formation (log[SFR]= $0.1\pm0.2 M_\odot/$yr) and higher specific star formation rates (log[sSFR]= $-8.2\pm0.2 \ \mathrm{yr}^{-1}$ ) than their high-mass counterparts. Higher-mass galaxies (log[ $M_*$ ]$=10.0-12.0 \ M_\odot$ ) are on average redder ( $\beta_{SED}=-0.9^{+0.8}_{-0.5}$/$\beta_{PL}=-1.0^{+0.8}_{-0.5}$ ), brighter ( $MUV=-19.6^{+1.0}_{-1.2}$ ), dustier ( $Av = 0.9^{+0.5}_{-0.4}$mag), have higher SFRs (log[SFR]= $1.2^{+0.6}_{-1.1} M_\odot$yr), and lower sSFRs (log[sSFR]= $-9.1^{+0.5}_{-1.1} {yr}^{-1}$ ). 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$z\sim2-4$ , a relationship less discernible with smaller datasets typically available at higher redshifts.