Exploring the correlation between Hα-to-UV ratio and burstiness for typical star-forming galaxies at z ∼ 2

The -to-UV luminosity ratio () is often used to probe bursty star formation histories (SFHs) of star-forming galaxies and it is important to validate it against other proxies for burstiness. To address this issue, we present a statistical analysis of the resolved distribution of star formation rate surface density (Sigma(SFR)) as well as stellar age and their correlations with the globally measured for a sample of 310 star-forming galaxies in two redshift bins of 1.37 < z < 1.70 and 2.09 < z < 2.61 observed by the MOSFIRE Deep Evolution Field (MOSDEF) survey. We use the multiwaveband CANDELS/3D-HST imaging of MOSDEF galaxies to construct Sigma(SFR) and stellar age maps. We analyse the composite rest-frame far-ultraviolet spectra of a subsample of MOSFIRE Deep Evolution Field (MOSDEF) targets obtained by the Keck Low Resolution Imager and Spectrometer (LRIS), which includes 124 star-forming galaxies (MOSDEF-LRIS) at redshifts 1.4 < z < 2.6, to examine the average stellar population properties, and the strength of age-sensitive far-ultraviolet spectral features in bins of . Our results show no significant evidence that individual galaxies with higher are undergoing a burst of star formation based on the resolved distribution of Sigma(SFR) of individual star-forming galaxies. We segregate the sample into subsets with low and high . The high- subset exhibits, on average, an age of = 8.0, compared to to log[Age/yr] = 8.4 for the low- galaxies, though the difference in age is significant at only the 2 sigma level. Furthermore, we find no variation in the strengths of Siiv lambda lambda 1393, 1402 and Civ lambda lambda 1548, 1550 P-Cygni features from massive stars between the two subsamples, suggesting that the high- galaxies are not preferentially undergoing a burst compared to galaxies with lower . On the other hand, we find that the high- galaxies exhibit, on average, more intense Heii lambda 1640 emission, which may possibly suggest the presence of a higher abundance of high-mass X-ray binaries.