We analyze the spectral energy distributions ( SEDs ) of Lyman break galaxies ( LBGs ) at z \simeq 1 – 3 selected using the Hubble Space Telescope ( HST ) Wide Field Camera 3 ( WFC3 ) UVIS channel filters .
These HST /WFC3 observations cover about 50 arcmin ^ { 2 } in the GOODS-South field as a part of the WFC3 Early Release Science program .
These LBGs at z \simeq 1 – 3 are selected using dropout selection criteria similar to high redshift LBGs .
The deep multi-band photometry in this field is used to identify best-fit SED models , from which we infer the following results : ( 1 ) the photometric redshift estimate of these dropout selected LBGs is accurate to within few percent ; ( 2 ) the UV spectral slope \beta is redder than at high redshift ( z > 3 ) , where LBGs are less dusty ; ( 3 ) on average , LBGs at z \simeq 1 – 3 are massive , dustier and more highly star-forming , compared to LBGs at higher redshifts with similar luminosities ( 0.1 L ^ { * } \lesssim L \lesssim 2.5 L ^ { * } ) , though their median values are similar within 1 \sigma uncertainties .
This could imply that identical dropout selection technique , at all redshifts , find physically similar galaxies ; and ( 4 ) the stellar masses of these LBGs are directly proportional to their UV luminosities with a logarithmic slope of \sim 0.46 , and star-formation rates are proportional to their stellar masses with a logarithmic slope of \sim 0.90 .
These relations hold true — within luminosities probed in this study — for LBGs from z \simeq 1.5 to 5 .
The star-forming galaxies selected using other color-based techniques show similar correlations at z \simeq 2 , but to avoid any selection biases , and for direct comparison with LBGs at z > 3 , a true Lyman break selection at z \simeq 2 is essential .
The future HST UV surveys , both wider and deeper , covering a large luminosity range are important to better understand LBG properties , and their evolution .