While the Swift satellite is primarily designed to study gamma-ray bursts , its ultraviolet and optical imaging and spectroscopy capabilities are also being used for a variety of scientific programs .
In this study , we use the UV/Optical Telescope ( UVOT ) instrument aboard Swift to discover 0.5 < z < 2 Lyman break galaxies ( LBGs ) .
UVOT has covered \sim 266 arcmin ^ { 2 } at > 60ks exposure time , achieving a limiting magnitude of u < 24.5 , in the Chandra Deep Field South ( CDF-S ) .
Applying UVOT near-ultraviolet color selection , we select 50 UV-dropouts from this UVOT CDF-S data .
We match the selected sources with available multiwavelength data from GOODS-South , MUSYC , and COMBO-17 to characterize the spectral energy distributions for these galaxies and determine stellar masses , star formation rates ( SFRs ) , and dust attenuations .
We compare these properties for LBGs selected in this paper versus z \sim 3 LBGs and other CDF-S galaxies in the same redshift range ( 0.5 < z < 2 ) , identified using photometric redshift techniques .
The z \sim 1 LBGs have stellar masses of \langle Log~ { } M _ { * } / M _ { \odot } \rangle = 9.4 \pm 0.6 , which is slightly lower than z \sim 3 LBGs ( \langle Log~ { } M _ { * } / M _ { \odot } \rangle = 10.2 \pm 0.4 ) and slightly higher compared to the z \sim 1 CDF-S galaxies ( \langle Log~ { } M _ { * } / M _ { \odot } \rangle = 8.7 \pm 0.7 ) .
Similarly , our sample of z \sim 1 LBGs has SFRs ( derived using both ultraviolet and infrared data , where available ) of \langle Log~ { } SFR / ( M _ { \odot } ~ { } yr ^ { -1 } ) \rangle = 0.7 \pm 0.6 , which is nearly an order of magnitude lower than z \sim 3 LBGs ( \langle Log~ { } SFR / { M _ { \odot } ~ { } yr ^ { -1 } } \rangle = 1.5 \pm 0.4 ) , but slightly higher than the comparison z \sim 1 sample of CDF-S galaxies ( \langle Log~ { } SFR / { M _ { \odot } ~ { } yr ^ { -1 } } \rangle = 0.2 \pm 0.7 ) .
We find that our z \sim 1 UV-dropouts have \langle A _ { FUV } \rangle = 2.0 \pm 1.0 , which is higher than z \sim 3 LBGs ( \langle A _ { FUV } \rangle = 1.0 \pm 0.5 ) , but is similar to the distribution of dust attenuations in the other CDF-S galaxies ( \langle A _ { FUV } \rangle \sim 2.8 \pm 1.5 ) .
Using the GOODS-South multiwavelength catalog of galaxies , we simulate a larger and fainter sample of LBGs to compare their properties with those of the UVOT-selected LBG sample .
We conclude that UVOT can be useful for finding and studying the bright end of 0.5 < z < 2.0 LBGs .