Optical and Near-Infrared Observations of SN 2013DX Associated with GRB 130702A

We present optical and near-infrared (NIR) light curves and optical spectra of SN 2013dx, associated with the nearby (redshift 0.145) gamma-ray burst GRB 130702A. The prompt isotropic gamma-ray energy released from GRB 130702A is measured to be E(sub gamma, iso) = 6.4(+1.3/-1.0) x 10(exp 50) erg (1 keV to 10 MeV in the rest frame), placing it intermediate between low-luminosity GRBs like GRB 980425/SN 1998bw and the broader cosmological population. We compare the observed g'r'i'z' light curves of SN 2013dx to a SN 1998bw template, finding that SN 2013dx evolves approx. 20% faster (steeper rise time), with a comparable peak luminosity. Spectroscopically, SN 2013dx resembles other broad-lined SNe Ic, both associated with (SN 2006aj and SN 1998bw) and lacking (SN 1997ef, SN 2007I, and SN 2010ah) gamma-ray emission, with photospheric velocities around peak of approx. 21,000 km/s. We construct a quasi-bolometric (g'r'z'yJ) light curve for SN 2013dx, only the fifth GRB-associated SN with extensive NIR coverage and the third with a bolometric light curve extending beyond (Delta)t > 40 days. Together with the measured photospheric velocity, we derive basic explosion parameters using simple analytic models. We infer a Ni-56 mass of M(sub Ni) = 0.37+/- 0.01 Stellar Mass, an ejecta mass of M(sub ej) = 3.1+/- 0.1 Stellar Mass, and a kinetic energy of E(sub K) = (8.2+/- 0.43) x 10(exp 51) erg (statistical uncertainties only), consistent with previous GRB-associated supernovae. When considering the ensemble population of GRB-associated supernovae, we find no correlation between the mass of synthesized Ni-56 and high-energy properties, despite clear predictions from numerical simulations that M(sub Ni) should correlate with the degree of asymmetry. On the other hand, M(sub Ni) clearly correlates with the kinetic energy of the supernova ejecta across a wide range of core-collapse events.