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Periodic quasars have been suggested as candidates for hosting binarysupermassive black holes (SMBHs), although alternative scenarios remainpossible to explain the optical light curve periodicity. To test thealternative hypothesis of precessing radio jet, we present deep 6 GHz radioimaging conducted with NSF's Karl G. Jansky Very Large Array (VLA) in its Cconfiguration for the three candidate periodic quasars, DESJ024703.24$-$010032.0, DES J024944.66$-$000036.8, and DESJ025214.67$-$002813.7. Our targets were selected based on their opticalvariability using 20-yr long multi-color light curves from the Dark EnergySurvey (DES) and the Sloan Digital Sky Survey (SDSS). The new VLA observationsshow that all three periodic quasars are radio-quiet with the radio loudnessparameters measured to be $R\equiv f_{6\,{\rm cm}}/f_{{\rm 2500}}$ of$\lesssim$1.0$-$1.5 and the $k$-corrected luminosities $\nu L_\nu$[6 GHz] of$\lesssim$5$-$21 $\times$ 10$^{39}$ erg s$^{-1}$. They are in stark contrast topreviously known periodic quasars proposed as binary SMBH candidates such asthe blazar OJ 287 and PG1302$-$102. Our results rule out optical emissioncontributed from precessing radio jets as the origin of the optical periodicityin the three DES$-$SDSS-selected candidate periodic quasars. Future continuedoptical monitoring and complementary multi-wavelength observations are stillneeded to further test the binary SMBH hypothesis as well as other competingscenarios to explain the optical periodicity.

Very Large Array imaging rules out precessing radio jets in three DES$-$SDSS-selected candidate periodic quasars