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We present the Swift optical to X-ray spectral energy distributions (SEDs) of44 quasars at redshifts z~2 observed by Swift, part of a larger program toestablish and characterize the optical through X-ray SEDs of moderate-redshiftquasars. Here we outline our analysis approach and present preliminary analysisand results for the first third of the full quasar sample. Not all quasars inthe sample are detected in X-rays; all of the X-ray detected objects so far areradio loud. As expected for radio loud objects, they are X-ray bright relativeto radio-quiet quasars of comparable optical luminosities, with an averagealpha_ox = 1.39 +/- 0.03 (where alpha_ox is the power-law slope connecting themonochromatic flux at 2500 Ang and at 2 keV), and display hard X-ray spectra.We find integrated 3000 Ang - 25 keV accretion luminosities of between0.7*10^(46) erg s^(-1) and 5.2*10^(47) erg s^(-1). Based on single-epochspectroscopic virial black hole mass estimates, we find that these quasars areaccreting at substantial Eddington fractions, 0.1 \le L/LEdd \le 1.

A catalog of optical to X-ray spectral energy distributions of z~2 quasars observed with Swift. I: First results