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We report the discovery of two binary millisecond pulsars in thecore-collapsed globular cluster M30 using the Green Bank Telescope (GBT) at 20cm. PSR J2140-2310A (M30A) is an eclipsing 11-ms pulsar in a 4-hr circularorbit and PSR J2140-23B (M30B) is a 13-ms pulsar in an as yet undetermined butmost likely highly eccentric (e>0.5) and relativistic orbit. Timingobservations of M30A with a 20-month baseline have provided precisedeterminations of the pulsar's position (within 4" of the optical centroid ofthe cluster), and spin and orbital parameters, which constrain the mass of thecompanion star to be m_2 >~ 0.1Msun. The position of M30A is coincident with apossible thermal X-ray point source found in archival Chandra data which ismost likely due to emission from hot polar caps on the neutron star. Inaddition, there is a faint (V_555 ~ 23.8) star visible in archival HST F555Wdata that may be the companion to the pulsar. Eclipses of the pulsed radioemission from M30A by the ionized wind from the compact companion star show afrequency dependent duration (\propto\nu^{-\alpha} with \alpha ~ 0.4-0.5) anddelay the pulse arrival times near eclipse ingress and egress by up to 2-3 ms.Future observations of M30 may allow both the measurement of post-Keplerianorbital parameters from M30B and the detection of new pulsars due to theeffects of strong diffractive scintillation.Comment: 10 pages, 6 figures, Submitted to ApJ. This version includes many  recommended modifications, an improved structure, a new author, and a  completely redone optical analysi

Green Bank Telescope Discovery of Two Binary Millisecond Pulsars in the Globular Cluster M30