We have detected 12 new pulsars, including four of the short-period "recycled" variety, in a survey using the Arecibo radio telescope at 430 MHz. The survey covered 680 square degrees at right ascensions 21~h through 02~h, declinations +7° through +30°. Most of the region falls between Galactic latitudes — 20° and —50°. The minimum detectable flux density for long-period pulsars was approximately 0.5 mJy for declinations +14° < δ < +23°, rising to 0.7 mJy at the declination extremes. For periods P < 100 ms the minimum detectable flux density increased with decreasing period, especially for large dispersion measures; at P = 1.5 ms and DM = 10 cm~(-3) pc the detection threshold was about 10 mJy. Only one previously known pulsar lay within the search region, and it was detected easily. The newly discovered short-period pulsars include two isolated objects: PSR J2322 + 2057 (P = 4.81 ms, DM = 13 cm~(-3) pc), and PSR J2235 + 1506 (P = 59.8 ms, DM = 18 cm~(-3) pc); and two pulsars in nearly circular binary orbits: PSR J2229 + 2643 (P = 2.98 ms, DM = 23 cm~(-3) pc, orbital period P_b = 93d), and PSR J2317+ 1439 (P = 3.45 ms, DM = 22 cm~(-3) pc, P_b = 2.5~d). We present timing observations of three of these pulsars over 1.5-2.5 yr. Refined and extended data sets for PSRs J2235 + 1506 and J2317 + 1439 have allowed the first measurements of their proper motions, which imply velocities of (100 ± 40) km s~(-1) and (70 ± 30) km s~(-1) respectively. Timing measurements of PSR J2229 + 2643 show that it has the smallest period derivative of any known pulsar, P = (1.9 ± 0.2) x 10~(-21). We use this result to establish a new upper limit for the possible rate of change of the Newtonian constant of gravity, |G/G| < 3 x 10~(-11) yr~(-1).
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