Abstract
We present timing solutions for 12 pulsars discovered in the Green Bank North
Celestial Cap (GBNCC) 350 MHz pulsar survey, including six millisecond pulsars
(MSPs), a double neutron star (DNS) system, and a pulsar orbiting a massive
white dwarf companion. Timing solutions presented here include 350 and 820 MHz
Green Bank Telescope data from initial confirmation and follow-up as well as a
dedicated timing campaign spanning one year. PSR J1122$-$3546 is an isolated
MSP, PSRs J1221$-$0633 and J1317$-$0157 are MSPs in black widow systems and
regularly exhibit eclipses, and PSRs J2022+2534 and J2039$-$3616 are MSPs that
can be timed with high precision and have been included in pulsar timing array
experiments seeking to detect low-frequency gravitational waves. PSRs
J1221$-$0633 and J2039$-$3616 have Fermi Large Area Telescope $\gamma$-ray
counterparts and also exhibit significant $\gamma$-ray pulsations. We measure
proper motion for three of the MSPs in this sample and estimate their space
velocities, which are typical compared to those of other MSPs. We have detected
the advance of periastron for PSR J1018$-$1523 and therefore measure the total
mass of the double neutron star system, $m_{\rm tot}=2.3\pm0.3$ M$_{\odot}$.
Long-term pulsar timing with data spanning more than one year is critical for
classifying recycled pulsars, carrying out detailed astrometry studies, and
shedding light on the wealth of information in these systems post-discovery.