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Since the large amplitude 2007 outburst which heated its accreting, pulsatingwhite dwarf, the dwarf nova system GW Librae has been cooling to its quiescenttemperature. Our Hubble Space Telescope ultraviolet spectra combined withground-based optical coverage during the 3rd and 4th year after outburst showthat the fluxes and temperatures are still higher than quiescence (T=19,700Kand 17,300K vs 16,000K pre-outburst for a log g=8.7 and d=100 pc). The K{wd} of7.6+/-0.8 km/s determined from the CI1463 absorption line, as well as thegravitational redshift implies a white dwarf mass of 0.79+/-0.08 Msun. Thewidths of the UV lines imply a white dwarf rotation velocity vsin i of 40 km/sand a spin period of 209 s (for an inclination of 11 deg and a white dwarfradius of 7x10^{8} cm). Light curves produced from the UV spectra in both yearsshow a prominent multiplet near 290 s, with higher amplitude in the UV comparedto the optical, and increased amplitude in 2011 vs 2010. As the presence ofthis set of periods is intermittent in the optical on weekly timescales, it isunclear how this relates to the non-radial pulsations evident duringquiescence.

HST and Optical Data Reveal White Dwarf Cooling, Spin and Periodicities in GW Librae 3-4 Years after Outburst