Over the past two years , we used a series of GBT observations to uncover at least 33 millisecond pulsars in the globular cluster Terzan 5 located in the Galactic bulge .
We now have 32 timing solutions for the pulsars which give us precise positions and dispersion measures ( DMs ) and indicate that the DMs are dominated by variations in the integrated electron density along the slightly different sight lines towards the pulsars .
At a distance of \sim 8.7 kpc , angular separations between the pulsars range from 0.4 ^ { \prime \prime } - 100 ^ { \prime \prime } and correspond to projected physical separations of 0.01 - 4 pc , giving us a unique probe into the ionized ISM properties on these scales .
Our measurement of the DM structure function toward Terzan 5 is not inconsistent with Kolmogorov-like electron density fluctuations in the ISM on scales ranging from at least 0.2 - 2 pc .