Radio-wave scattering is enhanced dramatically for galactic center sources in a region with radius \gtrsim 15 arc min .
Using scattering from Sgr A ^ { * } and other sources , we show that pulse broadening for pulsars in the Galactic center is at least 6.3 \nu ^ { -4 } seconds ( \nu = radio frequency in GHz ) and is most likely 50–200 times larger because the relevant scattering screen appears to be within the Galactic center region itself .
Pulsars beyond—but viewed through—the Galactic center suffer even greater pulse broadening and are angularly broadened by up to \sim 2 arc min .
Periodicity searches at radio frequencies are likely to find only long period pulsars and , then , only if optimized by using frequencies \gtrsim 7 GHz and by testing for small numbers of harmonics in the power spectrum .
The optimal frequency is \nu \sim 7.3 { GHz } ( \Delta _ { 0.1 } P \sqrt { \alpha } ) ^ { -1 / 4 } where \Delta _ { 0.1 } is the distance of the scattering region from Sgr A ^ { * } in units of 0.1 kpc , P is the period ( seconds ) , and \alpha is the spectral index .
A search for compact sources using aperture synthesis may be far more successful than searches for periodicities because the angular broadening is not so large as to desensitize the survey .
We estimate that the number of detectable pulsars in the Galactic center may range from \leq 1 to 100 , with the larger values resulting from recent , vigorous starbursts .
Such pulsars provide unique opportunities for probing the ionized gas , gravitational potential , and stellar population near Sgr A ^ { * } .