On the Relationship between Radio and X-ray Signatures of Drifting Subpulses

Partially shielded vacuum gap model of the inner acceleration region in pulsars is examined with respect to the drifting subpulse phenomenon and the polar cap heating by E×B drifting sparks. The formula for the efficiency of X-ray luminosity from heated polar cap Lx/Ė ≈ (P̂3/P ) −2 was derived, which depends only on the observational tertiary subpulse drift periodicity P̂3. In PSR B0943+10 for which both Lx and P̂3 are known, this formula is perfectly satisfied. Based on several cases in which P̂3 is known it is argued that Lx/Ė ∼ 10 . This intriguing property was previously attributed to the pulsar magnetospheric emission. In this paper we suggest that this could also be a characteristic property of thermal emission from the heated polar cap.