Synchronous X-ray and Radio Mode Switches: A Rapid Global Transformation of the Pulsar Magnetosphere

Pondering Pulsars Pulsars are rapidly rotating, magnetized neutron stars that are powered by the loss of rotational energy. Because their emission is beamed, their light appears to pulse on and off at regular intervals. Changes in radio emission behavior have been observed for a number of pulsars, manifesting themselves as switches between ordered and disordered variations in intensity and pulse shapes, but these changes have not been seen at other wavelengths. Based on simultaneous radio and x-ray observations of pulsar PSR B0943+10, Hermsen et al. (p. 436) show that changes in emission state identified in radio measurements show counterpart fluctuations in the strength and temporal behavior of x-rays. Some of these changes were unexpected in their character and physical properties, challenging pulsar emission theories. The detection of synchronized switches in the radio and x-ray pulse properties of a pulsar challenges pulsar emission theories. Pulsars emit from low-frequency radio waves up to high-energy gamma-rays, generated anywhere from the stellar surface out to the edge of the magnetosphere. Detecting correlated mode changes across the electromagnetic spectrum is therefore key to understanding the physical relationship among the emission sites. Through simultaneous observations, we detected synchronous switching in the radio and x-ray emission properties of PSR B0943+10. When the pulsar is in a sustained radio-"bright" mode, the x-rays show only an unpulsed, nonthermal component. Conversely, when the pulsar is in a radio-"quiet" mode, the x-ray luminosity more than doubles and a 100% pulsed thermal component is observed along with the nonthermal component. This indicates rapid, global changes to the conditions in the magnetosphere, which challenge all proposed pulsar emission theories.

A. Noutsos | J. Eislöffel | M. J. Bentum | I. M. Avruch | M. Pilia | A. Shulevski | H. Falcke | S. Markoff | S. Yatawatta | A. Horneffer | V. N. Pandey | P. Weltevrede | P. Maat | A. Alexov | M. Kuniyoshi | P. Zarka | A. W. Gunst | W. Reich | A. Asgekar | W. Frieswijk | A. Bonafede | M. Iacobelli | M. Pandey-Pommier | C. Tasse | F. Breitling | B. Ciardi | S. Duscha | A. Karastergiou | V. I. Kondratiev | M. Mevius | H. Munk | H. Paas | A. G. Polatidis | J. Sluman | O. Wucknitz | J. de Plaa | F. Batejat | B. W. Stappers | K. Zagkouris | J. C. A. Miller-Jones | M. A. Garrett | S. Rawlings | M. W. Wise | R. Pizzo | M. Serylak | R. A. M. J. Wijers | A. Schoenmakers | H. Falcke | J. P. McKean | S. Rawlings | O. Wucknitz | F. Breitling | J. Hessels | B. Stappers | P. Zarka | J. van Leeuwen | P. Weltevrede | J. Miller-Jones | B. Ciardi | M. Steinmetz | H. Butcher | M. Bell | A. Horneffer | R. Pizzo | L. Bîrzan | A. Bonafede | G. Macario | H. Röttgering | C. Tasse | S. Yatawatta | V. Pandey | W. Frieswijk | M. Tagger | E. Keane | S. Markoff | A. Noutsos | L. Kuiper | A. Karastergiou | M. Wise | M. Brüggen | M. Garrett | R. Wijers | M. Kramer | W. Reich | J. Broderick | R. Fender | M. Bell | J. Grießmeier | V. Kondratiev | M. Serylak | C. Sobey | D. Mitra | M. Iacobelli | S. ter Veen | T. Hassall | M. Pilia | M. Pandey-Pommier | M. Hoeft | A. Alexov | A. Asgekar | M. Bentum | A. Gunst | M. Kuniyoshi | G. Kuper | P. Maat | H. Paas | A. Polatidis | A. Schoenmakers | J. Sluman | Y. Tang | F. Batejat | A. Shulevski | M. Mevius | I. Avruch | S. Duscha | H. Munk | F. de Gasperin | R. V. van Weeren | J. Eislöffel | L. Kuiper | F. de Gasperin | M. Brüggen | H. Röttgering | C. Sobey | J. W. T. Hessels | E. de Geus | M. Tagger | R. Fender | T. E. Hassall | M. Hoeft | Y. Tang | G. Wright | J. de Plaa | T. Coenen | J. Broderick | H. R. Butcher | G. Macario | G. Kuper | A. M. M. Scaife | R. J. van Weeren | E. Orrú | W. Hermsen | J. van Leeuwen | D. Mitra | J. M. Rankin | G. A. E. Wright | R. Basu | T. Coenen | J.-M. Grießmeier | E. Keane | M. Kramer | M. E. Bell | M. R. Bell | G. Bernardi | P. Best | L. Bîrzan | C. Ferrari | E. de Geus | G. Heald | R. Morganti | M. Steinmetz | S. ter Veen | R. Vermeulen | R. H. van de Brink | K. Zagkouris | P. Best | E. Orrú | C. Ferrari | W. Hermsen | R. Basu | G. Bernardi | G. Heald | R. Morganti | A. Scaife | R. Vermeulen

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