LOFAR discovery of a quiet emission mode in PSR B0823+26
Abstract
PSR B0823+26, a 0.53-s radio pulsar, displays a host of emission phenomena over timescales of seconds to (at least) hours, including nulling, subpulse drifting, and mode-changing. Studying pulsars like PSR B0823+26 provides further insight into the relationship between these various emission phenomena and what they might teach us about pulsar magnetospheres. Here we report on the LOFAR discovery that PSR B0823+26 has a weak and sporadically emitting 'quiet' (Q) emission mode that is over 100 times weaker (on average) and has a nulling fraction forty-times greater than that of the more regularly-emitting 'bright' (B) mode. Previously, the pulsar has been undetected in the Q-mode, and was assumed to be nulling continuously. PSR B0823+26 shows a further decrease in average flux just before the transition into the B-mode, and perhaps truly turns off completely at these times. Furthermore, simultaneous observations taken with the LOFAR, Westerbork, Lovell, and Effelsberg telescopes between 110 MHz and 2.7 GHz demonstrate that the transition between the Q-mode and B-mode occurs within one single rotation of the neutron star, and that it is concurrent across the range of frequencies observed.
Keywords
Cite
@article{arxiv.1505.03064,
title = {LOFAR discovery of a quiet emission mode in PSR B0823+26},
author = {C. Sobey and N. J. Young and J. W. T. Hessels and P. Weltevrede and A. Noutsos and B. W. Stappers and M. Kramer and C. Bassa and A. G. Lyne and V. I. Kondratiev and T. E. Hassall and E. F. Keane and A. V. Bilous and R. P. Breton and J. -M. Grießmeier and A. Karastergiou and M. Pilia and M. Serylak and S. ter Veen and J. van Leeuwen and A. Alexov and J. Anderson and A. Asgekar and I. M. Avruch and M. E. Bell and M. J. Bentum and G. Bernardi and P. Best and L. Bîrzan and A. Bonafede and F. Breitling and J. Broderick and M. Brüggen and A. Corstanje and D. Carbone and E. de Geus and M. de Vos and A. van Duin and S. Duscha and J. Eislöffel and H. Falcke and R. A. Fallows and R. Fender and C. Ferrari and W. Frieswijk and M. A. Garrett and A. W. Gunst and J. P. Hamaker and G. Heald and M. Hoeft and J. Hörandel and E. Jütte and G. Kuper and P. Maat and G. Mann and S. Markoff and R. McFadden and D. McKay-Bukowski and J. P. McKean and D. D. Mulcahy and H. Munk and A. Nelles and M. J. Norden and E. Orrù and H. Paas and M. Pandey-Pommier and V. N. Pandey and G. Pietka and R. Pizzo and A. G. Polatidis and D. Rafferty and A. Renting and H. Röttgering and A. Rowlinson and A. M. M. Scaife and D. Schwarz and J. Sluman and O. Smirnov and M. Steinmetz and A. Stewart and J. Swinbank and M. Tagger and Y. Tang and C. Tasse and S. Thoudam and C. Toribio and R. Vermeulen and C. Vocks and R. J. van Weeren and R. A. M. J. Wijers and M. W. Wise and O. Wucknitz and S. Yatawatta and P. Zarka},
journal= {arXiv preprint arXiv:1505.03064},
year = {2015}
}
Comments
15 pages, 8 figures, 2 tables, accepted for publication in MNRAS