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arXiv · 1012.4658

Radio and Gamma-Ray Constraints on the Emission Geometry and Birthplace of PSR J2043+2740

Abstract

We report on the first year of Fermi gamma-ray observations of pulsed high-energy emission from the old PSR J2043+2740. The study of the gamma-ray efficiency of such old pulsars gives us an insight into the evolution of pulsars' ability to emit in gammma rays as they age. The gamma-ray lightcurve of this pulsar above 0.1 GeV is clearly defined by two sharp peaks, 0.353+/-0.035 periods apart. We have combined the gamma-ray profile characteristics of PSR J2043+2740 with the geometrical properties of the pulsar's radio emission, derived from radio polarization data, and constrained the pulsar-beam geometry in the framework of a Two Pole Caustic and an Outer Gap model. The ranges of magnetic inclination and viewing angle were determined to be {alpha,zeta}~{52-57,61-68} for the Two Pole Caustic model, and {alpha,zeta}~{62-73,74-81} and {alpha,zeta}~{72-83,60-75} for the Outer Gap model. Based on this geometry, we assess possible birth locations for this pulsar and derive a likely proper motion, sufficiently high to be measurable with VLBI. At a characteristic age of 1.2 Myr, PSR J2043+2740 is the third oldest of all discovered, non-recycled, gamma-ray pulsars: it is twice as old as the next oldest, PSR J0357+32, and younger only than the recently discovered PSR J1836+5925 and PSR J2055+25, both of which are at least 5 and 10 times less energetic, respectively.

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A. Noutsos, A. A. Abdo, M. Ackermann, M. Ajello, J. Ballet, G. Barbiellini, M. G. Baring, D. Bastieri, K. Bechtol, R. Bellazzini, B. Berenji, E. Bonamente, A. W. Borgland, J. Bregeon, A. Brez, M. Brigida, P. Bruel, R. Buehler, G. Busetto, G. A. Caliandro, R. A. Cameron, F. Camilo, P. A. Caraveo, J. M. Casandjian, C. Cecchi, O. Celik, S. Chaty, A. Chekhtman, J. Chiang, S. Ciprini, R. Claus, I. Cognard, J. Cohen-Tanugi, S. Colafrancesco, S. Cutini, C. D. Dermer, F. de Palma, P. S. Drell, D. Dumora, C. M. Espinoza, C. Favuzzi, E. C. Ferrara, W. B. Focke, M. Frailis, P. C. C. Freire, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, S. Germani, N. Giglietto, F. Giordano, M. Giroletti, G. Godfrey, P. Grandi, I. A. Grenier, J. E. Grove, L. Guillemot, S. Guiriec, A. K. Harding, R. E. Hughes, M. S. Jackson, G. Johannesson, A. S. Johnson, T. J. Johnson, W. N. Johnson, S. Johnston, T. Kamae, H. Katagiri, J. Kataoka, J. Knoedlseder, M. Kramer, M. Kuss, J. Lande, S. -H. Lee, F. Longo, F. Loparco, M. N. Lovellette, P. Lubrano, A. G. Lyne, A. Makeev, M. Marelli, M. N. Mazziotta, J. E. McEnery, J. Mehault, P. F. Michelson, T. Mizuno, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, M. Naumann-Godo, P. L. Nolan, E. Nuss, T. Ohsugi, A. Okumura, N. Omodei, E. Orlando, J. F. Ormes. 2010-12-21. Radio and Gamma-Ray Constraints on the Emission Geometry and Birthplace of PSR J2043+2740. https://doi.org/10.1088/0004-637x/728/2/77

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