Details

Autor(en) / Beteiligte

• Spitler, L G
• Lee, K J
• Eatough, R P
• Kramer, M
• KARUPPUSAMY, R
• Bassa, C G
• Cognard, I
• Desvignes, G
• Lyne, A G
• Stappers, B W
• Bower, G C
• Cordes, J M
• Champion, D J
• Falcke, H

Titel

PULSE BROADENING MEASUREMENTS FROM THE GALACTIC CENTER PULSAR J1745-2900

Ist Teil von

• Astrophysical journal. Letters, 2014-01, Vol.780 (1), p.1-6

Ort / Verlag

United States: Bristol : IOP Publishing

Erscheinungsjahr

2014

Quelle

Free E-Journal (出版社公開部分のみ）

Beschreibungen/Notizen

• We present temporal scattering measurements of single pulses and average profiles of PSR J1745-2900, a magnetar recently discovered only 3 arcsec away from Sagittarius A* (Sgr A*), from 1.2 to 18.95 GHz using the Effelsberg 100 m Radio Telescope, the Nancay Decimetric Radio Telescope, and the Jodrell Bank Lovell Telescope. Single pulse analysis shows that the integrated pulse profile above 2 GHz is dominated by pulse jitter, while below 2 GHz the pulse profile shape is dominated by scattering. This is the first object in the Galactic center (GC) with both pulse broadening and angular broadening measurements. We measure a pulse broadening time scale at 1 GHz of [tau] sub(1GHz) = 1.3 + or - 0.2 and pulse broadening spectral index of alpha = -3.8 + or - 0.2, which is several orders of magnitude lower than predicted by the NE2001 model (Cordes & Lazio 2002). If this scattering time scale is representative of the GC as a whole, then previous surveys should have detected many pulsars. The lack of detections implies either our understanding of scattering in the GC is incomplete or there are fewer pulsars in the GC than previously predicted. Given that magnetars are a rare class of radio pulsar, there are likely many canonical and millisecond pulsars in the GC, and not surprisingly, scattering in the GC is spatially complex.