The Fermi LAT Collaboration
We report the Fermi Large Area Telescope detection of gamma-ray (>100
megaelectronvolts) pulsations from pulsar J1823-3021A in the globular cluster
NGC 6624 with high significance (~7 sigma). Its gamma-ray luminosity L_gamma =
(8.4 +/- 1.6) x10^34 ergs per second, is the highest observed for any
millisecond pulsar (MSP) to date, and it accounts for most of the cluster
emission. The non-detection of the cluster in the off-pulse phase implies that
its contains < 32 gamma-ray MSPs, not ~100 as previously estimated. The
gamma-ray luminosity indicates that the unusually large rate of change of its
period is caused by its intrinsic spin-down. This implies that J1823-3021A, has
the largest magnetic field and is the youngest MSP ever detected, and that such
anomalous objects might be forming at rates comparable to those of the more
normal MSPs.
View original:
http://arxiv.org/abs/1111.3754
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