We report the discovery of gamma-ray pulsations from the nearby isolated millisecond pulsar (MSP) PSR J0030+0451 with the Large Area Telescope on the Fermi Gamma-ray Space Telescope (formerly GLAST). This discovery makes PSR J0030+0451 the second MSP to be detected in gamma rays after PSR J0218+4232, observed by the EGRET instrument on the Compton Gamma-Ray Observatory. The spin-down power (E) over dot = 3.5 x 10(33) erg s(-1) is an order of magnitude lower than the empirical lower bound of previously known gamma-ray pulsars. The emission profile is characterized by two narrow peaks, 0.07 +/- 0.01 and 0.08 +/- 0.02 wide, respectively, separated by 0.44 +/- 0.02 in phase. The first gamma-ray peak falls 0.15 +/- 0.01 after the main radio peak. The pulse shape is similar to that of the "normal" gamma-ray pulsars. An exponentially cutoff power-law fit of the emission spectrum leads to an integral photon flux above 100 MeV of (6.76 +/- 1.05 +/- 1.35) x 10(-8) cm(-2) s(-1) with cutoff energy (1.7 +/- 0.4 +/- 0.5) GeV. Based on its parallax distance of (300 +/- 90) pc, we obtain a gamma-ray efficiency L(gamma)/E similar or equal to 15% for the conversion of spin-down energy rate into gamma-ray radiation, assuming isotropic emission.
|Autori interni:||FAVUZZI, Cecilia|
|Titolo:||Pulsed gamma rays from the millisecond pulsar J0030+0451 with the fermi large area telescope|
|Rivista:||THE ASTROPHYSICAL JOURNAL|
|Data di pubblicazione:||2009|
|Digital Object Identifier (DOI):||10.1088/0004-637X/699/2/1171|
|Appare nelle tipologie:||1.1 Articolo in rivista|