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Register a new userUnraveling the Nature of Unidentified High Galactic Latitude Fermi/LAT Gamma-ray Sources with Suzaku
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We report on the results of deep X-ray follow-up observations of four unidentified Fermi/LAT gamma-ray sources at high Galactic latitudes using Suzaku. The studied objects were detected with high significance during the first 3 months of Fermi/LAT operation, and subsequently better localized in the Fermi/LAT 1 year catalog (1FGL). Possible associations with pulsars and active galaxies have subsequently been discussed, and our observations provide an important contribution to this debate. In particular, an X-ray point source was found within the 95% confidence error circle of 1FGL J1231.1-1410. X-ray spectrum is well-fitted by a blackbody with an additional power-law. This supports the recently claimed identification of this source with a millisecond pulsar (MSP) PSR J1231-1411. Concerning 1FGL J1311.7-3429, two X-ray sources were found within the LAT error circle. Even though the X-ray spectral and variability properties were accessed, their nature and relationship with the gamma-ray source remain uncertain. We found several weak X-ray sources in the field of 1FGL J1333.2+5056, one coinciding with CLASS J1333+5057. We argue the available data are consistent with the association between these two objects. Finally, we have detected an X-ray source in the vicinity of 1FGL J2017.3+0603. This object was recently suggested to be associated with a newly discovered MSP PSR J2017+0603, because of the spatial-coincidence and the gamma-ray pulse detection. We have only detected the X-ray counterpart of the CLASS J2017+0603, while we determined an X-ray flux upper limit at the pulsar position. All in all, our studies indicate while a significant fraction of unidentified high Galactic latitude gamma-ray sources is related to the pulsar and blazar phenomena, associations with other classes of astrophysical objects are still valid options.
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During a search for gamma-ray emission from NGC 3628 (Arp 317), two new unidentified gamma-ray sources, Fermi J1049.7+0435 and J1103.2+1145 have been discovered cite{ATel}. The detections are made in data from the Large Area Telescope (LAT), on board the Fermi Gamma-ray Space Telescope, in the 100,MeV to 300,GeV band during the period between 2008 August 5 and 2012 October 27. Neither is coincident with any source listed in the 2FGL catalogue cite{Nolan2012}. Fermi J1049.7+0435 is at Galactic coordinates $(l,b) = (245.34^circ, 53.27^circ)$, $(alpha_{J2000}, delta_{J2000}) = (162.43^circ, 4.60^circ)$. Fermi J1103.2+1145 is at Galactic coordinates $(l,b) = (238.85^circ, 60.33^circ)$, $(alpha_{J2000},delta_{J2000})= (165.81^circ, 11.75^circ)$. Possible radio counterparts are found for both sources, which show flat radio spectra similar to other Fermi LAT detected AGN, and their identifications are discussed. These identification have been supoorted by snap-shot observations with the Australia Telescope Compact Array at several epochs in 2013 and 2014,
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