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تسجيل مستخدم جديدAn Updated Search of Steady TeV $gamma-$Ray Point Sources in Northern Hemisphere Using the Tibet Air Shower Array
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Using the data taken from Tibet II High Density (HD) Array (1997 February-1999 September) and Tibet-III array (1999 November-2005 November), our previous northern sky survey for TeV $gamma-$ray point sources has now been updated by a factor of 2.8 improved statistics. From $0.0^{circ}$ to $60.0^{circ}$ in declination (Dec) range, no new TeV $gamma-$ray point sources with sufficiently high significance were identified while the well-known Crab Nebula and Mrk421 remain to be the brightest TeV $gamma-$ray sources within the field of view of the Tibet air shower array. Based on the currently available data and at the 90% confidence level (C.L.), the flux upper limits for different power law index assumption are re-derived, which are approximately improved by 1.7 times as compared with our previous reported limits.
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