Point Source Detection and Localization Update

1
Point Source Detection and Localization Update

• Using the UW HealPixel database on DC2_2 data
• Toby Burnett University of Washington

2
Procedure

• Create compact tuple with (ra, dec, energy,
  event_class) from 55 days.
• Create Healpixel array with 8 levels (6-13)
  depending on energy fill with classA Front only
  for now
• Generate density plots of full sky (AIT), or
  small regions (ZEA)
• Use current catalog list to apply simple maximum
  likelihood background/signal fits independently
  to each energy band
• If ?(TS)gt2, adjust position to maximize total
  likelihood
• Results are athttp//glast.phys.washington.edu/dc
  2/point/likelihood.htm, tab catalog-v1r2-DC2-2
  350 fits, 30 problems
• Sort according to position resolution, from
  0.0011 to 0.4 deg
• Also use for source finding

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DC2_2 photon density
Vela region
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Around Vela two very hard pulsars, another hard
unknown source
Vela0.0023?
(empty for test)
PSR_J0904m50080.0011?
MRF0141_v1r20.0031?
PSR_J0717m12350.0016?
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Analysis Details, questions

• See http//glast.phys.washington.edu/dc2/point/lik
  elihood.htm, tab Hard PSR
• Would EGRET have seen these sources?

EGRETAstron. Astrophys. 289, 855-867 (1994)
Sensitivity?
Note EGRET total is 6852 events mostly from 3
weeks of pointed observations during first year
scan. The DC2 55-day scan yields 7871 (front
only).
From the same EGRET paper Strong sources can be
located to an accuracy of about 0.1?.