Thursday, March 14, 2013

Fermi LAT weekly report N. 248

Covered period: 2013.Mar.04-2013.Mar.10
LAT Mission week: 248.57 - 249.57

  • This week Fermi performed a Target of Opportunity pointing on the Crab Nebula. The source started with a daily flux of (6.6 +/-0.6) on March 4, then increased its average daily flux reaching a maximum flux value of (10.7+/-0.7) on March 6, 3.9 times the value reported in 2FGL. In the same day the maximum peak value of the week, (18.1+/-3.9), 6.6 times the 2FGL flux value, occurred during the last 6 hour run (18h-24h). At the end of the week the source decreased to the flux value of (6.0+/-0.6).
  • NGC 1275 began to appear the second day of the week (March 5) with low flux and significance, then on March 7 was been detected with its maximum daily flux value ever detected of (1.3+/-0.4), 7.3 times the 2FGL value, and it was seen also during the third six hour run (12h-18h) with very high flux (16 times 2FGL value).
  • On March 4 Mkn 421 was detected in a quite high state in both daily and the first 6 hour run (0h-6h) revealing flux values of respectively (0.9+/-0.2), 5 times 2FGL value, and (1.4+/-0.6), 7.5 times 2FGL value. The next 2 days the source disappeared and then was detected again until the end of the week, with progressively decreasing flux values from (1.1+/-0.2), on March 7, to (0.3+/-0.1) on March 10.
  • Blazar PKS 1424–418 was detected in high state the first day of the week, during the second (6h-12h) and the third(12h-18h) 6 hour runs with a daily flux of (1.9+/-0.3), that is 11 times greater than the mean value recorded in the 2FGL. The source appeared again the last 3 days of the week (March 8,9 and 10) with a daily flux value nearly halved.
  • PKS 1510-08 appeared on March 8 with increasing flux values: it was detected during the last 6 hour run with high significance, although undetected in the daily run. For the next 2 days it was detected with daily flux respectively of (1.2+/-0.2), 1.2 times 2FGL on March 9, and (1.5+/-0.3), 1.5 times 2FGL on March 10.During the last day it was detected also in the last 6 hour run (18h-24h) with a flux 2.8 times that of the 2FGL.
  • During this week 4 sources were seen in a flare status just for one day : the FSRQs S5 1044+71 and PKS 0502+049 seemed to reveal a quite high state during March 7, with daily flux value respectively of (0.3+/-0.1), 5.6 times the 2FGL value, and (0.4+/-0.2), 14 times the 2FGL value, although the last one was seen with low significance. PKS 1124–186 and PKS 2320–035 (March 9) revealed daily flux values 8.3 and 21 times the average fluxes reported in 2FGL.
  • GRB 130310A (GCN #14282) was detected by the LAT with the blind search on March 10 at low significance in the 6hr run.

Fluxes are in the unit of 10-6 photons/cm2/s above 100 MeV. All errors are statistical only.

Note. All the fluxes reported above are from the ASP analysis and should be considered preliminary and should not be used for publication, however they are indicative of the flux range and the current status of a source. Source association is done on the basis of source location, considering spatial coincidence only, and it is not indicative of an identification.
- Please acknowledge the LAT team if you use information from this report.

For questions and comments please contact:
- E. Antolini ( or D. Gasparrini ( for generic information related to this week
- Contact persons on this page for individual sources cited above.

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