Thursday, March 21, 2013

Fermi LAT Weekly report N. 249


Covered period: 2013 Mar. 11-17
LAT Mission week: 249.57 - 250.57

  • Gamma-ray flare from a source positionally consistent with the flat spectrum radio quasar S5 1217+71 (also known as TXS 1217+713 and 2FGL J1219.2+7107,z=0.451). The source is detected on March 11 with daily flux (0.6 +/- 0.2)E-6 and on March 12 with daily flux (0.5 +/- 0.1)E-6, about 90 times greater than the average flux reported in the 2FGL catalog (see ATel#4885).
  • PKS 1424-41 in enduring flaring state (daily flux between 1.1E-6 and 1.6E-6).
  • PKS 1510-08 in high state (about 1.9E-6) from March 11 to March 13 then fading in the following days of the week.
  • NGC 1275 in high state (detected with daily flux 0.7E-6 all the days from March 15 to 17).
  • Mkn 421 rather active (detected all the days with a daily flux between 0.4E-4 and 0.6E-6).
  • Rapid flare of CTA 102 on March 15 (1.3E-6). 
  • 3C 454.3 detected at a daily flux level of 0.8E-6 on March 13 and 14.
  • Crab nebula source dimmed at a level of about 4E-6 in the second half of the week.
  • Other blazars detected, also in a single day, during the week, with daily flux value equal or below 0.6E-6 are: PKS 1124-186, PKS 0537-441, PKS 0426-380, PKS 0454-234, 4C +38.41 (also known as B2 1633+38, OS 356), and PKS 1830-211.

Fluxes are in the unit of photons/cm^2/s above 100 MeV. All uncertainties are statistical only.

Note. All the flux reported above are by 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:
- S. Ciprini (stefano.ciprini[at]asdc.asi.it) for generic information related to this week
- Contact persons on this page for individual sources cited above.


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 (elisa.antolini@fisica.unipg.it) or D. Gasparrini (dario.gasparrini@asdc.asi.it) for generic information related to this week
- Contact persons on this page for individual sources cited above.

Monday, March 11, 2013

Fermi LAT Weekly Report N. 247



Covered period: 2013.Feb.25 - 2013.Mar.03
LAT Mission week: 247.57 - 248.57

  • The daily averaged gamma-ray flux from the Crab Nebula region reached (8.3+/-0.7) on March 3 which is a factor of 3 greater than its average 2FGL flux (see ATel#4855). This triggered pointed TOO observations by Fermi LAT starting on March 4.
  • PKS 0502+049 was detected in a flaring state on March 2 with a daily averaged flux of (1.0+/-0.2) (see ATel#4858).
  • Following the announcement by the AGILE team (ATel#4842) of the possible detection of a new unidentified gamma-ray source (AGL J1647+5107) the LAT data for the same sky position and time period were checked. Preliminary analysis revealed no detection above 100 MeV by Fermi LAT as well as no visible photon-excess in the count map region around the specified position.
  • A modest increase in flux was detected from the Sun on March 1 with a daily averaged flux of (0.6+/-0.2). No corresponding signs of activity were noticed on the 3-day GOES Proton Flux Monitor.
  • PKS 1424-418 was detected every day except Feb 25 with daily averaged flux between (1.1+/-0.3) and (1.8+/-0.3).
  • MG1 J123931+0443 was detected on February 28 and March 1 with daily averaged fluxes (1.1+/-0.4) and (0.7+/-0.2), respectively.
  • Sporadic daily detections of blazars and other AGN (fluxes below 1): 4C 38.41, NGC 1275, Mrk 421.
  • 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:
    - Roopesh Ojha (Roopesh.Ojha[at]gmail.com) for generic information related to this week
    - Contact persons on this page for individual sources cited above.