Fermi Gamma-Ray Sky

Tuesday, January 26, 2010

Extra note - Jan. 26, 2010

About the source reported in AGILE's ATel#2403

In ATel #2403 a possible AGILE detection of a new gamma-ray source (AGL J2206+6203) is announced. For the sky position and time interval reported in this ATel preliminary checks and analysis find no detection above 100 MeV by Fermi LAT. No hint of a signal in the 0.1-1 GeV energy band is found (TS=0), as well as no photon-count excess visible in the counts map region around the specified coordinates. Further analysis is ongoing.

For questions and comments you can contact the Flare Advocate on shift (S. Ciprini (stefano.ciprini[at]pg.infn.it) ), and both E. Hays (elizabeth.a.hays[at]nasa.gov) and A. Hill (Adam.Hill[at]obs.ujf-grenoble.fr).

Tuesday, January 5, 2010

Fermi LAT weekly report N.79

Covered period: 2009.Dec.7 - 2009.Dec.12

LAT Mission week: 79.57 - 80.57

3C353.4 still flaring, decreased in the daily flux from ~16E-6 to ~8E-6 over the course of the week.

4C38.41 active at the beginning of the week, detected at a daily flux of 1.8E-6 on Dec 9th.

3C273 slightly bright, detected on the 10th Dec at a daily run of 1.6E-6.

PKS 1510-08 was bright on two days, reaching a daily flux of 3E-6 on Dec 13th.

PKS 1222+21 was active this week reaching a flux of 1.1E-6 towards the end of the week.

The FSRQ TEX 0322+222 was detected at a daily flux of 1.4E-6 on Dec 8th.

Fluxes are in the unit of 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:

- A. Cannon (annacannon1984@gmail.com) for generic information related to this week

- Contact persons on this page for individual sources cited above.

Monday, January 4, 2010

Fermi LAT weekly report N.81

Covered period: 2009.Dec.21 - 2009.Dec.27

LAT Mission week: 81.57 - 82.57

4C 21.35 (PKS 1222+21) bright also this week (above 1E-6 in the first part of the week).

PKS 1510-089 is active (daily flux above 1E-6 in most days of the week).

Mkn 421 detected most of the days.

Very bright 3C 454.3 also this week (weekly averaged flux level around 3.5E-6).

PKS 1424-41 and PKS 0805-07 detected at the end of the week.

Nothing bright and significant is preliminary detected above 100 MeV at the position reported in the AGILE's ATel#2361 (l=273.1, b=16.5).

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

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]pg.infn.it) for generic information related to this week

- Contact persons on this page for individual sources cited above.

Fermi LAT weekly report N.80

Covered period: 2009.Dec.14 - 2009.Dec.20

LAT Mission week: 80.57 - 81.57

The blazar 4C 21.35 (PKS 1222+21) showed a flare with daily flux above 3E-6 on Dec.15 (see ATel#2349).

PKS 1510-089 is back and increasing this week (daily flux reached about 2.7E-6 on Dec.18).

Mkn 421 was slightly more active being detected most of the days.

A enduring very bright 3C 454.3 for all the week (weekly averaged flux level around to 5E-6).

PKS 0537-441, and PKS 0805-07 were more active at the end of the week.

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

Tuesday, December 15, 2009

Fermi LAT weekly reports N.78

Covered period: 2009.Nov.30 – 2009.Dec.6 (UT)

LAT Mission week: 78.57 – 79.57

A very interesting week for LAT blazars with the detection of a giant GeV flare from the FSRQ 3C 454.3.

3C 454.3 (LAT Atel #2328) : continued to the previous week's flare and reached a very high state with an average daily gamma-ray flux of 22 ± 1, peaking at 26 ± 3 in the 6 hour period between 12 and 18 UT of Dec. 2nd. This flare is the highest ever recorded in this energy range and represents more than twice the flux of the Vela pulsar, the brightest persistent source in the gamma-ray sky.
See the NASA press release http://www.nasa.gov/mission_pages/GLAST/news/brightest-blazar.html
From Dec. 2nd the flux slightly decreased almost continuously but ended the week on Dec. 6 with daily flux = 14 ± 1.

GB6 B1310+4844 (GB1 1310+487) (LAT ATels #2306, #2316) : remained in high state until Dec. 2nd with flux = 0.6 +/- 0.2 and index = 2.0 +/- 0.2 and was not detected after this day.

4C +14.23 began less active than last week with flux = 1.0 +/- 0.4 on Nov. 30 but the flux then increased to 1.9 +/- 0.5 on Dec. 1St . The source finished the week with flux = 1.4 +/- 0.4 on Dec. 4.

PKS 1222+21 was detected on Dec 1st and Dec. 4 at a similar level to last week reaching flux = 0.8 +/- 0.2.

3C 273 appeared once during the week on Dec. 2nd with daily flux = 1.8 +/- 0.4.

PKS 0426-38 appeared on Nov. 30 with flux = 0.3 +/- 0.1 and reached flux = 0.8 +/- 0.2 on Dec. 1st.

4C +38.41 was detected on Dec. 4 with flux = 0.7 +/- 0.2.

PKS 0537-441 appeared at the end of the week, on Dec. 5, with flux = 0.7 +/- 0.3.

Fluxes are in the unit of 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:

- S. Ciprini (escande[at]cenbg.in2p3.fr) for generic information related to this week

- Contact persons on this page for individual sources cited above.

Saturday, December 5, 2009

Fermi LAT weekly report N.77

Covered period: 2009.Nov.23 - 2009.Nov.29

LAT Mission week: 77.57 - 78.57

Another good week for gamma-ray blazars with the detection of a spectrally hard flare from the FSRQ, GB6 B1310+4844, and record breaking activity in the LAT from 3C 454.3. Several of last week's active sources have faded (B2 1520+31, PKS 1622-253, PKS 1510-089).

GB6 B1310+4844 (GB1 1310+487, LAT ATels #2306, #2316) continued the previous week's flare and peaked on Nov. 27 with daily flux=(2.5 ± 0.4) x 10^-6. The spectrum exhibited significant hardening during the flare with a daily photon index for Nov. 26 of 1.8 ± 0.1. This is harder than any of the average photon indices found for FSRQs in the LAT bright AGN sample (Abdo et al., 2009, ApJ, 700, 597).

3C 454.3 became more active and surpassed previous gamma-ray flux levels on Nov. 28 at daily flux=(8.7 ± 0.9) x 10^-6. It ended the week on Nov. 30 with daily flux=(9.2 ± 0.8) x 10^-6. (The weekly average flux is also high at (6.6 ± 0.3) x 10^-6).

4C +14.23 (PKS 0722+145, LAT ATel #2243) was active at a similar level to last week reaching daily flux=(1.8 ± 0.6) x 10^-6 on Nov. 27. The source has since faded below threshold.

PKS 1222+216 (LAT ATel #2021) appeared on Nov. 24 with daily flux=(0.9 ± 0.3) x 10^-6 and continued at this level through Nov. 28.

4C +38.41 matched previous days on Nov. 23 with flux=(0.7 ± 0.2) x 10^-6. This is a mild rebrightening of a recently reported high redshift blazar (ATel #2136)

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

Note. All the fluxes reported above are from 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:

- Elizabeth Hays (elizabeth.a.hays[at]nasa.gov) for generic information related to this week

- Contact persons on this page for individual sources cited above.

Thursday, December 3, 2009

Fermi LAT weekly report N.76

Covered period: 2009.Nov.16 - 2009.Nov.22 (UT)

LAT Mission week: 76.57 - 77.57

The gamma-ray sky showed some exciting activity this week, with five blazars exceeding the 1⋅10^-6 flux above 100 MeV that defines flaring and a surprise detection of the quasar GB6 B1310+4844.

On Nov. 18, GB6 B1310+4844 (LAT ATels #2306, #2316) attracted attention by the detection of a GeV flare consistent with the position of this source (daily flux: (1.0±0.2)⋅10^-6). It remained bright ending the week with an even higher daily flux of (2.2±0.2)⋅10^-6 on Nov. 22.
(LAT contact: K. Sokolovsky, ksokolov[at]mpifr-bonn.mpg.de)

4C +14.23 (PKS 0722+145, LAT ATel #2243) stays bright above 1⋅10^-6. It faded intermittently during the middle of the week and re-brightened to a daily flux level of (1.8±0.4)⋅10^-6 (average weekly flux: (1.5±0.1)⋅10^-6).

Rapid brightening of 3C 454.3 toward the second half of the week, peaking at a daily flux level of (5.7±0.7)⋅10^-6 on Nov 20 (weekly average flux: (3.7±0.2)⋅10^-6).

On Nov. 17, B2 1520+31 (LAT ATel #2026) showed a weak flare (daily flux: (0.9±0.3)⋅10^-6), faded and re-appeared even stronger (Nov. 19 - Nov. 21), peaking on Nov. 21 (daily flux: (1.5±0.3)⋅10^-6).

On Nov. 17, PKS 1622-253 (LAT ATel #2231) flared. (daily flux: (1.9±0.7)⋅10^-6, weekly flux: (0.5±0.2)⋅10^-6).

On Nov. 17, PKS 1510-089 (LAT ATel #2033) flared as well. (daily flux: (1.2±0.4)⋅10^-6, weekly flux: (0.8±0.2)⋅10^-6).

4C +38.41 (LAT ATel #2136) was brightening during Nov. 21 (daily flux: (0.7±0.2)⋅10^-6) and was detected at the same level during Nov. 22.

Fluxes are in the unit of photons/cm^2/s above 100 MeV. Errors 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:

- F. Schinzel (schinzel[at]mpifr-bonn.mpg.de) for generic information related to this week

- Contact persons on this page for individual sources cited above.