Fermi LAT Weekly Report N. 223

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Covered period: 2012.September.10 - 2012.September.16
LAT Mission week: 223.57 - 224.57

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• The gravitationally lensed blazar S3 0218+35 had a daily flux of (1.0±0.2) X 10^-6 on Sep 10 before fading away and was not detected for three days. It brightened again and was strongly detected the last three days of the week with daily flux in the range (1.4 - 3.8) X 10^-6 with the peak on Sep 15. This blazar has been very active recently with an initial flare-up (ATel#4343) and a possible echo (ATel#4361) reported recently. This could represent a new flare and a Fermi TOO to observe another possible echo around Sep 25 is planned.
• 4C 38.41 brightened from (0.8±0.2) X 10^-6 on Sep 10 to (1.8±0.3) X 10^-6 on Sep 15 before declining to (1.1±0.2) X 10^-6 on September 16.
• Apart from a dip down to (0.3±0.1) X 10^-6 on Sep 11, S5 0716+71 stayed at about 1 X 10^-61e-6 for the first five days of this week but was not detected on the last two days.
• B3 1343+451 was detected on Sep 10 through Sep 15, with a daily flux between (0.5±0.1) X 10^-6 and (0.8±0.2) X 10^-6.
• PKS 1424-418 was detected on Sep 10, 12 and 16 with a daily flux of (0.9±0.3) X 10^-6, (1.0±0.4) X 10^-6 and (0.7±0.2) X 10^-6, respectively.
• Mkn 421 was detected on September 10, 12, and 16 with daily flux between (0.4±0.1) X 10^-6 and (0.6±0.2) X 10^-6.
• PKS 0116-219 was detected on Sep 12, 13, and 16 with daily flux between (0.5±0.1) X 10^-6 and (0.7±0.2) X 10^-6.
• Sporadic daily detections of blazars (fluxes below 1 X 10^-6 ): PKS 2326-502 (Sep 10, 12), PG 1553+113 (Sep 11), PKS 0250-225 (Sep 14), B2 0716+33 (Sep 13), PKS 2155-304 (Sep 15).

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:
- R. Ojha (roopesh.ojha[at]gmail.com) for generic information related to this week
- Contact persons on this page for individual sources cited above.

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Fermi LAT weekly report N. 222

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Covered period: 2012.September.03 - 2012.September.09
LAT Mission week: 222.57 - 223.57

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• The gravitationally lensed blazar S3 0218+35 re-brightened on September 3, with a daily flux of (1.0±0.2) X 10^-6, reaching its maximum on September 6, with a daily flux of (2.4±0.3) X 10^-6. This flaring activity possibly represents the gravitational lens time delayed counterpart of the previous flaring event that started on August 25. See ATel#4361. The source continued to be detected on September 7, and 9 with a daily flux of (1.0±0.2) X 10^-6 and (1.2±0.3) X 10^-6, respectively. See ATel#4371.
• Mkn 421 detected on September 3, 4, 5, 7, 8, and 9, with a daily flux between (0.2±0.1) X 10^-6 and (0.5±0.2) X 10^-6.
• B3 1343+451 detected on September 3, 4, 5, 6, 7, and 9, with a daily flux between (0.4±0.1) X 10^-6 and (0.9±0.2) X 10^-6.
• 4C 38.41 detected on September 3, 5, 7, and 8, with a daily flux between (0.5±0.2) X 10^-6 and (0.9±0.2) X 10^-6.
• S5 0716+714 detected on September 6, 7, 8, and 9, with a daily flux between (0.4±0.1) X 10^-6 and (1.1±0.2) X 10^-6.
• PKS 1124-186 detected on September 3, and 4, with a daily flux of (0.5±0.2) X 10^-6.
• PKS 2233-148 detected on September 6, and 9, with a daily flux of (0.5±0.2) X 10^-6 and (0.4±0.1) X 10^-6, respectively.
• Sporadic daily detections of blazars (fluxes below 1 X 10^-6 ): PKS 0250-225 (September 3), 1H 1013+498 (September 3), S4 0954+65 (September 4), PKS 2326-502 (September 7), PKS 1424-418 (September 9).

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:
- M. Giroletti (giroletti[at]ira.inaf.it) and M. Orienti (orienti[at]ira.inaf.it) for generic information related to this week
- Contact persons on this page for individual sources cited above.

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Fermi LAT weekly report N.221

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Covered period: 2012.Aug.27 - 2012.Sep.02
LAT Mission week: 221.57 - 222.57

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• Mkn 421 and B3 1343+451 were detected almost all week long with flux in the range 0.4-0.7 X 10-6 and 0.5-1.0 X 10-6, respectively.
• Four other sources were detected at least in 3 days of the week with some trend in brightness. The flux decreased from 2.1 to 0.5 X 10-6 for PKS 1510-08 and from 0.9 to 0.5 X 10-6 for PKS 2233-148. On the contrary, the flux increased from 0.4 to 0.7 X 10-6 for 4C +38.41 and from 0.6 to 0.9 X 10-6 for PKS B1424-418.
• Sporadic activity (fluxes above 1.0 X 10-6) was observed from S4 0218+35 (1.7 on Aug. 27) and 3C 273 (1.9 on Aug. 31).
• Sporadic activity (fluxes below 1.0 X 10-6) was observed from BL Lacertae (0.5 and 0.8 on Aug. 27 and 28), PKS 2326–502 (0.4 and 0.7 on Aug. 28 and 30), PKS 0250-225 (0.4 on Aug. 30), PKS 0405-385 (0.4 on Aug. 31), PKS 0537-441 (0.2 on Sep. 02), B2 0716+33 (0.3 on Sep. 01), and 1H 1013+498 (0.1 on Sep. 01).

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:
- D. Donato (donato[at]milkyway.gsfc.nasa.gov) for generic information related to this week
- Contact persons on this page for individual sources cited above.

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Fermi LAT weekly report N. 220

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Covered period: 2012.Aug.20 - 2012.Aug.26
LAT Mission week: 220.57 - 221.57

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• First gamma-ray flare of the high redshift BL Lac object PKS2131-021 (z=1.284). The source reached a level of 0.6E-6 (about 30 times greater than the average flux reported in the second Fermi LAT catalog) on August 21. See ATel#4333 for more details. 
• Bright gamma-ray flare from the gravitationally lensed blazar S3 0218+35 (also known as B2 0218+35, OD 330, lens B0218+357,z=0.944+/-0.002). S3 0218+35 was active in gamma-rays all week, peaking at a daily flux level of about 1.6 and 1.7E-6 respectively on August 26 and 27. The source is lensed by aspiral galaxy at z=0.6846, it possesses one of the smallest Einstein rings in the radio band (0''.33 diameter) and is an important object for studies of gravitational lensing, Hubble constant value and individual molecular clouds at high redshifts. The time delay between the variations in the two compact radio source images is 10.5+/-0.4 days. See ATel#4343 for more details.
• Several blazars detected in flaring state during this week.
• BL Lacertae peaked with daily flux about 1.9E-6 on August 25and was above the 1E-6 level most days of the week. 
• PKS 1830-211 peaked with daily flux about 1.4E-6 on August 21.
• The high redshift blazar B3 1343+451 (z=2.534) was detected with daily flux of about 1E-6 on August 26.
• PKS 1510-089 and NRAO 676 were both detected at a daily flux level of 1E-6 on August 23.
• Enduring activity from Mkn 421 was detected the entire week. The source peaked at a daily flux level of 0.6E-6 on August 21,22 and 26.
• S5 0716+71 and 4C 38.41 (B2 1633+38) are active and detected all week above the 0.6E-6 level.
• PKS 2326-502, PKS 1424-41, PKS 2233-148, PKS 0454-234, are other blazars observed above the 0.5E-6 level in some days of the week. 
• Sporadic daily detections of blazars, with a daily flux level below about 0.5E-6: NGC 1275, PKS 0537-441, Mkn 501

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.

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Fermi LAT weekly report N. 219

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Covered period: 2012.Aug.013 - 2012.Aug.19
LAT Mission week: 219.57 - 220.57

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• A gamma ray source in the vicinity of PMN J1626--2426 reached a flux 1.0 X 10^-6. An Atel was issued In response to this event see ATel#4325.
• PKS 1424-418 bright in the beginning of this week with a flux around 1 X 10^-6 and then decreased to 0.4 X 10^-6 at the end of the week.
• Mrk 421 detected everyday this week peaking at 1.3 X 10^-6 on August 17.
• S5 0716+71 bright this week with flux peaking at 1.4 X 10^-6 on August 17
• NRAO 676 , PKS 2326-502 also bright this week with fluxes peaking around 1.0 X 10^-6
• CTA 102, B3 1342+451, PKS 0537-441, OG 050, 3C 66A, PKS 0244-470, 1633+382, PKS 2233-148, 4C +38.41, 3C 279, BL Lac , PMN J2345-1555 detected in one or two days of the week (flux below 1 X 10^-6 ).

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:
- M. Dutka (ditko86[at]gmail.com) for generic information related to this week
- Contact persons on this page for individual sources cited above.

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Fermi LAT weekly report N.218

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Covered period: 2012.Aug.6 - 2012.Aug.12
LAT Mission week: 218.57 - 219.57

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• S5 0716+71 is detected most of the week with daily flux in the range 0.2-0.7 X 10-6.
• PKS 1424-418 is detected every day this week with daily flux around 1.6 X 10^-6
• Mkn 421 detected every day this week reaching a peak flux of 1.0 X 10^-6 on Aug 10 2012, continuing the high activity already reported in Atel #4261
• PKS 1830-211 detected every day this week reaching a peak flux of 1.7 X 10^-6 on Aug 11 2012
• PKS 0244-470 detected every day this week but below the threshold of 1.0 X 10^-6
• PKS 2326-502, NRAO 676,OG 050, 3C 66A, SBS 0846+513, PKS 2155-304, B3 1343+451,PKS 1510-08,PKS 2233-148, NGC 1275, B2 1415+36, PKS 0906+01 detected once or twice during the week (flux below 1 X 10^-6 ).

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:
- D. Gasparrini (gasparrini[at]asdc.asi.it) for generic information related to this week
- Contact persons on this page for individual sources cited above.

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Fermi LAT weekly report N.217

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Covered period: 2012.Jul.30 - 2012.Aug.05
LAT Mission week: 217.57 - 217.57

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• Four sources were detected every day of the week: S5 0716+71, Mkn 421, PKS 2233-148, and PKS B1424-418. The flux of S5 0716+71 was 0.7 X 10-6, but peaked just above 1.0 X 10-6 on Aug. 2 and 3; Mkn 421 and PKS 2233-148 showed a constant behavior with the daily flux in the range 0.4-0.6 X 10-6 and 0.5-0.8 X 10-6, respectively; PKS B1424-418 was seen more variable with flux flickering between 0.8 and 1.5 X 10-6.
• PKS 2326-502 was detected in the first 4 days of the week with daily flux in the range 0.6-0.8 X 10-6.
• Sporadic activity (fluxes below 1.0 X 10-6) observed from 4C +21.35 (0.4 on Jul. 31), 4C +38.41 (0.9 on Aug. 3), PKS 0244-470 (0.7 on Jul. 31 and Aug. 5), PKS 0735+17 (0.2 on Jul. 30), CTA 102 (0.5 on Jul. 30 and 0.8 on Aug. 1), PG 1246+586 (0.2 on Aug. 5), PKS 1424+240 (0.3 on Aug. 3), PKS 2155-304 (0.1 on Aug. 4), and PKS 2255-282 (0.4 on Jul. 31).

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:
- D. Donato (donato[at]milkyway.gsfc.nasa.gov) for generic information related to this week
- Contact persons on this page for individual sources cited above.

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