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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

4253 results found.

  1. LIGO/Virgo S200105ae: Global MASTER-Net observations report
  2. GRB 200105A: MAXI/GSC detection
  3. Fermi trigger No 599761015: Global MASTER-Net observations report
  4. IceCube Alert 200101.46: Global MASTER-Net observations report
  5. IPN triangulation of GRB 191227B (short)
  6. Konus-Wind observation of GRB 191221B
  7. LIGO/Virgo S191222n : No significant candidates in FRAM-TAROT-GRANDMA observations
  8. LIGO/Virgo S191222n: no counterpart candidate in SVOM/GWAC observations
  9. LIGO/Virgo S191216ap: No significant candidates found in Pan-STARRS observations
  10. LIGO/Virgo S191222n: Upper limits from IceCube neutrino searches
  11. LIGO/Virgo S191216ap : No significant candidates in FRAM-TAROT-GRANDMA observations
  12. Fermi trigger No 598543714: Global MASTER-Net observations report
  13. GRB 191220A: Swift detection of a burst
  14. LIGO/Virgo S191216ap: AstroSat CZTI upper limits
  15. LIGO/Virgo S191213g: No counterpart candidate in the NOWT observations
  16. LIGO/Virgo S191216ap: GRAWITA Loiano observations of HAWC error region
  17. LIGO/Virgo S191215w : No significant candidates in TAROT - FRAM - GRANDMA observations.
  18. LIGO/Virgo S191216ap: 1 counterpart neutrino candidate from IceCube neutrino searches
  19. LIGO/Virgo S191215w: AstroSat CZTI upper limits
  20. LIGO/Virgo S191215w: Global MASTER-Net observations report
  21. LIGO/Virgo S191215w: Upper limits from IceCube neutrino searches
  22. LIGO/Virgo S191213g: AstroSat CZTI upper limits
  23. LIGO/Virgo S191213g: Candidates from the Zwicky Transient Facility
  24. LIGO/Virgo S191213g: Upper limits from IceCube neutrino searches
  25. LIGO/Virgo S191205ah: Gaia Photometric Alerts transient candidates
  26. LIGO/Virgo S191205ah : No significant candidates in FRAM - TAROT – GRANDMA observations
  27. LIGO/Virgo S191205ah: AstroSat CZTI upper limits
  28. LIGO/Virgo S191205ah: Pan-STARRS1 previous detections of SAGUARO transient
  29. LIGO/Virgo S191129u : No significant candidates in FRAM-TAROT-GRANDMA observations.
  30. LIGO/Virgo S191204r: No significant candidates in FRAM-TAROT-GRANDMA observations.
  31. LIGO/Virgo S191205ah: Upper limits from IceCube neutrino searches
  32. LIGO/Virgo S191204r: Upper limits from IceCube neutrino searches
  33. LIGO/Virgo S191129u: No transient candidates in CALET observations
  34. LIGO/Virgo S191129u: Upper limits from Insight-HXMT/HE observations
  35. GRB 191129A: AstroSat CZTI detection
  36. LIGO/Virgo S191129u: No counterpart candidates in Fermi-LAT observations
  37. LIGO/Virgo S191129u: Coverage and upper limits from MAXI/GSC observations
  38. LIGO/Virgo S191129u: upper limits from AGILE/GRID observations
  39. LIGO/Virgo S191129u : no neutrino counterpart candidate in ANTARES search
  40. LIGO/Virgo S191129u: upper limits from AGILE/MCAL observations
  41. LIGO/Virgo S191129u: Upper limits from IceCube neutrino searches
  42. LIGO/Virgo S191129u: Global MASTER-Net observations report
  43. LIGO/Virgo S191129u: Identification of a GW compact binary merger candidate
  44. Fermi trigger No 596690552: Global MASTER-Net observations report
  45. GRB 191129A: Fermi GBM Final Real-time Localization
  46. Fermi trigger No 596387570: Global MASTER-Net observations report
  47. LIGO/Virgo S191124be: Global MASTER-Net observations report
  48. IceCube-191119A: No significant detection in HAWC
  49. IceCube-191119A - No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  50. Konus-Wind observation of the recent SGR 1935+2154 activity
  51. LIGO/Virgo S191109d: Not observable by CALET
  52. GRB 191111A: Fermi GBM Final Real-time Localization
  53. LIGO/Virgo S191110af: Upper limits from IceCube neutrino searches
  54. LIGO/Virgo S191105e: No significant candidates in FRAM-TAROT-GRANDMA observations
  55. LIGO/Virgo S191109d: AstroSat CZTI upper limits
  56. LIGO/Virgo S191109d: Upper limits from IceCube neutrino searches
  57. LIGO/Virgo S191105e: AstroSat CZTI upper limits
  58. LIGO/Virgo S191105e: Global MASTER-Net observations report
  59. LIGO/Virgo S191105e: Upper limits from IceCube neutrino searches
  60. Swift trigger 933276 MASTER observation
  61. Fermi trigger No 594592184: Global MASTER-Net observations report
  62. Trigger 933285: Swift detection of the brightest burst so far from SGR 1935+2154
  63. Trigger 933276: Swift detection of further activity from SGR 1935+2154
  64. Fermi GBM GRB 191104C (trigger 594592184 / 191104854) is not a GRB
  65. GRB 191104C: Fermi GBM Final Real-time Localization
  66. Fermi GBM GRBs 191104 A, B, C and triggers 594534420/191104185 and 594563923/191104527 are not GRBs
  67. SGR 1935+2154: Swift-BAT refined analysis
  68. GRB 191104B/GRB 191104C are SGR 1935+2154
  69. Trigger 933083: Swift detection of SGR 1935+2154
  70. Fermi GBM triggers 594523229/191104056 and 594528816/191104120 are not GRBs
  71. GRB 191028B: MASTER optical observation
  72. GRB 191029A: iTelescope optical upper limits
  73. GRB191024A: MASTER optical observation
  74. Swift GRB191020.81: Global MASTER-Net OT detection
  75. Fermi trigger No 593176520: Global MASTER-Net observations report
  76. Fermi trigger No 593045905: Global MASTER-Net observations report
  77. ANTARES 191011A: MASTER optical observation befor and after trigger
  78. TESS Detection of the Optical Emission from the Possible Untriggered GRB Associated with ZTF19abvizsw
  79. Fermi/GBM observation of a bright burst from magnetar SGR 1935+2154
  80. LIGO/Virgo S190930s: no counterpart candidate in the SVOM/GWAC observations
  81. IceCube-191001A: HAWC follow-up
  82. LIGO/Virgo S190930t: Candidates from ATLAS observations and constraints on AT2019rpr and AT2019rpn
  83. LIGO/Virgo S190930s: No counterpart candidates in KAIT observations
  84. GRB 191001A: DDOTI Optical Counterpart Candidate
  85. LIGO/Virgo S190930t: Candidates from the Zwicky Transient Facility
  86. Fermi trigger No 591604915: Global MASTER-Net observations report
  87. LIGO/Virgo S190930t: Upper limits from IceCube neutrino searches
  88. LIGO/Virgo S190930s: Upper limits from IceCube neutrino searches
  89. LIGO/Virgo S190930s: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  90. GRB 190928A: MASTER optical observations
  91. Fermi trigger No 591391412: Global MASTER-Net observations report
  92. LIGO/Virgo S190923y: No significant candidates in TAROT-GRANDMA observations
  93. LIGO/Virgo S190924h: Upper limits from IceCube neutrino searches
  94. LIGO/Virgo S190923y: Upper limits from IceCube neutrino searches
  95. Fermi trigger No 590899086: Global MASTER-Net observations report
  96. Fermi trigger No 590610007: Global MASTER-Net observations report
  97. LIGO/Virgo S190915ak: No significant candidates in TAROT-GRANDMA observations
  98. LIGO/Virgo S190910h: No significant candidates in TAROT-GRANDMA observations
  99. LIGO/Virgo S190915ak: Upper limits from IceCube neutrino searches
  100. LIGO/Virgo S190910d : No significant candidates in TAROT-GRANDMA observations

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