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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').
Advanced Search

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.

Advanced Search Examples (click to copy):

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

3392 results found.

  1. GRB 220921A: ATCA detection of radio counterpart
  2. Fermi trigger No 686403226: Global MASTER-Net observations report
  3. Fermi trigger No 686350260: Global MASTER-Net observations report
  4. Fermi-LAT gamma-ray observations of IceCube-220928A
  5. IceCube-220928A: Upper limits from a search for additional neutrino events in IceCube
  6. IceCube-220928A - IceCube observation of a high-energy neutrino candidate track-like event
  7. IPN triangulation of GRB 220927A (long)
  8. Fermi GRB 220925A: Global MASTER-Net observations report
  9. Fermi trigger No 685748699: Global MASTER-Net observations report
  10. LAT GRB220921.46: Global MASTER-Net observations report
  11. Fermi trigger No 685452089: Global MASTER-Net observations report
  12. Fermi trigger No 684716840: Global MASTER-Net observations report
  13. Fermi GRB 220912A: Global MASTER-Net observations report
  14. IPN triangulation of GRB 220905A
  15. IceCube Alert 220907.28: Global MASTER-Net observations report
  16. GRB 220905A: BALROG localization (Fermi Trigger 684070128 / GRB 220905478)
  17. GRB 220905A: Fermi GBM Final Real-time Localization
  18. Fermi trigger No 683646997: Global MASTER-Net observations report
  19. Fermi trigger No 683537972: Global MASTER-Net observations report
  20. Fermi trigger No 683202084: Global MASTER-Net observations report
  21. Fermi trigger No 683183601: Global MASTER-Net observations report
  22. GRB 220823A: Fermi GBM detection
  23. Fermi trigger No 682918137: Global MASTER-Net observations report
  24. GRB 220823A: Swift/BAT-GUANO detection of a short burst
  25. IceCube Alert 220822.85: Global MASTER-Net observations report
  26. Fermi GRB 220810A: Global MASTER-Net observations report
  27. Fermi trigger No 681212354: Global MASTER-Net observations report
  28. Fermi trigger No 680782656: Global MASTER-Net observations report
  29. Fermi GRB 220728A: Global MASTER-Net observations report
  30. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-220728A
  31. GRB 220728A: Fermi GBM Final Real-time Localization
  32. Fermi GRB 220724A: Global MASTER-Net observations report
  33. GRB 220715B: Fermi GBM detection
  34. GRB 220714B: Fermi GBM observation
  35. Fermi GRB 220711B: Global MASTER-Net observations report
  36. GRB 220711B: NOT optical observations
  37. GRB 220711B: Swift detection of a burst
  38. GRB 220711B: Fermi GBM Final Real-time Localization
  39. GRB 220708A: Swift detection of a burst
  40. GRB 220706A: Swift detection of a burst
  41. IceCube-220629A: Upper limits from a search for additional neutrino events in IceCube
  42. IceCube-220629A: No significant detection in HAWC
  43. IceCube-220627A: No significant detection in HAWC
  44. IceCube-220627A: Upper limits from a search for additional neutrino events in IceCube
  45. Swift XRT observations of WISEA J145820.77+412101.9 / IceCube 220624A
  46. GRB 220627A: MeerLICHT candidate optical afterglow
  47. GRB 220627A: Fermi GBM Detection of a possible Lensed or Ultra-long GRB
  48. Fermi trigger No 678058621: Global MASTER-Net observations report
  49. Fermi GRB 220623B: Global MASTER-Net observations report
  50. Swift Detection of MAXI J0655-013
  51. Fermi trigger No 677377371: Global MASTER-Net observations report
  52. Fermi GRB 220620A: Global MASTER-Net observations report
  53. GRB 220617A: Swift-XRT observations
  54. IPN triangulation of GRB 220606C
  55. Fermi trigger No 676909037: Global MASTER-Net observations report
  56. Fermi trigger No 676537486: Global MASTER-Net observations report
  57. Fermi GRB 220608A: Global MASTER-Net observations report
  58. Konus-Wind detection of GRB 220601A
  59. GRB 220606B: Swift/BAT-GUANO candidate arcminute localization of a short burst
  60. GRB 220606B: Fermi GBM Final Real-time Localization
  61. Fermi trigger No 675992935: Global MASTER-Net observations report
  62. GRB 220527A: MITSuME Akeno continued optical observation
  63. GRB 220527A: Lick 3m Optical Observations
  64. GRB 220528A: Fermi GBM Observation
  65. Fermi GRB 220530A: Global MASTER-Net observations report
  66. GRB 220528A: Fermi GBM Final Localization
  67. GRB 220527A: REM optical/NIR observations
  68. GRB 220527A: VLT/X-shooter spectroscopic redshift
  69. Fermi trigger No 675411172: Global MASTER-Net observations report
  70. GRB 220527A: NOT optical photometry and spectroscopic redshift
  71. IPN triangulation of GRB 220522B
  72. GRB 220521A: ISON-Castelgrande observatory optical observations
  73. IPN triangulation of GRB 220519A
  74. Konus-Wind detection of GRB 220506A
  75. GRB 220514B: MAXI/GSC detection
  76. IceCube-220513A: No Candidate Counterparts from the Zwicky Transient Facility
  77. IceCube Alert 220513.97: Global MASTER-Net observations report
  78. Fermi GRB 220513A: Global MASTER-Net observations report
  79. GRB 220506A: MITSuME Akeno optical upper limits
  80. IceCube Alert 220509.76: Global MASTER-Net observations report
  81. GRB 220506A/MAXI J1558-266: MAXI/GSC detection
  82. IceCube-220421A: Upper limits from a search for additional neutrino events in IceCube
  83. GRB 220423A: Detection by VZLUSAT-2
  84. Fermi GRB 220426B: Global MASTER-Net observations report
  85. Fermi trigger No 672374264: Global MASTER-Net observations report
  86. Fermi trigger No 671729344: Global MASTER-Net observations report
  87. Konus-Wind detection of GRB 220412B
  88. GRB 220408B: Fermi GBM observation
  89. Konus-Wind detection of GRB 220408B
  90. GRB 220412A: Continued RATIR Observations and Steepening of the Light Curve
  91. GRB 220408B: Fermi-LAT detection
  92. GRB 220412B: MITSuME Akeno optical upper limits
  93. IPN triangulation of GRB 220408B
  94. Fermi GRB 220411A: Global MASTER-Net observations report
  95. GRB 220408B: AstroSat CZTI detection
  96. GRB 220408A: BOOTES-5/JGT optical afterglow detection
  97. Fermi GRB 220408B: Global MASTER-Net observations report
  98. GRB 220408B: Fermi GBM Final Localization
  99. IceCube Alert 220405.93: Global MASTER-Net observations report
  100. IceCube Alert 220405.21: Global MASTER-Net observations report

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