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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"

3758 results found.

  1. Fermi-GBM Observations of Recent Bursting Activity from SGR J1935+2154
  2. Fermi GRB 220111A: Global MASTER-Net observations report
  3. Konus-Wind detection of GRB 220101A
  4. Fermi trigger No 663406755: Global MASTER-Net observations report
  5. GRB 220107A: AbAO and Terskol optical observations
  6. GRB 211227A: Deep early CAHA 2.2m/CAFOS observation
  7. Fermi GRB 211229A: Global MASTER-Net observations report
  8. Konus-Wind detection of the intermediate flare from SGR 1935+2154
  9. GRB 211227A: Liverpool Telescope upper limits
  10. GRB 211227A: LCO Optical Observations
  11. GRB 211227A: MAXI/GSC detection
  12. GRB 211225A: MITSuME Akeno optical upper limits
  13. Swift GRB 211225B: Global MASTER-Net observations report
  14. Fermi GRB 211225C: Global MASTER-Net observations report
  15. GRB 211225A/MAXI J0827-071: MAXI/GSC detection
  16. GRB 211218A: MITSuME Akeno optical upper limits
  17. GRB 211218A, MAXI J0909-041: MAXI/GSC detection
  18. MAXI GRB211218.04: Global MASTER-Net observations report
  19. GRB 211212A: Fermi GBM Final Real-time Localization
  20. Fermi GRB 211211B: Global MASTER-Net observations report
  21. Fermi trigger No 660736561: Global MASTER-Net observations report
  22. Fermi GRB 211204A: Global MASTER-Net observations report
  23. Fermi GRB 211130A: Global MASTER-Net observations report
  24. GRB 211129A: Swift/UVOT Upper Limits
  25. IceCube-Cascade 211128A: Upper limits from a search for additional neutrino events in IceCube
  26. IPN triangulation of GRB 211120A
  27. Fermi trigger No 658971499: Global MASTER-Net observations report
  28. Fermi trigger No 658755664: Global MASTER-Net observations report
  29. GRB 211115A: MAXI/GSC detection
  30. Fermi trigger No 658214822: Global MASTER-Net observations report
  31. Fermi GRB 211109B: Global MASTER-Net observations report
  32. GRB 211023A: SAO RAS optical observations
  33. Swift Trigger 1082569 is probably not a GRB
  34. GRB 211023B: Subaru optical observation
  35. GRB 211024A: MITSuME Akeno optical observation
  36. GRB 211023B: MITSuME Akeno optical upper limits
  37. Fermi GRB 211031A: Global MASTER-Net observations report
  38. GRB 211023A: 1.3m DFOT Optical Observations
  39. GRB 211023A: Terskol optical observations
  40. Fermi GRB 211027A: Global MASTER-Net observations report
  41. GRB 210610B: Sintesz-Newton/CrAO optical observations
  42. GRB 211023B: BOOTES-4/MET and 1.5m OSN optical upper limit
  43. GRB 211018A: Fermi GBM observation
  44. GRB 211018A: Fermi-LAT detection
  45. Fermi trigger No 655401471: Global MASTER-Net observations report
  46. Fermi trigger No 654854799: Global MASTER-Net observations report
  47. GRB 210928A: Fermi GBM observation
  48. GRB 210927A: GIT optical follow-up of ZTF21acdwctm.
  49. Fermi GRB 210929B: Global MASTER-Net observations report
  50. GRB 210919A OSN 1.5m Source Confirmation
  51. IceCube Alert 210922.76: Global MASTER-Net observations report
  52. GRB 210919A: Swift detection of a short burst
  53. Konus-Wind observation of the recent SGR 1935+2154 activity
  54. Fermi GBM observation of another bright burst in the direction of SGR 1935+2154
  55. GECAM observations of bursts from SGR J1935+2154 (2021-09-11T07 to 2021-09-12T08)
  56. Fermi trigger No 653084584: Global MASTER-Net observations report
  57. Fermi trigger No 653083551: Global MASTER-Net observations report
  58. Fermi trigger No 653066130: Global MASTER-Net observations report
  59. Fermi trigger No 653022153: Global MASTER-Net observations report
  60. IPN triangulation of a bright burst from SGR 1935+2154
  61. Fermi trigger No 652944960: Global MASTER-Net observations report
  62. Fermi trigger No 652906639: Global MASTER-Net observations report
  63. Fermi trigger No 652585475: Global MASTER-Net observations report
  64. Fermi GRB 210903A: Global MASTER-Net observations report
  65. GRB 210827A: BOOTES-5/JGT optical upper limit
  66. Integral GRB210829.14: Global MASTER-Net observations report
  67. Fermi GRB 210827A: Global MASTER-Net observations report
  68. GRB 210824A: Fermi GBM Observation
  69. GRB 210822B: DDOTI Upper Limits on the Afterglow
  70. Fermi GRB 210822B: Global MASTER-Net observations report
  71. Fermi GRB 210821A: Global MASTER-Net observations report
  72. GRB 210821A: Fermi GBM Final Real-time Localization
  73. Fermi trigger No 651110719: Global MASTER-Net observations report
  74. Fermi GRB 210813A: Global MASTER-Net observations report
  75. GRB 210807A: Tautenburg observations
  76. GRB 210807A: Swift-BAT refined analysis
  77. GRB 210807C: Fermi GBM detection
  78. Fermi GRB 210807C: Global MASTER-Net observations report
  79. Swift GRB 210807A: Global MASTER-Net observations report
  80. IPN Triangulation of a bright burst from SGR 1935+2154
  81. Fermi trigger No 649814537: Global MASTER-Net observations report
  82. GRB 210731A: MeerLICHT optical afterglow detection
  83. GRB210731A: Enhanced Swift-XRT position
  84. Fermi trigger No 648959581: Global MASTER-Net observations report
  85. Fermi trigger No 648868114: Global MASTER-Net observations report
  86. Swift GRB210724.84: Global MASTER-Net observations report
  87. Fermi trigger No 648602917: Global MASTER-Net observations report
  88. Fermi trigger No 648278666: Global MASTER-Net observations report
  89. GRB 210715B: DDOTI Upper Limits on the Afterglow
  90. Fermi trigger No 647942198: Global MASTER-Net observations report
  91. Fermi trigger No 647805873: Global MASTER-Net observations report
  92. Fermi trigger No 647641569: Global MASTER-Net observations report
  93. Fermi trigger No 647624281: Global MASTER-Net observations report
  94. Fermi GRB 210709A: Global MASTER-Net observations report
  95. GRB 210708B: Swift detection of a possible burst
  96. Fermi trigger No 647365516: Global MASTER-Net observations report
  97. Integral GRB210707.02: Global MASTER-Net observations report
  98. Fermi trigger No 647108723: Global MASTER-Net observations report
  99. Fermi trigger No 647120009: Global MASTER-Net observations report
  100. GRB210702A: MeerLICHT multi-colour photometry

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