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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

24494 results found.

  1. EP241021a: Upper limit from Konus-Wind observations
  2. GRB 241101A: Swift-BAT refined analysis
  3. GRB 241030A: Optical Observations via Virtual Telescope Project
  4. GRB 241101A: Swift detection of a burst
  5. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits
  6. Fermi trigger No 752083996: Global MASTER-Net observations report
  7. GRB 241030A: Fermi GBM Observation
  8. EP241021a: AMI-LA radio detection
  9. GRB 241030B: LCOGT Optical Upper Limits
  10. GRB 241030B: Swift-BAT refined analysis
  11. GRB 241030A: Swift-BAT refined analysis
  12. EP EP241030a: Global MASTER-Net observations report
  13. Fermi trigger No 752006065: Global MASTER-Net observations report
  14. Swift GRB241030.77: Global MASTER-Net observations report
  15. GRB 241030B: SVOM/GRM observation
  16. GRB 241030B : MITSuME Akeno optical upper limits
  17. GRB 241030B: SVOM/VT optical afterglow observations
  18. GRB241030B: Fermi GBM Observation
  19. GRB 241029A: SVOM/VT optical afterglow observations
  20. GRB 241030B: optical observations from the INAF Asiago Observatory
  21. GRB 241030A: Swift-XRT refined Analysis
  22. GRB 241030B: SVOM/ECLAIRs detection of a burst
  23. Konus-Wind detection of GRB 241030A
  24. GRB 241030B: Swift detection of a burst
  25. GRB 241030B: Fermi GBM Final Real-time Localization
  26. GRB 241030A: Fermi-LAT detection
  27. Fermi GRB 241030A: Global MASTER-Net observations report
  28. Swift GRB 241030A: Global MASTER-Net observations report
  29. GRB 241030A: SVOM/GRM observation
  30. GRB 241026A: Swift-BAT refined analysis
  31. GRB 241030A: SVOM/C-GFT optical observations
  32. GRB 241026A: LBT optical observations
  33. EP241021a: Optical rebrightening observations with Mephisto
  34. EP241026b: EP-FXT follow-up observation
  35. GRB 241030A: Multiband optical detection with Mephisto
  36. GRB 241030A : MITSuME Akeno optical afterglow detection
  37. GRB 241030A: Fermi GBM Final Real-time Localization
  38. GRB 241029A: Fermi GBM Observation
  39. GRB 241029A: MASTER early optical counterpart detection
  40. GRB 241029A: Mephisto observations
  41. EP 241026b: LBT possible optical counterpart (brightening source)
  42. GRB 241029A: TRT optical afterglow candidate detection
  43. GRB 241029A: SVOM/GRM observation
  44. GRB 241029A : Detection and localization of a bright long GRB by SVOM/ECLAIRs
  45. Fermi trigger No 751861204: Global MASTER-Net observations report
  46. GRB 241029A: Fermi GBM Final Real-time Localization
  47. GRB 241026A: the 100th GRB detected by GRBAlpha
  48. Konus-Wind detection of GRB 241025A
  49. GRB 241026A: GECAM detection
  50. GRB 241026A: SVOM/GRM observation
  51. GRB 241026A Fermi GBM Analysis
  52. EP241026a (GRB 241026A): EP on-board trigger and follow-up observation
  53. EP EP241026b: Global MASTER-Net observations report
  54. GRB 241026A: KAIT optical observations
  55. Fermi trigger No 751616906: Global MASTER-Net observations report
  56. Fermi GRB 241026A: Global MASTER-Net observations report
  57. GRB 241026A: Swift detection of a burst
  58. Swift GRB241026.95: Global MASTER-Net observations report
  59. GRB 241026A: Fermi GBM Final Real-time Localization
  60. GRB241025A: 1.3m DFOT optical afterglow detection
  61. EP241021a: optical follow-up observations with Xinglong Observatory
  62. GRB 241025C: Fermi GBM Detection
  63. GRB 241025A: Fermi GBM Observation
  64. IPN triangulation of GRB 241022A (short/hard)
  65. LIGO/Virgo/KAGRA S241009l: Upper limits from Swift/BAT-GUANO
  66. GRB 241025C: Fermi GBM Final Localization
  67. GRB 241025B: Fermi GBM Final Localization
  68. Fermi trigger No 751563375: Global MASTER-Net observations report
  69. Fermi trigger No 751554401: Global MASTER-Net observations report
  70. EP241021a: optical follow-up observations with the Liverpool Telescope
  71. Fermi GRB 241025A: Global MASTER-Net observations report
  72. Swift GRB 241025A: Global MASTER-Net observations report
  73. GRB 241001A: JWST spectroscopic identification of a supernova counterpart
  74. GRB 241025A: NOT spectroscopic redshift of z = 4.20
  75. EP241025a (GRB 241025A): EP on-board trigger and autonomous follow-up observation
  76. GRB 241025A: SVOM/GRM observation
  77. GRB 241025A: TRT optical afterglow observation
  78. Fermi GRB 241024B: Global MASTER-Net observations report
  79. GRB 241025A: Fermi GBM Final Real-time Localization
  80. GRB 241001A: ATCA radio observations
  81. GRB 241024B: Fermi GBM Final Localization
  82. EP241021a: No Detection in Fermi-GBM Observation
  83. GRB 241024A: Fermi GBM Final Localisation
  84. EP241021a: VLT/FORS2 redshift z = 0.75
  85. Fermi trigger No 751449953: Global MASTER-Net observations report
  86. EP241021a: EP-FXT follow-up observation update
  87. IPN triangulation of GRB 241021A (long)
  88. EP241021a: 1.3m DFOT Optical observations
  89. GRB 241018A: SVOM/C-GFT optical observations
  90. EP EP241021a: Global MASTER-Net observations report
  91. GRB241017A: 1.3m DFOT optical upper limit
  92. GRB 241018A: 1.3m DFOT Optical upper limit
  93. IceCube-Cascade 241019A: Upper limits from a search for additional neutrino events in IceCube
  94. Konus-Wind detection of GRB 241018A
  95. GRB 241018A: SVOM/GRM observation
  96. GRB 241018A/sb24101802: Mephisto optical upper limit
  97. GRB 241017A/sb24101702: Mephisto optical upper limit
  98. GRB 241018A: REM optical/NIR upper limits
  99. GRB 241017A: SVOM/VT follow-up and optical upper limit
  100. GRB 241016B: Fermi GBM Observations

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