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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"

37684 results found.

  1. GRB 240521B: Swift/BAT-GUANO arcminute localization of a long burst
  2. Fermi trigger No 737996942: Global MASTER-Net observations report
  3. GRB 240521A: GECAM-B detection of a long burst
  4. GRB 240516B: AstroSat CZTI detection
  5. LIGO/Virgo/KAGRA S240515m: Upper limits from Swift/BAT-GUANO
  6. LIGO/Virgo/KAGRA S240514x: Upper limits from Swift/BAT-GUANO
  7. LIGO/Virgo/KAGRA S240513ei: Upper limits from Swift/BAT-GUANO
  8. GRB 240514B: VZLUSAT-2 detection
  9. GRB 240504A: VZLUSAT-2 detection
  10. GRB 240502A: VZLUSAT-2 detection
  11. GRB 240519A: GRBAlpha detection
  12. GRB 240516A: Swift/UVOT Upper Limits
  13. GRB 240519A: AstroSat CZTI detection
  14. Fermi trigger No 737788024: Global MASTER-Net observations report
  15. GRB 240519A: BALROG localization (Fermi Trigger 737788024 / GRB 240519213)
  16. GRB 240516A: Swift-BAT refined analysis
  17. Fermi GRB 240517A: Global MASTER-Net observations report
  18. GRB 240516A ATCA radio observations
  19. IPN triangulation of GRB 240514B (short)
  20. GRB 240513A: Swift ToO observations
  21. GRB 240517A: Fermi GBM Final Real-time Localization
  22. Konus-Wind detection of GRB 240513A
  23. GRB 240516A: AstroSat CZTI detection
  24. GRB 240516A: Swift-XRT refined Analysis
  25. GRB 240514E: A possible candidate BD-21 1074
  26. Fermi trigger No 737559855: Global MASTER-Net observations report
  27. GRB 240516A: Fermi GBM Observation
  28. GRB 240511A: Observations from GTC/OSIRIS+
  29. GRB 240502C: Zeiss-1000 at Koshka observations of GOTO24bao optical counterpart candidate
  30. GRB 240516A: GOTO optical upper limit
  31. LIGO/Virgo/KAGRA S240422ed: GRID non-detection and upper limits
  32. Fermi trigger No 737523389: Global MASTER-Net observations report
  33. GRB 240516A: Swift detection of a burst
  34. GRB 240514B: AT2024ixa/GOTO24bph is not consistent with the Fermi localisation
  35. Fermi trigger No 737476171: Global MASTER-Net observations report
  36. GRB 240511A: radio detection of afterglow candidate
  37. GRB 240514B: GOTO candidate optical counterpart
  38. Fermi Gamma-ray Burst Monitor list of triggers that are not a GRB
  39. GRB 240514E: MAXI/GSC detection of a probable afterglow
  40. GRB 240514B: GRBAlpha detection
  41. GRB 240514B: Fermi GBM Detection
  42. GRB 240513A: Fermi GBM observation
  43. GRB 240513A: Swift-XRT observations
  44. GRB 240514D: AstroSat CZTI detection
  45. GRB 240514C: Fermi GBM Final Real-time Localization
  46. Fermi GRB 240514B: Global MASTER-Net observations report
  47. Fermi Gamma-ray Burst Monitor triggers 737345659/240514093 and GRB240514A are not GRBs
  48. GRB 240514B: Fermi GBM Final Real-time Localization
  49. LIGO/Virgo/KAGRA S240507p: Upper limits from Swift/BAT-GUANO
  50. LIGO/Virgo/KAGRA S240505av: Upper limits from Swift/BAT-GUANO
  51. LIGO/Virgo/KAGRA S240505av: Upper limits from Swift/BAT-GUANO
  52. GRB 240514A: Fermi GBM Final Real-time Localization
  53. GRB 240513A: Tiled Swift observations
  54. GRB 240513A: Fermi-LAT detection
  55. GRB 240511A: Fermi GBM Observation
  56. GRB 240511A: Swift-BAT refined analysis
  57. Fermi GRB 240513B: Global MASTER-Net observations report
  58. Fermi trigger No 737277727: Global MASTER-Net observations report
  59. GRB 240513B: Fermi GBM Final Real-time Localization
  60. GRB 240513A: AstroSat CZTI detection
  61. Fermi trigger No 737258655: Global MASTER-Net observations report
  62. GRB 240511A: J-band observations with WINTER
  63. Fermi trigger No 737247400: Global MASTER-Net observations report
  64. Fermi trigger No 737244199: Global MASTER-Net observations report
  65. Fermi trigger No 737218721: Global MASTER-Net observations report
  66. Fermi trigger No 737196587: Global MASTER-Net observations report
  67. Fermi trigger No 737168073: Global MASTER-Net observations report
  68. GRB 240511A: Enhanced Swift-XRT position
  69. GRB 240511A : MITSuME Akeno optical upper limits
  70. GRB 240511A: Swift-XRT refined Analysis
  71. GRB 240511A: optical afterglow detection from the NOT
  72. Fermi Gamma-ray Burst Monitor trigger 737102480/240511279 is not a GRB
  73. Fermi Gamma-ray Burst Monitor trigger 737111207/240511380 is not a GRB
  74. Fermi GBM trigger 737105243/240511311 is not a GRB
  75. Fermi trigger No 737173236: Global MASTER-Net observations report
  76. Fermi GRB 240511A: Global MASTER-Net observations report
  77. Swift GRB 240511A: Global MASTER-Net observations report
  78. Fermi trigger No 737105243: Global MASTER-Net observations report
  79. Fermi Gamma-ray Burst Monitor trigger 737133200/240511634 is not a GRB
  80. Fermi trigger No 737152719: Global MASTER-Net observations report
  81. GRB 240511A: Prompt enhanced Swift-XRT position
  82. GRB 240511A: Swift detection of a burst
  83. GRB 240511A: Fermi GBM Final Real-time Localization
  84. Fermi trigger No 737102480: Global MASTER-Net observations report
  85. Fermi trigger No 737111207: Global MASTER-Net observations report
  86. Fermi Gamma-ray Burst Monitor trigger 737076431/240510977 is not a GRB
  87. Fermi trigger No 736967879: Global MASTER-Net observations report
  88. Fermi Gamma-ray Burst Monitor trigger 230925241/717313591 is not a GRB
  89. EP240506a: CrAO ZTSH optical upper limit
  90. GRB 240504A: Fermi GBM Observation
  91. Fermi Gamma-ray Burst Monitor trigger 736837160/240508208 is not a GRB
  92. Fermi trigger No 736733320: Global MASTER-Net observations report
  93. IPN triangulation of GRB 240504A
  94. GRB 240502A: 1.3m DFOT Optical upper limit
  95. GRB 240504A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  96. Fermi GBM triggers 736668287/240506253 and 736669277/240506265 are not GRBs
  97. Fermi trigger No 736564880: Global MASTER-Net observations report
  98. IceCube-240424A: GRANDMA Optical Upper Limit of Fermi J2151.3+0220
  99. GRB 240502C: Zeiss-1000 at Koshka observatory observations of GOTO optical counterpart candidates
  100. Fermi trigger No 736461232: Global MASTER-Net observations report

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