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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"

37768 results found.

  1. Fermi GRB 240517A: Global MASTER-Net observations report
  2. GRB 240516A ATCA radio observations
  3. IPN triangulation of GRB 240514B (short)
  4. GRB 240513A: Swift ToO observations
  5. GRB 240517A: Fermi GBM Final Real-time Localization
  6. Konus-Wind detection of GRB 240513A
  7. GRB 240516A: AstroSat CZTI detection
  8. GRB 240516A: Swift-XRT refined Analysis
  9. GRB 240514E: A possible candidate BD-21 1074
  10. Fermi trigger No 737559855: Global MASTER-Net observations report
  11. GRB 240516A: Fermi GBM Observation
  12. GRB 240511A: Observations from GTC/OSIRIS+
  13. GRB 240502C: Zeiss-1000 at Koshka observations of GOTO24bao optical counterpart candidate
  14. GRB 240516A: GOTO optical upper limit
  15. LIGO/Virgo/KAGRA S240422ed: GRID non-detection and upper limits
  16. Fermi trigger No 737523389: Global MASTER-Net observations report
  17. GRB 240516A: Swift detection of a burst
  18. GRB 240514B: AT2024ixa/GOTO24bph is not consistent with the Fermi localisation
  19. Fermi trigger No 737476171: Global MASTER-Net observations report
  20. GRB 240511A: radio detection of afterglow candidate
  21. GRB 240514B: GOTO candidate optical counterpart
  22. Fermi Gamma-ray Burst Monitor list of triggers that are not a GRB
  23. GRB 240514E: MAXI/GSC detection of a probable afterglow
  24. GRB 240514B: GRBAlpha detection
  25. GRB 240514B: Fermi GBM Detection
  26. GRB 240513A: Fermi GBM observation
  27. GRB 240513A: Swift-XRT observations
  28. GRB 240514D: AstroSat CZTI detection
  29. GRB 240514C: Fermi GBM Final Real-time Localization
  30. Fermi GRB 240514B: Global MASTER-Net observations report
  31. Fermi Gamma-ray Burst Monitor triggers 737345659/240514093 and GRB240514A are not GRBs
  32. GRB 240514B: Fermi GBM Final Real-time Localization
  33. LIGO/Virgo/KAGRA S240507p: Upper limits from Swift/BAT-GUANO
  34. LIGO/Virgo/KAGRA S240505av: Upper limits from Swift/BAT-GUANO
  35. LIGO/Virgo/KAGRA S240505av: Upper limits from Swift/BAT-GUANO
  36. GRB 240514A: Fermi GBM Final Real-time Localization
  37. GRB 240513A: Tiled Swift observations
  38. GRB 240513A: Fermi-LAT detection
  39. GRB 240511A: Fermi GBM Observation
  40. GRB 240511A: Swift-BAT refined analysis
  41. Fermi GRB 240513B: Global MASTER-Net observations report
  42. Fermi trigger No 737277727: Global MASTER-Net observations report
  43. GRB 240513B: Fermi GBM Final Real-time Localization
  44. GRB 240513A: AstroSat CZTI detection
  45. Fermi trigger No 737258655: Global MASTER-Net observations report
  46. GRB 240511A: J-band observations with WINTER
  47. Fermi trigger No 737247400: Global MASTER-Net observations report
  48. Fermi trigger No 737244199: Global MASTER-Net observations report
  49. Fermi trigger No 737218721: Global MASTER-Net observations report
  50. Fermi trigger No 737196587: Global MASTER-Net observations report
  51. Fermi trigger No 737168073: Global MASTER-Net observations report
  52. GRB 240511A: Enhanced Swift-XRT position
  53. GRB 240511A : MITSuME Akeno optical upper limits
  54. GRB 240511A: Swift-XRT refined Analysis
  55. GRB 240511A: optical afterglow detection from the NOT
  56. Fermi Gamma-ray Burst Monitor trigger 737102480/240511279 is not a GRB
  57. Fermi Gamma-ray Burst Monitor trigger 737111207/240511380 is not a GRB
  58. Fermi GBM trigger 737105243/240511311 is not a GRB
  59. Fermi trigger No 737173236: Global MASTER-Net observations report
  60. Fermi GRB 240511A: Global MASTER-Net observations report
  61. Swift GRB 240511A: Global MASTER-Net observations report
  62. Fermi trigger No 737105243: Global MASTER-Net observations report
  63. Fermi Gamma-ray Burst Monitor trigger 737133200/240511634 is not a GRB
  64. Fermi trigger No 737152719: Global MASTER-Net observations report
  65. GRB 240511A: Prompt enhanced Swift-XRT position
  66. GRB 240511A: Swift detection of a burst
  67. GRB 240511A: Fermi GBM Final Real-time Localization
  68. Fermi trigger No 737102480: Global MASTER-Net observations report
  69. Fermi trigger No 737111207: Global MASTER-Net observations report
  70. Fermi Gamma-ray Burst Monitor trigger 737076431/240510977 is not a GRB
  71. Fermi trigger No 736967879: Global MASTER-Net observations report
  72. Fermi Gamma-ray Burst Monitor trigger 230925241/717313591 is not a GRB
  73. EP240506a: CrAO ZTSH optical upper limit
  74. GRB 240504A: Fermi GBM Observation
  75. Fermi Gamma-ray Burst Monitor trigger 736837160/240508208 is not a GRB
  76. Fermi trigger No 736733320: Global MASTER-Net observations report
  77. IPN triangulation of GRB 240504A
  78. GRB 240502A: 1.3m DFOT Optical upper limit
  79. GRB 240504A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  80. Fermi GBM triggers 736668287/240506253 and 736669277/240506265 are not GRBs
  81. Fermi trigger No 736564880: Global MASTER-Net observations report
  82. IceCube-240424A: GRANDMA Optical Upper Limit of Fermi J2151.3+0220
  83. GRB 240502C: Zeiss-1000 at Koshka observatory observations of GOTO optical counterpart candidates
  84. Fermi trigger No 736461232: Global MASTER-Net observations report
  85. IPN triangulation of GRB 240501B and GRB 240501A - possible episodes of ultra long GRB
  86. Fermi GRB 240504A: Global MASTER-Net observations report
  87. Fermi trigger No 736472503: Global MASTER-Net observations report
  88. GRB 240503A: AstroSat CZTI detection
  89. GRB 240504A: BALROG localization (Fermi Trigger 736492377 / GRB 240504217)
  90. GRB 240504A: Fermi GBM Final Real-time Localization
  91. Fermi trigger No 736387941: Global MASTER-Net observations report
  92. LXT 240402A / GRB 240402B: VLT X-shooter redshift of host
  93. GRB 240502A: GOTO optical upper limit
  94. Fermi trigger No 736379109: Global MASTER-Net observations report
  95. GRB 240502A: Fermi GBM Observation
  96. GRB 240415A 1.3m DFOT Optical upper limit
  97. GRB 240502C: GOTO possible optical counterpart candidates
  98. Fermi GRB 240502B: Global MASTER-Net observations report
  99. GRB 240502C: Fermi GBM Final Localization
  100. Fermi GRB 240502A: Global MASTER-Net observations report

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