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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"

1022 results found.

  1. GRB 260608A: SVOM/ECLAIRs refined analysis
  2. GRB 260604C: SVOM/COLIBRÍ (FM-GFT) colour evolution and confirmation of the late rebrightening
  3. GRB 260604C: SVOM/C-GFT upper limit
  4. GRB 260608A: SVOM detection of a burst
  5. GRB 260604A: SVOM/GRM detection
  6. GRB 260604B: SVOM/GRM detection
  7. GRB260603A: SVOM/ECLAIRs refined analysis
  8. GRB 260604C: LCO optical upper limit
  9. GRB 260604C: SVOM/COLIBRÍ (FM-GFT) optical observations
  10. GRB 260515A: SVOM/VT optical detection at about 18 days post trigger
  11. GRB 260603A: SVOM/VT optical observations
  12. GRB 260603A: SVOM/COLIBRÍ (FM-GFT) photometric redshift z = 3.57
  13. EP260602a: SVOM/VT optical magnitudes correction
  14. GRB 260601A: SVOM/GRM observation of a short burst
  15. GRB 260603A: SVOM detection of a burst
  16. EP260602a: SVOM/VT optical candidate
  17. GRB 260601B/EP260601a: SVOM/VT optical observations
  18. GRB 260530C: SVOM/ECLAIRs detection of a burst through on-ground search
  19. GRB 260518B: SVOM/ECLAIRs detection of a soft burst possibly associated with EP 260518a and AT 2026ndp
  20. GRB 260530B: SVOM/GRM detection of a possible bright short GRB
  21. EP260526a: SVOM/VT optical upper limits
  22. EP260527a: SVOM/VT optical observation
  23. GRB 260524A: SVOM/ECLAIRs detection of a burst through on-ground search
  24. GRB 260519C: SVOM/GRM observation
  25. GRB 260520B: SVOM/GRM observation
  26. GRB 260509A: SVOM/ECLAIRs refined analysis
  27. GRB 260516D: SVOM/ECLAIRs refined analysis
  28. GRB 260515A: SVOM/ECLAIRs refined analysis
  29. GRB 260516D: LCO optical observations
  30. GRB 260516D: SVOM/COLIBRÍ (FM-GFT) optical observations
  31. GRB 260516D: SVOM/VT optical bright candidate
  32. GRB 260516D: SVOM possible detection of a burst
  33. GRB 260515A: SVOM/COLIBRÍ (FM-GFT) optical observations
  34. EP260514a: SVOM/VT optical candidate
  35. GRB 260515A: SVOM/VT optical observations
  36. GRB 260515A: LCO optical observations
  37. GRB 260515A: SVOM/VT optical candidate from VHF data
  38. GRB 260515A: SVOM detection of a burst
  39. GRB 260509A: SVOM/VT optical observations
  40. GRB 260511A: SVOM/VT optical observations
  41. GRB 260511B: LCO optical observations
  42. GRB 260510C: SVOM/COLIBRÍ (FM-GFT) further optical observations
  43. GRB 260511B: SVOM/VT optical observations
  44. GRB 260511B: SVOM/COLIBRÍ (FM-GFT) optical observations
  45. GRB 260511B: SVOM/VT optical observation with VHF data
  46. GRB 260510B: SVOM/ECLAIRs refined analysis
  47. GRB 260511B SVOM/C-GFT optical counterpart detection
  48. GRB 260511B: SVOM detection of a burst
  49. GRB 260510C: SVOM/VT optical counterpart confirmation
  50. GRB 260511A: SVOM/VT optical observation with VHF data
  51. GRB 260511A: LCO optical afterglow detection
  52. GRB 260511A: SVOM/COLIBRÍ (FM-GFT) optical counterpart
  53. GRB 260511A: SVOM detection of a bright burst
  54. GRB 260510C: SVOM/COLIBRÍ (FM-GFT) optical counterpart candidate
  55. GRB 260510B: SVOM/VT optical upper limits
  56. GRB 260510C: SVOM/VT optical upper limits
  57. GRB 260510B: LCO optical upper limits
  58. GRB 260510B: SVOM detection of a burst
  59. GRB 260509A: SVOM/COLIBRÍ (FM-GFT) observations
  60. GRB 260509A: SVOM/VT optical candidate with VHF data
  61. GRB 260509A: LCO optical counterpart detection
  62. EP260507a: SVOM/VT optical observations
  63. GRB 260504B: SVOM/ECLAIRs refined analysis
  64. GRB 260504B: SVOM/VT optical upper limits
  65. GRB 260504C: SVOM/GRM observation of short GRB
  66. GRB 260504B: SVOM/GRM spectral analysis
  67. GRB 260504B: SVOM/MXT refined analysis and potential detection
  68. GRB 260502A: SVOM/GRM observation of a short GRB
  69. GRB 260503A: SVOM/GRM observation of a GRB
  70. GRB 260504B: LCO z-band upper limit
  71. GRB 260504B: SVOM detection of a short burst
  72. SVOM/GRM observation of a bright burst from SGR 1E1841-045
  73. GRB 260429A: SVOM/GRM observation of a short burst
  74. GRB 260428A: SVOM/GRM observation of a possible short burst with extended emission
  75. GRB 260424B: SVOM/GRM detection of a short burst
  76. GRB 260421B: SVOM/ECLAIRs refined analysis
  77. GRB 260421B: SVOM/GRM observation
  78. GRB 260412A: SVOM/ECLAIRs refined analysis
  79. GRB 260421B: SVOM/VT optical observations
  80. GRB 260421B: LCO optical afterglow confirmation
  81. GRB 260421B: SVOM/COLIBRÍ (FM-GFT) optical detection of a candidate counterpart
  82. GRB 260421B: SVOM detection of a long burst
  83. GRB 260417A: SVOM/GRM observation
  84. EP260416a: SVOM/VT optical observation
  85. GOTO26djh/AT2026jpw: SVOM/VT optical observation
  86. EP260321a: SVOM/VT optical observations and color changes around peak
  87. GRB 260412A: SVOM detection of a long burst
  88. GRB 260411A: SVOM/GRM observation
  89. GRB 260407B: SVOM/GRM detection of a possible magnetar X-ray burst
  90. GRB 260411B: SVOM/GRM observation of a long burst
  91. GRB 260410B: SVOM/GRM detection of a short faint burst
  92. EP260409a: SVOM/VT optical upper limits
  93. GRB 260402A: SVOM/ECLAIRs refined analysis
  94. EP260405a: SVOM/VT optical upper limits
  95. GRB 260330B: SVOM/VT further optical observation
  96. GRB 260330B: SVOM/ECLAIRs refined analysis
  97. GRB 260330B: SVOM/VT optical candidate
  98. GRB 260330B: EP-FXT follow-up and identification of candidate afterglow
  99. GRB 260402A / EP260402a: SVOM/VT optical upper limits
  100. EP260402a/GRB 260402A: SVOM/C-GFT upper limit

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