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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"

38134 results found.

  1. GRB 260223A: Fermi GBM Observation
  2. GRB 260225A: SVOM/VT optical upper limits
  3. GRB 260225B: Fermi GBM Final Real-time Localization
  4. GRB 260225A: SVOM/COLIBRÍ (FM-GFT) optical upper limits
  5. GRB 260225A: SVOM detection of a burst
  6. GRB 260223A: Glowbug gamma-ray detection
  7. GRB 260223A: COLIBRÍ optical afterglow decay confirmation
  8. GRB 260223A: SVOM/VT optical observation
  9. GRB 260223A: SVOM/GRM observation
  10. GRB 260223A: COLIBRÍ further optical observations and a brightening
  11. GRB 260223A: COLIBRÍ optical observations
  12. GRB 260223A: DDOTI Optical Candidate
  13. GRB 260223A: BALROG localization (Fermi Trigger 793512674 / GRB 260223174)
  14. Fermi GRB 260223A: Global MASTER-Net observations report
  15. GRB 260223A: Fermi GBM Final Real-time Localization
  16. GRB 260222A: Fermi GBM Final Real-time Localization
  17. EP260221a: Global MASTER-Net observations report
  18. Fermi GRB 260221B: Global MASTER-Net observations report
  19. GRB 260221B: Fermi GBM Final Real-time Localization
  20. Fermi GRB 260221A: Global MASTER-Net observations report
  21. GRB 260221A: Fermi GBM Final Real-time Localization
  22. GRB 260219A: AstroSat CZTI detection
  23. GRB 260219A: GECAM-B observation of a long burst
  24. Fermi GRB 260219A: Global MASTER-Net observations report
  25. GRB 260219A: Fermi GBM Final Real-time Localization
  26. IceCube Alert 260217A: Global MASTER-Net observations report
  27. GRB 260217A: Fermi GBM Final Localization
  28. GRB 260214B/EP260214b: SVOM/ECLAIRs detection through targeted search
  29. EP260214b: Mondy optical observations
  30. EP260210a: Mondy optical upper limits
  31. Konus-Wind detection of GRB 260212A
  32. GRB 260208A: AbAO and Terskol optical upper limits
  33. GRB 260208A: continued Mondy optical observations
  34. IPN triangulation of GRB 260212A
  35. GRB 260213A: GECAM-B observation of a short burst
  36. GRB 260216A: Fermi Gamma-ray Burst Monitor trigger 792969362/260216886 is not a GRB
  37. GRB 260216A: Fermi GBM Final Real-time Localization
  38. GRB 260206A: probable hard X-ray burst from 4U 0513-40
  39. EP260214a: Optical upper limits with Kinder observations
  40. EP260214a / GRB 260214A: Fermi-GBM Sub-Threshold Detection
  41. EP260214a: refined analysis of the EP-FXT observation
  42. EP260214b: LCO optical counterpart detection
  43. EP260214b: VLT/X-shooter spectroscopic redshift z = 1.208
  44. GRB 260211A: SVOM/VT optical counterpart
  45. EP260214a: Global MASTER-Net observations report
  46. GRB 260212A: AstroSat CZTI detection
  47. GRB 260212A: Fermi GBM Observation
  48. EP260213a: Global MASTER-Net observations report
  49. GRB 260212A: GECAM-B observation
  50. EP260213a: Mondy R-band optical upper limit
  51. GRB 260212A: SVOM/GRM observation of a long burst
  52. GRB 260213B: Fermi GBM Final Localization
  53. GRB 260213B: BALROG localization (Fermi Trigger 792697214 / GRB 260213736)
  54. GRB 260211A - SVOM/ECLAIRs refined analysis
  55. GRB 260204A: SVOM/ECLAIRs refined analysis
  56. GRB 260213A: Fermi GBM Final Localization
  57. GRB 260211A: EP-FXT follow-up observation
  58. GRB 260211A: SVOM/VT optical observation
  59. GRB 260212A: Glowbug gamma-ray detection
  60. GRB 260211A: GOTO optical upper limit
  61. Fermi GRB 260212A: Global MASTER-Net observations report
  62. GRB 260212A: Fermi GBM Final Real-time Localization
  63. GRB 260211A: LAST optical upper limit
  64. GRB 260210A: SVOM/GRM observation
  65. Fermi GBM Sub-Threshold Detection of GRB 260211A
  66. Konus-Wind detection of GRB 260207B
  67. GRB 260128B: SVOM/ECLAIRs refined analysis
  68. GRID detection of GRB 260207B
  69. GRB 260211A: LCO optical upper limits
  70. GRB260131A/B: 3.6m DOT Optical Observations
  71. GRB 260211A: SVOM/COLIBRÍ (FM-GFT) optical upper limits
  72. Fermi trigger No 792537871: Global MASTER-Net observations report
  73. GRB 260211A: SVOM detection of a burst
  74. Konus-Wind detection of GRB 260209B
  75. GRB 260208A: Swift UVOT detection
  76. Konus-Wind detection of GRB 260127B
  77. Fermi GRB 260210C: Global MASTER-Net observations report
  78. EP260210a: Global MASTER-Net observations report
  79. EP260209a: Global MASTER-Net observations report
  80. GRB 260208A: LCO detection of the optical counterpart
  81. IPN triangulation of GRB 260207B (short/hard with EE)
  82. GRB 260210C: Fermi GBM Final Real-time Localization
  83. GRB 260210A: Glowbug gamma-ray detection
  84. GRB 260210B: Fermi GBM Final Real-time Localization
  85. GRB 260210A: AstroSat CZTI detection
  86. GRB 260208C: AstroSat CZTI detection
  87. GRB 260208B: refined analysis of the EP-FXT observation
  88. GRB 260207B: AstroSat CZTI detection
  89. GRB 260208C: SVOM/GRM observation
  90. GRB 260204A: Swift-XRT afterglow detection
  91. GRB 260208B: AstroSat CZTI detection of a bright long burst
  92. GRB 260208A: Glowbug gamma-ray detection
  93. GRB 260208A: NuSTAR detection of prompt emission
  94. GRB 260208A: Fermi GBM Observation
  95. Fermi GRB 260209A: Global MASTER-Net observations report
  96. GRB 260208B: Swift-XRT observations
  97. GRB 260131A/B: continued Mondy optical observations
  98. GRB 260204A: Swift/UVOT Upper Limits
  99. GRB 260208B: COLIBRÍ optical observations
  100. GRB 260208A: Mondy optical observations (duplicate submission)

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