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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"

38663 results found.

  1. The EP-WXT trigger 01709258455 is likely a flaring star
  2. EP-WXT 01709258455: NOT optical upper limits
  3. EP260214b: Mondy optical observations
  4. EP260214b: 1.3m DFOT optical upper limit
  5. EP260210a: Mondy optical upper limits
  6. Konus-Wind detection of GRB 260212A
  7. GRB 260208A: AbAO and Terskol optical upper limits
  8. GRB 260208A: continued Mondy optical observations
  9. IPN triangulation of GRB 260212A
  10. IceCube-260217A - IceCube observation of a high-energy neutrino candidate track-like event
  11. GRB 260213A: GECAM-B observation of a short burst
  12. GRB 260216A: Fermi Gamma-ray Burst Monitor trigger 792969362/260216886 is not a GRB
  13. GRB 260216A: Fermi GBM Final Real-time Localization
  14. EP260214b: Liverpool Telescope optical observations
  15. EP260214b: Optical upper limit with Kinder observations
  16. EP260214a: Optical upper limits with Kinder observations
  17. EP260214b: EP-FXT follow-up observation
  18. EP260214a / GRB 260214A: Fermi-GBM Sub-Threshold Detection
  19. EP260214b: DDOTI Optical Detection
  20. EP260214b: GROWTH-India Telescope optical upper limit
  21. EP260214a: VLT near-infrared observation
  22. EP260214b: SVOM/VT optical observation
  23. EP260214a: NOT optical upper limits
  24. EP260214a: COLIBRÍ optical upper limits
  25. EP260214b: OHP/T120 optical observations
  26. EP260214a: refined analysis of the EP-FXT observation
  27. EP260214b: LCO optical counterpart detection
  28. EP260214b: VLT/X-shooter spectroscopic redshift z = 1.208
  29. GRB 260211A: SVOM/VT optical counterpart
  30. EP260214b: COLIBRÍ optical observations
  31. EP260214a: SVOM/VT optical upper limits
  32. EP260214b: NOT optical counterpart detection
  33. EP260214b: Einstein Probe detection of a fast X-ray transient
  34. EP260214a: Einstein Probe detection of an X-ray transient
  35. GRB 260212A: AstroSat CZTI detection
  36. GRB 260212A: Fermi GBM Observation
  37. EP260213a: Liverpool Telescope optical upper limits
  38. EP260213a: COLIBRÍ optical upper limits
  39. GRB 260212A: GECAM-B observation
  40. EP260213a: Optical upper limits with Kinder observations
  41. EP260213a: SVOM/VT optical upper limit
  42. EP260213a: Mondy R-band optical upper limit
  43. EP260213a: NUTTelA-TAO Early Optical Limits
  44. EP260213a: SVOM/C-GFT upper limit
  45. EP260213a: refined analysis of the EP-FXT observation
  46. EP260213a: Einstein Probe detection of a fast X-ray transient
  47. EP/WXT 01709258378: NOT optical upper limits
  48. GRB 260212A: SVOM/GRM observation of a long burst
  49. GRB 260213B: Fermi GBM Final Localization
  50. GRB 260213B: BALROG localization (Fermi Trigger 792697214 / GRB 260213736)
  51. GRB 260211A - SVOM/ECLAIRs refined analysis
  52. GRB 260204A: SVOM/ECLAIRs refined analysis
  53. GRB 260213A: Fermi GBM Final Localization
  54. GRB 260211A: EP-FXT follow-up observation
  55. GRB 260211A: SVOM/VT optical observation
  56. GRB 260212A: Glowbug gamma-ray detection
  57. GRB 260211A: GOTO optical upper limit
  58. GRB 260212A: Fermi GBM Final Real-time Localization
  59. GRB 260211A: LAST optical upper limit
  60. GRB 260210A: SVOM/GRM observation
  61. Fermi GBM Sub-Threshold Detection of GRB 260211A
  62. Konus-Wind detection of GRB 260207B
  63. GRB 260128B: SVOM/ECLAIRs refined analysis
  64. GRID detection of GRB 260207B
  65. GRB 260211A: LCO optical upper limits
  66. GRB260131A/B: 3.6m DOT Optical Observations
  67. GRB 260211A: SVOM/COLIBRÍ (FM-GFT) optical upper limits
  68. GRB 260211A: SVOM detection of a burst
  69. Swift Operations Update + Community Forum (Friday, February 13 @ 10:00 AM EST)
  70. Konus-Wind detection of GRB 260209B
  71. GRB 260208A: Swift UVOT detection
  72. Konus-Wind detection of GRB 260127B
  73. EP260209a: COLIBRÍ optical upper limit
  74. EP260209a: LCO optical upper limits
  75. EP260210a: refined analysis of the EP-FXT observation
  76. GRB 260208A: LCO detection of the optical counterpart
  77. EP260209a: Einstein Probe detection of a fast X-ray transient
  78. EP260210a: Optical upper limits with Kinder observations
  79. IPN triangulation of GRB 260207B (short/hard with EE)
  80. GRB 260210C: Fermi GBM Final Real-time Localization
  81. GRB 260210A: Glowbug gamma-ray detection
  82. GRB 260210B: Fermi GBM Final Real-time Localization
  83. EP260210a: SVOM/VT optical upper limit
  84. GRB 260210A: AstroSat CZTI detection
  85. GRB 260208C: AstroSat CZTI detection
  86. EP260210a: COLIBRÍ optical upper limit
  87. EP260210a: SVOM/C-GFT upper limit
  88. GRB 260208B: refined analysis of the EP-FXT observation
  89. EP260210a: Einstein Probe detection of an X-ray transient
  90. GRB 260207B: AstroSat CZTI detection
  91. GRB 260208C: SVOM/GRM observation
  92. GRB 260204A: Swift-XRT afterglow detection
  93. GRB 260208B: AstroSat CZTI detection of a bright long burst
  94. GRB260208A: Liverpool Telescope optical follow-up observations
  95. GRB 260208A: Glowbug gamma-ray detection
  96. GRB 260208A: NuSTAR detection of prompt emission
  97. GRB 260208A: Fermi GBM Observation
  98. GRB 260208B: Swift-XRT observations
  99. GRB 260131A/B: continued Mondy optical observations
  100. GRB 260204A: Swift/UVOT Upper Limits

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