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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"

28196 results found.

  1. EP260302a: Einstein Probe detection of an X-ray transient
  2. GRB 251130B: TERI Gamma-ray detection
  3. GRB 260208A: TERI Gamma-ray detection
  4. GRB 260302A: Fermi GBM Final Real-time Localization
  5. GRB 260228A: CAHA 2.2m telescope optical upper limit
  6. EP260227a: Mephisto optical detection
  7. GRID detection of GRB 260225D
  8. EP260227A: 3.6m DOT optical afterglow detection
  9. GRB 260228A: SVOM detection of a burst
  10. GRB 260226A: Asiago r-band upper limit
  11. EP260227a: Liverpool Telescope observations
  12. GRID detection of GRB 260223A
  13. EP260227a: Einstein Probe detection of an X-ray transient and refined analysis
  14. EP/WXT trigger 01709258681 (EP260227a?): LCO candidate afterglow
  15. IceCube cascade alert 142200_1517143 retraction
  16. GRB 260226A: Insight-HXMT/HE detection of the very bright burst
  17. Konus-Wind detection of GRB 260226A
  18. GRB 260223A: 7DT detection and Medium-band SED of Afterglow
  19. GRB 260226A: CALET Gamma-Ray Burst Monitor detection
  20. GRB 260225D: Glowbug gamma-ray detection of a likely short burst
  21. GRB 260226A: Glowbug gamma-ray detection
  22. GRB 260226A: NuSTAR detection of bright prompt emission
  23. GRB 260226A: AstroSat CZTI detection of bright long burst
  24. EP260214a: VLA 6 GHz detection
  25. GRB 260226A: Fermi-LAT detection of a bright burst
  26. GRB 260226A: Fermi GBM Final Real-time Localization
  27. GRB 260225A: SVOM/COLIBRÍ (FM-GFT) Detection of an Optical Counterpart Candidate
  28. GRB 260225C: Fermi GBM Final Real-time Localization
  29. GRB 260225A: SVOM/VT optical upper limits
  30. GRB 260225B: Fermi GBM Final Real-time Localization
  31. EP260126a: VLA 6 GHz detection
  32. EP260223a: Liverpool Telescope upper limits
  33. GRB 260225A: SVOM detection of a burst
  34. EP260224a: Einstein Probe detection of an X-ray transient
  35. EP260223a: Xinglong optical upper limit
  36. GRB 260223A: Glowbug gamma-ray detection
  37. EP260213a: Mephisto optical upper limits
  38. EP260223a: EP-FXT follow-up observation
  39. sb26021801: SVOM/VT optical upper limits
  40. GRB 260223A: COLIBRÍ optical afterglow decay confirmation
  41. EP260223a: Einstein Probe detection of an X-ray transient
  42. EP260221a: Optical upper limit with Kinder observations
  43. GRB 260223A: Fermi GBM Final Real-time Localization
  44. EP260221a: Liverpool Telescope detection of COLIBRÍ counterpart candidate
  45. EP260221a: COLIBRÍ optical counterpart candidate
  46. EP260221a: Gemini South z-band upper limit
  47. GRB 260222A: Fermi GBM Final Real-time Localization
  48. GRB 260221B: Fermi GBM Final Real-time Localization
  49. EP-WXT01709258519: Xinglong optical upper limit
  50. EP260221a: Xinglong optical upper limit
  51. GRB 260221A: Fermi GBM Final Real-time Localization
  52. EP260221a: Einstein Probe detection of an X-ray transient
  53. GRB 260219A: AstroSat CZTI detection
  54. GRB 260219A: Fermi GBM Final Real-time Localization
  55. GRB 260217A: Fermi GBM Final Localization
  56. GRB 260214B/EP260214b: SVOM/ECLAIRs detection through targeted search
  57. sb26021801: SVOM detection of a long faint X-ray transient
  58. EP260214b: 1.3m DFOT optical upper limit
  59. Konus-Wind detection of GRB 260212A
  60. IPN triangulation of GRB 260212A
  61. IceCube-260217A - IceCube observation of a high-energy neutrino candidate track-like event
  62. GRB 260216A: Fermi GBM Final Real-time Localization
  63. GRB 260206A: probable hard X-ray burst from 4U 0513-40
  64. EP260214b: Optical upper limit with Kinder observations
  65. EP260214a: Optical upper limits with Kinder observations
  66. EP260214b: EP-FXT follow-up observation
  67. EP260214a / GRB 260214A: Fermi-GBM Sub-Threshold Detection
  68. EP260214b: DDOTI Optical Detection
  69. EP260214b: LCO optical counterpart detection
  70. EP260214b: VLT/X-shooter spectroscopic redshift z = 1.208
  71. EP260214b: NOT optical counterpart detection
  72. EP260214b: Einstein Probe detection of a fast X-ray transient
  73. EP260214a: Einstein Probe detection of an X-ray transient
  74. GRB 260212A: AstroSat CZTI detection
  75. EP260213a: Liverpool Telescope optical upper limits
  76. EP260213a: Optical upper limits with Kinder observations
  77. EP260213a: Einstein Probe detection of a fast X-ray transient
  78. GRB 260213B: Fermi GBM Final Localization
  79. GRB 260204A: SVOM/ECLAIRs refined analysis
  80. GRB 260213A: Fermi GBM Final Localization
  81. GRB 260212A: Glowbug gamma-ray detection
  82. GRB 260212A: Fermi GBM Final Real-time Localization
  83. Fermi GBM Sub-Threshold Detection of GRB 260211A
  84. Konus-Wind detection of GRB 260207B
  85. GRID detection of GRB 260207B
  86. GRB260131A/B: 3.6m DOT Optical Observations
  87. GRB 260211A: SVOM detection of a burst
  88. Swift Operations Update + Community Forum (Friday, February 13 @ 10:00 AM EST)
  89. Konus-Wind detection of GRB 260209B
  90. GRB 260208A: Swift UVOT detection
  91. Konus-Wind detection of GRB 260127B
  92. GRB 260208A: LCO detection of the optical counterpart
  93. EP260209a: Einstein Probe detection of a fast X-ray transient
  94. IPN triangulation of GRB 260207B (short/hard with EE)
  95. GRB 260210C: Fermi GBM Final Real-time Localization
  96. GRB 260210A: Glowbug gamma-ray detection
  97. GRB 260210B: Fermi GBM Final Real-time Localization
  98. GRB 260210A: AstroSat CZTI detection
  99. GRB 260208C: AstroSat CZTI detection
  100. GRB 260208B: refined analysis of the EP-FXT observation

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