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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"

45735 results found.

  1. GRB 260217A: Fermi GBM Final Localization
  2. GRB 260214B/EP260214b: SVOM/ECLAIRs detection through targeted search
  3. sb26021801: SVOM detection of a long faint X-ray transient
  4. The EP-WXT trigger 01709258455 is likely a flaring star
  5. EP-WXT 01709258455: NOT optical upper limits
  6. EP260214b: Mondy optical observations
  7. EP260214b: 1.3m DFOT optical upper limit
  8. EP260210a: Mondy optical upper limits
  9. Konus-Wind detection of GRB 260212A
  10. GRB 260208A: AbAO and Terskol optical upper limits
  11. GRB 260208A: continued Mondy optical observations
  12. IPN triangulation of GRB 260212A
  13. IceCube-260217A - IceCube observation of a high-energy neutrino candidate track-like event
  14. GRB 260213A: GECAM-B observation of a short burst
  15. GRB 260216A: Fermi Gamma-ray Burst Monitor trigger 792969362/260216886 is not a GRB
  16. GRB 260216A: Fermi GBM Final Real-time Localization
  17. EP260214b: Liverpool Telescope optical observations
  18. GRB 260206A: probable hard X-ray burst from 4U 0513-40
  19. EP260214b: Optical upper limit with Kinder observations
  20. EP260214a: Optical upper limits with Kinder observations
  21. EP260214b: EP-FXT follow-up observation
  22. EP260214a / GRB 260214A: Fermi-GBM Sub-Threshold Detection
  23. EP260214b: DDOTI Optical Detection
  24. EP260214b: GROWTH-India Telescope optical upper limit
  25. EP260214a: VLT near-infrared observation
  26. EP260214b: SVOM/VT optical observation
  27. EP260214a: NOT optical upper limits
  28. EP260214a: COLIBRÍ optical upper limits
  29. EP260214b: OHP/T120 optical observations
  30. EP260214a: refined analysis of the EP-FXT observation
  31. EP260214b: LCO optical counterpart detection
  32. EP260214b: VLT/X-shooter spectroscopic redshift z = 1.208
  33. GRB 260211A: SVOM/VT optical counterpart
  34. EP260214b: COLIBRÍ optical observations
  35. EP260214a: SVOM/VT optical upper limits
  36. EP260214b: NOT optical counterpart detection
  37. EP260214b: Einstein Probe detection of a fast X-ray transient
  38. EP260214a: Global MASTER-Net observations report
  39. EP260214a: Einstein Probe detection of an X-ray transient
  40. GRB 260212A: AstroSat CZTI detection
  41. GRB 260212A: Fermi GBM Observation
  42. EP260213a: Liverpool Telescope optical upper limits
  43. EP260213a: Global MASTER-Net observations report
  44. EP260213a: COLIBRÍ optical upper limits
  45. GRB 260212A: GECAM-B observation
  46. EP260213a: Optical upper limits with Kinder observations
  47. EP260213a: SVOM/VT optical upper limit
  48. EP260213a: Mondy R-band optical upper limit
  49. EP260213a: NUTTelA-TAO Early Optical Limits
  50. EP260213a: SVOM/C-GFT upper limit
  51. EP260213a: refined analysis of the EP-FXT observation
  52. EP260213a: Einstein Probe detection of a fast X-ray transient
  53. EP/WXT 01709258378: NOT optical upper limits
  54. GRB 260212A: SVOM/GRM observation of a long burst
  55. GRB 260213B: Fermi GBM Final Localization
  56. GRB 260213B: BALROG localization (Fermi Trigger 792697214 / GRB 260213736)
  57. GRB 260211A - SVOM/ECLAIRs refined analysis
  58. GRB 260204A: SVOM/ECLAIRs refined analysis
  59. GRB 260213A: Fermi GBM Final Localization
  60. GRB 260211A: EP-FXT follow-up observation
  61. GRB 260211A: SVOM/VT optical observation
  62. GRB 260212A: Glowbug gamma-ray detection
  63. GRB 260211A: GOTO optical upper limit
  64. Fermi GRB 260212A: Global MASTER-Net observations report
  65. GRB 260212A: Fermi GBM Final Real-time Localization
  66. GRB 260211A: LAST optical upper limit
  67. GRB 260210A: SVOM/GRM observation
  68. Fermi GBM Sub-Threshold Detection of GRB 260211A
  69. Konus-Wind detection of GRB 260207B
  70. GRB 260128B: SVOM/ECLAIRs refined analysis
  71. GRID detection of GRB 260207B
  72. GRB 260211A: LCO optical upper limits
  73. GRB260131A/B: 3.6m DOT Optical Observations
  74. GRB 260211A: SVOM/COLIBRÍ (FM-GFT) optical upper limits
  75. Fermi trigger No 792537871: Global MASTER-Net observations report
  76. GRB 260211A: SVOM detection of a burst
  77. Swift Operations Update + Community Forum (Friday, February 13 @ 10:00 AM EST)
  78. Konus-Wind detection of GRB 260209B
  79. GRB 260208A: Swift UVOT detection
  80. Konus-Wind detection of GRB 260127B
  81. EP260209a: COLIBRÍ optical upper limit
  82. Fermi GRB 260210C: Global MASTER-Net observations report
  83. EP260209a: LCO optical upper limits
  84. EP260210a: Global MASTER-Net observations report
  85. EP260210a: refined analysis of the EP-FXT observation
  86. EP260209a: Global MASTER-Net observations report
  87. GRB 260208A: LCO detection of the optical counterpart
  88. EP260209a: Einstein Probe detection of a fast X-ray transient
  89. EP260210a: Optical upper limits with Kinder observations
  90. IPN triangulation of GRB 260207B (short/hard with EE)
  91. GRB 260210C: Fermi GBM Final Real-time Localization
  92. GRB 260210A: Glowbug gamma-ray detection
  93. GRB 260210B: Fermi GBM Final Real-time Localization
  94. EP260210a: SVOM/VT optical upper limit
  95. GRB 260210A: AstroSat CZTI detection
  96. GRB 260208C: AstroSat CZTI detection
  97. EP260210a: COLIBRÍ optical upper limit
  98. EP260210a: SVOM/C-GFT upper limit
  99. GRB 260208B: refined analysis of the EP-FXT observation
  100. EP260210a: Einstein Probe detection of an X-ray transient

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