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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"

26120 results found.

  1. GRB 240825A: Upper limits from a neutrino search with IceCube
  2. GRB 240819A as a likely X-Ray Flash
  3. GRB 240828B: Swift ToO observations
  4. SVOM GRB 240821A: optical afterglow discovery
  5. GRB 240821A: the second and third EP-FXT follow-up observations and afterglow candidates
  6. GRB 240825A: GECAM detection
  7. GRB 240824A: GIT optical upper limit
  8. GRB 240819A: Swift afterglow confirmation
  9. GRB 240825A: TNG optical photometry and spectroscopy
  10. GRB 240824B: Ondrejov D50 optical limit
  11. GRB 240825A: KAIT optical observations
  12. GRB 240825A: PRIME near-infrared detection
  13. Konus-Wind detection of GRB 240825A (bright/long)
  14. GRB 240825A: Fermi GBM Observation
  15. GRB 240825A : MISTRAL/T193 OHP optical follow-up of the afterglow
  16. GRB 240825A: AKO Optical Follow-Up Observations
  17. GRB 240825A: AstroSat CZTI detection of the long bright burst
  18. SGR 1E 1841-045 / Kes 73: SVOM/GRM observation
  19. GRB 240825A: Swift/UVOT Detection
  20. GRB 240825A: REM detection of the optical/NIR afterglow
  21. GRB 240825A: Swift-XRT refined Analysis
  22. GRB 240825A: VLT/X-shooter redshift
  23. GRB 240825A: SVOM/C-GFT optical observations
  24. GRB 240825A: Montarrenti Observatory optical observations
  25. GRB 240825A: Enhanced Swift-XRT position
  26. GRB 240825A: MASTER optical counterpart observation
  27. GRB 240825A: Fermi-LAT detection
  28. GRB 240825A: LCO optical observations
  29. GRB 240824B: KAIT optical upper limit
  30. GRB 240824B: Fermi GBM Observation
  31. GRB 240824B: NOT optical upper limit
  32. GRB 240825A: GMG Optical Observation
  33. Swift GRB 240825A: Global MASTER-Net observations report
  34. GRB 240825A: 1.6m Mephisto multi-band detection
  35. GRB 240825A: AKO Optical Afterglow Detection
  36. GRB 240825A: Skynet Optical Afterglow observations
  37. GRB 240825A: Nanshan/HMT optical afterglow observations
  38. GRB 240825A: Swift detection of a burst with a bright optical counterpart
  39. GRB 240824A: Swift-BAT refined analysis
  40. GRB 240824A: SVOM/C-GFT optical upper limit
  41. GRB 240824B: Swift-XRT afterglow detection
  42. GRB 240824A: Swift-XRT observations
  43. GRB 240824B: Swift/BAT arcminute localization of a burst
  44. GRB 240824B: Swift ToO observations
  45. GRB 240824A: Swift/UVOT Upper Limits
  46. GRB 240821A: Swift/UVOT observations of the XRT sources.
  47. GRB 240824A: Retraction of GCN 37255
  48. GRB240824A: GRANDMA/TAROT-TCA Upper Limit
  49. SGR 1E 1841-045 / Kes 73: Leavitt Observatory optical upper limit
  50. GRB 240824A: KAIT optical upper limit
  51. GRB 240824A: Skynet Optical Afterglow Discovery
  52. GRB 240824A: Swift detection of a burst
  53. Swift GRB240824.04: Global MASTER-Net observations report
  54. SGR 1E 1841-045 / Kes 73: Montarrenti Observatory optical upper limits
  55. GRB 240821A: Colibri Optical Upper Limit
  56. GRB 240821A: Swift-XRT observations
  57. GRB 240821A: REM optical/NIR upper limits
  58. GRB 240821A: JinShan optical upper limits
  59. GRB 240809A: Mondy and AbAO Optical Observations
  60. GRB 240821A: SVOM/VT follow-up and optical upper limit
  61. GRB 240821A: GMG Optical Upper Limit
  62. GECAM-B observation of a short burst from SGR 1E 1841-045 / Kes 73
  63. GRB 240821A: Swift ToO observations
  64. Fermi-GBM Observations of the reactivation of SGR 1E 1841-045 / Kes 73
  65. GRB 240821A: EP-FXT follow-up observation and afterglow candidates
  66. Trigger 1249878: Swift detection of another burst from SGR 1E 1841-045 / Kes 73
  67. GRB 240819A: Swift-XRT observations
  68. GRB 240819A: JinShan optical upper limits on one Swift/XRT source
  69. GRB 240819A: KAIT optical upper limit
  70. Trigger 1249653: Swift detection of SGR 1E 1841-045 / Kes 73
  71. GRB 240819A : an X-ray transient detected by SVOM/ECLAIRs
  72. GRB 240819A: TRT optical upper limits on the Swift/XRT and EP/FXT sources
  73. GRB 240819A: Swift ToO observations
  74. GRB GRB 240809A: Osservatorio Astronomico "Nastro Verde" optical observations: detection of an optical counterpart
  75. GRB 240805B: Osservatorio Astronomico Nastro Verde upper limit
  76. EP240802a: Kinder optical, SWIFT-UVOT, and SWIFT-XRT upper limits 6 days after the WXT detection
  77. Konus-Wind detection of GRB 240811A
  78. GRB 240809A : RAPAS follow-up observations
  79. GRB 240811A: Swift-BAT refined analysis
  80. GRB 240809A: Swift-BAT refined analysis
  81. GRB 240811A: Bassano Bresciano Observatory upper limit
  82. GRB 240811A: Swift-XRT refined Analysis
  83. GRB 240811A: Swift/UVOT Upper Limits
  84. GRB 240811A: LCOGT Optical Upper Limit
  85. GRB 240811A: Enhanced Swift-XRT position
  86. Konus-Wind detection of GRB 240809A
  87. Swift GRB 240811A: Global MASTER-Net observations report
  88. GRB 240811A: Swift detection of a burst
  89. GRB240809A: Liverpool Telescope optical follow-up observations
  90. GRB 240809A: REM detection of the optical afterglow
  91. GRB 240809A: Bassano Bresciano Observatory optical observations
  92. GRB 240809A: Conclusive redshift from VLT
  93. GRB 240809A: KAIT optical observations
  94. GRB 240809A: GIT afterglow observations
  95. GRB 240809A: Swift/UVOT Detection
  96. GRB 240809A: Tentative redshift from NOT
  97. GRB 240809A: Swift-XRT refined Analysis
  98. IPN triangulation of GRB 240807A / EP 240807a
  99. Swift GRB 240809A: Global MASTER-Net observations report
  100. GRB 240809A: JinShan optical observations

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