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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"

36397 results found.

  1. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  2. GRB 241209D: REM optical/NIR upper limits
  3. Konus-Wind detection of GRB 241209D
  4. GRB 241209B: Swift-XRT afterglow detection
  5. GRB 241209C: Fermi GBM Observation
  6. GRB 241209A: Swift-XRT refined Analysis
  7. Fermi Gamma-ray Burst Monitor trigger 755485387 / 241210044 is not a GRB
  8. GRB 241128A: CrAO ZTSh and Mondy AZT-33IK optical observations
  9. GRB 241209D: AstroSat CZTI detection
  10. GRB 241209A: EP-FXT follow-up observations
  11. GRB 241209B: SVOM/VT afterglow detection
  12. GRB 241207B: Fermi GBM Observation
  13. GRB 241209A: BOOTES-7 and 2.2m CAHA early optical upper limits
  14. GRB 241209D: Swift-XRT refined Analysis
  15. GRB 241209D: Fermi GBM Observation
  16. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  17. GRB 241209D: COLIBRÍ detection of the afterglow
  18. GRB 241209A: COLIBRÍ Optical Upper Limit
  19. Fermi GRB 241209D: Global MASTER-Net observations report
  20. GRB 241209A: Fermi GBM Observation
  21. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  22. GRB 241209A: GRANDMA/TAROT upper limit
  23. GRB 241209B: BOOTES-5 optical upper limit
  24. Swift GRB 241209D: Global MASTER-Net observations report
  25. Fermi GRB 241209C: Global MASTER-Net observations report
  26. Fermi GRB 241209E: Global MASTER-Net observations report
  27. GRB 241209E: Fermi GBM Final Real-time Localization
  28. GRB 241209B: Swift ToO observations
  29. GRB 241209A: REM optical/NIR observations
  30. GRB 241209D: Enhanced Swift-XRT position
  31. GRB 241209C: AstroSat CZTI detection
  32. GRB 241209D: Swift detection of a burst
  33. GRB 241209D: Fermi GBM Final Real-time Localization
  34. GRB 241209A: VLT/X-shooter spectroscopy
  35. GRB 241209A: Enhanced Swift-XRT position
  36. GRB 241114B: cubesat Avion detection
  37. GRB 241209A: VLT optical observations
  38. Fermi GRB 241209A: Global MASTER-Net observations report
  39. GRB 241209C: Fermi GBM Final Real-time Localization
  40. GRB 241209A: GOTO optical upper limits
  41. GRB 241209A: Prompt enhanced Swift-XRT position
  42. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  43. GRB 241209A: Swift detection of a short burst
  44. GRB 241209A: Fermi GBM Final Real-time Localization
  45. Fermi GRB 241207B: Global MASTER-Net observations report
  46. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  47. Fermi Gamma-ray Burst Monitor trigger 755277791/241207641 is not a GRB
  48. GRB 241201A: AstroSat CZTI detection
  49. GRB 241206A: DDOTI Upper Limit on the Afterglow
  50. GRB 241207C: MASTER optical observations
  51. GRB 241207C: Tiled Swift observations
  52. GRB 241207C: MAXI/GSC detection
  53. GRB 241207B: Fermi GBM Final Real-time Localization
  54. Fermi GRB 241207A: Global MASTER-Net observations report
  55. GRB 241206A: Fermi GBM observation
  56. GRB 241206C: SVOM/GRM observation of a likely short burst
  57. GRB 241207A: Fermi GBM Final Real-time Localization
  58. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  59. GRB 241206B: SVOM/MXT observations: a probable flare from the QSO 1ES 1959+650
  60. GRB 241206B: GWAC-F50A optical upper limit
  61. GRB 241206B: SVOM/ECLAIRs detection of a long soft transient
  62. Fermi GRB 241206A: Global MASTER-Net observations report
  63. GRB 241206A: Fermi GBM Final Real-time Localization
  64. GRB 241204A: COLIBRÍ Optical Upper Limit
  65. EP241202b: KAIT optical upper limit
  66. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  67. GRB 241204A: DDOTI Upper Limits on the Afterglow
  68. GRB 241204A: Fermi GBM Observation
  69. Fermi GRB 241204A: Global MASTER-Net observations report
  70. GRB 241130A: CALET Gamma-Ray Burst Monitor detection
  71. GRB 241128A : RAPAS follow-up observations
  72. GRB 241201A: GRBAlpha detection
  73. GRB 241204A: Fermi-LAT detection
  74. EP241202b: Upper limits from Fermi-GBM Observations
  75. Fermi-GBM Sub-Threshold Detection of GRB 241128A
  76. GRB 241113B : RAPAS follow-up observation
  77. Konus-Wind detection of GRB 241130A
  78. EP241201a: BOOTES-5 optical upper limit
  79. IPN triangulation of GRB 241130A
  80. GRB 241130A: EIRSAT-1 GMOD Detection
  81. GRB 241128A: Swift/UVOT Upper Limits
  82. GRB 241130A: Fermi GBM Detection
  83. IceCube-241127A: Upper limits from a search for additional neutrino events in IceCube
  84. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  85. LIGO/Virgo/KAGRA S241102br: GRAWITA wide-field optical observations
  86. GRB 241127B: detection of a long GRB by SVOM/ECLAIRs
  87. GRB241201B: Fermi GBM Final Localization
  88. GRB241201B: Fermi GBM Final Localization
  89. Fermi GRB 241201A: Global MASTER-Net observations report
  90. GRB 241201A: BALROG localization (Fermi Trigger 754757764 / GRB 241201622)
  91. GRB 241130A: Fermi GBM Final Real-time Localization
  92. GRB 241130A: Fermi GBM Final Real-time Localization
  93. GRB 241201A: Fermi GBM Final Real-time Localization
  94. IPN triangulation of GRB 241128B
  95. Konus-Wind detection of GRB 241114B
  96. GRB 241128A: AbAO optical upper limit
  97. GRB 241128C: SVOM/GRM observation
  98. GRB 241128B: SVOM/GRM observation
  99. GRB 241128A: Swift-BAT refined analysis
  100. GRB 241127A: Swift-BAT refined analysis

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