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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"

27252 results found.

  1. GRB 240819A as a likely X-Ray Flash
  2. GRB 240821A: PRIME near-infrared observations
  3. Fermi GRB 240828A: Global MASTER-Net observations report
  4. Fermi trigger No 746438824: Global MASTER-Net observations report
  5. GRB 240828B : Detection of a possible very soft X-ray transient by SVOM/ECLAIRs
  6. GRB 240828A: Fermi GBM Final Real-time Localization
  7. GRB 240821A: the second and third EP-FXT follow-up observations and afterglow candidates
  8. GRB 240825A: GECAM detection
  9. GRB 240824A: GIT optical upper limit
  10. GRB 240825A: NUTTelA-TAO / BSTI Optical Limits
  11. GRB 240825A: GMG Continued Optical Observation on the Second Night
  12. GRB 240824B: Ondrejov D50 optical limit
  13. GRB 240825A: Fermi GBM Observation
  14. GRB 240825A : MISTRAL/T193 OHP optical follow-up of the afterglow
  15. GRB 240825A: AKO Optical Follow-Up Observations
  16. GRB 240825A: AstroSat CZTI detection of the long bright burst
  17. SGR 1E 1841-045 / Kes 73: SVOM/GRM observation
  18. GRB 240825A: Swift/UVOT Detection
  19. GRB 240825A: REM detection of the optical/NIR afterglow
  20. GRB 240825A: Swift-XRT refined Analysis
  21. GRB 240825A: VLT/X-shooter redshift
  22. GRB 240825A: SVOM/C-GFT optical observations
  23. GRB 240825A: Montarrenti Observatory optical observations
  24. GRB 240825A: Fermi-LAT detection
  25. GRB 240825A: LCO optical observations
  26. SGR 1E 1841-045 / Kes 73 (Trigger 1249878): Osservatorio Atronomico Nastro Verde optical upper limit
  27. GRB 240824B: Fermi GBM Observation
  28. Fermi GRB 240825A: Global MASTER-Net observations report
  29. SGR 1E 1841-045 / Kes 73 (Trigger 1249653) - Osservatorio Astronomico Nastro Verde upper limit
  30. GRB 240824B: NOT optical upper limit
  31. GRB 240825A: GMG Optical Observation
  32. Swift GRB 240825A: Global MASTER-Net observations report
  33. GRB 240825A: AKO Optical Afterglow Detection
  34. GRB 240825A: Skynet Optical Afterglow observations
  35. GRB 240825A: Nanshan/HMT optical afterglow observations
  36. GRB 240825A: Swift detection of a burst with a bright optical counterpart
  37. GRB 240825A: Fermi GBM Final Real-time Localization
  38. GRB 240824A: Swift-BAT refined analysis
  39. GRB 240824B: Swift/BAT arcminute localization of a burst
  40. Fermi GRB 240824C: Global MASTER-Net observations report
  41. GRB 240824C: Fermi GBM Final Localization
  42. GRB 240824A: Swift/UVOT Upper Limits
  43. GRB 240821A: Swift/UVOT observations of the XRT sources.
  44. GRB 240824B: Fermi GBM Final Real-time Localization
  45. GRB 240824A: Retraction of GCN 37255
  46. GRB240824A: GRANDMA/TAROT-TCA Upper Limit
  47. SGR 1E 1841-045 / Kes 73: Leavitt Observatory optical upper limit
  48. GRB 240824A: Skynet Optical Afterglow Discovery
  49. GRB 240824A: Swift detection of a burst
  50. Swift GRB240824.04: Global MASTER-Net observations report
  51. SGR 1E 1841-045 / Kes 73: Montarrenti Observatory optical upper limits
  52. GRB 240821A: Colibri Optical Upper Limit
  53. GRB 240821A: REM optical/NIR upper limits
  54. GRB 240821A: LCO optical observations
  55. GRB 240821A: JinShan optical upper limits
  56. GRB 240809A: Mondy and AbAO Optical Observations
  57. GRB 240821A: SVOM/VT follow-up and optical upper limit
  58. GRB 240821A: GMG Optical Upper Limit
  59. Fermi GRB 240821A: Global MASTER-Net observations report
  60. GECAM-B observation of a short burst from SGR 1E 1841-045 / Kes 73
  61. GRB 240821A: Fermi GBM Observation
  62. Fermi trigger No 745964969: Global MASTER-Net observations report
  63. Fermi trigger No 745925274: Global MASTER-Net observations report
  64. Fermi trigger No 746019401: Global MASTER-Net observations report
  65. Fermi-GBM Observations of the reactivation of SGR 1E 1841-045 / Kes 73
  66. Fermi trigger No 745935375: Global MASTER-Net observations report
  67. GRB 240821A: EP-FXT follow-up observation and afterglow candidates
  68. Fermi GRB 240821B: Global MASTER-Net observations report
  69. EP240801a: Keck/LRIS spectroscopic redshift confirmation
  70. GRB 240821A: SVOM/GRM observation
  71. GRB 240821A: SVOM/GRM observation
  72. GRB 240821A: GRANDMA/LesMakes-T60 Upper Limit
  73. GRB 240821B: Fermi GBM Final Localization
  74. Fermi trigger No 745866488: Global MASTER-Net observations report
  75. Trigger 1249878: Swift detection of another burst from SGR 1E 1841-045 / Kes 73
  76. GRB 240821A: BALROG localization (Fermi Trigger 745958167 / GRB 240821775)
  77. GRB 240821A : a likely short GRB detected by SVOM/ECLAIRs
  78. GRB 240821A: Fermi GBM Final Real-time Localization
  79. GRB 240820B: SVOM/GRM observation
  80. EP240820a: TRT optical upper limit
  81. EP240820a: EP detection of a fast X-ray transient
  82. GRB 240819A: KAIT optical upper limit
  83. Trigger 1249653: Swift detection of SGR 1E 1841-045 / Kes 73
  84. Fermi trigger No 745873283: Global MASTER-Net observations report
  85. Fermi trigger No 745871958: Global MASTER-Net observations report
  86. GRB 240819A : an X-ray transient detected by SVOM/ECLAIRs
  87. GRB 240819A: X-ray follow-up observation with EP-FXT
  88. Fermi Gamma-ray Burst Monitor trigger 745811685 / 240820080 is not a GRB
  89. GRB 240820A: Fermi GBM Final Real-time Localization
  90. GRB 240814A: SVOM/GRM observation
  91. GRB 240814C: SVOM/GRM observation
  92. EP240816a: BOOTES-6/DPRT optical upper limit
  93. GRB 240815A: SVOM/GRM observation
  94. GRB 240817A: Fermi GBM Final Real-time Localization
  95. Integral GRB240816.79: Global MASTER-Net observations report
  96. GRB GRB 240809A: Osservatorio Astronomico "Nastro Verde" optical observations: detection of an optical counterpart
  97. GRB 240805B: Osservatorio Astronomico Nastro Verde upper limit
  98. EP240816b: KAIT optical upper limit
  99. Fermi trigger No 745501396: Global MASTER-Net observations report
  100. EP240816a: EP detection of a fast X-ray transient and follow-up observation

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