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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"

27251 results found.

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

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