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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

6667 results found.

  1. GRB 090123: Swift XRT refined analysis
  2. AXP 1E1547.0-5408: Fermi GBM observations
  3. GRB 090118: Swift-XRT observations
  4. GRB090118 Swift/UVOT upper limits
  5. GRB090117 Swift/UVOT upper limits
  6. GRB090117: Swift-XRT detection of a possible candidate afterglow
  7. GRB090102: MAGIC telescope GeV observation
  8. GRB 090113: LOAO Detection Limits in R, I, z, Y-band
  9. GRB 090113: Swift-XRT refined analysis
  10. GRB 090112B: Fermi GBM Detection
  11. GRB 090111: Swift-XRT refined analysis
  12. GRB 090107B: Swift XRT afterglow confirmation
  13. GRB 090107B: Swift-XRT detection of possible afterglow
  14. Fermi/GBM detection of GRB 081226A
  15. Fermi/GBM detection of GRB 081225
  16. GRB 090102: Swift XRT refined analysis
  17. GRB 081230, Swift-BAT refined analysis
  18. GRB081230: Swift-XRT refined analysis
  19. GRB 081226B: Fermi GBM observation
  20. GRB 081228, Swift-BAT refined analysis
  21. GRB 081228: Swift-XRT Team refined analysis
  22. GRB 081226B: Swift XRT and UVOT upper limits
  23. GRB 081226: Swift-XRT refined analysis
  24. GRB 081226: Gemini-South imaging
  25. GRB 081224: Swift-XRT observation
  26. GRB 081224: Fermi GBM Detection & LAT Localization
  27. GRB 081222:Optical afterglow observation
  28. GRB081215A: Fermi-LAT observations
  29. GRB 081211B: Further Swift-XRT analysis
  30. GRB 081215B: Fermi GBM detection
  31. GRB 081211B - possibly a short burst with extended emission
  32. Possible GRB 081211B: Swift/UVOT Upper Limits
  33. Possible GRB 081211B - Swift-XRT analysis
  34. GRB 081211: Swift XRT refined analysis
  35. GRB 081210: Swift-XRT refined analysis
  36. GRB 081206C: Fermi GBM detection
  37. GRB 081128: Optical afterglow observations
  38. GRB081203A: Radio upper limit at 15 GHz
  39. GRB 081204: Swift XRT afterglow confirmation
  40. Swift-XRT observations of GRB 081203B
  41. GRB081203A: Swift-XRT refined analysis
  42. GRB 081203B: Swift-XRT candidate afterglow.
  43. GRB 081130B: MASTER prompt optical observations
  44. GRB 081130B: Fermi GBM detection
  45. GRB 081122B: Fermi GBM Detection
  46. GRB 081128: Swift-XRT refined analysis
  47. GRB 081127: Swift-XRT refined analysis
  48. GRB 081126: Swift-XRT refined analysis
  49. GRB 081121: Swift-XRT refined analysis
  50. GRB 081118: Swift-XRT refined analysis
  51. GRB 081118: Swift UVOT Upper Limits
  52. GRB 081109A: confirmation of possible detection host galaxy
  53. Further Swift-XRT observations of the probable GRB 081105.
  54. GRB 081025: Swift-XRT further analysis
  55. GRB 081024B: Swift-XRT late-time observations
  56. GRB 081109A: Swift-XRT refined analysis
  57. GRB 081028 - PAIRITEL NIR detection
  58. GRB 081024C: Fermi Gamma-ray Burst Monitor detection
  59. GRB 081104: refined XRT analysis
  60. Fermi Detection of GRB 081102
  61. GRB 081102: Swift-XRT refined analysis
  62. GRB 081101 (or SGR 0623-0006 ): Fermi GBM detection
  63. SGR 0623-0006 or GRB 081101: Swift-XRT refined analysis
  64. GRB 081024B: new Swift-XRT observations
  65. GRB 081029: Swift-BAT refined analysis
  66. GRB081029: Swift XRT refined analysis
  67. GRB 081029: UVES/VLT Absorption Redshift
  68. GRB 081028B: Fermi GBM detection
  69. GRB 081028: Swift-XRT refined analysis
  70. Fermi LAT/GBM short-hard GRB 081024B: Possible TLS Afterglow (Corrected)
  71. Fermi LAT/GBM short-hard GRB 081024B: Possible TLS Afterglow
  72. GRB 081024B: Swift-XRT further observations
  73. Swift UVOT observations of GRB081024B
  74. GRB 081025: Swift-XRT position
  75. GRB 081024B: Swift-XRT observations
  76. GRB 081024B: Fermi Gamma-ray Burst Monitor detection
  77. Fermi-LAT observation of GRB 081024B
  78. GRB 081016A: Swift-XRT refined analysis
  79. GRB 081011: Swift XRT refined analysis
  80. GRB 081016B: Swift-XRT Team refined Analysis
  81. GRB 081016: Swift-XRT candidate afterglow detection
  82. GRB 081008: Swift-XRT Refined Analysis
  83. GRB081006B: Fermi GBM detection
  84. GRB081006: Fermi GBM detection
  85. GRB 081007: Swift-XRT Team refined analysis
  86. GRB081003C: GLAST Burst Monitor detection
  87. GRB 081003B: Swift-XRT upper limit
  88. GRB 081003A: Swift-XRT Team position and analysis
  89. GRB 080928: Fermi GBM detection
  90. AXP 1E1547.0-5408 (SGR 1550-5418): Fermi GBM detection
  91. GRB 081001: Swift UVOT Observations
  92. GRB 081001: Swift-XRT position
  93. GRB 080928: Swift-XRT refined analysis
  94. GRB 080925: Fermi GBM Detection
  95. Swift trigger 325707: Swift-XRT upper limit
  96. GRB 080913B: Fermi GBM detection
  97. GRB 080919: Swift/UVOT Refined Analysis
  98. GRB 080919: Swift-XRT refined analysis
  99. GRB 080916C: IRSF/SIRUS NIR Observation
  100. GRB 080916C: Swift XRT refined analysis

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