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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"

28038 results found.

  1. GRB 090313: Additional Gemini-S photometry
  2. GRB 090313: TAROT La Silla observatory optical detection
  3. GRB 090313: Zadko Telescope observations
  4. GRB 090313 optical observations
  5. GRB 090313: Ongoing plateau phase
  6. GRB 090313: Swift-XRT refined analysis
  7. GRB 090313: Swift/UVOT upper limits
  8. GRB 090313: Swift-BAT refined analysis
  9. GRB 090313, GROND observations
  10. GRB 090309, Swift-BAT lag analysis
  11. Swift trigger 346250 is probably not a burst
  12. GRB090310: Fermi GBM detection
  13. GRB 090205: Zadko Telescope late-time observations
  14. GRB 090309A: GROND upper limits
  15. GRB 090307A: TAROT Calern observatory optical observations
  16. GRB 090309: Swift/UVOT Upper Limits
  17. GRB090305B: Fermi GBM detection
  18. GRB 090309B: Fermi GBM detection
  19. GRB 090309: Swift-XRT refined analysis
  20. GRB 090309: Enhanced Swift-XRT position
  21. GRB 090309, Swift-BAT refined analysis
  22. GRB 090308: GROND observations
  23. GRB 090308: Gemini GMOS Observations
  24. GRB 090309: Swift detection of a burst
  25. GRB 090308B: Fermi GBM detection
  26. GRB 090308: Swift/UVOT Upper Limits
  27. GRB 090307B: Fermi GBM detection
  28. GRB 090306C: Fermi GBM detection
  29. GRB 090307: GROND Upper Limits
  30. GRB 090306B: GROND Upper Limits
  31. GRB 090308: Swift-XRT refined analysis
  32. Radio observation of GRB 090201 with ATCA
  33. Radio observation of GRB 090117 with ATCA
  34. Radio observation of GRB 081226b with ATCA
  35. Radio observation of GRB 081226a with ATCA
  36. Radio observation of GRB 081007 with ATCA
  37. GRB 090308: Swift-BAT refined analysis
  38. GRB 090308: Swift detection of a burst
  39. GRB 090306B: Possible XRT afterglow
  40. GRB 090307: Swift-XRT afterglow confirmation and analysis
  41. GRB 090307: Swift-BAT refined analysis of trigger 345551
  42. GRB 090306B: Burst detection from Swift-BAT slew data
  43. Swift Trigger 345551 is probably not a GRB
  44. IPN localization of short GRB 090305C
  45. GRB 090306: Swift detection of a possible burst
  46. GRB 090305: Swift/UVOT Upper Limits
  47. GRB 090305: Swift-XRT refined analysis
  48. GRB 090305, Swift-BAT refined analysis
  49. GRB 090227A: Suzaku WAM observation of the prompt emission
  50. GRB090305: GMOS-S Candidate Optical Afterglow
  51. GRB 090305: Swift detection of a short burst
  52. GRB 090303: Fermi GBM detection
  53. GRB 090304: Fermi GBM detection
  54. GRB 090301A: Suzaku WAM observation of the prompt emission
  55. GRB 090228B: Fermi GBM detection
  56. GRB 090301A: Swift-BAT refined analysis
  57. GRB 090301B: Fermi GBM detection
  58. GRB 090227B: Fermi GBM detection
  59. Swift_BAT_Lightcurve Notice for Trigger Number 344565 is not valid
  60. GRB 090228: Fermi GBM detection
  61. GRB 090227: Fermi GBM detection
  62. GRB 090206: Fermi GBM detection
  63. SGR J1550-5418
  64. GRB 081211B: Nearby cluster
  65. GRB 090222: Fermi GBM detection
  66. GRB 090219: Fermi GBM detection
  67. Swift Trigger 343319 is not a GRB
  68. GRB 090217: Suzaku WAM observation of the prompt emission
  69. GRB090217: XRT analysis
  70. GRB 090213: Fermi GBM detection
  71. GRB 090217: Fermi GBM detection
  72. SGR activity seen by BAT during ICSP Ionospheric Events
  73. GRB 090207 - Fermi GBM Observations
  74. GRB 090129: Fermi GBM detection
  75. VLA radio upper limit on GRB 090205
  76. GRB 090205: Swift/UVOT Upper Limits
  77. GRB 090205: Swift-XRT refined analysis
  78. GRB 090205: GROND observations and photometric redshift estimate
  79. GRB 090205: VLT candidate afterglow
  80. GRB 090205: Swift-BAT refined analysis
  81. GRB 090205: Enhanced Swift-XRT position
  82. GRB 090205: Swift detection of a burst
  83. GRB 080319B: IceCube upper limit on high-energy neutrino flux
  84. GRB 090131: Suzaku WAM observation of the prompt emission
  85. GRB 090202: Fermi GBM detection
  86. GRB 090131: Fermi GBM detection
  87. GRB 090201: Swift-XRT refined analysis
  88. GRB090201: Swift UVOT upper limits
  89. GRB 090201: object inside the enhanced XRT error circle
  90. GRB 090201: Enhanced Swift-XRT position
  91. GRB 090201: VLT NIR observations
  92. GRB 090201: Swift-BAT refined analysis
  93. GRB 090201: VLT afterglow candidate
  94. GRB 090201: Swift-XRT detection of the possible X-ray afterglow
  95. GRB090113: MAGIC telescope GeV observation
  96. GRB 090201: ROTSE-III Optical Limits
  97. GRB 090126A: Swift/UVOT Upper Limits
  98. Konus-Wind observation of bright burst from AXP/SGR 1E1547.0-5408 on January 29
  99. GRB 090129: Swift-BAT refined analysis
  100. GRB 090129: Swift detection of a burst

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