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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"
  1. GRB 090307: Swift-XRT afterglow confirmation and analysis
  2. GRB 090307: Swift-BAT refined analysis of trigger 345551
  3. GRB 090306B: Burst detection from Swift-BAT slew data
  4. Swift Trigger 345551 is probably not a GRB
  5. Swift-BAT trigger 345396 is not a GRB
  6. IPN localization of short GRB 090305C
  7. Fermi GBM trigger 090305784 is not a GRB
  8. GRB 090306: Swift detection of a possible burst
  9. GRB 090305: Swift/UVOT Upper Limits
  10. GRB 090305: Swift-XRT refined analysis
  11. GRB 090305, Swift-BAT refined analysis
  12. GRB 090227A: Suzaku WAM observation of the prompt emission
  13. GRB 090305: Magellan confirmation of the optical afterglow
  14. GRB090305: GMOS-S Candidate Optical Afterglow
  15. GRB 090305: Swift detection of a short burst
  16. GRB 090303: Fermi GBM detection
  17. GRB 090304: Fermi GBM detection
  18. GRB 090301A: Suzaku WAM observation of the prompt emission
  19. Konus-RF catches first GRB and SGR bursts
  20. GRB 090228B: Fermi GBM detection
  21. Konus-Wind observation of bright short GRB 090227B
  22. IPN localization of short bright GRB 090227B
  23. Konus-Wind observation of GRB 090301A
  24. GRB 090301A: Swift-BAT refined analysis
  25. GRB 090301B: Fermi GBM detection
  26. GRB 090227B: Fermi GBM detection
  27. GRB 090301: Swift detection of a burst
  28. Swift_BAT_Lightcurve Notice for Trigger Number 344565 is not valid
  29. GRB 090228: Fermi GBM detection
  30. GRB 090227: Fermi GBM detection
  31. GRB 090206: Fermi GBM detection
  32. SGR J1550-5418
  33. GRB 081211B: Nearby cluster
  34. Ongoing activity of AXP/SGR 1E1547.0-5408
  35. GRB 090222: Fermi GBM detection
  36. GRB 090219: Fermi GBM detection
  37. Swift Restored
  38. Swift Trigger 343319 is not a GRB
  39. GRB 090217: Suzaku WAM observation of the prompt emission
  40. GRB090217: XRT analysis
  41. Konus-Wind observation of GRB 090217
  42. IPN localization of GRB 090217
  43. GRB 090213: Fermi GBM detection
  44. GRB090217: Fermi-LAT Detection
  45. GRB 090217: Fermi GBM detection
  46. SGR activity seen by BAT during ICSP Ionospheric Events
  47. Detailed lightcurves of ICSP VLF Observation of SGR/AXP 1E1547.0-5408
  48. GRB 090207 - Fermi GBM Observations
  49. Fermi Gamma-ray Burst Monitor trigger 255729682 is not a GRB
  50. GRB 090129: Fermi GBM detection
  51. VLA radio upper limit on GRB 090205
  52. GRB 090205: VLT optical decay
  53. Fermi Gamma-ray Burst Monitor trigger 255541748 cannot be classified
  54. GRB 090205: Swift/UVOT Upper Limits
  55. GRB 090205: VLT refined redshift
  56. GRB 090205: Swift-XRT refined analysis
  57. GRB 090205: Swift burst of interest
  58. GRB 090205: VLT spectroscopic redshift
  59. GRB 090205: GROND observations and photometric redshift estimate
  60. GRB 090205: VLT candidate afterglow
  61. GRB 090205: Swift-BAT refined analysis
  62. GRB 090205: Enhanced Swift-XRT position
  63. GRB 090205: Swift detection of a burst
  64. GRB 080319B: IceCube upper limit on high-energy neutrino flux
  65. GRB 090131: Suzaku WAM observation of the prompt emission
  66. ICSP VLF observation of the signatures of SGR/AXP 1E1547.0-5408 bursts
  67. GRB 090126A: Swift-XRT afterglow confirmation
  68. Fermi Gamma-ray Burst Monitor trigger 255342766 is not a GRB
  69. Konus-Wind observation of GRB 090201
  70. GRB 090202: Fermi GBM detection
  71. GRB 090131: Fermi GBM detection
  72. GRB 090201: Swift-XRT refined analysis
  73. GRB090201: Swift UVOT upper limits
  74. GRB 090201: object inside the enhanced XRT error circle
  75. GRB 090201: Enhanced Swift-XRT position
  76. GRB 090201: VLT NIR observations
  77. GRB 090201: Swift-BAT refined analysis
  78. GRB 090201: VLT afterglow candidate
  79. GRB 090201: Swift-XRT detection of the possible X-ray afterglow
  80. GRB090113: MAGIC telescope GeV observation
  81. GRB 090201: ROTSE-III Optical Limits
  82. GRB 090201: Swift detection of a burst
  83. GRB 090126A: Swift/UVOT Upper Limits
  84. Konus-Wind observation of bright burst from AXP/SGR 1E1547.0-5408 on January 29
  85. GRB 090129: Swift-BAT refined analysis
  86. GRB 090129: Swift detection of a burst
  87. IBAS Alert N. 5442 is not a GRB
  88. Suzaku ToO Observation of AXP 1E 1547.0-5408
  89. Konus-Wind observation of AXP/SGR 1E1547.0-5408 bursting activity
  90. AXP 1E1547.0-5408: RHESSI observations up to 400 keV
  91. GRB 090102: HST observations and host galaxy
  92. GRB 090126C: Fermi GBM detection
  93. GRB 090126A: Swift-XRT Refined Analysis
  94. GRB 090126B: Fermi GBM detection
  95. GRB 090126: SuperAGILE Localization of a Long GRB
  96. Konus-Wind detection of very bright SGR-like burst on January 25, 2009
  97. GRB 090118: no afterglow candidate
  98. GRB 090123: GROND detection
  99. 1E1547.0-5408: Swift detection of dust halo
  100. GRB 090123: Swift XRT refined analysis

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