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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"

28078 results found.

  1. GRB 090304: Fermi GBM detection
  2. GRB 090228B: Fermi GBM detection
  3. GRB 090301B: Fermi GBM detection
  4. GRB 090227B: Fermi GBM detection
  5. GRB 090301: Swift detection of a burst
  6. GRB 090228: Fermi GBM detection
  7. GRB 090227: Fermi GBM detection
  8. GRB 090206: Fermi GBM detection
  9. GRB 081211B: Nearby cluster
  10. GRB 090222: Fermi GBM detection
  11. GRB 090219: Fermi GBM detection
  12. GRB 090217: Suzaku WAM observation of the prompt emission
  13. GRB090217: XRT analysis
  14. GRB 090213: Fermi GBM detection
  15. GRB090217: Fermi-LAT Detection
  16. GRB 090217: Fermi GBM detection
  17. SGR activity seen by BAT during ICSP Ionospheric Events
  18. GRB 090129: Fermi GBM detection
  19. VLA radio upper limit on GRB 090205
  20. GRB 090205: VLT optical decay
  21. GRB 090205: Swift/UVOT Upper Limits
  22. GRB 090205: VLT refined redshift
  23. GRB 090205: Swift-XRT refined analysis
  24. GRB 090205: Swift burst of interest
  25. GRB 090205: VLT spectroscopic redshift
  26. GRB 090205: GROND observations and photometric redshift estimate
  27. GRB 090205: VLT candidate afterglow
  28. GRB 090205: Enhanced Swift-XRT position
  29. GRB 090205: Swift detection of a burst
  30. GRB 090126A: Swift-XRT afterglow confirmation
  31. GRB 090202: Fermi GBM detection
  32. GRB 090131: Fermi GBM detection
  33. GRB 090201: Swift-XRT refined analysis
  34. GRB090201: Swift UVOT upper limits
  35. GRB 090201: object inside the enhanced XRT error circle
  36. GRB 090201: Enhanced Swift-XRT position
  37. GRB 090201: VLT NIR observations
  38. GRB 090201: VLT afterglow candidate
  39. GRB 090201: Swift-XRT detection of the possible X-ray afterglow
  40. GRB 090201: ROTSE-III Optical Limits
  41. GRB 090201: Swift detection of a burst
  42. GRB 090126A: Swift/UVOT Upper Limits
  43. GRB 090129: Swift detection of a burst
  44. GRB 090102: HST observations and host galaxy
  45. GRB 090126C: Fermi GBM detection
  46. GRB 090126A: Swift-XRT Refined Analysis
  47. GRB 090126B: Fermi GBM detection
  48. Konus-Wind detection of very bright SGR-like burst on January 25, 2009
  49. GRB 090118: no afterglow candidate
  50. GRB 090123: GROND detection
  51. 1E1547.0-5408: Swift detection of dust halo
  52. GRB 090123: Swift XRT refined analysis
  53. GRB 090123: Swift/UVOT Observations
  54. GRB090123: Enhanced Swift-XRT position
  55. GRB 090123: Swift detection of a burst
  56. GRB 090118: Swift XRT Observations - Confirmation of an Afterglow
  57. AXP 1E1547.0-5408: Fermi GBM detection of additional bursts
  58. Trigger 340734: Swift detection of a possible short burst
  59. AXP 1E1547.0-5408 activity with SGR bursts
  60. GRB 090118: Subaru NIR Observation
  61. GRB 090118: KPNO 4m 2nd Epoch Observations
  62. GRB 090118 (BATSS): GRT Optical Observation
  63. GRB 090118: KPNO 4m Detection of Candidate Afterglow
  64. GRB 090118: Swift-XRT observations
  65. GRB 090118: Possible burst detection from Swift-BAT slew data
  66. GRB 090117B : Fermi GBM detection
  67. GRB 090117: confirmation of the X-ray afterglow
  68. GRB 090117C - Fermi GRB Detection
  69. GRB 090117: GROND Upper Limits
  70. GRB090117 Swift/UVOT upper limits
  71. GRB090117: Swift-XRT detection of a possible candidate afterglow
  72. GRB 090113: LOAO Detection Limits in R, I, z, Y-band
  73. GRB 090113: Swift UVOT upper limits
  74. GRB 090113: GROND Upper Limits
  75. GRB 090113: Swift-XRT refined analysis
  76. GRB 090113: Observations from NOT
  77. GRB 090113: Enhanced Swift-XRT position
  78. GRB090113: XRT position
  79. GRB 090112B: Fermi GBM Detection
  80. GRB 090113: Swift detection of a burst
  81. GRB 090112: Fermi GBM detection
  82. GRB 090109: Fermi GBM detection
  83. GRB 090108B: Fermi GBM detection
  84. GRB 090111: Swift UVOT Upper Limits
  85. GRB 090108: Fermi GBM Detection
  86. GRB 090111: Swift-XRT refined analysis
  87. GRB 090111: Enhanced Swift-XRT position
  88. GRB 090111: Swift detection of a burst
  89. GRB090107B: Fermi GBM Detection
  90. GRB 090102: WSRT Radio Observations
  91. GRB 090107B: Swift XRT afterglow confirmation
  92. GRB 090107B: Swift/UVOT Observations
  93. GRB 090107B: Swift-XRT detection of possible afterglow
  94. GRB 090107B optical observations
  95. Fermi/GBM detection of GRB 081226A
  96. Fermi/GBM detection of GRB 081225
  97. GRB 090107: Swift detection of a burst
  98. GRB 081231: Fermi GBM Detection
  99. GRB 090102: optical decay
  100. VLA radio upper limit on GRB 090102

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