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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"

28077 results found.

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

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