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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"

27321 results found.

  1. GRB 090309B: Fermi GBM detection
  2. GRB 090309: Swift-XRT refined analysis
  3. GRB 090309: Enhanced Swift-XRT position
  4. GRB 090309, Swift-BAT refined analysis
  5. GRB 090308: GROND observations
  6. GRB 090308: Gemini GMOS Observations
  7. GRB 090309: Swift detection of a burst
  8. GRB 090308B: Fermi GBM detection
  9. GRB 090308: Swift/UVOT Upper Limits
  10. GRB 090307B: Fermi GBM detection
  11. GRB 090306C: Fermi GBM detection
  12. GRB 090307: GROND Upper Limits
  13. GRB 090306B: GROND Upper Limits
  14. GRB 090308: Swift-XRT refined analysis
  15. Radio observation of GRB 090201 with ATCA
  16. Radio observation of GRB 090117 with ATCA
  17. Radio observation of GRB 081226b with ATCA
  18. Radio observation of GRB 081226a with ATCA
  19. Radio observation of GRB 081007 with ATCA
  20. GRB 090308: Swift-BAT refined analysis
  21. GRB 090308: Swift detection of a burst
  22. GRB 090306B: Possible XRT afterglow
  23. GRB 090307: Swift-XRT afterglow confirmation and analysis
  24. GRB 090307: Swift-BAT refined analysis of trigger 345551
  25. GRB 090306B: Burst detection from Swift-BAT slew data
  26. Swift Trigger 345551 is probably not a GRB
  27. IPN localization of short GRB 090305C
  28. GRB 090306: Swift detection of a possible burst
  29. GRB 090305: Swift/UVOT Upper Limits
  30. GRB 090305: Swift-XRT refined analysis
  31. GRB 090305, Swift-BAT refined analysis
  32. GRB 090227A: Suzaku WAM observation of the prompt emission
  33. GRB090305: GMOS-S Candidate Optical Afterglow
  34. GRB 090305: Swift detection of a short burst
  35. GRB 090303: Fermi GBM detection
  36. GRB 090304: Fermi GBM detection
  37. GRB 090301A: Suzaku WAM observation of the prompt emission
  38. GRB 090228B: Fermi GBM detection
  39. GRB 090301A: Swift-BAT refined analysis
  40. GRB 090301B: Fermi GBM detection
  41. GRB 090227B: Fermi GBM detection
  42. Swift_BAT_Lightcurve Notice for Trigger Number 344565 is not valid
  43. GRB 090228: Fermi GBM detection
  44. GRB 090227: Fermi GBM detection
  45. GRB 090206: Fermi GBM detection
  46. SGR J1550-5418
  47. GRB 081211B: Nearby cluster
  48. GRB 090222: Fermi GBM detection
  49. GRB 090219: Fermi GBM detection
  50. Swift Trigger 343319 is not a GRB
  51. GRB 090217: Suzaku WAM observation of the prompt emission
  52. GRB090217: XRT analysis
  53. GRB 090213: Fermi GBM detection
  54. GRB 090217: Fermi GBM detection
  55. SGR activity seen by BAT during ICSP Ionospheric Events
  56. GRB 090207 - Fermi GBM Observations
  57. GRB 090129: Fermi GBM detection
  58. VLA radio upper limit on GRB 090205
  59. GRB 090205: Swift/UVOT Upper Limits
  60. GRB 090205: Swift-XRT refined analysis
  61. GRB 090205: GROND observations and photometric redshift estimate
  62. GRB 090205: VLT candidate afterglow
  63. GRB 090205: Swift-BAT refined analysis
  64. GRB 090205: Enhanced Swift-XRT position
  65. GRB 090205: Swift detection of a burst
  66. GRB 080319B: IceCube upper limit on high-energy neutrino flux
  67. GRB 090131: Suzaku WAM observation of the prompt emission
  68. GRB 090202: Fermi GBM detection
  69. GRB 090131: Fermi GBM detection
  70. GRB 090201: Swift-XRT refined analysis
  71. GRB090201: Swift UVOT upper limits
  72. GRB 090201: object inside the enhanced XRT error circle
  73. GRB 090201: Enhanced Swift-XRT position
  74. GRB 090201: VLT NIR observations
  75. GRB 090201: Swift-BAT refined analysis
  76. GRB 090201: VLT afterglow candidate
  77. GRB 090201: Swift-XRT detection of the possible X-ray afterglow
  78. GRB090113: MAGIC telescope GeV observation
  79. GRB 090201: ROTSE-III Optical Limits
  80. GRB 090126A: Swift/UVOT Upper Limits
  81. Konus-Wind observation of bright burst from AXP/SGR 1E1547.0-5408 on January 29
  82. GRB 090129: Swift-BAT refined analysis
  83. GRB 090129: Swift detection of a burst
  84. Suzaku ToO Observation of AXP 1E 1547.0-5408
  85. Konus-Wind observation of AXP/SGR 1E1547.0-5408 bursting activity
  86. GRB 090102: HST observations and host galaxy
  87. GRB 090126C: Fermi GBM detection
  88. GRB 090126A: Swift-XRT Refined Analysis
  89. GRB 090126B: Fermi GBM detection
  90. GRB 090126: SuperAGILE Localization of a Long GRB
  91. GRB 090118: no afterglow candidate
  92. GRB 090123: GROND detection
  93. 1E1547.0-5408: Swift detection of dust halo
  94. GRB 090123: Swift XRT refined analysis
  95. GRB 090123: Swift/UVOT Observations
  96. AXP 1E1547.0-5408: Suzaku WAM detections of the current activity
  97. GRB 090123: Swift-BAT refined analysis
  98. GRB090123: Enhanced Swift-XRT position
  99. GRB 090123: Swift detection of a burst
  100. AXP 1E1547.0-5408: long bursts with INTEGRAL SPI-ACS

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