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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"

27418 results found.

  1. GRB 090313: Zadko Telescope observations
  2. GRB 090313 - PAIRITEL NIR detections
  3. GRB 090313: Gemini-S redshift
  4. GRB 090313: Swift-XRT refined analysis
  5. GRB 090313: Swift/UVOT upper limits
  6. GRB 090313: Faulkes Telescope North observations
  7. GRB 090306B: Confirmation of the X-ray afterglow
  8. GRB 090313: Swift-BAT refined analysis
  9. GRB 090313: Sustained optical brightness
  10. GRB 090313, GROND observations
  11. GRB 090309, Swift-BAT lag analysis
  12. GRB 090313: Swift detection of a burst
  13. GRB 090313: Swift detection of a burst
  14. Swift trigger 346250 is probably not a burst
  15. GRB090310: Fermi GBM detection
  16. GRB 090205: Zadko Telescope late-time observations
  17. GRB 090309A: GROND upper limits
  18. GRB 090307A: TAROT Calern observatory optical observations
  19. GRB 090309: Swift/UVOT Upper Limits
  20. GRB090305B: Fermi GBM detection
  21. GRB 090309B: Fermi GBM detection
  22. GRB 090309: Swift-XRT refined analysis
  23. GRB 090306B: INTEGRAL SPI-ACS light curve
  24. GRB 090309, Swift-BAT refined analysis
  25. GRB 090308: GROND observations
  26. GRB 090309: Swift detection of a burst
  27. GRB 090308B: Fermi GBM detection
  28. GRB 090308: Swift/UVOT Upper Limits
  29. GRB 090307B: Fermi GBM detection
  30. GRB 090306C: Fermi GBM detection
  31. GRB 090307: GROND Upper Limits
  32. GRB 090306B: GROND Upper Limits
  33. GRB 090308: Swift-XRT refined analysis
  34. ATCA observation of SGR J1550-5418
  35. GRB 090308: Swift-BAT refined analysis
  36. GRB 090308: Swift detection of a burst
  37. GRB 090306B: Possible XRT afterglow
  38. GRB 090307: Swift-XRT afterglow confirmation and analysis
  39. GRB 090307: Swift-BAT refined analysis of trigger 345551
  40. GRB 090306B: Burst detection from Swift-BAT slew data
  41. Swift Trigger 345551 is probably not a GRB
  42. Swift-BAT trigger 345396 is not a GRB
  43. IPN localization of short GRB 090305C
  44. Fermi GBM trigger 090305784 is not a GRB
  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 090305: Magellan confirmation of the optical afterglow
  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. Konus-RF catches first GRB and SGR bursts
  56. GRB 090228B: Fermi GBM detection
  57. Konus-Wind observation of bright short GRB 090227B
  58. IPN localization of short bright GRB 090227B
  59. Konus-Wind observation of GRB 090301A
  60. GRB 090301A: Swift-BAT refined analysis
  61. GRB 090301B: Fermi GBM detection
  62. GRB 090227B: Fermi GBM detection
  63. GRB 090301: Swift detection of a burst
  64. Swift_BAT_Lightcurve Notice for Trigger Number 344565 is not valid
  65. GRB 090228: Fermi GBM detection
  66. GRB 090227: Fermi GBM detection
  67. GRB 090206: Fermi GBM detection
  68. SGR J1550-5418
  69. GRB 081211B: Nearby cluster
  70. Ongoing activity of AXP/SGR 1E1547.0-5408
  71. GRB 090222: Fermi GBM detection
  72. GRB 090219: Fermi GBM detection
  73. Swift Restored
  74. Swift Trigger 343319 is not a GRB
  75. GRB 090217: Suzaku WAM observation of the prompt emission
  76. GRB090217: XRT analysis
  77. Konus-Wind observation of GRB 090217
  78. IPN localization of GRB 090217
  79. GRB 090213: Fermi GBM detection
  80. GRB090217: Fermi-LAT Detection
  81. GRB 090217: Fermi GBM detection
  82. SGR activity seen by BAT during ICSP Ionospheric Events
  83. GRB 090207 - Fermi GBM Observations
  84. Fermi Gamma-ray Burst Monitor trigger 255729682 is not a GRB
  85. GRB 090129: Fermi GBM detection
  86. Fermi Gamma-ray Burst Monitor trigger 255541748 cannot be classified
  87. GRB 090205: Swift/UVOT Upper Limits
  88. GRB 090205: Swift-XRT refined analysis
  89. GRB 090205: GROND observations and photometric redshift estimate
  90. GRB 090205: Swift-BAT refined analysis
  91. GRB 090205: Swift detection of a burst
  92. GRB 090126A: Swift-XRT afterglow confirmation
  93. Fermi Gamma-ray Burst Monitor trigger 255342766 is not a GRB
  94. Konus-Wind observation of GRB 090201
  95. GRB 090202: Fermi GBM detection
  96. GRB 090131: Fermi GBM detection
  97. GRB 090201: Swift-XRT refined analysis
  98. GRB090201: Swift UVOT upper limits
  99. GRB 090201: Swift-BAT refined analysis
  100. GRB 090201: Swift-XRT detection of the possible X-ray afterglow

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