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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"

27395 results found.

  1. IPN localization of short GRB 090305C
  2. GRB 090306: Swift detection of a possible burst
  3. GRB 090305: Swift/UVOT Upper Limits
  4. GRB 090305: Swift-XRT refined analysis
  5. GRB 090305, Swift-BAT refined analysis
  6. GRB 090227A: Suzaku WAM observation of the prompt emission
  7. GRB090305: GMOS-S Candidate Optical Afterglow
  8. GRB 090305: Swift detection of a short burst
  9. GRB 090303: Fermi GBM detection
  10. GRB 090304: Fermi GBM detection
  11. GRB 090301A: Suzaku WAM observation of the prompt emission
  12. GRB 090228B: Fermi GBM detection
  13. GRB 090301A: Swift-BAT refined analysis
  14. GRB 090301B: Fermi GBM detection
  15. GRB 090227B: Fermi GBM detection
  16. Swift_BAT_Lightcurve Notice for Trigger Number 344565 is not valid
  17. GRB 090228: Fermi GBM detection
  18. GRB 090227: Fermi GBM detection
  19. GRB 090206: Fermi GBM detection
  20. SGR J1550-5418
  21. GRB 081211B: Nearby cluster
  22. GRB 090222: Fermi GBM detection
  23. GRB 090219: Fermi GBM detection
  24. Swift Trigger 343319 is not a GRB
  25. GRB 090217: Suzaku WAM observation of the prompt emission
  26. GRB090217: XRT analysis
  27. GRB 090213: Fermi GBM detection
  28. GRB 090217: Fermi GBM detection
  29. SGR activity seen by BAT during ICSP Ionospheric Events
  30. GRB 090207 - Fermi GBM Observations
  31. GRB 090129: Fermi GBM detection
  32. VLA radio upper limit on GRB 090205
  33. GRB 090205: Swift/UVOT Upper Limits
  34. GRB 090205: Swift-XRT refined analysis
  35. GRB 090205: GROND observations and photometric redshift estimate
  36. GRB 090205: VLT candidate afterglow
  37. GRB 090205: Swift-BAT refined analysis
  38. GRB 090205: Enhanced Swift-XRT position
  39. GRB 090205: Swift detection of a burst
  40. GRB 080319B: IceCube upper limit on high-energy neutrino flux
  41. GRB 090131: Suzaku WAM observation of the prompt emission
  42. GRB 090202: Fermi GBM detection
  43. GRB 090131: Fermi GBM detection
  44. GRB 090201: Swift-XRT refined analysis
  45. GRB090201: Swift UVOT upper limits
  46. GRB 090201: object inside the enhanced XRT error circle
  47. GRB 090201: Enhanced Swift-XRT position
  48. GRB 090201: VLT NIR observations
  49. GRB 090201: Swift-BAT refined analysis
  50. GRB 090201: VLT afterglow candidate
  51. GRB 090201: Swift-XRT detection of the possible X-ray afterglow
  52. GRB090113: MAGIC telescope GeV observation
  53. GRB 090201: ROTSE-III Optical Limits
  54. GRB 090126A: Swift/UVOT Upper Limits
  55. Konus-Wind observation of bright burst from AXP/SGR 1E1547.0-5408 on January 29
  56. GRB 090129: Swift-BAT refined analysis
  57. GRB 090129: Swift detection of a burst
  58. Suzaku ToO Observation of AXP 1E 1547.0-5408
  59. Konus-Wind observation of AXP/SGR 1E1547.0-5408 bursting activity
  60. GRB 090102: HST observations and host galaxy
  61. GRB 090126C: Fermi GBM detection
  62. GRB 090126A: Swift-XRT Refined Analysis
  63. GRB 090126B: Fermi GBM detection
  64. GRB 090126: SuperAGILE Localization of a Long GRB
  65. GRB 090118: no afterglow candidate
  66. GRB 090123: GROND detection
  67. 1E1547.0-5408: Swift detection of dust halo
  68. GRB 090123: Swift XRT refined analysis
  69. GRB 090123: Swift/UVOT Observations
  70. AXP 1E1547.0-5408: Suzaku WAM detections of the current activity
  71. GRB 090123: Swift-BAT refined analysis
  72. GRB090123: Enhanced Swift-XRT position
  73. GRB 090123: Swift detection of a burst
  74. AXP 1E1547.0-5408: long bursts with INTEGRAL SPI-ACS
  75. AXP 1E1547.0-5408: Fermi GBM detection of additional bursts
  76. GRB 090117C: Suzaku WAM observation of the prompt emission
  77. Trigger 340734: Swift detection of a possible short burst
  78. GRB 090118: Subaru NIR Observation
  79. GRB 090118: KPNO 4m 2nd Epoch Observations
  80. GRB 090118 (BATSS): GRT Optical Observation
  81. GRB 090118: KPNO 4m Detection of Candidate Afterglow
  82. GRB 090118: Swift-XRT observations
  83. GRB090118 Swift/UVOT upper limits
  84. GRB 090118: GROND Upper Limits
  85. GRB 090118: Possible burst detection from Swift-BAT slew data
  86. GRB 090117B : Fermi GBM detection
  87. GRB 090117C - Fermi GRB Detection
  88. GRB 090117 - Fermi GBM Observations
  89. GRB 090117: GROND Upper Limits
  90. GRB090117 Swift/UVOT upper limits
  91. GRB090117: Swift-XRT detection of a possible candidate afterglow
  92. GRB 090117 - SuperAGILE Localization of a long GRB
  93. GRB 090112B: Suzaku WAM observation of the prompt emission
  94. GRB 090113: LOAO Detection Limits in R, I, z, Y-band
  95. GRB 090113: Swift UVOT upper limits
  96. GRB 090113: GROND Upper Limits
  97. GRB 090113: Swift-XRT refined analysis
  98. GRB 090113: Observations from NOT
  99. GRB 090113: Enhanced Swift-XRT position
  100. GRB 090113: Swift-BAT refined analysis

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