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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

36221 results found.

  1. GRB 100508A: Enhanced Swift-XRT position
  2. GRB100508A: Swift/UVOT Detection of the Afterglow
  3. GRB 100508A: ROTSE-III Optical Limits
  4. GRB 100508A: Swift detection of a burst
  5. GRB 100418A: Keck imaging
  6. GRB 100418A: RTT150 optical observations
  7. Fermi Gamma-ray Burst Monitor trigger 294712621 is not a GRB
  8. GRB 100504A: Fermi GBM observation
  9. GRB 100504A: Swift/UVOT Observations
  10. GRB 100418A: Flattening of the Swift/UVOT Optical Light Curve
  11. GRB 100504A: Swift-XRT refined analysis
  12. GRB 100504A: Enhanced Swift-XRT position
  13. GRB 100504A: GROND Upper limits
  14. GRB 100504A: Swift-BAT refined analysis
  15. GRB 100504A: SARA-South Upper Limit
  16. GRB 100503A: Fermi GBM detection
  17. GRB 100504A: UVOT-enhanced XRT position
  18. GRB 100504A: Swift detection of a burst
  19. Swift-BAT trigger 421072 is not astrophyical
  20. INTEGRAL observations of Swift GRB trigger 421072
  21. GRB100423A : Suzaku WAM observation of the prompt emission
  22. Trigger 421072: Possible Swift detection of a GRB or transient
  23. GRB 100420A: EVLA radio observations
  24. GRB 100420A: Gemini discovery of infrared afterglow
  25. GRB 100423A: xinglong TNT optical upper limit
  26. GRB 100420A: Terskol optical upper limit
  27. GRB 100427A: Swift XRT and UVOT Upper Limits
  28. GRB 100427A: Fermi GBM detection
  29. GRB 100424a. Radio observations
  30. GRB 100418A: RTT150 optical observations
  31. GRB 100427A detected in ground analysis of Swift BAT data
  32. GRB 100414A : EVLA Radio Detection
  33. GRB 100414A : WSRT Radio Detection
  34. Konus-Wind observation of GRB 100423A
  35. GRB 100423A: CrAO optical observations
  36. GRB 100418A: Terskol optical observations
  37. GRB 100424A: CrAO optical observations
  38. GRB 100424A: NIR Afterglow Confirmation
  39. GRB 100425A: Swift XRT refined analysis
  40. GRB 100424A: Gemini/NIRI H-band observations
  41. GRB100425A: Swift/UVOT Upper Limits
  42. GRB 100424A: Swift/UVOT Upper Limits
  43. GRB 100424A: Liverpool Telescope Upper Limits
  44. GRB 100425A: Enhanced Swift-XRT position
  45. GRB 100425A: Swift-BAT refined analysis
  46. GRB 100425A: VLT/X-shooter redshift
  47. GRB 100425A: GROND afterglow observation
  48. GRB 100424A: Gemini/NIRI Candidate Afterglow
  49. GRB 100424A: D50 optical limits
  50. GRB 100425A: candidate optical afterglow from the VLT
  51. GRB100424A: MITSuME optical upper limits
  52. GRB100423A: MITSuME optical upper limits
  53. GRB 100424A : Lulin early z'-band upper limit
  54. GRB 100424A: GROND Upper Limits
  55. GRB 100424A: PAIRITEL NIR Upper Limits
  56. GRB 100424A: Swift-XRT refined analysis
  57. GRB 100425A: Swift detection of a burst
  58. GRB 100424A: WHT z-band observations
  59. GRB 100424A: NOT optical observations
  60. GRB 100424A, Swift-BAT refined analysis
  61. GRB 100424A: Enhanced Swift-XRT position
  62. GRB 100424A: Prompt enhanced Swift-XRT position.
  63. GRB 100424A: Swift detection of a burst
  64. GRB 100420A: GRT Optical Observation
  65. GRB 100418A: ROVOR optical measurements at 35 hours
  66. GRB 100418A: Possible Evidence for a Supernova
  67. GRB 100420A: Swift-BAT refined analysis
  68. GRB 100423B: Fermi GBM detection
  69. GRB 100423A: Swift-BAT refined analysis
  70. Trigger 420256: Swift detection of a possible GRB
  71. GRB 100423A: Skynet/PROMPT Detections
  72. GRB 100423A: GROND discovery of afterglow
  73. GRB 100423A: Swift detection of a burst
  74. Radio afterglow detection of GRB 100418A with the EVLA
  75. GRB 100414A: Radio Afterglow Detection with the Expanded VLA
  76. GRB 100418A: Continued PAIRITEL NIR Observations
  77. GRB 100418A: WSRT Radio Detection
  78. GRB100418A: REM possible afterglow detection
  79. GRB 100418A: Continuing Swift/UVOT Observations
  80. GRB 100418A: further GROND observations and light curve fit
  81. GRB 100418A: RTT150 optical observations
  82. GRB100420A: MITSuME optical upper limits
  83. GRB 100414A: CFHT optical observations
  84. GRB 100420A: Swift/UVOT Upper Limits
  85. GRB 100420A: XRT refined analysis
  86. GRB 100420A: Enhanced Swift-XRT position
  87. GRB 100418A: SARA second epoch
  88. GRB 100420A: SARA Upper Limits
  89. GRB 100418A: RTT150 observations during the optical afterglow maximum
  90. GRB 100418A: optical observations
  91. GRB 100418A: MASTER-Net optical observations
  92. GRB 100414A: Confirmation of the X-ray afterglow
  93. GRB 100418A: VLT optical observations
  94. GRB 100418A: SMA submm detection
  95. GRB 100420A: ROTSE-III Optical Limits
  96. GRB 100420A: Swift detection of a burst
  97. GRB 100418A PAIRITEL NIR Observations
  98. GRB 100418A: ROVOR optical afterglow detection
  99. GRB 100418A: Swift/UVOT Observations
  100. GRB 100418A: Gemini-N redshift confirmation

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Download all Circulars as a .tar.gz archive (updated once a day):
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