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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"
  1. GRB 100508A: GROND Detection of the optical afterglow
  2. GRB 100508A: Swift-XRT Refined analysis
  3. GRB 100508A: Swift-BAT refined analysis
  4. GRB 100508A: Enhanced Swift-XRT position
  5. GRB100508A: Swift/UVOT Detection of the Afterglow
  6. GRB 100508A: ROTSE-III Optical Limits
  7. GRB 100508A: Swift detection of a burst
  8. GRB 100418A: Keck imaging
  9. GRB 100418A: RTT150 optical observations
  10. Fermi Gamma-ray Burst Monitor trigger 294712621 is not a GRB
  11. Swift-BAT refined analysis of trigger 421262
  12. GRB 100504A: Fermi GBM observation
  13. An SGR-like burst from the magnetar 1E 1841-04.5 in Kes 73
  14. GRB 100504A: Swift/UVOT Observations
  15. GRB 100418A: Flattening of the Swift/UVOT Optical Light Curve
  16. GRB 100504A: Swift-XRT refined analysis
  17. GRB 100504A: Enhanced Swift-XRT position
  18. GRB 100504A: GROND Upper limits
  19. GRB 100504A: Swift-BAT refined analysis
  20. GRB 100504A: SARA-South Upper Limit
  21. GRB 100503A: Fermi GBM detection
  22. GRB 100504A: UVOT-enhanced XRT position
  23. GRB 100504A: Swift detection of a burst
  24. Swift-BAT trigger 421072 is not astrophyical
  25. INTEGRAL observations of Swift GRB trigger 421072
  26. GRB100423A : Suzaku WAM observation of the prompt emission
  27. Trigger 421072: Possible Swift detection of a GRB or transient
  28. GRB 100420A: EVLA radio observations
  29. GRB 100420A: Gemini discovery of infrared afterglow
  30. GRB 100423A: xinglong TNT optical upper limit
  31. GRB 100420A: Terskol optical upper limit
  32. GRB 100427A: Swift XRT and UVOT Upper Limits
  33. GRB 100427A: Fermi GBM detection
  34. GRB 100424a. Radio observations
  35. GRB 100418A: RTT150 optical observations
  36. GRB 100427A detected in ground analysis of Swift BAT data
  37. GRB 100414A : EVLA Radio Detection
  38. GRB 100414A : WSRT Radio Detection
  39. Konus-Wind observation of GRB 100423A
  40. GRB 100423A: CrAO optical observations
  41. GRB 100418A: Terskol optical observations
  42. GRB 100424A: CrAO optical observations
  43. GRB 100424A: NIR Afterglow Confirmation
  44. GRB 100425A: Swift XRT refined analysis
  45. GRB 100424A: Gemini/NIRI H-band observations
  46. GRB100425A: Swift/UVOT Upper Limits
  47. GRB 100424A: Swift/UVOT Upper Limits
  48. GRB 100424A: Liverpool Telescope Upper Limits
  49. GRB 100425A: Enhanced Swift-XRT position
  50. GRB 100425A: Swift-BAT refined analysis
  51. GRB 100425A: VLT/X-shooter redshift
  52. GRB 100425A: GROND afterglow observation
  53. GRB 100424A: Gemini/NIRI Candidate Afterglow
  54. GRB 100424A: D50 optical limits
  55. GRB 100425A: candidate optical afterglow from the VLT
  56. GRB100424A: MITSuME optical upper limits
  57. GRB100423A: MITSuME optical upper limits
  58. GRB 100424A : Lulin early z'-band upper limit
  59. GRB 100424A: GROND Upper Limits
  60. GRB 100424A: PAIRITEL NIR Upper Limits
  61. GRB 100424A: Swift-XRT refined analysis
  62. GRB 100425A: Swift detection of a burst
  63. GRB 100424A: WHT z-band observations
  64. GRB 100424A: NOT optical observations
  65. GRB 100424A, Swift-BAT refined analysis
  66. GRB 100424A: Enhanced Swift-XRT position
  67. GRB 100424A: Prompt enhanced Swift-XRT position.
  68. GRB 100424A: Swift detection of a burst
  69. GRB 100420A: GRT Optical Observation
  70. GRB 100418A: ROVOR optical measurements at 35 hours
  71. Swift-BAT refined analysis of trigger 420256
  72. Swift Trigger 420256: D50 optical limits
  73. GRB 100418A: Possible Evidence for a Supernova
  74. GRB 100420A: Swift-BAT refined analysis
  75. GRB 100423B: Fermi GBM detection
  76. GRB 100423A: Swift-BAT refined analysis
  77. Swift Trigger 420256: IAC80 R-band observations
  78. Swift Trigger 420256: BOOTES-2 observations
  79. Swift Trigger 420256: ROTSE-III Optical Limits
  80. Trigger 420256: Swift detection of a possible GRB
  81. GRB 100423A: Skynet/PROMPT Detections
  82. GRB 100423A: GROND discovery of afterglow
  83. GRB 100423A: Swift detection of a burst
  84. Radio afterglow detection of GRB 100418A with the EVLA
  85. GRB 100414A: Radio Afterglow Detection with the Expanded VLA
  86. GRB 100418A: Continued PAIRITEL NIR Observations
  87. GRB 100418A: WSRT Radio Detection
  88. GRB100418A: REM possible afterglow detection
  89. GRB 100418A: Continuing Swift/UVOT Observations
  90. GRB 100418A: further GROND observations and light curve fit
  91. GRB 100418A: RTT150 optical observations
  92. GRB100420A: MITSuME optical upper limits
  93. GRB 100414A: CFHT optical observations
  94. GRB 100420A: Swift/UVOT Upper Limits
  95. GRB 100420A: XRT refined analysis
  96. GRB 100420A: Enhanced Swift-XRT position
  97. GRB 100418A: SARA second epoch
  98. GRB 100420A: SARA Upper Limits
  99. GRB 100418A: RTT150 observations during the optical afterglow maximum
  100. GRB 100418A: optical observations

Advanced

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