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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"

38609 results found.

  1. GRB 090423 limiting magnitudes
  2. GRB 090423: VLT/ISAAC spectroscopy
  3. GRB 090423: Near infrared observation at Okayama Observatory
  4. GRB 090423: Deep z-band upper limit and confirmation of photo-z
  5. GRB 090423: TNG Amici spectrum
  6. GRB 090423: GROND detection and preliminary photo-z
  7. GRB 090423: NOT z-band limit
  8. GRB 090423: Swift-XRT refined analysis
  9. GRB090423 - Swift/UVOT upper limits.
  10. GRB 090423: NIR photometry and evidence for spectral break
  11. GRB 090422: Swift-XRT refined analysis
  12. GRB090423, RIMOTS optical upper limits
  13. GRB 090423: Enhanced Swift-XRT position
  14. GRB 090422: Swift/UVOT Upper Limits
  15. GRB 090423: UKIRT K-band observations
  16. GRB 090423: P60 Observations
  17. GRB 090423: Faulkes Telescope South observations
  18. GRB 090418A: R and I band observation
  19. GRB 090423: Swift detection of a burst
  20. GRB 090422: Liverpool Telescope possible candidate
  21. GRB 090418A: Konus-Wind and Swift/BAT joint spectral analysis
  22. GRB 090422: Enhanced Swift-XRT position
  23. GRB 090418B: RTT150 optical observations
  24. GRB 090418A: RTT150 optical observations
  25. GRB 090422: Liverpool Telescope observations
  26. GRB 090418B: Suzaku WAM observation of the prompt emission
  27. GRB 090422: Swift detection of a burst
  28. GRB 090418C: Fermi GBM Detection
  29. GRB 090418A: Swift/UVOT Detection of the Neighbouring Galaxy
  30. Swift-BAT trigger 349718 is not a burst
  31. GRB 090418B: GRAS002 observatios
  32. GRB 090417B: Optical observation
  33. GRB 090418A: optical observations
  34. GRB 090418B: GROND observations
  35. GRB 090419: Swift/UVOT Observations
  36. GRB 090418B: Faulkes Telescope North observations
  37. GRB 090418A: Swift/UVOT Observations
  38. GRB 090417B: Swift/UVOT Upper Limits
  39. GRB 090417B Correction to the BAT refined analysis position
  40. GRB 090419: Swift-XRT refined analysis
  41. Konus-Wind observation of GRB 090418B
  42. GRB 090418: Erratum in GCN 9168
  43. GRB 090419: GROND detection of afterglow candidate
  44. GRB 090418: Optical observations with MITSuME Okayama and Ishigaki 1m telescope
  45. VLA radio detection of GRB 090418
  46. VLA radio upper limit on GRB 090417B
  47. GRB 090419: Enhanced Swift-XRT position
  48. GRB 090418: Swift XRT refined analysis
  49. GRB 090418A: ROTSE-III Refined Analysis
  50. GRB 090419: Swift detection of a burst
  51. VLA observations of short burst GRB 090417A
  52. GRB 090417B: Gemini imaging
  53. GRB 090417B: Galaxy redshift
  54. GRB 090417B: Swift-XRT refined analysis
  55. GRB 090418: Enhanced Swift-XRT position
  56. GRB 090417B: Swift-BAT further refined analysis
  57. GRB 090418 Lick Redshift
  58. GRB 090418: ROTSE-III Confirmation of Optical Counterpart
  59. GRB 090418: Swift detection of a burst with optical afterglow
  60. GRB 090418 OA candidate
  61. GRB 090411B: Suzaku WAM observation of the prompt emission
  62. GRB 090411A: Suzaku WAM observation of the prompt emission
  63. GRB 090417B: Subaru NIR Observations
  64. GRB 090417B: Liverpool Telescope observations
  65. GRB 090417B: MITSuME Okayama optical upper limits
  66. GRB090417B: Xinglong TNT optical upper limit
  67. GRB 090417B: optical observations
  68. GRB090417B: optical observations
  69. GRB 090417B: Swift-BAT refined analysis
  70. GRB 090417B: Swift detection of a burst
  71. GRB 090417: Swift detection of a short burst
  72. GRB 090412: Fermi GBM detection
  73. GRB 090411B: Fermi GBM detection
  74. GRB 090411A: Fermi GBM detection
  75. GRB 090410: Suzaku WAM observation of the prompt emission
  76. GRB 090410: GROND upper limits
  77. Fermi GBM trigger 261106787 is not a GRB
  78. GRB 090410: MITSuME optical upper limits
  79. GRB 090408b: IPN Triangulation
  80. GRB 090328b: IPN Triangulation
  81. GRB 090410: Swift detection of a burst
  82. Konus-Wind and Konus-RF observations of GRB 090408b
  83. GRB 090409: Fermi GBM detection
  84. GRB090408, RIMOTS optical upper limits
  85. GRB 090408: Xinglong TNT optical Upper Limit
  86. Swift-BAT trigger 348781: almost certainly not a burst
  87. Fermi GBM Detection of a weak source
  88. GRB 090408B: MASTER II-Kourovka optical observations
  89. GRB 090408: Swift detection of a burst
  90. GRB 090407: GROND upper limits
  91. GRB 090407: VLT observations
  92. GRB 090407: Swift-XRT refined analysis
  93. GRB 090407: Swift UVOT Upper Limits
  94. GRB 090407: Enhanced Swift-XRT position
  95. Konus-Wind and Konus-RF observations of GRB 090406
  96. GRB 090407: ROTSE-III Optical Limits
  97. GRB 090407: Swift detection of a burst
  98. GRB 090404: millimeter detection
  99. GRB 090404: nIR observations at Calar Alto
  100. GRB 090405: Fermi GBM Detection

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