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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

28057 results found.

  1. GRB 090418B: GRAS002 observatios
  2. GRB 090418B: GROND observations
  3. GRB 090419: Swift/UVOT Observations
  4. GRB 090418B: Faulkes Telescope North observations
  5. GRB 090418A: Swift/UVOT Observations
  6. GRB 090417B: Swift/UVOT Upper Limits
  7. GRB 090417B Correction to the BAT refined analysis position
  8. GRB 090419: Swift-XRT refined analysis
  9. Konus-Wind observation of GRB 090418B
  10. GRB 090419: GROND detection of afterglow candidate
  11. GRB 090418: Optical observations with MITSuME Okayama and Ishigaki 1m telescope
  12. GRB 090419: Swift-BAT refined analysis
  13. VLA radio detection of GRB 090418
  14. VLA radio upper limit on GRB 090417B
  15. GRB 090419: Enhanced Swift-XRT position
  16. GRB 090418: Swift XRT refined analysis
  17. GRB 090419: Swift detection of a burst
  18. VLA observations of short burst GRB 090417A
  19. GRB 090418B: Detection of a bright burst from Swift-BAT slew data
  20. GRB 090417B: Gemini imaging
  21. GRB 090418: Swift-BAT refined analysis
  22. GRB 090417B: Swift-XRT refined analysis
  23. GRB 090418: Enhanced Swift-XRT position
  24. GRB 090418: Swift detection of a burst with optical afterglow
  25. GRB 090411B: Suzaku WAM observation of the prompt emission
  26. GRB 090411A: Suzaku WAM observation of the prompt emission
  27. GRB 090417B: Subaru NIR Observations
  28. GRB 090417B: MITSuME Okayama optical upper limits
  29. GRB 090417B: optical observations
  30. GRB090417B: optical observations
  31. GRB 090417B: Swift-BAT refined analysis
  32. GRB 090417A: Swift-BAT refined analysis
  33. GRB 090417A: Early-type nature of the putative host
  34. GRB 090417A: nearby galaxy redshift
  35. GRB 090417B: Swift detection of a burst
  36. GRB 090412: Fermi GBM detection
  37. GRB 090411B: Fermi GBM detection
  38. GRB 090411A: Fermi GBM detection
  39. GRB 090410: Suzaku WAM observation of the prompt emission
  40. GRB 090410: GROND upper limits
  41. GRB 090410: MITSuME optical upper limits
  42. GRB 090408b: IPN Triangulation
  43. GRB 090328b: IPN Triangulation
  44. GRB 090410: Swift-BAT refined analysis
  45. GRB 090409: Fermi GBM detection
  46. GRB090408, RIMOTS optical upper limits
  47. Swift-BAT trigger 348781: almost certainly not a burst
  48. GRB 090408B: MASTER II-Kourovka optical observations
  49. GRB 090407: GROND upper limits
  50. GRB 090407: VLT observations
  51. GRB 090407: Swift-XRT refined analysis
  52. GRB 090407: Swift UVOT Upper Limits
  53. GRB 090407: Enhanced Swift-XRT position
  54. GRB 090407: Swift-BAT refined analysis
  55. GRB 090407: ROTSE-III Optical Limits
  56. GRB 090407: Swift detection of a burst
  57. GRB 090404: millimeter detection
  58. GRB 090405: Fermi GBM Detection
  59. GRB 090403: Fermi GBM detection
  60. GRB 090404: GROND upper limits
  61. GRB 090404: further NOT observations
  62. Swift/UVOT observations of GRB090404
  63. GRB 090404: NOT observations
  64. GRB 090404: Swift-XRT Team refined analysis
  65. GRB 090404: Swift-BAT refined analysis
  66. GRB 090404: Enhanced Swift-XRT position
  67. GRB 090404: Swift detection of a burst
  68. GRB 090401A: Suzaku WAM observation of the prompt emission
  69. GRB 090401B: Suzaku WAM observation of the prompt emission
  70. GRB 090401B: Xinglong TNT optical Upper Limit
  71. GRB 090401B: VLA radio upper limit
  72. GRB 090401B: Upper limits of MITSuME optical observation
  73. GRB090401B, RIMOTS optical upper limits
  74. GRB 090401B: AGILE refined analysis
  75. GRB 090401B: Swift XRT Refined Analysis
  76. GRB 090331: Fermi GBM detection
  77. Konus-Wind observation of GRB 090401A
  78. GRB 090401B: Enhanced Swift-XRT position
  79. AGILE Gamma-ray detection of GRB 090401B
  80. GRB 090401B: Swift-BAT refined analysis
  81. GRB 090401B: Swift detection of a burst
  82. GRB 090328B: MASTER-Irkutsk prompt optical short burst observations
  83. GRB 090401, Swift-BAT refined analysis
  84. GRB 090323: Further TLS detections - a break?
  85. GRB 090324: Suzaku WAM observation of the prompt emission
  86. GRB 090328: Radio afterglow detection
  87. GRB 090326: Fermi GBM detection
  88. GRB 090328: Fermi GBM Spectral Analysis
  89. GRB 090328B: Fermi GBM Detection
  90. GRB 090330: Fermi GBM detection
  91. GRB 090328: GROND Detection of the Optical/NIR Afterglow
  92. GRB 090328: Swift XRT refined analysis
  93. GRB090323: Optical observations from NOT
  94. GRB 090328: Swift UVOT observations
  95. GRB 090328: Updated position/optical afterglow candidate
  96. Fermi LAT and GBM detections of GRB090328
  97. GRB 090323: Radio afterglow detection
  98. GRB 090327: Fermi GBM detection
  99. GRB 090320B: MASTER-Net prompt optical observations
  100. GRB 090323: Fermi GBM Spectral Analysis

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