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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.

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

18386 results found.

  1. GRB090426: Observation for Optical counterpart from MIRO
  2. GRB 090426, RIMOTS optical upper limits
  3. GRB 090426: Swift detection of a burst with an optical counterpart
  4. GRB 090424: MASTER-Net prompt optical limit
  5. VLA radio observation of high-z GRB 090423
  6. GRB 090424: THO optical observations
  7. GRB 090424: GROND Observations of the Optical/NIR Afterglow
  8. GRB 090423: Y-band field calibration update/correction
  9. GRB 090424 : TAOS optical detection
  10. GRB 090424: Liverpool Telescope observations
  11. GRB 090424: Optical observations from 1.23m CAHA
  12. GRB 090424: MASTER-Net prompt optical observations
  13. GRB 090424: Enhanced Swift-XRT position
  14. GRB 090424: Swift detection of a burst with an optical counterpart
  15. GRB090423: Y-band field calibration
  16. GRB 090423 limiting magnitudes
  17. GRB 090423: Near infrared observation at Okayama Observatory
  18. GRB 090423: Deep z-band upper limit and confirmation of photo-z
  19. GRB 090423: GROND detection and preliminary photo-z
  20. GRB 090423: NOT z-band limit
  21. GRB 090423: Correction to NIR photometry
  22. GRB090418A Rc-band photometry
  23. GRB 090423: NIR photometry and evidence for spectral break
  24. GRB090423, RIMOTS optical upper limits
  25. GRB 090423: Enhanced Swift-XRT position
  26. GRB 090422: Swift/UVOT Upper Limits
  27. GRB 090423: UKIRT K-band observations
  28. GRB 090423: P60 Observations
  29. GRB 090418A: R and I band observation
  30. GRB 090423: Swift detection of a burst
  31. GRB 090422: Enhanced Swift-XRT position
  32. GRB 090418B: RTT150 optical observations
  33. GRB 080410: GAO 150cm telescope Optical Observation
  34. GRB 080408A: GAO 150cm telescope Optical Observation
  35. GRB 090422: Swift detection of a burst
  36. GRB 090418B: GRAS002 observatios
  37. GRB 090418B: GROND observations
  38. GRB 090419: Swift/UVOT Observations
  39. GRB 090418B: Faulkes Telescope North observations
  40. GRB 090418A: Swift/UVOT Observations
  41. GRB 090417B: Swift/UVOT Upper Limits
  42. GRB 090419: GROND detection of afterglow candidate
  43. GRB 090418: Optical observations with MITSuME Okayama and Ishigaki 1m telescope
  44. VLA radio detection of GRB 090418
  45. VLA radio upper limit on GRB 090417B
  46. GRB 090419: Enhanced Swift-XRT position
  47. GRB 090419: Swift detection of a burst
  48. VLA observations of short burst GRB 090417A
  49. GRB 090418B: Detection of a bright burst from Swift-BAT slew data
  50. GRB 090417B: Gemini imaging
  51. GRB 090417B: Swift-XRT refined analysis
  52. GRB 090418: Enhanced Swift-XRT position
  53. GRB 090418: Swift detection of a burst with optical afterglow
  54. GRB 090417B: Subaru NIR Observations
  55. GRB 090417B: MITSuME Okayama optical upper limits
  56. GRB 090417B: optical observations
  57. GRB090417B: optical observations
  58. GRB 090417B: Swift detection of a burst
  59. GRB 090410: GROND upper limits
  60. GRB 090410: MITSuME optical upper limits
  61. GRB 090408b: IPN Triangulation
  62. GRB 090328b: IPN Triangulation
  63. GRB090408, RIMOTS optical upper limits
  64. Swift-BAT trigger 348781: almost certainly not a burst
  65. GRB 090408B: MASTER II-Kourovka optical observations
  66. GRB 090407: GROND upper limits
  67. GRB 090407: VLT observations
  68. GRB 090407: Swift UVOT Upper Limits
  69. GRB 090407: Enhanced Swift-XRT position
  70. GRB 090407: ROTSE-III Optical Limits
  71. GRB 090407: Swift detection of a burst
  72. GRB 090404: nIR observations at Calar Alto
  73. GRB 090404: GROND upper limits
  74. GRB 090404: further NOT observations
  75. Swift/UVOT observations of GRB090404
  76. GRB 090404: NOT observations
  77. GRB 090404: Enhanced Swift-XRT position
  78. GRB 090404: Swift detection of a burst
  79. GRB 090401B: Suzaku WAM observation of the prompt emission
  80. GRB 090401B: Xinglong TNT optical Upper Limit
  81. GRB 090401B: VLA radio upper limit
  82. GRB 090401B: Upper limits of MITSuME optical observation
  83. GRB090401B, RIMOTS optical upper limits
  84. GRB 090401B: Enhanced Swift-XRT position
  85. AGILE Gamma-ray detection of GRB 090401B
  86. GRB 090401B: Swift detection of a burst
  87. GRB 090328B: MASTER-Irkutsk prompt optical short burst observations
  88. GRB 090323: Further TLS detections - a break?
  89. GRB 090328: Radio afterglow detection
  90. GRB 090328: GROND Detection of the Optical/NIR Afterglow
  91. GRB090323: Optical observations from NOT
  92. GRB 090328: Swift UVOT observations
  93. GRB 090328: Updated position/optical afterglow candidate
  94. GRB 090323: Radio afterglow detection
  95. GRB 090320B: MASTER-Net prompt optical observations
  96. GRB 090323: UVOT Detection of Afterglow
  97. GRB 090323: P60 Afterglow Confirmation
  98. GRB 090323: GROND Detection of the Afterglow and Photo-z
  99. GRB 090323: Possible XRT Counterpart
  100. Further 15GHz observations of GRB090313

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