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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"

20502 results found.

  1. GRB 090429B: Gemini-N further nIR observations
  2. GRB 090429A: GROND upper limits
  3. GRB 090429A: Enhanced Swift-XRT position
  4. Konus-Wind observation of very bright GRB 090427
  5. GRB 090418A BVRcIc field calibration
  6. GRB 090429B: RIMOTS optical upper limits
  7. GRB 090429B: Swift-BAT refined analysis
  8. GRB 090429B: Enhanced Swift-XRT position
  9. GRB090429B: Gemini-N infrared IR candidate
  10. GRB 090429B: VLT upper limits
  11. GRB 090429B: GROND Observations
  12. GRB 090429B: Super-LOTIS early observations
  13. GRB 090429B: Swift detection of a burst
  14. GRB 090429: Swift detection of a burst
  15. GRB 090424 : Multiband Optical observation from Nainital
  16. IPN triangulation of very bright GRB 090427
  17. GRB 090423: CARMA mm observations
  18. GRB 090426: GROND Observations of the Optical/NIR Afterglow
  19. GRB 090423: GROND second epoch imaging and refined SED
  20. Detection of bright radio afterglow of GRB 090424 with the VLA
  21. GRB 090426: Enhanced Swift-XRT position
  22. GRB090426: Observation for Optical counterpart from MIRO
  23. GRB 090426, RIMOTS optical upper limits
  24. GRB 090426: Swift detection of a burst with an optical counterpart
  25. GRB 090424: MASTER-Net prompt optical limit
  26. VLA radio observation of high-z GRB 090423
  27. GRB 090424: THO optical observations
  28. GRB 090424: GROND Observations of the Optical/NIR Afterglow
  29. GRB 090423: Y-band field calibration update/correction
  30. GRB 090424 : TAOS optical detection
  31. GRB 090424: Liverpool Telescope observations
  32. GRB 090424: Optical observations from 1.23m CAHA
  33. GRB 090423: energetic, luminosity and jet break
  34. GRB 090424: MASTER-Net prompt optical observations
  35. GRB 090424: Enhanced Swift-XRT position
  36. GRB 090424: Swift detection of a burst with an optical counterpart
  37. GRB090423: Y-band field calibration
  38. GRB 090423 limiting magnitudes
  39. GRB 090423: Near infrared observation at Okayama Observatory
  40. GRB 090423: Deep z-band upper limit and confirmation of photo-z
  41. GRB 090423: GROND detection and preliminary photo-z
  42. GRB 090423: NOT z-band limit
  43. GRB090418A Rc-band photometry
  44. GRB 090423: NIR photometry and evidence for spectral break
  45. GRB090423, RIMOTS optical upper limits
  46. GRB 090423: Enhanced Swift-XRT position
  47. GRB 090423: Swift-BAT refined analysis
  48. GRB 090422: Swift/UVOT Upper Limits
  49. GRB 090423: UKIRT K-band observations
  50. GRB 090423: P60 Observations
  51. GRB 090418A: R and I band observation
  52. GRB 090423: Swift detection of a burst
  53. GRB 090422: Enhanced Swift-XRT position
  54. GRB 090418B: RTT150 optical observations
  55. GRB 080410: GAO 150cm telescope Optical Observation
  56. GRB 080408A: GAO 150cm telescope Optical Observation
  57. GRB 090422: Swift detection of a burst
  58. GRB 090418A: Swift/UVOT Detection of the Neighbouring Galaxy
  59. GRB 090418B: GRAS002 observatios
  60. GRB 090418A: optical observations
  61. GRB 090418B: GROND observations
  62. GRB 090419: Swift/UVOT Observations
  63. GRB 090418B: Faulkes Telescope North observations
  64. GRB 090418A: Swift/UVOT Observations
  65. GRB 090417B: Swift/UVOT Upper Limits
  66. GRB 090419: Swift-XRT refined analysis
  67. GRB 090419: GROND detection of afterglow candidate
  68. GRB 090418: Optical observations with MITSuME Okayama and Ishigaki 1m telescope
  69. VLA radio detection of GRB 090418
  70. VLA radio upper limit on GRB 090417B
  71. GRB 090419: Enhanced Swift-XRT position
  72. GRB 090418: Swift XRT refined analysis
  73. GRB 090419: Swift detection of a burst
  74. VLA observations of short burst GRB 090417A
  75. GRB 090418B: Detection of a bright burst from Swift-BAT slew data
  76. GRB 090417B: Gemini imaging
  77. GRB 090418: Enhanced Swift-XRT position
  78. GRB 090418: Swift detection of a burst with optical afterglow
  79. GRB 090417B: Subaru NIR Observations
  80. GRB 090417B: MITSuME Okayama optical upper limits
  81. GRB 090417B: optical observations
  82. GRB090417B: optical observations
  83. GRB 090417B: Swift detection of a burst
  84. GRB 090411A: Fermi GBM detection
  85. GRB 090410: GROND upper limits
  86. GRB 090410: MITSuME optical upper limits
  87. GRB 090408b: IPN Triangulation
  88. GRB 090328b: IPN Triangulation
  89. Konus-Wind and Konus-RF observations of GRB 090408b
  90. GRB 090409: Fermi GBM detection
  91. GRB090408, RIMOTS optical upper limits
  92. Swift-BAT trigger 348781: almost certainly not a burst
  93. GRB 090408B: MASTER II-Kourovka optical observations
  94. GRB 090407: GROND upper limits
  95. GRB 090407: VLT observations
  96. GRB 090407: Swift UVOT Upper Limits
  97. GRB 090407: Enhanced Swift-XRT position
  98. GRB 090407: ROTSE-III Optical Limits
  99. GRB 090407: Swift detection of a burst
  100. GRB 090404: GROND upper limits

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