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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"

12332 results found.

  1. GRB 090118: no afterglow candidate
  2. GRB 090123: GROND detection
  3. AXP 1E1547.0-5408: INTEGRAL SPI-ACS confirms activity increase
  4. Trigger 340734: Swift detection of a possible short burst
  5. GRB 090118 (BATSS): GRT Optical Observation
  6. GRB 090118: Swift-XRT observations
  7. GRB090118 Swift/UVOT upper limits
  8. GRB 090118: GROND Upper Limits
  9. GRB 090117: GROND Upper Limits
  10. GRB090117 Swift/UVOT upper limits
  11. GRB090102: MAGIC telescope GeV observation
  12. GRB 090113: Swift UVOT upper limits
  13. GRB 090113: GROND Upper Limits
  14. GRB 090111: Swift UVOT Upper Limits
  15. GRB 090111: Swift detection of a burst
  16. GRB 090107B: Swift/UVOT Observations
  17. VLA radio upper limit on GRB 090102
  18. GRB 090102: GRT Optical Observation
  19. Konus-Wind observation of GRB 090102
  20. GRB 090102: NOT redshift
  21. GRB 081230 Swift/UVOT Observations
  22. GRB 081230: Swift detection of a burst
  23. GRB 081228: Swift/UVOT Upper Limits
  24. GRB 081228: Swift-XRT Team refined analysis
  25. GRB 081228: detection by GROND
  26. GRB 081228: Swift detection of a burst
  27. GRB 081226B: Swift XRT and UVOT upper limits
  28. GRB 081226A: Swift UVOT Upper Limits
  29. GRB 081221: GROND observations
  30. VLA radio upper limit on GRB 081222
  31. GRB081222: Swift/UVOT further observations
  32. Swift/UVOT observations of GRB 081221
  33. GRB081222, optical observation
  34. Konus-Wind observation of GRB 081221
  35. GRB 081221: Swift detection of a burst
  36. GRB 081211B: Further Swift-XRT analysis
  37. Possible GRB 081211B: Swift/UVOT Upper Limits
  38. GRB 081210: Xinglong TNT R band Upper Limits
  39. Konus-Wind observation of GRB 081209
  40. GRB 081204: GROND Observations
  41. GRB081203A: Radio upper limit at 15 GHz
  42. GRB 081204: Swift/UVOT Upper Limits
  43. VLA Radio upper limit on GRB 081203A
  44. Konus-Wind observation of GRB 081203B
  45. GRB 081203B: SDSS upper limits at the position of the optical afterglow
  46. Swift UVOT observations of GRB 081203A
  47. Swift Trigger 335971: Swift/UVOT Observations
  48. VLA Radio upper limit on GRB 081126
  49. GRB 081128A: optical observations
  50. GRB081128: Swift/UVOT Upper Limits
  51. GRB 081128: Swift detection of a burst
  52. GRB 081126: GRT Optical Observation
  53. GRB 081127: Swift/UVOT Upper Limits
  54. GRB 081126: Confirmation of the Optical Afterglow
  55. Konus-Wind observation of GRB 081126
  56. GRB 081127: Swift detection of a burst
  57. GRB 081126: Swift/UVOT Observations
  58. GRB081121: Refined Swift/UVOT observations
  59. GRB081118 : optical upper limit
  60. VLA Radio upper limit on GRB 081118
  61. GRB 081118: Swift UVOT Upper Limits
  62. GRB 081118: Swift detection of a burst
  63. GRB 081025: Swift-XRT further analysis
  64. GRB 081024B: Swift-XRT late-time observations
  65. GRB 081109B: Swift/UVOT refined analysis
  66. GRB 081109A: Faulkes Telescope South observations
  67. GRB 081109: Swift/UVOT upper limits
  68. GRB 081109A optical upper limit
  69. Swift-BAT Trigger 334129: possible burst
  70. GRB 081109: Swift detection of a burst
  71. GRB 081105: GROND Upper Limits
  72. GRB081104: Swift/UVOT Upper Limits
  73. GRB 081102: OPTIMA-Burst optical upper limit
  74. SGR 0501+4516: optical observations in August
  75. GRB 081024B: new Swift-XRT observations
  76. GRB 081029: UVOT Detection of the Optical Afterglow
  77. GRB081028: UVOT detection of a brightening afterglow
  78. Swift UVOT observations of GRB081028
  79. GRB 081025: TLS upper limits
  80. Swift UVOT observations of GRB081025
  81. Swift UVOT observations of GRB081024B
  82. Konus-Wind observation of GRB 081025
  83. Swift UVOT observations of GRB 081024
  84. GRB 081016A: Swift-XRT refined analysis
  85. Swift detection of a possible burst (trigger 332287)
  86. GRB 081016B: Swift/UVOT Upper Limits
  87. GRB 081016B: Swift-XRT Team refined Analysis
  88. GRB 081012: GROND upper limits
  89. GRB 081008 optical upper limit
  90. GRB 081012: Swift/UVOT analysis of initial observations
  91. GRB081011: UVOT detection of an optical afterglow
  92. GRB 081011: Swift detection of a burst
  93. GRB081008: Swift/UVOT observations
  94. GRB 081008: VLT/FORS2 spectroscopy
  95. GRB081007: Swift/UVOT Observations
  96. AXP 1E 1547.0-5408: Swift/UVOT Upper Limits
  97. GRB 081003B: Swift-XRT upper limit
  98. Trigger 330353: Swift detection of a Galactic short soft burst
  99. GRB 081001: Swift UVOT Observations
  100. GRB 080928: VLT redshift

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