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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"

17827 results found.

  1. GRB 090410: MITSuME optical upper limits
  2. GRB 090408b: IPN Triangulation
  3. GRB 090328b: IPN Triangulation
  4. GRB090408, RIMOTS optical upper limits
  5. Swift-BAT trigger 348781: almost certainly not a burst
  6. GRB 090408B: MASTER II-Kourovka optical observations
  7. GRB 090407: GROND upper limits
  8. GRB 090407: VLT observations
  9. GRB 090407: Swift UVOT Upper Limits
  10. GRB 090407: Enhanced Swift-XRT position
  11. GRB 090407: ROTSE-III Optical Limits
  12. GRB 090407: Swift detection of a burst
  13. GRB 090404: nIR observations at Calar Alto
  14. GRB 090404: GROND upper limits
  15. GRB 090404: further NOT observations
  16. Swift/UVOT observations of GRB090404
  17. GRB 090404: NOT observations
  18. GRB 090404: Enhanced Swift-XRT position
  19. GRB 090404: Swift detection of a burst
  20. GRB 090401B: Suzaku WAM observation of the prompt emission
  21. GRB 090401B: Xinglong TNT optical Upper Limit
  22. GRB 090401B: VLA radio upper limit
  23. GRB 090401B: Upper limits of MITSuME optical observation
  24. GRB090401B, RIMOTS optical upper limits
  25. GRB 090401B: Enhanced Swift-XRT position
  26. AGILE Gamma-ray detection of GRB 090401B
  27. GRB 090401B: Swift detection of a burst
  28. GRB 090328B: MASTER-Irkutsk prompt optical short burst observations
  29. GRB 090323: Further TLS detections - a break?
  30. GRB 090328: Radio afterglow detection
  31. GRB 090328: GROND Detection of the Optical/NIR Afterglow
  32. GRB090323: Optical observations from NOT
  33. GRB 090328: Swift UVOT observations
  34. GRB 090328: Updated position/optical afterglow candidate
  35. GRB 090323: Radio afterglow detection
  36. GRB 090320B: MASTER-Net prompt optical observations
  37. GRB 090323: UVOT Detection of Afterglow
  38. GRB 090323: P60 Afterglow Confirmation
  39. GRB 090323: GROND Detection of the Afterglow and Photo-z
  40. GRB 090323: Possible XRT Counterpart
  41. Further 15GHz observations of GRB090313
  42. X-shooter observations of GRB 090313
  43. GRB090313: radio detection with the VLA
  44. IPN Triangulation of GRB090315 and Tupi Detection of Muon Increase
  45. Further radio observation of GRB 090313
  46. GRB 090313: detection with CARMA in 3mm band
  47. GRB090305B: MASTER-net prompt optical short burst observations
  48. GRB 090313: MITSuME Okayama observation
  49. GRB 090313: Additional Gemini-S photometry
  50. GRB 090313: TAROT La Silla observatory optical detection
  51. GRB 090313: Zadko Telescope observations
  52. GRB 090313: Ongoing plateau phase
  53. GRB 090313: Swift-XRT refined analysis
  54. GRB 090313: Swift/UVOT upper limits
  55. GRB 090313, GROND observations
  56. Swift trigger 346250 is probably not a burst
  57. GRB 090205: Zadko Telescope late-time observations
  58. GRB 090309A: GROND upper limits
  59. GRB 090307A: TAROT Calern observatory optical observations
  60. GRB 090309: Swift/UVOT Upper Limits
  61. GRB 090309B: Fermi GBM detection
  62. GRB 090309: Enhanced Swift-XRT position
  63. GRB 090308: GROND observations
  64. GRB 090308: Gemini GMOS Observations
  65. GRB 090309: Swift detection of a burst
  66. GRB 090308: Swift/UVOT Upper Limits
  67. GRB 090307: GROND Upper Limits
  68. GRB 090306B: GROND Upper Limits
  69. GRB 090308: Swift-XRT refined analysis
  70. GRB 090308: Swift detection of a burst
  71. GRB 090306B: Possible XRT afterglow
  72. GRB 090307: Swift-XRT afterglow confirmation and analysis
  73. Swift Trigger 345551 is probably not a GRB
  74. IPN localization of short GRB 090305C
  75. GRB 090306: Swift detection of a possible burst
  76. GRB 090305: Swift/UVOT Upper Limits
  77. GRB 090305: Swift-XRT refined analysis
  78. GRB090305: GMOS-S Candidate Optical Afterglow
  79. GRB 090305: Swift detection of a short burst
  80. GRB 081211B: Nearby cluster
  81. GRB090217: XRT analysis
  82. SGR activity seen by BAT during ICSP Ionospheric Events
  83. VLA radio upper limit on GRB 090205
  84. GRB 090205: Swift/UVOT Upper Limits
  85. GRB 090205: GROND observations and photometric redshift estimate
  86. GRB 090205: VLT candidate afterglow
  87. GRB 090205: Enhanced Swift-XRT position
  88. GRB 090205: Swift detection of a burst
  89. GRB 080319B: IceCube upper limit on high-energy neutrino flux
  90. ICSP VLF observation of the signatures of SGR/AXP 1E1547.0-5408 bursts
  91. GRB090201: Swift UVOT upper limits
  92. GRB 090201: object inside the enhanced XRT error circle
  93. GRB 090201: Enhanced Swift-XRT position
  94. GRB 090201: VLT NIR observations
  95. GRB 090201: VLT afterglow candidate
  96. GRB 090201: Swift-XRT detection of the possible X-ray afterglow
  97. GRB 090201: ROTSE-III Optical Limits
  98. GRB 090126A: Swift/UVOT Upper Limits
  99. Suzaku ToO Observation of AXP 1E 1547.0-5408
  100. Konus-Wind observation of AXP/SGR 1E1547.0-5408 bursting activity

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