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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.

Advanced Search Examples (click to copy):

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

5819 results found.

  1. GRB 071001: Swift-XRT Team refined analysis
  2. GRB 071001: Swift detection of a burst
  3. GRB 070911, SMARTS optical/IR afterglow observations
  4. GRB 070925: Gemini South Imaging
  5. Recent SGR1806-20 Activity
  6. GRB 070917: Suzaku/WAM observation of the prompt emission
  7. INTEGRAL ToO observations of SGR1806-20
  8. GRB 070920b, SMARTS optical observation
  9. GRB 070920: TAROT Calern observatory optical observations
  10. GRB070917: optical observations
  11. GRB 070917: MITSuME Akeno Ic upper limit
  12. GRB 070911: Suzaku WAM observation of the prompt emission
  13. GRB 070913: Swift-XRT detection of the possible X-ray afterglow
  14. GRB 070913: SMARTS optical/IR observations
  15. GRB 070913: TAROT La Silla observatory optical observations
  16. Intense burst from SGR 1806-20 detected on September 7
  17. GRB 070824 - Combined SuperAGILE/IPN Localization
  18. GRB 070731: Swift/UVOT Upper Limit
  19. GRB 070809: Swift/UVOT Upper Limits
  20. GRB 070809: Keck Imaging
  21. GRB070808 - SDSS Pre-Burst Observations
  22. GRB 070808: Swift detection of a burst
  23. Swift trigger on 4U 1700-377 while star tracker loss-of-lock
  24. Swift detection of a outburst from SAX J1810.8-2609
  25. GRB 070724B: Swift-XRT afterglow confirmation
  26. GRB070802: Swift/UVOT upper limits
  27. GRB 070802: Confirmation of the optical afterglow
  28. GRB 070802: Swift detection of a burst
  29. GRB 070724B: Swift-XRT afterglow likely candidate
  30. GRB 070724B: Suzaku WAM observation of the prompt emission
  31. GRB 070724B: Swift-XRT afterglow candidates
  32. GRB 070724b: First Gamma Ray Burst Localization by SuperAGILE onboard
  33. GRB 070721B: Swift detection of a burst
  34. GRB 070714: Swift detection of a bright burst, possibly short
  35. GRB070621: Swift XRT refined analysis
  36. GRB 070621: Gemini South optical imaging
  37. GRB 070621: Swift detection of a burst
  38. GRB 070616: Swift detection of a burst
  39. SWIFT J195509.6+261406 (GRB 070610): further observations
  40. GRB 070612B: KAIT limits
  41. GRB 070610: OPTIMA-Burst detection of continued strong flaring activity
  42. GRB 070611: VLT redshift
  43. Swift trigger 280447 is probably a Galactic transient
  44. GRB 070520B: Swift detection of a burst
  45. GRB 070520: Swift detection of a burst
  46. GRB 070508: Swift detection of an intense burst with an optical counterpart
  47. GRB070429B: VLT observations
  48. GRB 070429B: ROTSE-III Optical Limits
  49. GRB 070429B: Swift detection of a short burst
  50. GRB 070429: Swift detection of a burst
  51. GRB 070411: Late-time Keck imaging
  52. GRB 070411 : Planned XMM-Newton observation
  53. GRB 070411, deep LBT photometry
  54. GRB 070419A: RAPTOR Detection of Early Emission
  55. GRB 070419: Swift detection of a burst
  56. GRB 070318, SMARTS optical/IR afterglow observations
  57. GRB 070411: TLS data shows plateau, flares
  58. GRB 070411: Swift/UVOT observations
  59. GRB 070412: further NOT observations
  60. GRB 070411: Magellan/Clay photometry
  61. GRB 070411: Magellan/IMACS photometry
  62. GRB 070412: Nearby bright galaxy
  63. GRB 070411: Optical observations at Crni Vrh
  64. GRB 070411: Swift detection of a burst with optical afterglow
  65. GRB 070328: Swift detection of a burst
  66. Short-Hard GRB 070209: PROMPT Observations
  67. GRB 070318: Swift detection of a burst with an optical afterglow
  68. GRB 070306: IR observations and candidate afterglow
  69. GRB 070306: XRT Team Refined Analysis
  70. GRB070306 - SDSS Pre-burst Observations
  71. GRB 070227: optical observations
  72. GRB 070227: optical observations
  73. GRB070223: Swift burst
  74. GRB 070220: ART-3 Optical and NIR limits
  75. GRB 070220: Swift detection of a burst
  76. GRB 070208: MARGE Optical Observations
  77. GRB 070208: RAPTOR detection of early afterglow onset
  78. GRB 070208: MDM Optical Decay
  79. GRB 070208: Early IR detection and afterglow astrometry
  80. GRB 070208: Afterglow confirmation from P60
  81. GRB 070208: ROTSE-III Optical Limits
  82. GRB 070208: MDM Observations
  83. GRB 070208: Swift detection of a burst
  84. GRB 070125: optical observation
  85. GRB 070125: An IR Point Source and an Apparent Host Galaxy
  86. GRB 070129: Swift detection of a burst
  87. GRB 070125: further AAVSO optical observations
  88. GRB 070125: AAVSO optical observations
  89. GRB 070125: Continued P60 Observations
  90. GRB070125: Swift-XRT Refined Analysis
  91. GRB 070125: P60 Optical Afterglow Candidate
  92. GRB 070110: Swift detection of a burst with a possible optical afterglow
  93. GRB 061201: Nearby Galaxy Cluster Abell 995 is at z=0.0865
  94. Retractions of previous Swift-BAT triggers
  95. GRB 061210: Swift/XRT Astrometry Correction
  96. GRB 061222A: MITSuME Akeno optical upper limits
  97. GRB 061222B: Swift detection of a burst
  98. GRB 061201: Correction to GCN 5944
  99. GRB 061201: Magellan Redshift of nearby Abell cluster
  100. GRB 061210: MDM Follow-up Observation

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