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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"

32494 results found.

  1. GRB 060413: Refined analysis of the Swift-BAT burst
  2. GRB 060413: Watcher UBVR observations
  3. GRB 060413: XRT refined analysis
  4. GRB 060413: No Optical Afterglow in Swift/UVOT TDRSS Data
  5. GRB 060413: Swift detection of a burst
  6. GRB060403: optical observations
  7. GRB 060403 Optical observations
  8. GRB 060403: MITSuME optical observation
  9. GRB060403: Optical Limit
  10. GRB060403: XRT refined analysis
  11. GRB 060403: Swift/UVOT upper limits
  12. SGR 1900+14: BAT observations
  13. GRB 060403: Refined analysis of the Swift-BAT burst
  14. GRB060403: Swift XRT refined position
  15. Konus-Wind observation of the recent SGR 1900+14 activity. Will
  16. HETE trigger H4044: RTT150 optical observations
  17. GRB060331: Swift/UVOT upper limits
  18. H4044, a Repeat Outburst From The Source of H4043 (="GRB060331")
  19. Swift XRT observations of the HETE transient H4043
  20. HETE Trigger 4043: ROTSE-III Optical Limits
  21. H4043, an unusual high-energy transient observed by HETE
  22. GRB 060322: LNA optical limit
  23. SGR 1900+14: bright burst detected by Konus-Wind on March 28
  24. INTEGRAL and XMM ToO observations of SGR1900+14
  25. GRB 060218SN 2006aj: optical observations at Rozhen Observatory
  26. GRB 060323 : WIDGET simultaneous optical observations
  27. GRB 060323: Early optical observation at Xinglong
  28. GRB060218, optical observations
  29. GRB 060322: Confirmation of Swift XRT afterglow
  30. GRB 060211A: optical observation
  31. GRB060323: optical limit
  32. GRB060211B: optical observation
  33. SGR 1900+14: CORRECTION to GCN 4923
  34. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  35. GRB060323: NOT optical observations
  36. GRB 060322: Swift XRT afterglow candidate
  37. GRB060323: P60 Observations
  38. GRB 060323: Swift/UVOT Observations
  39. GRB 060323: optical afterglow confirmed
  40. GRB060323: NOT observations
  41. GRB 060323: Optical Observations
  42. GRB 060323: Tautenburg OT candidate retraction
  43. GRB 060323: Refined analysis of the Swift-BAT burst
  44. GRB 060323: optical observations at TNG
  45. GRB 060323: Swift XRT refined analysis
  46. GRB 060323: BVRI observations at Tautenburg, aftreglow candidate
  47. GRB 060323: Swift/XRT position
  48. GRB 060322: Refined analysis of the Swift-BAT burst
  49. GRB060323, optical observation
  50. GRB060206: optical observation
  51. GRB060218/SN2006aj: optical observations
  52. GRB 060218/SN 2006aj, LNA optical observation
  53. GRB060218: Refined photometric calibration of comparison stars
  54. GRB 060319: WHT K-band candidate afterglow
  55. GRB060319: Swift XRT refined analysis
  56. GRB060319: Swift/UVOT upper limits
  57. GRB 060319: Re-analysis of TNG data
  58. GRB060319: MASTER limit
  59. GRB 060319: Swift-BAT refined analysis
  60. GRB 060319 optical observations at TNG
  61. GRB060319 : Liverpool Telescope optical limit
  62. GRB060319 - SDSS Pre-burst Observations
  63. GRB060319: Swift/XRT position
  64. GRB060313: Radio Observations
  65. GRB 060313: early afterglow NIR upper limits with REM
  66. Konus-Wind observation of GRB 060313
  67. GRB060313: SSO 40inch Observations
  68. GRB 060313: Further analysis of the Swift-BAT bright short hard burst
  69. GRB 060313: PROMPT Observations
  70. GRB 060313: Swift/UVOT Observations
  71. GRB060313:Gemini South Observations
  72. GRB 060313: Swift-XRT team refined analysis
  73. GRB060313: optical observations of the afterglow candidate
  74. GRB 060313: Refined analysis of the Swift-BAT bright short hard burst
  75. GRB 060313, SMARTS optical counterpart?
  76. GRB 060313: Possible optical counterpart
  77. GRB 060313: Swift XRT position
  78. GRB 060313, SMARTS optical/IR observations
  79. GRB060313: optical and near infrared observations with REM
  80. GRB060218: SARA Observations of SN2006aj
  81. GRB 060312: Refined analysis of the Swift-BAT burst
  82. GRB 060312: Swift XRT team refined analysis
  83. GRB060306: APO Ks-band Imaging Observations
  84. GRB 060312: ROTSE-III Optical Limits
  85. GRB 060306: SOAR Ks Observations
  86. GRB 060306: MAGNUM observations
  87. Swift/UVOT observations of GRB060306
  88. GRB 060306: Swift-BAT refined analysis
  89. GRB 060306: Swift-XRT team refined analysis
  90. GRB 060306: PROMPT Observations
  91. GRB 060218: RTT150 optical observations
  92. GRB060218: Ep,i - Eiso correlation
  93. GRB060223b: optical limit
  94. GRB060218/SN 2006aj: optical observation in V
  95. GRB060218/SN 2006aj: optical observation
  96. GRB 060121: HST observations
  97. GRB 060218 : GMRT observation [Correction and Improvement]
  98. GRB 060223b: Swift/UVOT Upper Limits
  99. GRB 060218/SN 2006aj, SMARTS optical/IR observations
  100. GRB 060223B: Swift XRT possible afterglow

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