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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.

Advanced Search Examples (click to copy):

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

42884 results found.

  1. GRB 060421: TTT Observations
  2. OT 060420: Likely Not a New Cosmic Transient
  3. No OT 060420 in MASCOT images
  4. Swift-BAT detection of Mrk 421
  5. OT 060420: CONCAM detection of a candidate new magnitude 5 optical
  6. GRB060421: Swift/UVOT observations
  7. GRB 060421: Swift-BAT Refined Analysis
  8. GRB 060421: Swift-XRT refined analysis
  9. GRB 060418: prediction of t_break
  10. GRB060418: optical observations
  11. Konus-Wind observation of GRB 060418
  12. Possible GRB060421: BART limits
  13. GRB(?) 060421: Swift detection of a burst
  14. GRB 060418: JHKs PAIRITEL Observations of Afterglow
  15. GRB 060418: Radio Observations
  16. GRB060418, BVRcIc field calibration
  17. GRB060418: Optical Observations
  18. GRB 060418: FRAM early afterglow observation
  19. VLT/UVES observations of GRB060418
  20. GRB060418: Swift XRT Team Refined Analysis
  21. GRB 060418, SMARTS continuing afterglow observations
  22. GRB 060418: PROMPT Detections
  23. GRB 060418, SMARTS optical/IR afterglow observations
  24. GRB060418: Magellan/MIKE Spectroscopic Redshift
  25. GRB060418 : LT optical afterglow observation
  26. GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
  27. SGR 1900+14: Refined analysis of the Swift-BAT outburst
  28. GRB 060413: REM NIR Observations
  29. SGR 1900+14: Swift detection of an outburst
  30. GRB 060413: Watcher UBVR observations
  31. GRB 060413: XRT refined analysis
  32. GRB 060413: No Optical Afterglow in Swift/UVOT TDRSS Data
  33. GRB 060413: Swift detection of a burst
  34. GRB060403: optical observations
  35. GRB 060403 Optical observations
  36. GRB 060403: MITSuME optical observation
  37. GRB060403: Optical Limit
  38. GRB060403: XRT refined analysis
  39. GRB 060403: Swift/UVOT upper limits
  40. HETE Triggers H4043 and H4044 Not Due to New Cosmic Source
  41. SGR 1900+14: BAT observations
  42. GRB 060403: Refined analysis of the Swift-BAT burst
  43. Konus-Wind observation of the recent SGR 1900+14 activity. Will
  44. GRB 060403: Swift detection of a burst
  45. GRB060331: Swift/UVOT upper limits
  46. H4044, a Repeat Outburst From The Source of H4043 (="GRB060331")
  47. Swift XRT observations of the HETE transient H4043
  48. HETE Trigger 4043: ROTSE-III Optical Limits
  49. H4043, an unusual high-energy transient observed by HETE
  50. GRB 060322: LNA optical limit
  51. SGR 1900+14: bright burst detected by Konus-Wind on March 28
  52. INTEGRAL and XMM ToO observations of SGR1900+14
  53. SGR 1900+14: Swift-BAT detection of a cluster of outbursts
  54. SGR 1900+14: Swift-BAT detection of a bright outburst
  55. GRB 060218SN 2006aj: optical observations at Rozhen Observatory
  56. GRB 060323 : WIDGET simultaneous optical observations
  57. GRB 060323: Early optical observation at Xinglong
  58. GRB060218, optical observations
  59. GRB 060322: Confirmation of Swift XRT afterglow
  60. GRB 060211A: optical observation
  61. GRB060323: optical limit
  62. GRB060211B: optical observation
  63. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  64. SGR 1900+14: Swift detection of renewed activity
  65. GRB060323: NOT optical observations
  66. GRB 060322: IAC80 optical observations
  67. GRB 060322: Swift XRT afterglow candidate
  68. GRB060323: P60 Observations
  69. GRB 060323: Swift/UVOT Observations
  70. GRB 060323: optical afterglow confirmed
  71. GRB060323: NOT observations
  72. GRB 060323: Tautenburg OT candidate retraction
  73. GRB 060323: Refined analysis of the Swift-BAT burst
  74. GRB 060323: optical observations at TNG
  75. GRB 060323: Swift XRT refined analysis
  76. GRB 060323: BVRI observations at Tautenburg, aftreglow candidate
  77. GRB 060323: Swift/XRT position
  78. GRB 060322: Refined analysis of the Swift-BAT burst
  79. GRB060323 - SDSS Pre-Burst Observations
  80. GRB 060323: Swift detection of a burst with a possible optical afterglow
  81. GRB 060322: Swift-BAT detection of a 200-sec burst
  82. GRB060219: optical observation
  83. GRB060206: optical observation
  84. GRB060218/SN2006aj: optical observations
  85. GRB 060218/SN 2006aj, LNA optical observation
  86. GRB060218: Refined photometric calibration of comparison stars
  87. GRB 060319: WHT K-band candidate afterglow
  88. GRB 060319: IAC-80 optical observations
  89. GRB060319: Swift XRT refined analysis
  90. GRB060319: MASTER limit
  91. GRB 060319: Swift-BAT refined analysis
  92. GRB060319 : Liverpool Telescope optical limit
  93. GRB060319: MASTER optical observation
  94. GRB060319 - SDSS Pre-burst Observations
  95. GRB060319: Swift/XRT position
  96. GRB 060319: Swift detection of a burst
  97. GRB060313: Radio Observations
  98. GRB 060313: early afterglow NIR upper limits with REM
  99. IBAS Alert n. 3221: not a GRB
  100. Konus-Wind observation of GRB 060313

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