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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"

24405 results found.

  1. GRB 060421: TTT Observations
  2. OT 060420: Likely Not a New Cosmic Transient
  3. Swift-BAT detection of Mrk 421
  4. OT 060420: CONCAM detection of a candidate new magnitude 5 optical
  5. GRB 060421: Swift-BAT Refined Analysis
  6. GRB 060421: Swift-XRT refined analysis
  7. Konus-Wind observation of GRB 060418
  8. GRB(?)060421:MASTER optical limit
  9. Possible GRB060421: BART limits
  10. GRB 060418: FRAM early afterglow observation
  11. GRB 060418: Refined Analysis of the Swift-BAT burst
  12. GRB060418: Swift XRT Team Refined Analysis
  13. GRB 060418, SMARTS continuing afterglow observations
  14. GRB 060418: PROMPT Detections
  15. GRB 060418, SMARTS optical/IR afterglow observations
  16. GRB 060413: Refined analysis of the Swift-BAT burst
  17. GRB 060413: XRT refined analysis
  18. GRB 060413: Swift detection of a burst
  19. GRB060403: optical observations
  20. GRB 060403: Swift/UVOT upper limits
  21. SGR 1900+14: BAT observations
  22. GRB 060403: Refined analysis of the Swift-BAT burst
  23. Konus-Wind observation of the recent SGR 1900+14 activity. Will
  24. GRB060331: Swift/UVOT upper limits
  25. HETE Trigger 4043: ROTSE-III Optical Limits
  26. H4043, an unusual high-energy transient observed by HETE
  27. SGR 1900+14: bright burst detected by Konus-Wind on March 28
  28. GRB 060322: Confirmation of Swift XRT afterglow
  29. GRB 060211A: optical observation
  30. GRB060323: optical limit
  31. GRB060211B: optical observation
  32. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  33. GRB 060322: Swift XRT afterglow candidate
  34. GRB 060323: optical afterglow confirmed
  35. GRB 060323: Refined analysis of the Swift-BAT burst
  36. GRB 060323: optical observations at TNG
  37. GRB 060323: Swift XRT refined analysis
  38. GRB 060322: Refined analysis of the Swift-BAT burst
  39. GRB060219: optical observation
  40. GRB060206: optical observation
  41. GRB060218/SN2006aj: optical observations
  42. GRB 060319: IAC-80 optical observations
  43. GRB060319: Swift XRT refined analysis
  44. GRB060319: MASTER limit
  45. GRB 060319: Swift-BAT refined analysis
  46. GRB060319: MASTER optical observation
  47. GRB 060313: early afterglow NIR upper limits with REM
  48. IBAS Alert n. 3221: not a GRB
  49. Konus-Wind observation of GRB 060313
  50. GRB 060313: PROMPT Observations
  51. GRB060313: optical observations of the afterglow candidate
  52. GRB 060313: Refined analysis of the Swift-BAT bright short hard burst
  53. GRB060218: SARA Observations of SN2006aj
  54. GRB 060312: Refined analysis of the Swift-BAT burst
  55. GRB 060218/SN 2006aj, high resolution spectra
  56. GRB 060312: ROTSE-III Optical Limits
  57. IBAS Alert n. 3218 : not a real GRB
  58. GRB 060306: SOAR Ks Observations
  59. Bright short hard GRB 060303: IPN localization and Konus spectrum
  60. GRB060219: Liverpool Telescope observations
  61. GRB 060306: MAGNUM observations
  62. GRB060218: analysis of the XMM-Newton observation
  63. GRB 060306: Swift-BAT refined analysis
  64. GRB 060306: Swift-XRT team refined analysis
  65. GRB 060306: PROMPT Observations
  66. GRB 060218: RTT150 optical observations
  67. GRB060223b: optical limit
  68. GRB060218/SN 2006aj: optical observation in V
  69. GRB060218/SN 2006aj: optical observation
  70. GRB 060121: HST observations
  71. GRB 060223b: Swift/UVOT Upper Limits
  72. GRB 060218/SN 2006aj, SMARTS optical/IR observations
  73. GRB 060218 : Radio upper limits from GMRT
  74. GRB 060223B: Swift-BAT refined analysis
  75. GRB 060218/SN 2006aj: Swift-BAT fluence and peak flux
  76. GRB 060223: Swift-BAT refined analysis
  77. Correction to GCN 4816 on GRB060218
  78. GRB 060219: Swift-BAT refined analysis
  79. GRB 060218: Likely an underluminous GRB
  80. GRB 051221B: Swift-XRT Team Refined Analysis
  81. GRB060218: Swift/XRT Team preliminary analysis of the possible burst
  82. GRB 060218A: ROTSE-III Possible Optical Flare
  83. Preliminary refined analysis of the Swift-BAT trigger 191157
  84. GRB 060211B: Skynet Observations
  85. GRB060213: Swift XRT observations and possible afterglow candidate
  86. GRB060213: MASTER final result
  87. GRB060213:_MASTER_optical_observation
  88. Konus-Wind observation of bright hard GRB 060213
  89. GRB 060213: IPN localization
  90. GRB 060211A: Further refined analysis of the Swift burst
  91. GRB060121: optical observations
  92. GRB060110: optical observations
  93. GRB060105: optical observations
  94. GRB 060211A: Partial refined analysis on the Swift-BAT burst
  95. GRB 060206: SOAR Detections
  96. GRB 050826: Optical Afterglow and Host Galaxy
  97. GRB 060210: Further refined analysis of the Swift-BAT burst
  98. GRB 060211B: Swift/BAT refined analysis
  99. GRB 060211B: Swift-XRT Team refined analysis
  100. GRB060211.7: MASTER_optical_observation under the snow

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