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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"
  1. GRB 130102A: MASTER-Net optical observations
  2. GRB 130102A: Swift-XRT refined Analysis
  3. GRB 130102B: MAXI/GSC detection
  4. GRB 130102A: Enhanced Swift-XRT position
  5. GRB 130102A: IAC80 I-band observations
  6. GRB 130102A: Swift detection of a burst
  7. GRB 121226A: 5.8 GHz VLA observations
  8. Swift Trigger 544381 is a noise event
  9. GRB 121229A: Swift-XRT refined Analysis
  10. GRB 121229A, Swift-BAT refined analysis
  11. GRB 121229A: Swift/UVOT Upper Limits
  12. GRB 121229A: Enhanced Swift-XRT position
  13. GRB 121229A: VLT/X-shooter redshift
  14. Swift Trigger 544381 is unlikely to be a GRB
  15. GRB 121229A: MAXI/GSC detection
  16. GRB 121229A: GROND detection of the afterglow
  17. Skynet/PROMPT observations of GRB121229a
  18. GRB 121229A: Swift detection of a burst
  19. GRB 121226A: 10.4m GTC optical observations
  20. GRB 121226A: Swift/UVOT Upper Limits
  21. GRB 121226A: Swift-XRT refined Analysis
  22. GRB 121226A, Swift-BAT refined analysis
  23. GRB 121226A: NOT optical upper limit
  24. GRB 121226A: Optical Observations
  25. GRB 121226A: MITSuME Okayama Optical upper limits
  26. GRB 121226A: Zadko observatory - Gingin optical observations
  27. GRB 121226A: BOOTES-4/MET optical observations
  28. GRB 121226A: Swift detection of a burst
  29. Konus-Wind observation of GRB 121225B
  30. IPN Triangulation of GRB 121225B
  31. GRB 121225B: Fermi GBM observation
  32. GRB 121225B: Fermi LAT Detection
  33. GRB 121225A: MAXI/GSC detection
  34. Swift-BAT refined analysis of SGR 1E 1841-045 (Trigger=543763)
  35. Trigger 543763: SGR 1E 1841-045: Swift detection of a soft gamma repeater burst (aka Kes 73)
  36. GRB 121217A: ATCA 44GHz upper limit
  37. GRB 121217A: Swift-BAT refined analysis
  38. GRB 121217A theoretical estimate of redshift and of supernova occurrence
  39. GRB 121217A: Fermi GBM observation
  40. GRB 121217A: Swift-XRT refined Analysis
  41. GRB 121217A: Swift/UVOT Detection
  42. GRB 121217A: GROND Detection of the Afterglow
  43. GRB 121217A: Enhanced Swift-XRT position
  44. GRB 121217A: Swift detection of a burst
  45. GRB 121123A: NIKA (New IRAM KID Arrays) millimetre observations at the 30-m Pico Veleta telescope
  46. Subject : GRB 121209A: LOAO Observation
  47. GRB 121209A: Swift/UVOT Upper Limits
  48. GRB 121212A: LOAO IzY Observation
  49. GRB 121209A: MAXI/GSC detection
  50. GRB 121212A: PdBI mm observations
  51. GRB121212A: NOT optical imaging
  52. GRB 121209A: Early CARMA Observations
  53. GRB 121211A: Continued RATIR Optical and NIR Observations, Fading
  54. GRB 121212A: Maidanak optical observations
  55. GRB 121211A: Fermi GBM observation
  56. GRB 121211A: RATIR Optical and NIR Observations
  57. GRB 121212A: RAPTOR Limits During Gamma-Ray Emitting Interval
  58. GRB 121211A: RAPTOR Limits During Gamma-Ray Emitting Interval
  59. GRB 121212A: PAIRITEL NIR Observations
  60. GRB 121212A: Swift-XRT refined Analysis
  61. GRB 121212A: P60 Observations
  62. GRB 121212A: optical observations in ISON-NM observatory
  63. GRB 121212A: Keck observations
  64. GRB121212A: Swift/UVOT Detection
  65. GRB 121212A: Swift-BAT refined analysis
  66. GRB 121211A: Swift-BAT refined analysis
  67. GRB 121212A: Enhanced Swift-XRT position
  68. GRB 121212A: A long GRB detected by INTEGRAL
  69. GRB 121212A: Swift detection of a burst
  70. GRB 121211A: Swift/UVOT Detection
  71. GRB 121211A: MITSuME Okayama Optical Observation
  72. GRB 121211A: Swift-XRT refined Analysis
  73. GRB 121211A: Enhanced Swift-XRT position
  74. GRB 121211A: Keck/LRIS redshift
  75. GRB 121211A - Faulkes Telescope North afterglow confirmation
  76. GRB 121211A: Swift detection of a burst with an optical counterpart
  77. GRB 121209A: Keck observations
  78. GRB 121209A: CARMA 3mm Observations
  79. GRB 121209A: EVLA Observations
  80. GRB 121209A: Swift-XRT refined Analysis
  81. GRB 121209A: Swift-BAT refined analysis
  82. GRB 121209A: Enhanced Swift-XRT position
  83. GRB121209A: RATIR Optical and NIR Upper Limits
  84. GRB 121209A: GROND optical afterglow candidate
  85. GRB 121209A: Gemini-South imaging
  86. GRB 121209A: PAIRITEL NIR Observations
  87. GRB 121209A: UVOT Observation
  88. GRB 121209A: Swift detection of a burst
  89. GRB 121127A: Suzaku WAM observation of the prompt emission
  90. GRB 121128A: Optical Observations
  91. GRB 121122A: Suzaku WAM observation of the prompt emission
  92. GRB 121202A: Swift/UVOT Upper Limits
  93. GRB 121202A: Swift-XRT refined Analysis
  94. GRB 121202A: Fermi GBM observation
  95. GRB 121202A: Enhanced Swift-XRT position
  96. GRB 121202A: Swift-BAT refined analysis
  97. GRB 121202A: Swift-XRT observations
  98. GRB 121201A: X-shooter redshift
  99. GRB121202A: Swift/UVOT Observations
  100. GRB 121202A: TAROT Calern observatory optical observations

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