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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"
  1. GRB071018: Correction to the title of the GCN 6936
  2. GRB 071018: Possible OT from Xinglong TNT observation
  3. GRB 071010B: Light Curve Break Confirmed
  4. GRB 071010A: Late-time Keck/LRIS photometry - possible host galaxy and jet break
  5. GRB 071018, Swift-BAT refined analysis
  6. GRB 071018?: Swift detection of a possible burst
  7. GRB 071010B: Suzaku WAM observation of the prompt emission
  8. GRB 071013: 3rd TLS Epoch - constraints on variability
  9. GRB 071013: TNT optical data refined analysis
  10. GRB 071010B: Keck/DEIMOS emission-line redshift
  11. GRB 071017: a SHORT GRB detected by INTEGRAL
  12. GRB 071013: TLS 2nd epoch - Kornienko candidate constant
  13. GRB071013: optical observations
  14. GRB 071010B: Optical observations of EST
  15. GRB 071010B: TLS 3rd Epoch - finally a break??
  16. GRB 071011: MITSuME Optical Observations
  17. GRB 070920A: deep optical observations at the NOT
  18. GRB 071010B: Photometry after 1.6 days
  19. GRB 071010B: Keck/LRIS Photometry
  20. GRB 071010B: TLS 2nd Epoch, refined analysis
  21. GRB 071013: TLS Upper Limit
  22. Correction to GCN circular no. # 6915 for GRB 071010B
  23. VLA detection of radio afterglow of GRB 071010B
  24. VLA non-detection of GRB 071011
  25. GRB 071013: Optical observations
  26. GRB 071013: optical observations at NOT
  27. GRB 071013, Swift-BAT refined analysis
  28. GRB071013: optical limit
  29. GRB071010B, BVRcIc field calibration
  30. GRB 20071013: Xinglong TNT optical Upper Limit
  31. GRB 071013: Swift detection of a burst
  32. GRB 071010C Swift-BAT detection of a burst
  33. GRB 071011: Optical Limit after 13.95hrs
  34. GRB 071011: Xinglong TNT Optical afterglow observations
  35. GRB 071010B correction to GCN 6892 optical observations
  36. GRB 071011: Swift-XRT refined analysis
  37. VLA non-detection of GRB 071010A
  38. GRB 071011: NAYUTA Optical Observation, correction to GCN6886
  39. GRB 071011, Optical afterglow
  40. GRB 071011: Confirmation of P60 optical afterglow
  41. GRB 071010B: Optical Detection
  42. GRB 071011: Kanazawa Optical limits
  43. GRB 071011: P60 Optical Afterglow Candidate
  44. GRB 071011: MARGE Optical Limits
  45. GRB 071010B: Super-LOTIS upper limit
  46. GRB 071010B optical photometry
  47. GRB 071011: XRT afterglow detection
  48. GRB 071010B: Keck/LRIS Spectroscopy
  49. GRB 071011, Swift-BAT refined analysis
  50. GRB 071010B: Gemini Spectroscopic Observations
  51. GRB 071011: Early Super-LOTIS Observations
  52. GRB 071011: NAYUTA Optical Observation
  53. GRB 071010A: Continued Keck Imaging
  54. GRB 071010B: Bright OT confirmed with TLS
  55. GRB 071011: Optical afterglow candidate
  56. GRB 071011: Swift detection of a burst
  57. Optical Observation: GRB 071010
  58. Optical observations: GRB 071010A
  59. Konus-Wind observation of GRB 071010B
  60. GRB071010B: Swift/XRT detection
  61. GRB 071010B, Swift-BAT refined analysis
  62. GRB 071010A: bright NIR afterglow
  63. GRB 071006, Swift-BAT refined analysis
  64. GRB071008: optical observations
  65. GRB 071010B possible optical transient
  66. GRB 071010A: Keck/LRIS Photometry
  67. GRB 071010B: Swift detection of a burst
  68. GRB 071010: Swift-XRT observation
  69. GRB 071008, Swift-BAT refined analysis
  70. GRB 071010, Swift-BAT refined analysis
  71. Konus-Wind observation of GRB 071006
  72. GRB071008: Swift-XRT observation
  73. GRB 071010 REM NIR observations
  74. GRB 071010: Keck/LRIS Spectroscopy
  75. GRB 071010: TAROT La Silla observatory photometry of the afterglow
  76. GRB 071010: Rapid PROMPT Detections
  77. GRB 071010: Keck Observations of the Afterglow
  78. GRB 071010: TAROT La Silla observatory detection of the afterglow
  79. GRB 071010: Swift detection of a burst
  80. GRB 071006 Swift-BAT detection of a burst
  81. GRB071008: IAC80 observation
  82. GRB 071008: Swift detection of a burst
  83. GRB 071003: XRT refined analysis
  84. GRB070920A: MAGIC telescope GeV observation
  85. Radio detection of GRB 071003 with the VLA
  86. GRB 070810B: further XRT analysis
  87. GRB 071003: VLT spectroscopy
  88. GRB 071003: Keck spectroscopy
  89. Konus-Wind observation of GRB 071003
  90. GRB071003: Faulkes Telescope North observations
  91. GRB 071003: Possible rebrightening
  92. GRB 071003 : Lulin R-band observations
  93. GRB 071003: Swift XRT position
  94. GRB 071003: OA power-law decay indices from KAIT
  95. GRB 071003: Keck HIRES spectroscopy
  96. GRB 071003, Swift-BAT refined analysis
  97. GRB 071003: MARGE Observations
  98. GRB 071003 Optical observations
  99. GRB 071003: P60 Confirmation of Optical Afterglow
  100. GRB 071003: KAIT optical afterglow observations

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