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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. GRB 120308A: Enhanced Swift-XRT position
  2. GRB 120308A: Swift-BAT refined analysis
  3. GRB 120308A: IAC80 I-band observations
  4. GRB 120308A: PAIRITEL NIR observations
  5. GRB 120308A: confirmation of the optical afterglow
  6. GRB 120308A: Liverpool Telescope optical afterglow candidate
  7. GRB 120308A: Swift detection of a burst
  8. GRB 120305A: D50 optical limits
  9. GRB 120305A: Swift spectral lag analysis
  10. GRB 120302A, the review of the sky area in plate archives
  11. GRB 120302A: Fermi GBM Observation
  12. GRB 120302A: Swift-BAT refined position and a possible XRT and UVOT counterpart
  13. GRB 120305A: Swift/UVOT Upper Limits
  14. GRB 120305A: EVLA deep limit on a radio counterpart
  15. GRB 120305A: Swift-XRT refined Analysis
  16. GRB 120305A: Enhanced Swift-XRT position
  17. GRB 120305A: Swift-BAT refined analysis
  18. GRB 120305A - Liverpool Telescope Observations
  19. GRB 120305A: MASTER-NET early optical observations
  20. GRB 120305A: Swift detection of a short burst
  21. GRB 120302A: GROND detection of an afterglow candidate
  22. GRB 120302A, Swift-BAT refined analysis
  23. GRB 111222A: Swift observation on 2012 February 06/07
  24. GRB 120302A found in ground analysis of BAT data
  25. GRB 120229A: Spectral lag analysis
  26. GRB 120229A, Swift-BAT refined analysis
  27. GRB 120229A: Swift detection of a short burst
  28. Konus-Wind observation of GRB 120226A
  29. GRB 120226A: Fermi-GBM and Fermi-LAT detections; LAT position retraction
  30. GRB 120226A: Fermi-LAT data analysis
  31. IPN Triangulation of GRB 120226A
  32. GRB 120227A: RAPTOR Limit During the Gamma-Ray Emitting Interval
  33. GRB 120224A: VLT/X-shooter observations
  34. GRB 120224A: optical observation in Mondy observatory
  35. GRB 120226A: Fermi-LAT detection of a burst
  36. GRB 120224A: GROND detection of the afterglow candidate
  37. GRB 120219A, the review of the sky area in plate archives
  38. GRB 120224A: Swift-XRT refined Analysis
  39. Swift Trigger 516027 is CC Eri
  40. GRB 120224A: Swift/UVOT Upper Limits
  41. GRB 120224A: Swift-BAT refined analysis
  42. GRB 120224A: FTN optical observations
  43. GRB 120224A: Enhanced Swift-XRT position
  44. GRB 120224A: Swift detection of a burst
  45. GRB_120215, the_review_of_the_sky_area_in_plate_archives
  46. GRB 1202019A: optical observation in Mondy observatory
  47. GRB 120219A: MASTER prompt and early optical limit and OT discussion
  48. GRB 120219A: 1.23m CAHA optical observations
  49. GCN 12974 : Errata in the Subject
  50. GRB 120219A, optical observations
  51. GRB120219A: Keck Observations
  52. GRB 120215A: MITSuME Akeno Optical upper limits
  53. GRB 120219A: Swift-XRT refined Analysis
  54. GRB 120219A: Swift/UVOT Upper Limits
  55. GRB 120219A: MITSuME Okayama Optical upper limits
  56. GRB 120219A: Swift-BAT refined analysis
  57. GRB 120219A: Enhanced Swift-XRT position
  58. GRB120219A: TNT optical afterglow candidates
  59. GRB 120219A: MASTER-NET prompt and early optical observations
  60. GRB 120219A: Swift detection of a burst
  61. GRB 120218A: Swift-BAT refined analysis
  62. GRB 120218A: Swift detection of a burst
  63. GRB 120215A: Swift/UVOT Upper Limits
  64. GRB 120215A: MITSuME Okayama Optical upper limits
  65. GRB 120215A: Swift-XRT refined Analysis
  66. Fermi GBM detection of an SGR-like burst
  67. GRB 120215A: Enhanced Swift-XRT position
  68. Skynet/PROMPT observations of GRB120215A
  69. GRB 120215A: Swift-BAT refined analysis
  70. GRB 120215A: Swift detection of a burst
  71. GRB 120211A : LOAO optical observations
  72. GRB 120213A: Swift-XRT refined Analysis
  73. GRB 120213A: Swift/UVOT Upper Limits
  74. GRB 120212A: Fermi GBM observation
  75. GRB 120212A: GMG optical observation
  76. GRB 120213A: Enhanced Swift-XRT position
  77. GRB 120212A: MITSuME Ishigakijima Optical Observation
  78. GRB 120213A: Swift-BAT refined analysis
  79. GRB 120213A: MASTER-NET early optical observations
  80. GRB 120213A: Prompt enhanced Swift-XRT position
  81. GRB 120212A: Swift-XRT refined Analysis
  82. GRB 120213A: Swift detection of a burst
  83. GRB 120212A: NOT optical observation
  84. GRB 120212A: Swift/UVOT Detection
  85. GRB 120212A: Swift-BAT refined analysis
  86. GRB 120212A: Errata of subject in GCNC 12936
  87. GRB 120212A: Enhanced Swift-XRT position
  88. GRB 120211A: MITSuME Okayama Ks-band Observation
  89. GRB 120212A: Kanata/HOWPol optical observation
  90. GRB 120212A: Swift-XRT observations
  91. GRB 120212A: Swift/UVOT detection
  92. GRB 120212A: Faulkes Telescope South afterglow candidate
  93. GRB 120211A: GROND Upper limits
  94. GRB 120212A: Swift detection of a burst
  95. GRB 120211A: MITSuME Okayama and Ishigakijima Optical upper limits
  96. GRB 120211A, optical observations
  97. GRB 120211A: Swift-XRT refined Analysis
  98. GRB 120211A: Swift/UVOT Upper Limits
  99. GRB 120211A: MASTER early optical observations
  100. GRB 120211A: Swift-BAT refined analysis

Advanced

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