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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"

21451 results found.

  1. GRB 071028: Swift detection of a burst
  2. GRB 071025: Kuiper Telescope Optical Observations
  3. GRB 071018: Revised BAT position
  4. GRB 071025A: RAPTOR Observations of Complex Early Optical Behavior
  5. GRB071021: MARGE Optical Limits
  6. GRB071020, optical upper limit
  7. GRB 071025 Milagro GeV/TeV Observations
  8. Swift UVOT upper limits
  9. GRB071025: Xinglong TNT I-band upper limit
  10. GRB 071025: Swift-XRT Team refined analysis
  11. GRB 071025, Swift-BAT refined analysis
  12. GRB 071025: Early Super-LOTIS Observations
  13. GRB 071025: ROTSE-III Refined Analysis
  14. GRB 071025: Swift XRT refined position
  15. GRB071025: REM NIR afterglow
  16. GRB 071025: ROTSE-III Detection of Optical Counterpart
  17. GRB 071025: Swift detection of a burst
  18. GRB 071020: BTA spectroscopy
  19. Possible radio detection of GRB 071021 with the VLA
  20. Radio detection of GRB 071020 with the VLA
  21. GRB 071021: Subaru NIR observation
  22. GRB071021: MITSuME Okayama Optical Upper Limits
  23. GRB 071021: Magellan i-band observation
  24. GRB 071021: Magellan R-band observation
  25. GRB 071021: optical and NIR observations
  26. GRB 071021, Swift-BAT refined analysis
  27. GRB071018: 2nd epoch obsevations of Xinglong TNT
  28. GRB 071021: Swift-XRT Team refined analysis
  29. GRB 071021: Xinglong TNT optical Upper Limit
  30. GRB 071021 : Lulin R-band limit
  31. Konus-Wind observation of GRB 071020
  32. GRB 071021: Faulkes Telescope South optical candidate
  33. GRB 071021: Swift detection of a burst
  34. GRB 071020: Swift-XRT refined analysis
  35. GRB 071020, Swift-BAT refined analysis
  36. GRB 071020: ROTSE-III Analysis of Optical Counterpart
  37. GRB071020 - SDSS Pre-burst Observations
  38. GRB 071020: Swift detection of a bright burst
  39. GRB 071020A: ROTSE-III Detection of Optical Counterpart
  40. GRB 071018: Mercator Telescope optical observations
  41. Swift autonomous slewing re-enabled
  42. GRB 071018: SARA observations
  43. GRB 071018: Swift-XRT observation
  44. GRB 071017 - Swift XRT observations
  45. VLA radio observation of GRB 071018
  46. GRB 071010A: Late-time Keck/LRIS photometry - possible host galaxy and jet break
  47. GRB 071018, Swift-BAT refined analysis
  48. GRB 071018?: Swift detection of a possible burst
  49. GRB 071010B: Suzaku WAM observation of the prompt emission
  50. GRB 071013: 3rd TLS Epoch - constraints on variability
  51. GRB 071013: TLS Upper Limit
  52. VLA detection of radio afterglow of GRB 071010B
  53. VLA non-detection of GRB 071011
  54. GRB 071013: Optical observations
  55. GRB 071013, Swift-BAT refined analysis
  56. GRB 071013: Swift detection of a burst
  57. GRB 071010C Swift-BAT detection of a burst
  58. GRB 071011: Swift-XRT refined analysis
  59. VLA non-detection of GRB 071010A
  60. GRB 071011, Optical afterglow
  61. GRB 071011: Confirmation of P60 optical afterglow
  62. GRB 071011: Kanazawa Optical limits
  63. GRB 071011: P60 Optical Afterglow Candidate
  64. GRB 071011: MARGE Optical Limits
  65. GRB 071011: XRT afterglow detection
  66. GRB 071011, Swift-BAT refined analysis
  67. GRB 071011: Early Super-LOTIS Observations
  68. GRB 071010B: Bright OT confirmed with TLS
  69. GRB 071011: Swift detection of a burst
  70. Optical Observation: GRB 071010
  71. Optical observations: GRB 071010A
  72. Konus-Wind observation of GRB 071010B
  73. GRB071010B: Swift/XRT detection
  74. GRB 071010B, Swift-BAT refined analysis
  75. GRB 071006, Swift-BAT refined analysis
  76. GRB071008: optical observations
  77. GRB 071010B: Swift detection of a burst
  78. GRB 071010: Swift-XRT observation
  79. GRB 071008, Swift-BAT refined analysis
  80. GRB 071010, Swift-BAT refined analysis
  81. GRB071008: Swift-XRT observation
  82. GRB 071010: TAROT La Silla observatory detection of the afterglow
  83. GRB 071010: Swift detection of a burst
  84. GRB 071006 Swift-BAT detection of a burst
  85. GRB071008: IAC80 observation
  86. GRB 071008: Swift detection of a burst
  87. GRB 071003: XRT refined analysis
  88. GRB070920A: MAGIC telescope GeV observation
  89. Radio detection of GRB 071003 with the VLA
  90. GRB 070810B: further XRT analysis
  91. Konus-Wind observation of GRB 071003
  92. GRB 071003: Swift XRT position
  93. GRB 071003, Swift-BAT refined analysis
  94. GRB 071003: MARGE Observations
  95. GRB 071003 Optical observations
  96. GRB 071003: KAIT optical afterglow observations
  97. GRB 071003: Swift detection of a bright burst
  98. GRB 070714B: host galaxy spectroscopic redshift
  99. GRB 071001: Swift-XRT Team refined analysis
  100. GRB 071001, Swift-BAT refined analysis

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