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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"

25811 results found.

  1. GRB 071118, Swift-BAT refined analysis
  2. GRB 071117: TAROT La Silla observatory optical observations
  3. GRB 071118: Swift detection of a burst
  4. GRB 071117: Gemini Observations
  5. GRB 071117: Swift-XRT refined analysis
  6. GRB 071117, Swift-BAT refined analysis
  7. Swift detection of MXB 0656-072
  8. GRB 071112C: Optical and NIR data observed with KANATA
  9. GRB 071112C MITSuME Akeno early optical observation
  10. GRB 071112C: SARA upper limit
  11. GRB 071112C : Second Epoch Lulin R-band observations
  12. GRB071112C MITSuME Okayama Optical Observation
  13. GRB 071112C: Swift-BAT refined analysis
  14. GRB 071112C: Swift XRT refined analysis
  15. Swift UVOT upper limits of GRB071112B
  16. GRB 071112B: Gemini Optical Imaging
  17. GRB 071112B: Swift-XRT preliminary analysis
  18. GRB 071112B, Swift-BAT partial refined analysis of the SHB
  19. GRB 071112C : Lulin R-band observation
  20. GRB 071112C: TAROT Calern observatory optical observations
  21. Swift XRT follow-up observations of GRB071028B
  22. GRB071112C Xinglong_TNT_and_EST_afterglow observations
  23. GRB 071112C: Optical and NIR afterglows observed with KANATA
  24. GRB 071112C: Swift detection of a burst with an optical counterpart
  25. GRB 071112B: Swift detection of a short hard burst
  26. GRB 071112: Swift detection of a possible burst
  27. Swift/UVOT initial analysis of GRB071109
  28. GRB 071109: further Swift-XRT analysis
  29. GRB 071109: TAROT Calern observatory optical observations
  30. GRB 071109: Swift-XRT possible X-ray counterpart
  31. GRB 071109: IBIS refined analysis
  32. GRB 071104: Swift-XRT Team Refined Analysis
  33. GRB 071104: Possible Swift UVOT Afterglow Candidate
  34. GRB 071104: Swift-XRT position
  35. GRB 071104: Gamma Ray Burst Localization by SuperAGILE
  36. Swift XRT and UVOT observations of GRB071028B
  37. GRB 071101, Swift-BAT refined analysis
  38. GRB 071101: Swift-XRT Team refined analysis
  39. GRB071101: Optical and NIR upper limits by KANATA
  40. GRB0711101: Two new source from Xinglong TNT observation
  41. GRB 071101: TAROT Calern observatory optical observations
  42. GRB071101 LOAO B,V,R,I observation
  43. GRB 071101: Swift detection of a burst
  44. GRB 071031, Swift-BAT refined analysis
  45. GRB 071031: Swift-XRT Team refined analysis
  46. GRB 071020: MITSuME Akeno optical observations
  47. GRB 071031: REM NIR and Optical observation
  48. GRB 071031: Swift detection of a burst with an optical counterpart
  49. GRB 071028B Swift-BAT detection of a burst
  50. GRB 071028: SARA observations of variable source
  51. Swift UVOT upper limits to GRB071028
  52. GRB071028: Xinglong EST V-band upper limit
  53. GRB 071028: Swift-XRT Team refined analysis
  54. GRB 071028, Swift-BAT refined analysis
  55. GRB 071028: Swift detection of a burst
  56. GRB 071003: Infrared Photometry with Keck Adaptive Optics
  57. GRB071021: MARGE Optical Limits
  58. GRB071020, optical upper limit
  59. GRB 071025: SARA VRI upper limits
  60. Swift UVOT upper limits
  61. GRB071025: Xinglong TNT I-band upper limit
  62. GRB 071025: Swift-XRT Team refined analysis
  63. GRB 060602A: host redshift
  64. GRB 071025, Swift-BAT refined analysis
  65. GRB071021 : CFHT Ks-band observation
  66. GRB 071025: ROTSE-III Refined Analysis
  67. GRB 071025a: PAIRITEL observations
  68. GRB 071025: ROTSE-III Detection of Optical Counterpart
  69. GRB 071025: Swift detection of a burst
  70. GRB 071021: R-band detection and analysis
  71. Possible radio detection of GRB 071021 with the VLA
  72. GRB 071021: (Relatively shallow) IR non-detections; motivation for optical spectroscopy
  73. GRB 071020: SARA observations
  74. Radio detection of GRB 071020 with the VLA
  75. GRB071021: MITSuME Okayama Optical Upper Limits
  76. GRB 071021: Z-band detection
  77. GRB 071021: optical and NIR observations
  78. GRB 071021: possible high-z burst
  79. GRB 071021, Swift-BAT refined analysis
  80. GRB071018: 2nd epoch obsevations of Xinglong TNT
  81. GRB 071021: Swift-XRT Team refined analysis
  82. GRB 071021: Xinglong TNT optical Upper Limit
  83. GRB 071021 : Lulin R-band limit
  84. GRB 071021: Swift detection of a burst
  85. GRB071020A: Xinglong TNT Optical afterglow observations
  86. GRB 071020: Swift-XRT refined analysis
  87. GRB 071020, Swift-BAT refined analysis
  88. GRB 071020A: IR Imaging with PAIRITEL
  89. GRB 071020: ROTSE-III Analysis of Optical Counterpart
  90. GRB071020 - SDSS Pre-burst Observations
  91. GRB 071020: Swift detection of a bright burst
  92. GRB 071020A: ROTSE-III Detection of Optical Counterpart
  93. GRB 071018: Mercator Telescope optical observations
  94. Swift autonomous slewing re-enabled
  95. GRB 071018: SARA observations
  96. GRB 071018: Swift-XRT observation
  97. GRB 071017 - Swift XRT observations
  98. GRB 071018: Possible OT from Xinglong TNT observation
  99. GRB 071010B: Light Curve Break Confirmed
  100. GRB 071010A: Late-time Keck/LRIS photometry - possible host galaxy and jet break

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