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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"

31730 results found.

  1. GRB 071101: TAROT Calern observatory optical observations
  2. GRB 071101: Swift XRT position
  3. GRB 071101: BOOTES-2 prompt optical observations
  4. GRB 071101: a nearby galaxy
  5. GRB 071031, Swift-BAT refined analysis
  6. GRB 071031: Swift/UVOT detection of afterglow
  7. GRB 071031: Swift-XRT Team refined analysis
  8. GRB 071020: MITSuME Akeno optical observations
  9. GRB 071031: REM NIR and Optical observation
  10. GRB 071031, SMARTS afterglow observations
  11. GRB 071031: VLT high-resolution spectroscopy
  12. GRB071031: Rapid PROMPT Detections
  13. GRB 071028B Swift-BAT detection of a burst
  14. GRB071025: Optical+NIR observations
  15. GRB 071028: SARA observations of variable source
  16. Swift UVOT upper limits to GRB071028
  17. GRB 071028: Swift-XRT Team refined analysis
  18. GRB 071028, Swift-BAT refined analysis
  19. GRB 071025: Kuiper Telescope Optical Observations
  20. GRB 071003: Infrared Photometry with Keck Adaptive Optics
  21. GRB 071018: Revised BAT position
  22. GRB 071025A: RAPTOR Observations of Complex Early Optical Behavior
  23. GRB071021: MARGE Optical Limits
  24. GRB071020, optical upper limit
  25. GRB 071025: SARA VRI upper limits
  26. GRB 071025 Milagro GeV/TeV Observations
  27. GRB071025: Optical Pre-imaging from Palomar
  28. Swift UVOT upper limits
  29. GRB071025: Xinglong TNT I-band upper limit
  30. GRB 071025: Swift-XRT Team refined analysis
  31. GRB 071025, Swift-BAT refined analysis
  32. GRB 071025: Early Super-LOTIS Observations
  33. GRB 071025: R/I-band update
  34. GRB071021 : CFHT Ks-band observation
  35. GRB 071025: ROTSE-III Refined Analysis
  36. GRB 071025: Swift XRT refined position
  37. GRB 071025a: PAIRITEL observations
  38. GRB071025: REM NIR afterglow
  39. GRB 071025: ROTSE-III Detection of Optical Counterpart
  40. GRB 071021: R-band detection and analysis
  41. GRB 071020: BTA spectroscopy
  42. GRB071021: Optical+NIR observations
  43. Possible radio detection of GRB 071021 with the VLA
  44. Optical observations of GRB 071020
  45. GRB 071021: (Relatively shallow) IR non-detections; motivation for optical spectroscopy
  46. GRB 071020: SARA observations
  47. Radio detection of GRB 071020 with the VLA
  48. GRB071010b: optical observation
  49. GRB 071021: Subaru NIR observation
  50. GRB 071021: Magellan i-band observation
  51. GRB 071021: Z-band detection
  52. GRB 071020: Fading slowly?
  53. GRB 071010B: Fading quickly
  54. GRB 071021: optical and NIR observations
  55. GRB 071021: possible high-z burst
  56. GRB 071021, Swift-BAT refined analysis
  57. GRB071018: 2nd epoch obsevations of Xinglong TNT
  58. GRB 071021: retraction of Faulkes Telescope South candidate
  59. GRB 071021: Swift-XRT Team refined analysis
  60. GRB 071021: Xinglong TNT optical Upper Limit
  61. GRB 071021 : Lulin R-band limit
  62. Konus-Wind observation of GRB 071020
  63. GRB 071021: Faulkes Telescope South optical candidate
  64. GRB 071010B: Independent Confirmation of Break
  65. GRB071020A: Xinglong TNT Optical afterglow observations
  66. GRB 071020: Swift-XRT refined analysis
  67. GRB 071020, Swift-BAT refined analysis
  68. GRB 071020A: IR Imaging with PAIRITEL
  69. GRB 071020: VLT spectroscopy
  70. GRB 071020: ROTSE-III Analysis of Optical Counterpart
  71. GRB 071020A: ROTSE-III Detection of Optical Counterpart
  72. Swift autonomous slewing re-enabled
  73. GRB071010b: optical observations
  74. GRB 071018: SARA observations
  75. GRB 071018: Swift-XRT observation
  76. GRB 071017 - Swift XRT observations
  77. VLA radio observation of GRB 071018
  78. GRB071018: Correction to the GCN 6936
  79. GRB071018: Correction to the GCN 6936
  80. GRB071018: Correction to the GCN 6936
  81. GRB071018: Correction to the title of the GCN 6936
  82. GRB 071018: Possible OT from Xinglong TNT observation
  83. GRB 071010B: Light Curve Break Confirmed
  84. GRB 071010A: Late-time Keck/LRIS photometry - possible host galaxy and jet break
  85. GRB 071018, Swift-BAT refined analysis
  86. GRB 071010B: Suzaku WAM observation of the prompt emission
  87. GRB 071013: 3rd TLS Epoch - constraints on variability
  88. GRB 071013: TNT optical data refined analysis
  89. GRB 071010B: Keck/DEIMOS emission-line redshift
  90. GRB 071013: TLS 2nd epoch - Kornienko candidate constant
  91. GRB071013: optical observations
  92. GRB 071010B: Optical observations of EST
  93. GRB 071010B: TLS 3rd Epoch - finally a break??
  94. GRB 071011: MITSuME Optical Observations
  95. GRB 070920A: deep optical observations at the NOT
  96. GRB 071010B: Photometry after 1.6 days
  97. GRB 071010B: Keck/LRIS Photometry
  98. GRB 071010B: TLS 2nd Epoch, refined analysis
  99. GRB 071013: TLS Upper Limit
  100. Correction to GCN circular no. # 6915 for GRB 071010B

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