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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"

32509 results found.

  1. GRB 071025A: RAPTOR Observations of Complex Early Optical Behavior
  2. GRB071021: MARGE Optical Limits
  3. GRB071020, optical upper limit
  4. GRB 071025: SARA VRI upper limits
  5. GRB 071025 Milagro GeV/TeV Observations
  6. GRB071025: Optical Pre-imaging from Palomar
  7. Swift UVOT upper limits
  8. GRB071025: Xinglong TNT I-band upper limit
  9. GRB 071025: Swift-XRT Team refined analysis
  10. GRB 071025, Swift-BAT refined analysis
  11. GRB 071025: Early Super-LOTIS Observations
  12. GRB 071025: R/I-band update
  13. GRB071021 : CFHT Ks-band observation
  14. GRB 071025: ROTSE-III Refined Analysis
  15. GRB 071025: Swift XRT refined position
  16. GRB 071025a: PAIRITEL observations
  17. GRB071025: REM NIR afterglow
  18. GRB 071025: ROTSE-III Detection of Optical Counterpart
  19. GRB 071021: R-band detection and analysis
  20. GRB 071020: BTA spectroscopy
  21. GRB071021: Optical+NIR observations
  22. Possible radio detection of GRB 071021 with the VLA
  23. Optical observations of GRB 071020
  24. GRB 071021: (Relatively shallow) IR non-detections; motivation for optical spectroscopy
  25. GRB 071020: SARA observations
  26. Radio detection of GRB 071020 with the VLA
  27. GRB071010b: optical observation
  28. GRB 071021: Subaru NIR observation
  29. GRB 071021: Magellan i-band observation
  30. GRB 071021: Z-band detection
  31. GRB 071020: Fading slowly?
  32. GRB 071010B: Fading quickly
  33. GRB 071021: optical and NIR observations
  34. GRB 071021: possible high-z burst
  35. GRB 071021, Swift-BAT refined analysis
  36. GRB071018: 2nd epoch obsevations of Xinglong TNT
  37. GRB 071021: retraction of Faulkes Telescope South candidate
  38. GRB 071021: Swift-XRT Team refined analysis
  39. GRB 071021: Xinglong TNT optical Upper Limit
  40. GRB 071021 : Lulin R-band limit
  41. Konus-Wind observation of GRB 071020
  42. GRB 071021: Faulkes Telescope South optical candidate
  43. GRB 071010B: Independent Confirmation of Break
  44. GRB071020A: Xinglong TNT Optical afterglow observations
  45. GRB 071020: Swift-XRT refined analysis
  46. GRB 071020, Swift-BAT refined analysis
  47. GRB 071020A: IR Imaging with PAIRITEL
  48. GRB 071020: VLT spectroscopy
  49. GRB 071020: ROTSE-III Analysis of Optical Counterpart
  50. GRB 071020A: ROTSE-III Detection of Optical Counterpart
  51. Swift autonomous slewing re-enabled
  52. GRB071010b: optical observations
  53. GRB 071018: SARA observations
  54. GRB 071018: Swift-XRT observation
  55. GRB 071017 - Swift XRT observations
  56. VLA radio observation of GRB 071018
  57. GRB071018: Correction to the GCN 6936
  58. GRB071018: Correction to the GCN 6936
  59. GRB071018: Correction to the GCN 6936
  60. GRB071018: Correction to the title of the GCN 6936
  61. GRB 071018: Possible OT from Xinglong TNT observation
  62. GRB 071010B: Light Curve Break Confirmed
  63. GRB 071010A: Late-time Keck/LRIS photometry - possible host galaxy and jet break
  64. GRB 071018, Swift-BAT refined analysis
  65. GRB 071010B: Suzaku WAM observation of the prompt emission
  66. GRB 071013: 3rd TLS Epoch - constraints on variability
  67. GRB 071013: TNT optical data refined analysis
  68. GRB 071010B: Keck/DEIMOS emission-line redshift
  69. GRB 071013: TLS 2nd epoch - Kornienko candidate constant
  70. GRB071013: optical observations
  71. GRB 071010B: Optical observations of EST
  72. GRB 071010B: TLS 3rd Epoch - finally a break??
  73. GRB 071011: MITSuME Optical Observations
  74. GRB 070920A: deep optical observations at the NOT
  75. GRB 071010B: Photometry after 1.6 days
  76. GRB 071010B: Keck/LRIS Photometry
  77. GRB 071010B: TLS 2nd Epoch, refined analysis
  78. GRB 071013: TLS Upper Limit
  79. Correction to GCN circular no. # 6915 for GRB 071010B
  80. VLA detection of radio afterglow of GRB 071010B
  81. VLA non-detection of GRB 071011
  82. GRB 071013: optical observations at NOT
  83. GRB 071013, Swift-BAT refined analysis
  84. GRB071013: optical limit
  85. GRB 20071013: Xinglong TNT optical Upper Limit
  86. GRB 071011: Optical Limit after 13.95hrs
  87. GRB 071011: Xinglong TNT Optical afterglow observations
  88. GRB 071010B correction to GCN 6892 optical observations
  89. GRB 071011: Swift-XRT refined analysis
  90. VLA non-detection of GRB 071010A
  91. GRB 071011: NAYUTA Optical Observation, correction to GCN6886
  92. GRB 071011, Optical afterglow
  93. GRB 071011: Confirmation of P60 optical afterglow
  94. GRB 071010B: Optical Detection
  95. GRB 071011: Kanazawa Optical limits
  96. GRB 071011: P60 Optical Afterglow Candidate
  97. GRB 071011: MARGE Optical Limits
  98. GRB 071010B: Super-LOTIS upper limit
  99. GRB 071010B optical photometry
  100. GRB 071011: XRT afterglow detection

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