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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"

32507 results found.

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

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