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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"

19857 results found.

  1. GRB 071028: Swift detection of a burst
  2. GRB 071003: Infrared Photometry with Keck Adaptive Optics
  3. GRB071021: MARGE Optical Limits
  4. GRB071020, optical upper limit
  5. GRB 071025: SARA VRI upper limits
  6. GRB 071025: SQIID JHK photometry
  7. Swift UVOT upper limits
  8. GRB071025: Xinglong TNT I-band upper limit
  9. GRB 071025: Swift-XRT Team refined analysis
  10. GRB071021 : CFHT Ks-band observation
  11. GRB 071025a: PAIRITEL observations
  12. GRB071025: REM NIR afterglow
  13. GRB 071025: Swift detection of a burst
  14. GRB 071021: R-band detection and analysis
  15. GRB 071020: BTA spectroscopy
  16. Possible radio detection of GRB 071021 with the VLA
  17. GRB 071021: (Relatively shallow) IR non-detections; motivation for optical spectroscopy
  18. GRB 071020: SARA observations
  19. Radio detection of GRB 071020 with the VLA
  20. GRB071021: MITSuME Okayama Optical Upper Limits
  21. GRB 071021: Z-band detection
  22. GRB071018: 2nd epoch obsevations of Xinglong TNT
  23. GRB 071021: Xinglong TNT optical Upper Limit
  24. GRB 071021 : Lulin R-band limit
  25. GRB 071021: Swift detection of a burst
  26. GRB071020A: Xinglong TNT Optical afterglow observations
  27. GRB 071020A: IR Imaging with PAIRITEL
  28. GRB071020 - SDSS Pre-burst Observations
  29. GRB 071020: Swift detection of a bright burst
  30. GRB 071018: Mercator Telescope optical observations
  31. GRB 071018: SARA observations
  32. GRB 071018: Swift-XRT observation
  33. GRB 071017 - Swift XRT observations
  34. GRB 071018: Possible OT from Xinglong TNT observation
  35. GRB 071010B: Light Curve Break Confirmed
  36. GRB 071010A: Late-time Keck/LRIS photometry - possible host galaxy and jet break
  37. GRB 071018, Swift-BAT refined analysis
  38. GRB 071013: 3rd TLS Epoch - constraints on variability
  39. GRB 071013: TNT optical data refined analysis
  40. GRB 071013: TLS 2nd epoch - Kornienko candidate constant
  41. GRB 071011: MITSuME Optical Observations
  42. GRB 070920A: deep optical observations at the NOT
  43. GRB 071010B: Keck/LRIS Photometry
  44. GRB 071013: TLS Upper Limit
  45. VLA non-detection of GRB 071011
  46. GRB 071013: Optical observations
  47. GRB 071013: optical observations at NOT
  48. GRB071010B, BVRcIc field calibration
  49. GRB 20071013: Xinglong TNT optical Upper Limit
  50. GRB 071010C Swift-BAT detection of a burst
  51. GRB 071011: Optical Limit after 13.95hrs
  52. GRB 071010B correction to GCN 6892 optical observations
  53. GRB 071011: Swift-XRT refined analysis
  54. VLA non-detection of GRB 071010A
  55. GRB 071011: NAYUTA Optical Observation, correction to GCN6886
  56. GRB 071011: Confirmation of P60 optical afterglow
  57. GRB 071010B: Optical Detection
  58. GRB 071011: Kanazawa Optical limits
  59. GRB 071011: P60 Optical Afterglow Candidate
  60. GRB 071011: MARGE Optical Limits
  61. GRB 071010B: Super-LOTIS upper limit
  62. GRB 071010B optical photometry
  63. GRB 071011: XRT afterglow detection
  64. GRB 071011: NAYUTA Optical Observation
  65. GRB 071010A: Continued Keck Imaging
  66. GRB 071010B: Bright OT confirmed with TLS
  67. Optical Observation: GRB 071010
  68. Optical observations: GRB 071010A
  69. GRB071010B: Swift/XRT detection
  70. GRB 071010A: Keck/LRIS Photometry
  71. GRB 071010 REM NIR observations
  72. GRB 071010: TAROT La Silla observatory detection of the afterglow
  73. Radio detection of GRB 071003 with the VLA
  74. GRB 070810B: further XRT analysis
  75. Konus-Wind observation of GRB 071003
  76. GRB 071003: Possible rebrightening
  77. GRB 071003 : Lulin R-band observations
  78. GRB 071003: OA power-law decay indices from KAIT
  79. GRB 071003: P60 Confirmation of Optical Afterglow
  80. Faulkes Telescope South observations of GRB 071001
  81. GRB 071001: Swift detection of a burst
  82. VLA observation of GRB 070923
  83. GRB 070911, SMARTS optical/IR afterglow observations
  84. GRB070925: Swift-XRT Afterglow confirmation
  85. GRB 070925: Gemini South Imaging
  86. GRB 070920B: ROTSE-III Early Optical Limits
  87. GRB 070920B: TAROT La Silla observatory optical observations
  88. INTEGRAL ToO observations of SGR1806-20
  89. GRB 070920B: NOT optical observations
  90. GRB 070920: TAROT Calern observatory optical observations
  91. SGR1806-20: Swift-BAT detection of enhanced activity
  92. GRB 070917: P60 Observations
  93. GRB 070917: MITSuME Akeno Ic upper limit
  94. GRB 070917: R band observations
  95. GRB 070913: Swift-XRT detection of the possible X-ray afterglow
  96. GRB 070809: The Swift evidence for the SHB nature of this burst
  97. GRB 070913: Swift-BAT refined analysis
  98. GRB 070913: SMARTS optical/IR observations
  99. GRB 070913: TAROT La Silla observatory optical observations
  100. Swift-BAT Notices back to autonomous real-time distribution

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