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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. Short X-ray Transient Detection by MAXI/GSC
  2. Konus-Wind observation of very long GRB 091123
  3. GRB 091130A: Xinglong TNT upper limit
  4. GRB 091127: Suzaku WAM observation of the prompt emission
  5. GRB 091130B: Swift-XRT team refined analysis
  6. GRB 091130B: Swift-BAT refined analysis
  7. GRB 091130B: Swift/UVOT Upper Limits
  8. GRB 091127: Skynet/PROMPT Observations of Fading
  9. GRB 091130B: MASTER observations
  10. GRB 091130B: SDSS galaxy at XRT location
  11. GRB 091130: MASTER observations
  12. GRB 091127: Radio observations
  13. Konus-Wind observation of GRB 091127
  14. GRB 091127: optical observations
  15. GRB 091127: LABOCA/APEX submm observations
  16. GRB 091127: Further NOT optical observations
  17. GRB 091127: Fermi GBM detection
  18. GRB 091127: MASTER early optical transient polarimetry
  19. GRB 091127: Gemini-N redshift
  20. GRB 091127: Swift-XRT afterglow detection and analysis
  21. GRB 091127: Swift/UVOT observations
  22. GRB 091127: CAHA 1.23m I-band observations
  23. GRB 091127: Swift-BAT refined analysis
  24. GRB 091127: NOT observations
  25. GRB 091127 : GROND observations
  26. GRB 091127: REM NIR afterglow detection
  27. GRB 091127: Swift/UVOT Detection of an Optical Afterglow
  28. GRB 091127: Liverpool Telescope afterglow candidate
  29. IPN Triangulation of GRB091120
  30. Konus-Wind observation of GRB 091120
  31. GRB 091117A: Suzaku WAM observation of the prompt emission
  32. GRB 091117: TNG optical observations
  33. GRB 091117A: Swift/UVOT followup observations
  34. GRB 091117: 2nd epoch of Magellan optical observations
  35. GRB 091117: VLA radio observations
  36. GRB 091117: Swift-XRT observations
  37. GRB 091117 BAT refined analysis
  38. GRB 091117: Evidence for Variability of XRT Source #1
  39. GRB091117: Gemini South Observations
  40. GRB 091117: Swift XRT refined analysis
  41. GRB 091117: Gemini-North spectroscopy of DSS galaxy
  42. Konus-Wind observations of GRB 091117A
  43. GRB 091117: Magellan optical observations
  44. GRB 091117: XRT source coincident with a DSS galaxy
  45. GRB 091112: Suzaku WAM observation of the prompt emission
  46. GRB 091102A: Suzaku WAM observation of the prompt emission
  47. GRB 091109B: Suzaku WAM observation of the prompt emission
  48. GRB091111: Swift XRT refined analysis
  49. Konus-Wind and Konus-RF observations of GRB 091031
  50. GRB 091112: Swift-BAT refined analysis
  51. GRB 091112: Fermi GBM observation
  52. GRB 091031: Fermi LAT detection of a faint burst
  53. GRB 091111: BOOTES-3 contemporaneous imaging
  54. GRB 091111: a faint long GRB detected with INTEGRAL
  55. GRB 091109A: GROND and VLT observations
  56. GRB 091109B: Swift/UVOT Upper Limits
  57. GRB 091109B: VLT afterglow confirmation
  58. GRB 091109B: Swift-XRT Team refined analysis
  59. GRB 091109b: Magellan Observations
  60. GRB 091109B: Swift-BAT refined analysis
  61. GRB 091109B: Optical limits from Watcher
  62. GRB 091109B: ROTSE-III Optical Limits
  63. GRB091109: Correction to GCN 10139
  64. GRB 091109: Swift-XRT refined analysis
  65. GRB 091109: BOOTES-3 observations
  66. GRB 091109: Swift/UVOT observations
  67. GRB 091109: Faulkes Telescope South observations
  68. GRB 091109: Swift-BAT refined analysis
  69. GRB 091029: Observations from Stardome Observatory
  70. GRB 091104: Swift-BAT refined analysis
  71. GRB 091104: Swift XRT Refined Analysis
  72. GRB 091104: Swift/UVOT Upper Limits
  73. GRB091026 : IRSF NIR upper limit
  74. GRB091102 : MOA optical upper limit
  75. GRB 091102: LABOCA/APEX submm observations
  76. Fermi LAT Upper Limits on GRB 091010
  77. GRB 091102 : Faulkes Telescope South Upper Limits
  78. GRB 091102A: Fermi GBM observation
  79. GRB 091102: Swift-XRT refined analysis
  80. GRB 091102: Swift/UVOT Upper Limits
  81. GRB 091102: GROND Upper Limits
  82. GRB 091102: BOOTES-3 observations
  83. GRB 091102: Swift-BAT refined analysis
  84. GRB 091102: Swift/XRT localization
  85. GRB 091102: ROTSE-III Optical Limits
  86. GRB 091102: Swift/UVOT Finding Chart Observation
  87. GRB 091024: optical observations
  88. GRB 091031: Fermi GBM detection
  89. GRB 091024: Fermi LAT upper limits
  90. GRB 090926a, SMARTS optical/IR afterglow observations
  91. GRB 091018: Skynet/PROMPT Observations of Possible Host Galaxy
  92. GRB 091029, SMARTS optical/IR afterglow observations
  93. GRB 091018, SMARTS optical/IR afterglow observations
  94. GRB 090920: Skynet/DSO Detection
  95. GRB091029: Swift/UVOT observations
  96. GRB 091029: Skynet/PROMPT Continued Observations of Fading
  97. GRB 091029: Swift XRT refined analysis
  98. GRB 091029: BOOTES-3 observations
  99. GRB 091029: Swift-BAT refined analysis
  100. GRB091024 optical observations

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