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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"
  1. GRB 081008: Swift detection of a burst with optical afterglow
  2. GRB 081008: ROTSE-III Detection of Optical Counterpart
  3. GRB081006B: Fermi GBM detection
  4. GRB081006: Fermi GBM detection
  5. GRB081007: Swift/UVOT Observations
  6. GRB 081007, SMARTS optical afterglow observations
  7. GRB 081007, Swift-BAT refined analysis
  8. GRB 081007: Early RAPTOR measurements of optical counterpart
  9. GRB 081007: Swift-XRT Team refined analysis
  10. GRB 081007: Gemini-south redshift
  11. GRB 081007: Enhanced Swift-XRT position
  12. GRB 081007, Faulkes Telescope North optical observations
  13. GRB 081007, SMARTS optical/IR afterglow observations
  14. GRB 081007: REM NIR and optical counterpart
  15. GRB 081007: Swift detection of a burst with optical afterglow
  16. GRB081003C: GLAST Burst Monitor detection
  17. Fermi GBM detection of additional bursts from AXP 1E1547.0-5408
  18. INTEGRAL ToO observation of the AXP 1E 1547.0-5408
  19. GRB 081003B: TAROT Calern observatory optical observations
  20. AXP 1E 1547.0-5408: Swift/UVOT Upper Limits
  21. GRB 081003B: Swift-XRT upper limit
  22. GRB 081003A: OSN optical observations
  23. GRB 081001: Further observations from OSN
  24. AXP 1E1547.0-5408: Swift-XRT Team refined analysis
  25. GRB081003B: Optical limits from Spain
  26. GRB 081003A: Swift-XRT Team position and analysis
  27. Swift-BAT refined analysis of AXP 1E1547.0-5408 (Trigger 330353)
  28. GRB 081003B: a long GRB detected with INTEGRAL
  29. GRB 080928: Fermi GBM detection
  30. AXP 1E1547.0-5408 (SGR 1550-5418): Fermi GBM detection
  31. GRB 081003: A long GRB discovered by INTEGRAL
  32. SGR 1550-5418 = AXP 1E1547.0-5408 (Trigger 330353)
  33. Swift discovery of a new Soft Gamma Repeater SGR 1550-5418
  34. Trigger 330353: Swift detection of a Galactic short soft burst
  35. GRB 081001: Observations from OSN
  36. GRB 080925: Suzaku WAM observation of the prompt emission
  37. GRB 081001: Swift UVOT Observations
  38. GRB 081001: Swift-XRT position
  39. GRB081001: optical limit from ASH-Centurion
  40. GRB081001: SuperAGILE Localization of a long GRB
  41. GRB080928: redshift retraction
  42. GRB 080928: Watcher observations
  43. GRB 080927: Fermi GBM detection
  44. GRB 080928: VLT redshift
  45. GRB080928: Gemini-South Absorption Redshift
  46. GRB 080928: Swift-XRT refined analysis
  47. GRB 080928: Swift/UVOT observations
  48. GRB 080928, Swift-BAT final refined analysis
  49. GRB 080928: GROND DETECTION
  50. GRB 080928: Enhanced Swift-XRT position
  51. GRB 080928, Swift-BAT initial refined analysis
  52. GRB 080928A: ROTSE-III Confirmation of Optical Counterpart
  53. GRB 080928: Swift detection of a burst with an optical counterpart
  54. GRB 080925: Fermi GBM Detection
  55. GRB 080920: Fermi GBM detection
  56. GRB080922, optical upper limit
  57. Swift-BAT trigger 325707 is not a GRB
  58. Swift trigger 325707: Swift/UVOT Upper Limits
  59. Swift trigger 325707: Swift-XRT upper limit
  60. Swift detection of a possible GRB (trigger 325707)
  61. GRB080916A: Suzaku WAM observation of the prompt emission
  62. GRB 080922: Swift/UVOT Upper Limits
  63. GRB080922: Swift-XRT upper limit
  64. GRB080922: A long GRB detected by INTEGRAL
  65. GRB 080913B: Fermi GBM detection
  66. Trigger 324561: IGR J08408-4503 detected by Swift
  67. GRB 080916C: Fermi GBM Spectral Analysis
  68. GRB 080919: Swift/UVOT Refined Analysis
  69. GRB 080919: Swift-XRT refined analysis
  70. GRB 080919, Swift-BAT refined analysis
  71. GRB 080916C: IRSF/SIRUS NIR Observation
  72. GRB 080916C: GROND Confirmation of the Optical Afterglow
  73. GRB 080916C: GROND Confirmation of the Optical Afterglow
  74. GRB 080919: REM NIR observations
  75. GRB 080919: Swift detection of a short burst
  76. Fermi/GBM Data Now Available
  77. GRB 080915A: GROND upper limits
  78. GRB080913: Swift-BAT spectral lag
  79. GRB 080916A: GROND lightcurve
  80. SGR 0501+4516: preliminary results of the Suzaku ToO observation
  81. GRB 080916A: Rapid PROMPT Observations
  82. GRB 080916A: Fermi GBM detection
  83. GRB 080916C: Swift UVOT Refined Analysis
  84. GRB 080916C: Swift XRT refined analysis
  85. GRB 080916B: Swift-XRT refined analysis
  86. Konus-Wind observation of GRB 080916A
  87. Konus-Wind observation of GRB 080916C
  88. GRB 080916C: GROND Detection of the Optical Afterglow Candidate
  89. GRB 080913: Konus-Wind and Swift/BAT joint spectral analysis
  90. GRB 080916C: Enhanced XRT position
  91. GRB080916A: Spectroscopic redshift
  92. GRB 080916C: Swift/XRT detection of possible afterglow
  93. GRB 080916B: Swift UVOT Refined Analysis
  94. IPN Triangulation and Energy Spectrum of GRB080916C
  95. GRB 080916B, Swift-BAT refined analysis
  96. GRB080916A: Refined Swift/UVOT Observations
  97. GRB 080915a, SMARTS optical/IR observations
  98. GRB 080916B: Enhanced Swift-XRT position
  99. GRB 080916C: Fermi LAT observation
  100. GRB 080916C: Fermi GBM Detection

Advanced

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