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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"

5843 results found.

  1. GRB 160910A: Global MASTER Net OT detection before LAT alert
  2. GRB 160912A: Swift detection of a burst
  3. IceCube HESE 160814: MASTER OT J130845.02-323254.9 as the possible source of the high energy neutrino
  4. GRB 160905A: Swift detection of a burst with an optical counterpart
  5. GRB 160827A: Swift detection of a burst
  6. GRB 160825A: not localized by Swift
  7. IPN Triangulation of GRB 160820A (short/hard)
  8. GRB 160821B: Swift detection of a short burst
  9. GRB 160814A: MAXI/GSC detection
  10. Swift Trigger 707545 is likely 4U 1850-03/GS1843-02
  11. GRB160804A: MASTER-SAAO observation
  12. IPN Triangulation of GRB 160802A
  13. GRB 160804A: Swift/UVOT Detection
  14. GRB 160801A: SAO RAS optical observations
  15. GRB 160801A: Swift detection of a burst
  16. GRB 160716A: Swift detection of a burst
  17. GRB 160709A: MASTER early imaging Swift BAT error box
  18. GRB 160709A, Swift-BAT detection and localization
  19. GRB 160709A: Global MASTER Net Fermi GBM Alerts observations
  20. GRB 160709A: Fermi GBM Observations
  21. GRB 160709A: Fermi-LAT detection
  22. SGR 1935+2154: CALET Gamma-Ray Burst Monitor detections
  23. GRB 160703A: Swift-XRT afterglow detection
  24. GRB 160705A/MAXI J0748-149: MAXI/GSC detection
  25. GRB 160630A: Swift detection of a burst
  26. GRB 160607A: Swift detection of a bright burst
  27. GRB 160601A: MITSuME Okayama Ks-band upper-limit
  28. GRB 160521B: Swift-XRT afterglow detection
  29. Konus-Wind observation of GRB 160521B
  30. GRB 160525B: Prompt enhanced Swift-XRT position
  31. GRB 160525B: Swift detection of a burst
  32. GRB 160521B: Swift-XRT observations
  33. GRB 160521B: Fermi-LAT detection
  34. GRB 160521B: Fermi GBM detection
  35. Konus-Wind observation of a bright burst from SGR 1935+2154
  36. FERMI GBM bursts from the magnetar SGR 1935+2154
  37. Fermi GBM triggers of SGR 1935+2154
  38. Trigger 686761: Swift detection of a bright burst from SGR 1935+2154
  39. GRB 160509A MASTER-NET observations
  40. Fermi GBM trigger 484574960/160510506 is not a GRB
  41. GRB 160509A: Fermi GBM Detection
  42. GRB 160509A: Fermi-LAT prompt detection of a very bright burst
  43. GRB 160506A: Swift detection of a burst
  44. ICECUBE-160427A : Pan-STARRS imaging and optical transients in the field
  45. VERITAS rapid follow-up observations of IceCube event 160427A
  46. GRB 160501A: Swift detection of a burst
  47. GRB 160325A: Skynet PROMPT-CTIO observations of the optical afterglow
  48. LIGO/Virgo G197392 / LVT151012: Identification of a GW CBC Candidate
  49. LIGO/Virgo G211117: EWE for NOWT of 12 days follow-up of northern sky
  50. GRB 160409A found in Swift BAT ground analysis
  51. GRB 160412A: Swift detection of a burst
  52. GRB 160411A: Gemini-S optical observations
  53. GRB 160411A: GROND Optical/NIR upper limits
  54. Konus-Wind observation of GRB 160410A (short/hard)
  55. GRB 160410A: Swift detection of a (possibly-short) burst with an optical counterpart
  56. LIGO/Virgo G211117: LOFAR follow-up
  57. GRB 160327A: Early RAPTOR Limits
  58. GRB 160327A: Imaging and spectroscopy from GTC
  59. GRB 160327A: KAIT optical afterglow confirmation
  60. GRB 160327A: Swift detection of a burst
  61. GRB 160325A: Swift detection of a burst
  62. LIGO/Virgo G211117: EWE for NOWT follow-up of northern sky
  63. LIGO/Virgo G194575: EWE for NOWT follow-up of northern sky
  64. GRB 160228A: GROND afterglow confirmation and X-shooter host candidate redshift
  65. Trigger 677981: Swift detection of IGRJ17091-3624
  66. GRB 160228A: RATIR Optical and NIR Observations
  67. GRB 160228A: Prompt enhanced Swift-XRT position
  68. GRB 160228A: Swift detection of a burst
  69. GRB 160227A: MAXI/GSC detection
  70. GRB 160227A: Swift detection of a burst with an optical counterpart
  71. GRB 160223B: CALET Gamma-Ray Burst Monitor detection
  72. GRB 160223A: Swift-XRT afterglow detection
  73. GRB 160223B: MASTER-Amur early observations
  74. GRB 160223B: Fermi GBM observation
  75. GRB 160223B: A long GRB detected by INTEGRAL
  76. GRB 160223A: GROND optical/NIR afterglow
  77. GRB 160220A: nIR observations at AAT
  78. LIGO/Virgo GW150914: BOOTES-3 simultaneous imaging
  79. LIGO/Virgo G184098: Correction for GCN Circular 18361
  80. LIGO/Virgo G184098: MAXI/GSC search for an X-ray counterpart of GW150914
  81. LIGO/Virgo G211117: LOFAR follow-up
  82. GRB 160203A: Skynet PROMPT-CTIO observations of the optical afterglow
  83. GRB 160203A: LCOGT-Cerro Tololo optical afterglow confirmation
  84. GRB 160131A: LCOGT-FTN optical afterglow observations
  85. GRB160131.35 MASTER-Net OT detection
  86. GRB 160121A: GROND Afterglow observations
  87. LIGO/Virgo G184098: MASTER final result
  88. Konus-Wind observation of GRB 160113A
  89. GRB 160117B: Swift detection of a burst with optical counterpart
  90. IPN Triangulation of GRB 160113A
  91. GRB 151225A: Correction to the trigger time of GCN 18724
  92. GRB 160113A: Fermi GBM detection
  93. GRB 160113A: iPTF P48 Observations and Optical Transient Candidates
  94. LIGO/Virgo G184098: Updated FAR estimate
  95. LIGO/Virgo G211117: Subaru Hyper Suprime-Cam follow-up observation
  96. GRB 160107A: MAXI/GSC detection
  97. Konus-Wind observation of GRB 151225A
  98. IPN Triangulation of GRB 151225A (short/hard)
  99. LIGO/Virgo G211117: Summary of Pan-STARRS transients
  100. LIGO/Virgo G211117: LOFAR follow-up

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