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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 160422A: Fermi GBM observation
  2. GRB 160422A: Swift ToO observations
  3. GRB 160422A: Fermi-LAT Detection
  4. GRB 160419A, Swift-BAT refined analysis
  5. GRB 160419A: Fermi GBM detection
  6. GRB 160419A: Swift detection of a burst
  7. Fermi GBM trigger 482632364/160418023 is not a GRB
  8. GRB 160417A: GMG observations
  9. GRB 160417A: Swift-BAT refined analysis
  10. GRB 160417A: Swift/UVOT Detection
  11. GRB 160417A: iTelescope T11 optical observations
  12. GRB 160417A: Swift-XRT refined Analysis
  13. GRB 160417A: MITSuME Okayama upper limits
  14. GRB 160417A: Enhanced Swift-XRT position
  15. GRB 160417A: KAIT optical afterglow confirmation
  16. GRB 160417A: Swift detection of a burst with an optical counterpart
  17. LIGO/Virgo G211117: EWE for NOWT of 12 days follow-up of northern sky
  18. GRB 160412A: GROND upper limits
  19. GRB 160411A - Gemini-S afterglow candidate
  20. Konus-Wind observation of GRB 160409A
  21. GRB 160410A: SMARTS optical/IR observations
  22. LIGO Virgo G211117: Additional MWA Observations
  23. GRB 160410A: TLS Tautenburg observations
  24. GRB 160412A: Swift/UVOT Upper Limits
  25. Swift Trigger 682614 is not a GRB
  26. GRB 160410A: JCMT SCUBA-2 sub-mm observation
  27. GRB 160409A: Swift-XRT observations
  28. GRB 160409A found in Swift BAT ground analysis
  29. GRB 160412A: Swift-XRT refined Analysis
  30. GRB 160411A: Swift-BAT refined analysis of the short burst
  31. GRB 160412A: Swift-BAT refined analysis
  32. GRB 160410A: further NOT optical observations
  33. GRB 160412A: Enhanced Swift-XRT position
  34. GRB 160412A: Swift detection of a burst
  35. GRB 160408A: CALET Gamma-Ray Burst Monitor detection
  36. GRB 160409A: Swift ToO observations
  37. GRB 160410A: NOT observations of the afterglow
  38. GRB 160408A: 6.0 GHz VLA upper limit
  39. GRB 160411A: Gemini-S optical observations
  40. GRB 160411A: GROND Optical/NIR upper limits
  41. GRB 160411A: Swift/UVOT Upper Limits
  42. GRB 160410A: UKIRT near-IR upper limits
  43. GRB 160411A: Fermi GBM detection
  44. Konus-Wind observation of GRB 160410A (short/hard)
  45. GRB 160410A: TAROT La Silla observatory early optical observations
  46. GRB 160411A: Swift-XRT refined Analysis
  47. GRB 160410A: MITSuME Akeno optical upper limits
  48. GRB 160411A: MASTER-NET early optical observations.
  49. GRB 160411A: Enhanced Swift-XRT position
  50. GRB 160410A: Swift-XRT refined Analysis
  51. GRB 160411A: Swift-XRT observations
  52. GRB 160410A: GMG observation
  53. GRB 160411A: Swift detection of a short burst
  54. GRB 160410A: Keck-I/LRIS redshift
  55. GRB 160410A: Skynet PROMPT-CTIO observations of the optical afterglow
  56. GRB 160410A: Swift-BAT refined analysis of the short GRB
  57. GRB 160410A: Swift/UVOT Detection
  58. GRB 160410A: VLT/X-shooter redshift
  59. GRB 160410A: Enhanced Swift-XRT position
  60. GRB 160410A: GROND optical detection
  61. GRB 160410A: Swift detection of a (possibly-short) burst with an optical counterpart
  62. GRB 160408A: GMG observation limit
  63. GRB 160408A: Gemini afterglow confirmation
  64. GRB 160408A: TLS Tautenburg observations
  65. GRB 160408A: Swift/UVOT Upper Limits
  66. GRB 160408A: Swift-XRT refined Analysis
  67. GRB 160408A: Fermi GBM detection
  68. GRB 160406A: Fermi GBM observation
  69. GRB 160408A: Swift-BAT refined analysis
  70. GRB 160408A: Gemini optical observations
  71. GRB 160408A: Enhanced Swift-XRT position
  72. GRB 160408A: Swift detection of a short burst
  73. IPN Triangulation of GRB 160406A (short/hard)
  74. LIGO/Virgo G211117: 10.4m GTC follow-up of PS15dpn
  75. GRB 160401A: Swift-XRT observations
  76. GRB 160401A: Swift/UVOT Upper Limits
  77. GRB 160401A: Zadko observatory - Gingin optical observations
  78. GRB 160401A: LT observations
  79. GRB 160401A: Swift ToO observations
  80. GRB 160401A: MASTER-IAC prompt optical observations
  81. GRB 160401A: a long GRB detected by INTEGRAL
  82. GRB 160327A: Continued RATIR Optical and NIR Observations
  83. LIGO/Virgo G211117: LOFAR follow-up
  84. GRB 160324A: CALET Gamma-Ray Burst Monitor detection
  85. GRB 160327A: Early RAPTOR Limits
  86. GRB 160327A: JCMT SCUBA-2 sub-mm observation
  87. GRB 160327A: Imaging and spectroscopy from GTC
  88. Konus-Wind observation of GRB 160325A
  89. GRB 160327A: Continued RATIR Optical and NIR Observations
  90. GRB 160327A: KAIT optical afterglow confirmation
  91. GRB 160327A: Mondy optical upper limit
  92. GRB 160327A: Swift-BAT refined analysis
  93. GRB 160327A: Swift/UVOT Upper Limits
  94. GRB 160327A: Swift-XRT refined Analysis
  95. GRB 160327A: Enhanced Swift-XRT position
  96. GRB 160327A: RATIR Optical and NIR Afterglow Detection
  97. GRB 160327A: Swift detection of a burst
  98. GRB 160325A, Swift-BAT refined analysis
  99. GRB 160325A: GROND Upper Limits
  100. GRB 160325A: Swift-XRT refined Analysis

Advanced

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