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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 160408A: Swift-BAT refined analysis
  2. GRB 160408A: Gemini optical observations
  3. GRB 160408A: Enhanced Swift-XRT position
  4. GRB 160408A: Swift detection of a short burst
  5. IPN Triangulation of GRB 160406A (short/hard)
  6. LIGO/Virgo G211117: 10.4m GTC follow-up of PS15dpn
  7. GRB 160401A: Swift-XRT observations
  8. GRB 160401A: Swift/UVOT Upper Limits
  9. GRB 160401A: Zadko observatory - Gingin optical observations
  10. GRB 160401A: LT observations
  11. GRB 160401A: Swift ToO observations
  12. GRB 160401A: MASTER-IAC prompt optical observations
  13. GRB 160401A: a long GRB detected by INTEGRAL
  14. GRB 160327A: Continued RATIR Optical and NIR Observations
  15. LIGO/Virgo G211117: LOFAR follow-up
  16. GRB 160324A: CALET Gamma-Ray Burst Monitor detection
  17. GRB 160327A: Early RAPTOR Limits
  18. GRB 160327A: JCMT SCUBA-2 sub-mm observation
  19. GRB 160327A: Imaging and spectroscopy from GTC
  20. Konus-Wind observation of GRB 160325A
  21. GRB 160327A: Continued RATIR Optical and NIR Observations
  22. GRB 160327A: KAIT optical afterglow confirmation
  23. GRB 160327A: Mondy optical upper limit
  24. GRB 160327A: Swift-BAT refined analysis
  25. GRB 160327A: Swift/UVOT Upper Limits
  26. GRB 160327A: Swift-XRT refined Analysis
  27. GRB 160327A: Enhanced Swift-XRT position
  28. GRB 160327A: RATIR Optical and NIR Afterglow Detection
  29. GRB 160327A: Swift detection of a burst
  30. GRB 160325A, Swift-BAT refined analysis
  31. GRB 160325A: GROND Upper Limits
  32. GRB 160325A: Swift-XRT refined Analysis
  33. GRB 160325A: Further Swift/UVOT Observations
  34. GRB 160325A: afterglow confirmation
  35. GRB 160325A: Enhanced Swift-XRT position
  36. GRB160325A Swift/UVOT Detection
  37. GRB 160325A: Fermi-LAT detection
  38. Swift Trigger 680457 is not a GRB
  39. LIGO/Virgo G211117: CALET GBM Observations
  40. GRB 160325A: Fermi GBM detection
  41. GRB160325A: REM NIR observations
  42. GRB 160325A: Swift detection of a burst
  43. Swift detects GX 301-2 in very high state
  44. Fermi Gamma-ray Burst Monitor trigger 160323546 is not a GRB
  45. GRB 160321A: AbAO optical observations
  46. GRB 160321A: Possible RATIR Optical and NIR Detections
  47. GRB 160321A: Swift/UVOT Upper Limits
  48. GRB 160321A: Swift-BAT refined analysis
  49. GRB 160321A: Swift-XRT refined Analysis
  50. GRB 160316A: CALET Gamma-Ray Burst Monitor detection
  51. GRB 160321A: Enhanced Swift-XRT position
  52. GRB 160321A: MASTER observations zero Galaxy latitude GRB
  53. GRB 160321A: Swift detection of a probable burst
  54. GRB 160310A: Terskol 2-m observations
  55. IPN Triangulation of GRB 160310A
  56. LIGO/Virgo G211117: EWE for NOWT follow-up of northern sky
  57. SGR 0755-2933, Swift-BAT refined analysis
  58. GRB 160131A: 15 GHz upper limits from AMI-LA
  59. GRB 160310A: A further Swift-XRT observation, no afterglow detected
  60. Swift detection of a likely new SGR: SGR 0755-2933
  61. GRB 160314A: Continued RATIR Optical and NIR Observations
  62. GRB 160313A: Mondy optical upper limit
  63. GRB 160314A: GROND optical/NIR observations
  64. GRB 160314A: ISON-Ussuriysk optical upper limit, updated photometry and correction of GCN 19184
  65. GRB 160314B: Fermi GBM observation
  66. GRB 160314B: Fermi-LAT detection
  67. GRB 160314A: RATIR Optical and NIR Observations
  68. GRB 160314A: Mondy optical observations
  69. GRB 160313A: Swift/UVOT Upper Limits
  70. LIGO/Virgo G194575: EWE for NOWT follow-up of northern sky
  71. GRB 160314A: VLT/X-shooter redshift
  72. GRB 160314A: NOT afterglow observations
  73. GRB 160314A: Swift-XRT refined Analysis
  74. GRB 160314A: Optical observations from OSN
  75. GRB 160314A: Swift-BAT refined analysis
  76. GRB 160314A: Swift/UVOT Detection
  77. GRB 160228A: GROND afterglow confirmation and X-shooter host candidate redshift
  78. GRB 160314A: Enhanced Swift-XRT position
  79. GRB 160314A: ISON-Ussuriysk optical upper limit
  80. GRB 160314A: Weihai optical upper limit
  81. GRB 160314A: Swift detection of a burst
  82. GRB 160313A, Swift-BAT refined analysis
  83. Fermi GBM trigger 479509107/160312874 is not a GRB
  84. GRB 160313A: Chante-Perdrix Observatory optical observations
  85. GRB 160313A: MASTER-Net optical observations
  86. GRB 160313A: LT observations
  87. GRB 160313A: Swift-XRT refined Analysis
  88. GRB 160313A: TAROT Calern observatory optical observations
  89. GRB 160313A: Enhanced Swift-XRT position
  90. GRB 160313A: RATIR Optical and NIR Observations
  91. GRB 160313A: SAO RAS observations
  92. GRB 160313A: Swift detection of a burst
  93. GRB 160310A: MASTER-Kislovods observations
  94. GRB 160310A: Further NOT observations
  95. GRB 160310A: Swift/UVOT Upper Limits
  96. Konus-Wind observation of GRB 160310A (possible ultra-long GRB?)
  97. GRB 160310A: RATIR Optical and NIR Observations
  98. GRB 160307A: CALET Gamma-Ray Burst Monitor detection of a possible short GRB
  99. GRB 160310A: NOT optical observations
  100. GRB 160310A: LCOGT-SAAO optical upper limits

Advanced

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