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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 160521B: 15 GHz upper limits from AMI
  2. GRB 160624A: Prompt enhanced Swift-XRT position
  3. GRB 160623A: Mondy optical observations
  4. GRB 160624A: Swift detection of a short burst
  5. Swift detection of a dust-scattered halo around GRB 160623A
  6. GRB 160623A: Swift-XRT afterglow detection
  7. GROND observations of GRB 160622A/SNR RCW 103/SGR 1617-5103
  8. Trigger 701182: Swift detection of SGR 1935+2154
  9. GRB 160623A: Fermi GBM detection/observation
  10. Konus-Wind observation of GRB 160623A
  11. GRB 160623A / Galactic transient: Fermi-LAT detection
  12. GRB 160623A: Swift ToO observations
  13. SGR 1617-5103 (BAT trigger 700791): Enhanced Swift-XRT position.
  14. Swift-BAT refined analysis of the recent outburst from SGR 1617-5103 (a.k.a. 1E 161348-5055 and 2E 1613.5-5053)
  15. Fermi GBM Trigger 160622573 is not a GRB
  16. BAT trigger 700791 (possible GRB 160622A) is SNR RCW 103
  17. GRB 160622A: Swift detection of a possible short GRB or a new SGR
  18. More FERMI GBM bursts from the magnetar SGR 1935+2154
  19. SGR 1935+2154: MAXI/GSC detection
  20. Fermi GBM trigger 488128598/160620637 is not a GRB
  21. Fermi GBM trigger 487974449/160618852 is not a GRB
  22. LIGO/Virgo G211117 / GW151226: Sky maps and other data available in LOSC
  23. LIGO/Virgo G197392 / LVT151012: Sky maps and other data available in LOSC
  24. LIGO/Virgo G211117/GW151226: serendipitous XMM-Newton slew observations
  25. Konus-Wind observation of GRB 160612A
  26. GRB 160612A: Swift-XRT observations
  27. BAT detection and localization of GRB 160612A
  28. GRB 160612A: Swift ToO observations
  29. IPN Triangulation of GRB 160612A (short/hard)
  30. GRB 160521A: 15 GHz detections and upper limit from AMI
  31. GRB 160519A: 15 GHz upper limits from AMI
  32. GRB 160509A: 15 GHz upper limits from AMI
  33. GRB 160612A: Fermi GBM detection
  34. GRB 160611A: Swift/UVOT observations
  35. GRB 160611A: Swift-BAT refined analysis
  36. Swift Trigger 690738 is not an astrophysical event
  37. GRB 160611A: Swift-XRT refined Analysis
  38. GRB 160611A: GCN19525 OT is known star
  39. GRB160611.9 MASTER-Net OT detection
  40. GRB 160611A: Enhanced Swift-XRT position
  41. GRB 160611A: Swift-XRT observations
  42. GRB 160611A: Swift detection of a burst
  43. SWIFT J174540.2-290037, Swift-BAT refined analysis (trigger 690197)
  44. GRB 160525C: Astrosat CZTI detection
  45. GRB 160508A: Astrosat CZTI detection
  46. SWIFT J174540.2-290037, Swift-BAT refined analysis (trigger 689956)
  47. GRB 160607A CALET Gamma-Ray Burst Monitor detection
  48. Swift detection of SWIFT J174540.2-290037
  49. Swift detection of SWIFT J174540.2-290037
  50. Trigger 689956: Swift detection of a source near the Galactic center
  51. GRB 160607A: Swift/UVOT Upper Limits
  52. GRB 160607A: GROND confirmation of the afterglow
  53. Konus-Wind observation of GRB 160607A
  54. GRB 160504A: 15 GHz upper limits from AMI
  55. GRB 160417A: 15 GHz upper limits from AMI
  56. GRB 160408A: 15 GHz upper limits from AMI
  57. GRB 160607A: candidate optical afterglow from the NOT
  58. GRB 160607A: Swift-BAT refined analysis
  59. Trigger 689353 (possible transient near Sgr A*), Swift-BAT refined analysis
  60. GRB 160607A: Swift-XRT refined Analysis
  61. GRB 160607A: Enhanced Swift-XRT position
  62. GRB 160607A: Swift detection of a bright burst
  63. GRB 160530A: further Swift-XRT follow-up observations
  64. Fermi GBM trigger 486907024/160606498 is not a GRB
  65. Trigger 689353: Swift detection of a transient near Sgr A*
  66. GRB 160601A: AbAO optical observations
  67. GRB 160601A: Discovery Channel Telescope Limits
  68. GRB 160601A: Swift/UVOT Upper Limits
  69. GRB 160601A: MITSuME Akeno optical upper limits
  70. GRB 160601A: Swift-BAT refined analysis
  71. Fermi GBM trigger 486562774/160602514 is not a GRB
  72. GRB160601A: Gemini Imaging
  73. GRB 160601A: GTC observations confirming transient source decay
  74. GRB 160601A: Mondy optical observations, photometry of NOT sources
  75. GRB160601A: Kanata Telescope I- and Ks-bands upper limits
  76. GRB160601A: NOT afterglow confirmation
  77. GRB 160530B CALET Gamma-Ray Burst Monitor detection
  78. GRB 160601A: Swift-XRT refined Analysis
  79. GRB160601A: NOT detection of an afterglow candidate
  80. GRB 160601A: Enhanced Swift-XRT position
  81. GRB 160601A: Mondy optical observations
  82. GRB 160601A: MITSuME Okayama Ks-band upper-limit
  83. GRB 160530A: Swift follow-up and X-ray afterglow candidate
  84. GRB 160601A: MITSuME Okayama upper limits
  85. GRB 160601A: MASTER-Net observations
  86. GRB 160601A: Swift detection of a short hard burst
  87. Konus-Wind observation of GRB 160530A
  88. IPN Triangulation of GRB 160530A
  89. GRB 160525B: MITSuME Akeno optical upper limits
  90. GRB 160530B: Fermi GBM Detection
  91. GRB 160530A: discovery with the Compton Spectrometer and Imager
  92. GRB 160530A: Tiled Swift observations
  93. GRB 160525C: CALET Gamma-Ray Burst Monitor detection
  94. GRB 160525B: Mondy optical upper limit
  95. GRB 160525B: Khureltogot optical upper limit
  96. GRB 160525B: Swift-BAT refined analysis
  97. GRB 160525B: Swift-XRT refined Analysis
  98. GRB 160525B: Nanshan optical upper limit
  99. GRB 160525B: Swift/UVOT Detection
  100. GRB 160521B: Swift-XRT afterglow detection

Advanced

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