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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"

3050 results found.

  1. GRB 160117A: Swift-XRT observations
  2. GRB 160117B: Swift-XRT refined Analysis
  3. LIGO/Virgo G211117: Further Swift-XRT sources
  4. GRB 160113A: Swift-XRT observations
  5. LIGO/Virgo G211117: Swift observations of PS15dpn
  6. LIGO/Virgo G211117: VISTA imaging
  7. LIGO/Virgo G211117: Further Swift-XRT sources
  8. GRB 160104A: Swift-XRT refined Analysis
  9. GRB 160104A: MITSuME Okayama Ks-band upper-limit
  10. GRB 160102A: Swift-XRT observations
  11. GRB 160101A: Swift/UVOT Detection
  12. GRB 160101A: Swift-XRT afterglow detection
  13. GRB 151228A: Correction to GCN 18770
  14. LIGO/Virgo G211117: SkyMapper observations and transient candidate
  15. GRB 151228A: Swift-XRT refined Analysis
  16. GRB 151229A: Swift-XRT refined Analysis
  17. GRB 151228B: Swift-XRT refined Analysis
  18. LIGO/Virgo G211117: Further Swift-XRT sources
  19. LIGO/Virgo G211117: Further Swift-XRT sources
  20. LIGO/Virgo G211117: Swift-XRT sources
  21. GRB 151215A: Swift-XRT refined Analysis
  22. GRB 151212A: Swift-XRT afterglow detection
  23. GRB 151210A: Swift-XRT refined Analysis
  24. GRB 151205B: further Swift-XRT observations
  25. GRB 151205C: Swift-XRT observations
  26. GRB 151205A: Swift-XRT refined Analysis
  27. GRB 151122A: Further Swift-XRT observations, no afterglow detected.
  28. GRB 151127A: Swift-XRT refined Analysis
  29. GRB 151122A: Swift-XRT observations
  30. Swift Trigger 664610 is not astrophysical
  31. GRB 151120A: Swift-XRT afterglow detection
  32. GRB 151118A: Swift-XRT refined Analysis
  33. GRB 151114A: Swift-XRT refined Analysis
  34. GRB 151112A: Swift-XRT refined Analysis
  35. GRB 151111A: Swift/UVOT upper limits
  36. GRB 151111A: Swift-XRT refined Analysis
  37. LIGO/Virgo G194575: Swift observations if iPTF15dld
  38. GRB 151031A: Swift-XRT refined Analysis
  39. GRB 151029A: Swift-XRT refined Analysis
  40. GRB 151027B: Swift-XRT refined Analysis
  41. GRB 151027A: Swift-XRT refined Analysis
  42. GRB 151023A: Swift-XRT refined Analysis
  43. GRB 151022A: Swift-XRT refined Analysis
  44. LIGO/Virgo G194575: Identification of a GW CBC Candidate
  45. GRB 151022A: MITSuME Okayama Ks-band upper-limit
  46. GRB 151021A: MITSuME Okayama Ks-band upper-limit
  47. GRB 151021A: Swift-XRT refined Analysis
  48. GRB 151004A: Swift-XRT follow-up observations
  49. GRB 151006A: MITSuME Okayama Ks-band upper-limit
  50. GRB 151006A: Swift-XRT refined Analysis
  51. Trigger 657564 / GRB 151004A: Swift BAT and XRT refined analysis
  52. Swift Trigger 657564: XRT prompt analysis
  53. GRB 151001B: Swift-XRT refined Analysis
  54. GRB 151001A: Swift-XRT refined Analysis
  55. GRB 150925A: Swift-XRT refined Analysis
  56. LIGO/Virgo G184098: SkyMapper observations
  57. LIGO/Virgo G184098: Swift follow-up observations
  58. GRB 150915A: Swift-XRT refined Analysis
  59. GRB150915A : IRSF NIR upper limits
  60. GRB 150907A: Swift-XRT afterglow detection
  61. GRB 150912A: Swift-XRT and UVOT observations
  62. GRB 150911A: Swift-XRT refined Analysis
  63. GRB150911A MITSuME Okayama Ks-band upper-limit
  64. GRB 150910A: MITSuME Okayama Ks-band Observation
  65. GRB 150910A: Swift-XRT refined Analysis
  66. GRB 150910A: Swift/UVOT Detection of a Brightening Afterglow
  67. GRB 150907B: Swift-XRT refined Analysis
  68. GRB 150907A: Swift-XRT observations
  69. GRB 150902A: Swift-XRT afterglow detection
  70. GRB 150902A: Swift-XRT observations
  71. GRB 150821A: Flattening in the UVOT light curve
  72. GRB 150831B: Swift-XRT refined Analysis
  73. GRB 150831A: Swift-XRT refined Analysis
  74. GRB 150821A: Swift-XRT refined Analysis
  75. GRB 150819A: Swift-XRT refined Analysis
  76. GRB 150818A: Swift-XRT update, correction to GCN 18162
  77. GRB 150818A: Swift-XRT refined Analysis
  78. GRB 150817A: Swift-XRT refined Analysis
  79. GRB 150811A: KAIT Refined Analysis
  80. GRB 150811A: Swift-XRT refined Analysis
  81. GRB 150727A: IRSF NIR observation
  82. GRB 150801A: Swift-XRT observations
  83. GRB 150801B: Swift-XRT refined Analysis
  84. GRB 150724B: Swift-XRT afterglow detection
  85. GRB 150728A: Swift-XRT refined Analysis
  86. GRB 150727A: Swift-XRT refined Analysis
  87. GRB 150724B: Swift-XRT observations
  88. Correction to GCN 18059: Parameterisation of Swift-XRT light curve
  89. GRB 150724A: Swift-XRT refined Analysis
  90. GRB 150722A: Swift-XRT refined Analysis
  91. GRB 150720A: Swift-XRT refined Analysis
  92. GRB 150716A: Swift-XRT refined Analysis
  93. GRB 150710B: Swift-XRT afterglow detection
  94. GRB 150710B: Swift-XRT and Swift-UVOT observations
  95. GRB 150711A: Swift-XRT refined Analysis
  96. Swift-XRT observations of GRB 150710A
  97. GRB 150702A: Swift-XRT observations
  98. GRB 150622A: Swift-XRT afterglow detection
  99. GRB 150627A: Swift-XRT afterglow detection
  100. GRB 150626B: Swift-XRT refined Analysis

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