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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

12389 results found.

  1. GRB 151228B: AbAO optical upper limit
  2. GRB 160117A: Swift-XRT observations
  3. GRB 160117B: MASTER-Amur OT observations
  4. LIGO/Virgo G211117: Further Swift-XRT sources
  5. Konus-Wind observation of GRB 160111A
  6. GRB 160113A: Swift-XRT observations
  7. Konus-Wind observation of GRB 160107A
  8. GRB 160104A: Swift/UVOT Detection
  9. LIGO/Virgo G211117: Swift observations of PS15dpn
  10. GRB 160107A: MAXI/GSC detection
  11. Konus-Wind observation of GRB 160101A
  12. Konus-Wind observation of GRB 151225A
  13. LIGO/Virgo G211117: Further Swift-XRT sources
  14. GRB 160104A: Mini-GWAC upper limit during prompt emission phase
  15. GRB 160104A: GWAC upper limit during prompt emission phase
  16. GRB 160104A: MITSuME Okayama upper limits
  17. GRB 160104A: MASTER early OT detection
  18. GRB 160104A: MITSuME Okayama Ks-band upper-limit
  19. GRB 160104B: MAXI/GSC detection
  20. GRB 160102A: Swift-XRT observations
  21. GRB 160101A: MITSuME Akeno optical upper limits
  22. GRB 160102A: MAXI/GSC detection
  23. GRB 160101A: Swift/UVOT Detection
  24. GRB 160101A: MAXI/GSC detection
  25. LIGO/Virgo G211117: MAXI/GSC observations
  26. LIGO/Virgo G211117: INAF TNG follow-up of MASTER OT J020906.21+013800.1
  27. GRB 151228A: Correction to GCN 18770
  28. GRB 151228B: Swift/UVOT Detection
  29. GRB 151229A: MITSuME Akeno optical upper limits
  30. GRB 151229A: MITSuME Okayama upper limits
  31. GRB 151228B: MITSuME Akeno optical upper limits
  32. GRB 151229A: Swift/UVOT observations
  33. LIGO/Virgo G211117: Further Swift-XRT sources
  34. GRB 151228A: MITSuME Akeno optical upper limits
  35. GRB 151229A: Swift detection of a short burst
  36. LIGO/Virgo G211117: Optical follow-up with Kanata telescope
  37. LIGO/Virgo G211117: MASTER Observations and Inspection + OT
  38. LIGO/Virgo G211117: Further Swift-XRT sources
  39. GRB 151212A iTelescope observation
  40. GRB151215A: Continued P60 Observations
  41. GRB 151216A: MAXI/GSC detection
  42. GRB 151215A: MITSuME Akeno optical upper limits
  43. GRB151215A: Swift/UVOT detection
  44. GRB 151215A: Swift detection of a burst
  45. GRB151212A: Swift/UVOT observations
  46. GRB 151212A: GROND Optical Afterglow Candidate
  47. GRB 151212A: MAXI/GSC detection
  48. GRB 151210A: Swift/UVOT Upper Limits
  49. GRB 151205A: Khureltogot upper limit
  50. GRB 151205B: Deep GROND Upper limits
  51. GRB 130831A: MASTER early OT detection and LC
  52. GRB 151205B: further Swift-XRT observations
  53. GRB 151205C: Swift-XRT observations
  54. GRB 151205C: MAXI/GSC detection
  55. GRB 151205B: MASTER-NET early optical observations
  56. GRB 151205A: Garching Telescope Upper Limit
  57. GRB151205B: Initial UVOT observations
  58. GRB 151205A: Swift/UVOT Upper Limits
  59. GRB 151205A: Swift detection of a burst
  60. GRB 151127A iTelescope observation
  61. GRB 151122A: Further Swift-XRT observations, no afterglow detected.
  62. GRB 151127A: Swift/UVOT Upper Limits
  63. GRB 151127A: GROND K-band upper limit
  64. GRB 151127A: LCOGT-SSO optical upper limits
  65. GRB 151118A iTelescope observation
  66. GRB 151122A: Swift/UVOT Observations
  67. GRB 151122A: Swift-XRT observations
  68. Swift Trigger 664610 is not astrophysical
  69. Swift Trigger 664610: is unlikely a GRB
  70. GRB 151118A: MITSuME Akeno optical upper limits
  71. GRB 151118A: AAO optical upper limit
  72. GRB 151118A: Swift/UVOT Upper Limits
  73. GRB GRB 151118A: MASTER-NET optical observations
  74. GRB 151114A: Swift/UVOT Detection
  75. GRB 151112A: Swift/UVOT Upper Limits
  76. GRB 151112A: MAXI/GSC detection
  77. GRB 151111A: Swift/UVOT upper limits
  78. GRB 151111A: Swift detection of a burst
  79. GRB 151107B: MASTER-NET OT detection inside the FERMI error box
  80. GRB 151107A: Further investigation of the source nature
  81. LIGO/Virgo G194575: Swift observations if iPTF15dld
  82. GRB 151107A: MASTER-NET optical observations
  83. LIGO/Virgo G194575: MAXI/GSC further analysis
  84. GRB 151031A: MITSuME Akeno optical upper limits
  85. GRB 151031A: GROND observation
  86. GRB 151031A
  87. GRB 151031A: Swift/UVOT Detection
  88. GRB 151027B: RATIR Late-Time Upper Limits
  89. GRB 151029A: MITSuME Ishigakijima upper limits
  90. GRB 151029A: Swift/UVOT Detection
  91. GRB 151027A: MAXI/GSC detection
  92. GRB 151029A VLT/X-shooter redshift
  93. GRB 151029A: GROND afterglow observations
  94. GRB 151027B: Swift/UVOT Upper Limits
  95. Konus-Wind observation of GRB 151027A
  96. GRB 151027B: MASTER-NET early OT detection
  97. GRB 151027B: Swift detection of its 1000-th burst
  98. LIGO/Virgo G194575: MASTER Optical Inspection
  99. LIGO/Virgo G194575: Swift observations of LSQ15bjb
  100. LIGO/Virgo G194575: GROND multi-color observations

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