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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.

"200205A/SWIFT J0840.7-3516" does not adhere to advanced search syntax. Please refer to the documentation and try again.
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"

19598 results found.

  1. GRB 210410A: A twin of short GRB 090510 with complementary observations
  2. GRB 210410A: Swift/UVOT Upper Limits (revision)
  3. GRB 210411C: Swift/UVOT Detection
  4. GRB 210411C: Swift-BAT refined analysis
  5. GRB 210411C: Chilescope optical observations
  6. GRB 210411C: Swift-XRT refined Analysis
  7. Swift GRB 210411C: Global MASTER-Net observations report
  8. GRB 210411C: BOOTES-4/MET optical upper limit
  9. GRB 210411C: LCO Optical Afterglow Candidate
  10. GRB 210411C: Enhanced Swift-XRT position
  11. GRB 210406A: 10.4m GTC follow-up observation
  12. Konus-Wind detection of GRB 210410A
  13. GRB 210411C: Swift detection of a burst with an optical counterpart
  14. GRB 210410A: Swift-BAT refined analysis
  15. GRB 210410A: Swift-XRT refined Analysis
  16. GRB 210410A: Fermi GBM detection
  17. GRB 210410A: Swift/UVOT Upper Limits
  18. GRB 210406A: Swift-XRT observations
  19. GRB 210410A: RATIR Optical and NIR Observations
  20. GRB 210410A: AGILE detection of a burst
  21. GRB 210410A: Fermi-LAT detection
  22. GRB210410A: Candidate optical afterglow by Ondrejov D50
  23. GRB 210410A: Swift XRT localization
  24. Swift Triggers 1042031 and 1042032 are not astrophysical events
  25. GRB 210406A: Swift ToO observations
  26. GRB 210402A: MASTER prompt and follow up optical observation
  27. GRB 210402A: Swift/UVOT Upper Limits
  28. GRB 210402A: Fermi GBM detection
  29. GRB 210402A: Swift-BAT refined analysis
  30. GRB 210207B: Prompt and very late time observations with HCT.
  31. GRB 210402A: NOT optical afterglow candidate
  32. GRB 210402A: BOOTES-network early optical upper limit
  33. GRB 210403A: Swift-BAT refined analysis
  34. GRB 210402A: LBT observations
  35. GRB 210402A: DDOTI Upper Limits
  36. Swift GRB210403.35: Global MASTER-Net observations report
  37. GRB 210402A: Swift-XRT refined Analysis
  38. GRB 210403A: Swift detection of a burst
  39. GRB 210402A: Montarrenti Observatory upper limit
  40. GRB 210402A: Swift detection of a burst
  41. Swift GRB210402.92: Global MASTER-Net observations report
  42. GRB 210323A: Insight-HXMT/HE detection
  43. GRB 210321A: OSN Upper Limit
  44. GRB 210323A: MASTER optical observation
  45. GRB 210323A: Swift-BAT refined analysis
  46. GRB 210323A: Gemini-North Optical Source Detection
  47. Short GRB 210323A: GTC Observations
  48. GRB 210323B: Swift ToO observations
  49. Konus-Wind detection of GRB 210323A (short)
  50. GRB 210323A: Swift/UVOT Upper Limits
  51. GRB 210323A: Kitab optical upper limit
  52. GRB 210323A: Fermi GBM detection
  53. GRB 210318A: Swift/UVOT Upper Limits
  54. GRB 210323A: Swift-XRT refined Analysis
  55. GRB 210323A: Enhanced Swift-XRT position
  56. Swift GRB 210323A: Global MASTER-Net observations report
  57. GRB 210323B: Swift/BAT-GUANO detection and possible arcminute localization
  58. GRB 210323A: Swift detection of a short burst
  59. GRB 210321A: Swift/UVOT Detection
  60. Konus-Wind detection of GRB 210321A
  61. GRB 210318B: Swift/UVOT Upper Limits
  62. GRB 210321A: Swift-BAT refined analysis
  63. IceCube 135113_19489408.amon: Swift-XRT observations
  64. GRB 210321A: Swift-XRT refined Analysis
  65. GRB 210321A: NOT optical afterglow detection and redshift limit
  66. GRB 210321A: MASTER optical observation
  67. GRB 210321A: Enhanced Swift-XRT position
  68. GRB 210321A: DDOTI Afterglow Confirmation
  69. GRB 210321A: Swift/UVOT Detection
  70. GRB 210321A: Swift-XRT observations
  71. GRB 210321A: Swift detection of a burst
  72. GRB 210318B: MITSuME Okayama optical upper limits
  73. GRB 210318A: Swift-BAT refined analysis
  74. GRB 210318A: Swift-XRT refined Analysis
  75. GRB 210318A: Enhanced Swift-XRT position
  76. Swift GRB210318.13: Global MASTER-Net observations report
  77. GRB 210318B: Fermi GBM detection
  78. GRB 210318B: Swift-BAT refined analysis
  79. Swift GRB 210318A: Global MASTER-Net observations report
  80. Konus-Wind detection of GRB 210318B
  81. GRB210318B: Swift detection of a burst
  82. GRB 210318A: Swift detection of a burst
  83. GRB 210306A: GIT optical follow-up
  84. GRB 210226A: GIT optical upper limit
  85. GRB 210306A: HCT optical upper limit
  86. Konus-Wind detection of GRB 210308A
  87. Konus-Wind detection of GRB 210306A
  88. Konus-Wind detection of GRB 210305A
  89. GRB 210306A: Early Spectroscopy of the Optical Afterglow
  90. GRB 210306B: Fermi GBM detection
  91. GRB 210306A: Swift/UVOT Detection
  92. GRB 210308A: Swift-BAT refined analysis
  93. GRB 210307A: Swift-BAT refined analysis
  94. GRB 210308A: Swift/UVOT Detection
  95. GRB 210307A: Swift/UVOT Upper Limits
  96. GRB 210305A: Fermi GBM observation
  97. Swift GRB 210308A: Global MASTER-Net observations report
  98. GRB 210308A: Fermi GBM detection
  99. GRB 210305A: Swift-XRT refined Analysis
  100. GRB 210307A: Swift-XRT refined Analysis

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