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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"

21526 results found.

  1. GRB 220708B: GIT optical upper limits
  2. GRB 220708A: Swift-BAT refined analysis
  3. GRB 220708B: T193-OHP optical upper limit
  4. Konus-Wind detection of GRB 220708B
  5. GRB 220708B: CALET Gamma-Ray Burst Monitor detection
  6. GRB 220708B: Nanshan/NEXT optical upper limits
  7. GRB 220708A: Swift/UVOT Upper Limits
  8. GRB 220706A : NICER detection of re-brightening 1 day after the Swift trigger
  9. GRB 220708A: Swift-XRT refined Analysis
  10. GRB 220706A: Swift/UVOT Upper Limits
  11. GRB 220708B: Swift-XRT afterglow detection
  12. GRB 220708A: BOOTES-5/JGT early optical upper limit
  13. GRB 220706A: Swift-BAT refined analysis
  14. GRB 220708A: Enhanced Swift-XRT position
  15. GRB 220708B: Swift ToO observations
  16. GRB 220708B: Swift/BAT-GUANO arcminute localization
  17. GRB 220708A: Swift-XRT observations
  18. GRB 220708A: Swift detection of a burst
  19. GRB 220706A: LCO Optical Upper Limits
  20. GRB 220706A: Swift-XRT refined Analysis
  21. GRB 220706A, GROND observations
  22. GRB 220706A: Optical observations from NOT
  23. GRB 220706A: MAXI/GSC detection 84 minutes after the Swift Trigger
  24. GRB 220706A: Nanshan/NEXT optical upper limits
  25. GRB 220706A: Enhanced Swift-XRT position
  26. Swift GRB 220706A: Global MASTER-Net observations report
  27. GRB 220706A: Zadko observatory - Gingin optical observations
  28. GRB 220706A: Prompt enhanced Swift-XRT position
  29. GRB 220706A: Swift detection of a burst
  30. GRB 220701A: Swift-BAT refined analysis
  31. GRB220408A: VIRT Optical Upper Limit
  32. GRB220412A: VIRT Optical Upper Limit
  33. GRB220701A: VIRT Optical Upper Limit
  34. GRB 220701A: MITSuME Akeno optical upper limits
  35. GRB 220701A: COATLI Optical Upper Limit
  36. GRB 220701A: AbAO optical upper limit
  37. GRB 220627A: AstroSat CZTI detection
  38. GRB 220701A: Keck/LRIS Optical Upper Limit
  39. GRB 220701A: Swift-XRT refined Analysis
  40. GRB 220701A: LCO Optical Upper Limits
  41. GRB 220701A: BOOTES-5/JGT early optical upper limit
  42. GRB 220701A: Swift/UVOT Upper Limits
  43. GRB 220701A: Lowell Discovery Telescope Optical Observations
  44. GRB 220701A: Enhanced Swift-XRT position
  45. GRB 200701A: KAIT Optical Upper Limit
  46. GRB 220701A: Swift detection of a burst
  47. GRB 220627A: Swift/UVOT Upper Limits
  48. GRB 220627A: Swift-XRT afterglow detection
  49. Konus-Wind detection of GRB 220627A
  50. Trigger 1113743: Swift detection of MAXI J0655-013
  51. IceCube-220624A: One Candidate Counterpart from Swift/XRT follow up observations
  52. Swift XRT observations of WISEA J145820.77+412101.9 / IceCube 220624A
  53. GRB 220627A: MeerLICHT candidate optical afterglow
  54. GRB 220627A: Fermi GBM Detection of a possible Lensed or Ultra-long GRB
  55. GRB 220627A: Swift/BAT-GUANO detection outside the coded FOV
  56. Konus-Wind detection of GRB 220624A
  57. GRB 220627A: Swift ToO observations
  58. GRB 220627A: Fermi-LAT detection
  59. GRB 220623A: GIT optical upper limits.
  60. GRB 220624A: CALET Gamma-Ray Burst Monitor detection
  61. GRB 220623A: T193-OHP optical upper limit
  62. GRB 220624A: Fermi GBM Detection
  63. IPN triangulation of GRB 220624A
  64. GRB 220623A: Swift-BAT refined analysis
  65. GRB 220624A: Swift/BAT-GUANO detection outside the coded FOV
  66. GRB 220611A: X-ray afterglow Chandra sub-arcsecond localization
  67. Konus-Wind detection of GRB 220623A
  68. GRB 220623A: AbAO optical upper limit
  69. GRB 220623A: Swift-XRT refined Analysis
  70. GRB 220623A: NOT optical observations
  71. GRB 220623A: Swift/UVOT Upper Limits
  72. GRB 220623A: BOOTES-5/JGT optical afterglow detection
  73. GRB 220623A: Enhanced Swift-XRT position
  74. GRB 220623A: AGILE detection
  75. GRB 220623A: AstroSat CZTI detection
  76. GRB 220623A: iTelescope optical upper limit
  77. GRB 220623A: Swift-XRT observations
  78. GRB 220623A: Swift detection of a burst
  79. GRB 220618A: Fermi GBM detection
  80. Swift Detection of MAXI J0655-013
  81. GRB 220618A: Swift-BAT refined analysis
  82. GRB 220618A: iTelescope T-19 upper limit
  83. Swift GRB220620.02: Global MASTER-Net observations report
  84. GRB 220611A: Continued Gemini Infrared Observations
  85. GRB 220617A: TNG optical observations
  86. Swift Trigger 1110865 is probably not an astrophysical event
  87. GRB 220618A: Swift-XRT refined Analysis
  88. IPN triangulation of GRB 220617A (short)
  89. GRB 220618A: BOOTES-5/JGT early optical upper limit
  90. GRB 220618A: Swift/UVOT Upper Limits
  91. GRB 220618A: Enhanced Swift-XRT position
  92. GRB 220617A: Swift-XRT observations
  93. GRB 220618A: Swift detection of a burst
  94. Swift GRB220618.38: Global MASTER-Net observations report
  95. GRB 220617A: Fermi-LAT detection
  96. GRB 220617B: Swift ToO observations
  97. GRB 220611A: Gemini South Infrared Detection
  98. GRB 220611A: Swift/UVOT Upper Limits
  99. GRB 220612A: CALET Gamma-Ray Burst Monitor detection
  100. GRB 220612A: Swift/BAT-GUANO detection

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