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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"

19718 results found.

  1. GRB 220711B, GROND observations
  2. GRB 220711B: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  3. GRB 220711B: GIT optical upper limits
  4. GRB 220712B: NOT optical afterglow confirmation
  5. GRB 220710A: Swift ToO observations
  6. IPN triangulation of GRB 220711C (short)
  7. GRB 220711B: Swift-XRT refined Analysis
  8. GRB 220711B: Swift/UVOT Upper Limits
  9. GRB 220711B: Enhanced Swift-XRT position
  10. GRB 220711B: Fermi GBM Detection
  11. GRB 220711B: NOT optical observations
  12. GRB 220711B: LCO Optical Upper Limits
  13. GRB 220711B: Swift detection of a burst
  14. GRB 220708B: GIT optical upper limits
  15. GRB 220708B: T193-OHP optical upper limit
  16. GRB 220708B: CALET Gamma-Ray Burst Monitor detection
  17. GRB 220708B: Nanshan/NEXT optical upper limits
  18. GRB 220708A: Swift/UVOT Upper Limits
  19. GRB 220706A : NICER detection of re-brightening 1 day after the Swift trigger
  20. GRB 220706A: Swift/UVOT Upper Limits
  21. GRB 220708A: Enhanced Swift-XRT position
  22. GRB 220708B: Swift ToO observations
  23. GRB 220708A: Swift-XRT observations
  24. GRB 220706A: LCO Optical Upper Limits
  25. GRB 220706A: Swift-XRT refined Analysis
  26. GRB 220706A, GROND observations
  27. GRB 220706A: Optical observations from NOT
  28. GRB 220706A: Nanshan/NEXT optical upper limits
  29. GRB 220706A: Enhanced Swift-XRT position
  30. GRB 220706A: Zadko observatory - Gingin optical observations
  31. GRB 220706A: Swift detection of a burst
  32. GRB 220701A: Swift-BAT refined analysis
  33. GRB220408A: VIRT Optical Upper Limit
  34. GRB220412A: VIRT Optical Upper Limit
  35. GRB220701A: VIRT Optical Upper Limit
  36. GRB 220701A: MITSuME Akeno optical upper limits
  37. Alert from the HAWC Burst Monitor HAWC-220702A
  38. GRB 220701A: COATLI Optical Upper Limit
  39. GRB 220701A: AbAO optical upper limit
  40. GRB 220701A: Keck/LRIS Optical Upper Limit
  41. GRB 220701A: LCO Optical Upper Limits
  42. GRB 220701A: Swift/UVOT Upper Limits
  43. GRB 220701A: Enhanced Swift-XRT position
  44. GRB 220701A: Swift detection of a burst
  45. Fermi-LAT Gamma-ray Observations of IceCube-220629A
  46. GRB 220627A, GROND observations
  47. GRB 220627A: Swift/UVOT Upper Limits
  48. Fermi-LAT Gamma-ray Observations of IceCube-220627A
  49. IceCube-220629A: No significant detection in HAWC
  50. IceCube-220627A: No significant detection in HAWC
  51. GRB 220627A: Swift-XRT afterglow detection
  52. GRB 220627A: VLT MUSE redshift
  53. GRB 220627A: MeerLICHT candidate optical afterglow
  54. Fermi-LAT Gamma-ray Observations of IceCube-220624A and and detection of a new gamma-ray source, Fermi J1458.0+4119
  55. GRB 220627A: Swift ToO observations
  56. GRB 220627A: MeerLICHT detection of two afterglow candidates
  57. IceCube-220624A: No significant detection in HAWC
  58. GRB 220623A: GIT optical upper limits.
  59. GRB 220623A: T193-OHP optical upper limit
  60. GRB 220624A: Fermi GBM Detection
  61. IPN triangulation of GRB 220624A
  62. GRB 220624A: AGILE/GRID analysis
  63. GRB 220623A: AbAO optical upper limit
  64. GRB 220623A: NOT optical observations
  65. GRB 220623A: Swift/UVOT Upper Limits
  66. GRB 220623A: Enhanced Swift-XRT position
  67. GRB 220623A: AstroSat CZTI detection
  68. GRB 220623A: iTelescope optical upper limit
  69. GRB 220623A: Swift-XRT observations
  70. GRB 220618A: Fermi GBM detection
  71. GRB 220618A: iTelescope T-19 upper limit
  72. GRB 220617A: TNG optical observations
  73. GRB 220618A: Swift/UVOT Upper Limits
  74. GRB 220618A: Enhanced Swift-XRT position
  75. GRB 220618A: Swift detection of a burst
  76. GRB 220617B: Swift ToO observations
  77. GRB 220611A: Gemini Ks counterpart detection
  78. GRB 220611A: Swift/UVOT Upper Limits
  79. GRB 220610B: AstroSat CZTI detection
  80. GRB 220611A: Enhanced Swift-XRT position
  81. GRB 220611A: Swift detection of a burst
  82. GRB 220608A: Fermi GBM Final Real-time Localization
  83. GRB 220606B: Gemini South Optical Observations
  84. GRB 220527A: A BdHN I with a clear UPE phase
  85. GRB 220606B: Swift ToO observations
  86. GRB 220527A: MITSuME Akeno continued optical observation
  87. GRB 220527A: Lick 3m Optical Observations
  88. IPN triangulation of GRB 220528A (short)
  89. GRB 220527A: REM optical/NIR observations
  90. GRB 220527A: MeerLICHT afterglow observations
  91. GRB 220527A: NOT optical photometry and spectroscopic redshift
  92. GRB 220527A: MITSuME Akeno optical observation
  93. GRB 220527A: Swift-XRT afterglow detection
  94. GRB 220527A: Swift ToO observations
  95. Fermi-LAT Gamma-ray Observations of IceCube-220524A
  96. IPN triangulation of GRB 220524A
  97. GRB 220521A: MITSuME Akeno optical upper limits
  98. GRB 220521A: REM optical/NIR upper limits
  99. GRB 220521A: RATIR Optical and NIR Observations
  100. GRB 220521A: Swift/UVOT Upper Limits

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