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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

22198 results found.

  1. Fermi GRB 220721A: Global MASTER-Net observations report
  2. GRB220714B: UVOT detections
  3. GRB 220715B: Swift/UVOT Upper Limits
  4. Swift GRB 220715B: Global MASTER-Net observations report
  5. GRB 220714B: LCO Optical Observations
  6. GRB 220710A: Swift/UVOT Upper Limits
  7. Retraction of GRB 220711B: 10.4 m GTC(+EMIR) observations (GCN 32387)
  8. GRB 220711B: 10.4 m GTC(+EMIR) observations
  9. GRB 220711B: 10.4 m GTC(+EMIR) observations
  10. GRB 220710A: Swift-XRT afterglow detection
  11. GRB 220711C: Swift/BAT-GUANO detection outside the coded FOV
  12. GRB 220711B, GROND observations
  13. GRB 220711B: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  14. GRB 220711B: GIT optical upper limits
  15. Fermi trigger No 679248723: Global MASTER-Net observations report
  16. Fermi GRB 220711B: Global MASTER-Net observations report
  17. GRB 220712B: NOT optical afterglow confirmation
  18. GRB 220710A: Swift ToO observations
  19. GRB 220710A: Swift/BAT-GUANO arcminute localization
  20. GRB 220711B: Swift/UVOT Upper Limits
  21. GRB 220711B: NOT optical observations
  22. GRB 220708B: GIT optical upper limits
  23. IceCube-220624A: Classification of AT2022nit as a type Ia supernova and AT2021bei as an AGN
  24. GRB 220708A: Swift/UVOT Upper Limits
  25. GRB 220706A : NICER detection of re-brightening 1 day after the Swift trigger
  26. GRB 220706A: Swift/UVOT Upper Limits
  27. GRB 220708B: Swift-XRT afterglow detection
  28. GRB 220708B: Swift ToO observations
  29. GRB 220708B: Swift/BAT-GUANO arcminute localization
  30. GRB 220708A: Swift-XRT observations
  31. GRB 220627A: ATCA detection of radio counterpart
  32. GRB 220706A, GROND observations
  33. GRB 220706A: Optical observations from NOT
  34. GRB 220706A: MAXI/GSC detection 84 minutes after the Swift Trigger
  35. MAXI GRB220706.73: Global MASTER-Net observations report
  36. Swift GRB 220706A: Global MASTER-Net observations report
  37. GRB 220706A: Zadko observatory - Gingin optical observations
  38. Fermi trigger No 678635286: Global MASTER-Net observations report
  39. Alert from the HAWC Burst Monitor HAWC-220702A
  40. GRB 220701A: Swift/UVOT Upper Limits
  41. GRB 220701A: Lowell Discovery Telescope Optical Observations
  42. GRB 200701A: KAIT Optical Upper Limit
  43. Fermi-LAT Gamma-ray Observations of IceCube-220629A
  44. GRB 220627A, GROND observations
  45. GRB 220627A: Swift/UVOT Upper Limits
  46. Fermi-LAT Gamma-ray Observations of IceCube-220627A
  47. IceCube Alert 220629.99: Global MASTER-Net observations report
  48. GRB 220627A: Swift-XRT afterglow detection
  49. IceCube-220624A: One Candidate Counterpart from Swift/XRT follow up observations
  50. GRB 220627A: VLT MUSE redshift
  51. Swift XRT observations of WISEA J145820.77+412101.9 / IceCube 220624A
  52. GRB 220627A: MeerLICHT candidate optical afterglow
  53. GRB 220627A: Swift/BAT-GUANO detection outside the coded FOV
  54. Konus-Wind detection of GRB 220624A
  55. Fermi-LAT Gamma-ray Observations of IceCube-220624A and and detection of a new gamma-ray source, Fermi J1458.0+4119
  56. GRB 220627A: Swift ToO observations
  57. Fermi trigger No 678058621: Global MASTER-Net observations report
  58. GRB 220627A: MeerLICHT detection of two afterglow candidates
  59. Fermi GRB 220627A: Global MASTER-Net observations report
  60. IceCube Alert 220627.74: Global MASTER-Net observations report
  61. GRB 220623A: GIT optical upper limits.
  62. IceCube-220624A: No Candidate Counterparts from the Zwicky Transient Facility
  63. Fermi GRB 220623B: Global MASTER-Net observations report
  64. Fermi GRB 220624A: Global MASTER-Net observations report
  65. IceCube Alert 220624.68: Global MASTER-Net observations report
  66. GRB 220624A: Swift/BAT-GUANO detection outside the coded FOV
  67. GRB 220611A: X-ray afterglow Chandra sub-arcsecond localization
  68. Konus-Wind detection of GRB 220623A
  69. GRB 220623A: NOT optical observations
  70. GRB 220623A: Swift/UVOT Upper Limits
  71. GRB 220623A: BOOTES-5/JGT optical afterglow detection
  72. Konus-Wind detection of GRB 220609B
  73. GRB 220623A: Swift-XRT observations
  74. Fermi trigger No 677597318: Global MASTER-Net observations report
  75. Fermi trigger No 677377371: Global MASTER-Net observations report
  76. Fermi GRB 220620B: Global MASTER-Net observations report
  77. Fermi GRB 220620A: Global MASTER-Net observations report
  78. Integral GRB220619.53: Global MASTER-Net observations report
  79. Swift GRB220620.02: Global MASTER-Net observations report
  80. GRB 220611A: Continued Gemini Infrared Observations
  81. GRB 220617A: TNG optical observations
  82. Fermi trigger No 677307509: Global MASTER-Net observations report
  83. Fermi trigger No 677236224: Global MASTER-Net observations report
  84. GRB 220611A optical counterpart
  85. GRB 220618A: Swift/UVOT Upper Limits
  86. GRB220611A: Gemini Optical Afterglow Confirmation
  87. GRB 220617A: Swift-XRT observations
  88. Swift GRB220618.38: Global MASTER-Net observations report
  89. GRB 220617B: Swift ToO observations
  90. Fermi GRB 220617A: Global MASTER-Net observations report
  91. GRB 220611A: Gemini Ks counterpart detection
  92. Fermi trigger No 677174940: Global MASTER-Net observations report
  93. Konus-Wind detection of GRB 220613A
  94. GRB 220611A: Gemini South Infrared Detection
  95. GRB 220611A: Swift/UVOT Upper Limits
  96. Fermi trigger No 676909037: Global MASTER-Net observations report
  97. GRB 220612A: Swift/BAT-GUANO detection
  98. Swift GRB 220611A: Global MASTER-Net observations report
  99. Fermi GRB 220610A: Global MASTER-Net observations report
  100. Fermi trigger No 676537486: Global MASTER-Net observations report

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