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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"

22103 results found.

  1. Fermi trigger No 680782656: Global MASTER-Net observations report
  2. Fermi GRB 220728A: Global MASTER-Net observations report
  3. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-220728A
  4. Fermi trigger No 680421061: Global MASTER-Net observations report
  5. Fermi GRB 220724A: Global MASTER-Net observations report
  6. Fermi GRB 220721A: Global MASTER-Net observations report
  7. GRB220714B: UVOT detections
  8. GRB 220715B: Swift/UVOT Upper Limits
  9. Swift GRB 220715B: Global MASTER-Net observations report
  10. GRB 220714B: LCO Optical Observations
  11. GRB 220710A: Swift/UVOT Upper Limits
  12. Retraction of GRB 220711B: 10.4 m GTC(+EMIR) observations (GCN 32387)
  13. GRB 220711B: 10.4 m GTC(+EMIR) observations
  14. GRB 220711B: 10.4 m GTC(+EMIR) observations
  15. GRB 220710A: Swift-XRT afterglow detection
  16. GRB 220711C: Swift/BAT-GUANO detection outside the coded FOV
  17. GRB 220711B, GROND observations
  18. GRB 220711B: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  19. GRB 220711B: GIT optical upper limits
  20. Fermi trigger No 679248723: Global MASTER-Net observations report
  21. Fermi GRB 220711B: Global MASTER-Net observations report
  22. GRB 220712B: NOT optical afterglow confirmation
  23. GRB 220710A: Swift ToO observations
  24. GRB 220710A: Swift/BAT-GUANO arcminute localization
  25. GRB 220711B: Swift/UVOT Upper Limits
  26. GRB 220711B: NOT optical observations
  27. GRB 220708B: GIT optical upper limits
  28. IceCube-220624A: Classification of AT2022nit as a type Ia supernova and AT2021bei as an AGN
  29. GRB 220708A: Swift/UVOT Upper Limits
  30. GRB 220706A : NICER detection of re-brightening 1 day after the Swift trigger
  31. GRB 220706A: Swift/UVOT Upper Limits
  32. GRB 220708B: Swift-XRT afterglow detection
  33. GRB 220708B: Swift ToO observations
  34. GRB 220708B: Swift/BAT-GUANO arcminute localization
  35. GRB 220708A: Swift-XRT observations
  36. GRB 220627A: ATCA detection of radio counterpart
  37. GRB 220706A, GROND observations
  38. GRB 220706A: Optical observations from NOT
  39. GRB 220706A: MAXI/GSC detection 84 minutes after the Swift Trigger
  40. MAXI GRB220706.73: Global MASTER-Net observations report
  41. Swift GRB 220706A: Global MASTER-Net observations report
  42. GRB 220706A: Zadko observatory - Gingin optical observations
  43. Fermi trigger No 678635286: Global MASTER-Net observations report
  44. Alert from the HAWC Burst Monitor HAWC-220702A
  45. GRB 220701A: Swift/UVOT Upper Limits
  46. GRB 220701A: Lowell Discovery Telescope Optical Observations
  47. GRB 200701A: KAIT Optical Upper Limit
  48. Fermi-LAT Gamma-ray Observations of IceCube-220629A
  49. GRB 220627A, GROND observations
  50. GRB 220627A: Swift/UVOT Upper Limits
  51. Fermi-LAT Gamma-ray Observations of IceCube-220627A
  52. IceCube Alert 220629.99: Global MASTER-Net observations report
  53. GRB 220627A: Swift-XRT afterglow detection
  54. IceCube-220624A: One Candidate Counterpart from Swift/XRT follow up observations
  55. GRB 220627A: VLT MUSE redshift
  56. Swift XRT observations of WISEA J145820.77+412101.9 / IceCube 220624A
  57. GRB 220627A: MeerLICHT candidate optical afterglow
  58. GRB 220627A: Swift/BAT-GUANO detection outside the coded FOV
  59. Konus-Wind detection of GRB 220624A
  60. Fermi-LAT Gamma-ray Observations of IceCube-220624A and and detection of a new gamma-ray source, Fermi J1458.0+4119
  61. GRB 220627A: Swift ToO observations
  62. Fermi trigger No 678058621: Global MASTER-Net observations report
  63. GRB 220627A: MeerLICHT detection of two afterglow candidates
  64. Fermi GRB 220627A: Global MASTER-Net observations report
  65. IceCube Alert 220627.74: Global MASTER-Net observations report
  66. GRB 220623A: GIT optical upper limits.
  67. IceCube-220624A: No Candidate Counterparts from the Zwicky Transient Facility
  68. Fermi GRB 220623B: Global MASTER-Net observations report
  69. Fermi GRB 220624A: Global MASTER-Net observations report
  70. IceCube Alert 220624.68: Global MASTER-Net observations report
  71. GRB 220624A: Swift/BAT-GUANO detection outside the coded FOV
  72. GRB 220611A: X-ray afterglow Chandra sub-arcsecond localization
  73. Konus-Wind detection of GRB 220623A
  74. GRB 220623A: NOT optical observations
  75. GRB 220623A: Swift/UVOT Upper Limits
  76. GRB 220623A: BOOTES-5/JGT optical afterglow detection
  77. Konus-Wind detection of GRB 220609B
  78. GRB 220623A: Swift-XRT observations
  79. Fermi trigger No 677597318: Global MASTER-Net observations report
  80. Fermi trigger No 677377371: Global MASTER-Net observations report
  81. Fermi GRB 220620B: Global MASTER-Net observations report
  82. Fermi GRB 220620A: Global MASTER-Net observations report
  83. Integral GRB220619.53: Global MASTER-Net observations report
  84. Swift GRB220620.02: Global MASTER-Net observations report
  85. GRB 220611A: Continued Gemini Infrared Observations
  86. GRB 220617A: TNG optical observations
  87. Fermi trigger No 677307509: Global MASTER-Net observations report
  88. Fermi trigger No 677236224: Global MASTER-Net observations report
  89. GRB 220611A optical counterpart
  90. GRB 220618A: Swift/UVOT Upper Limits
  91. GRB220611A: Gemini Optical Afterglow Confirmation
  92. GRB 220617A: Swift-XRT observations
  93. Swift GRB220618.38: Global MASTER-Net observations report
  94. GRB 220617B: Swift ToO observations
  95. Fermi GRB 220617A: Global MASTER-Net observations report
  96. GRB 220611A: Gemini Ks counterpart detection
  97. Fermi trigger No 677174940: Global MASTER-Net observations report
  98. Konus-Wind detection of GRB 220613A
  99. GRB 220611A: Gemini South Infrared Detection
  100. GRB 220611A: Swift/UVOT Upper Limits

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