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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"

39496 results found.

  1. Swift GRB 210226A: Global MASTER-Net observations report
  2. GRB 210218A: Swift-XRT confirmation of afterglow
  3. GRB 210226A: Burke-Gaffney Observatory optical upper limit
  4. GRB 210226A: Enhanced Swift-XRT position
  5. GRB 210226A: Ondrejov BART/SBT optical limit
  6. GRB 210222B: 1.3m DFOT Optical upper limit
  7. GRB 210226A: Swift detection of a burst
  8. GRB 210222B: REM observations of the optical/NIR afterglow
  9. Fermi trigger No 635922820: Global MASTER-Net observations report
  10. GRB 210222B: MITSuME Akeno optical upper limits
  11. Konus-Wind detection of GRB 210222A
  12. GRB 210222B: Zeiss-1000 of Koshka observatory, optical observations
  13. GRB 210222B: VIRT optical detection
  14. GRB 210222B: Swift-BAT refined analysis
  15. GRB 210222B: Swift-XRT refined Analysis
  16. GRB 210222B: Swift/UVOT Detection
  17. GRB 210222B: KAIT Optical Upper Limit
  18. GRB 210222B: FRAM-ORM afterglow detection
  19. GRB 210218A: Swift/UVOT observations
  20. GRB 210217A: Swift/UVOT Detection
  21. GRB 210222B: MASTER OT observation
  22. GRB 210222A: CALET Gamma-Ray Burst Monitor detection
  23. GRB 210222B: Redshift from FORS2/VLT
  24. GRB 210222B: NEXT early optical afterglow observations
  25. GRB 210222B: GOTO confirmation of afterglow detection (correction to GCN29548)
  26. GRB 210222B: Liverpool Telescope optical detection
  27. GRB 210222B: GOTO confirmation of afterglow detection
  28. GRB210222B: LCO Optical Afterglow Detection
  29. GRB210222B: BOOTES-1 optical afterglow detection
  30. GRB 210222B: Swift detection of a burst with an optical counterpart
  31. Swift GRB210222.94: Global MASTER-Net observations report
  32. GRB 210222A: MAXI/GSC detection
  33. GRB 210218A: Swift-XRT observations
  34. uGMRT radio detection of GRB 210204A
  35. GRB 210212A: Lowell Discovery Telescope observations
  36. GRB 210217A: 1.3m DFOT optical detection
  37. GRB 210217A: Swift-XRT refined Analysis
  38. GRB 210218A: Swift-BAT refined analysis
  39. Fermi GBM Sub-Threshold Detection of GRB 210217A
  40. GRB 210217A: Liverpool Telescope First Hour Observations
  41. GRB 210217A: Swift-BAT refined analysis
  42. GRB 210217A: KAIT Optical Observations
  43. GRB 210218A: MITSuME Akeno optical upper limits
  44. GRB 210218A： GWAC-F60A optical upper limit
  45. GRB 210218A: NEXT optical upper limit
  46. GRB 210218A: Swift detection of a burst
  47. ZTF21aakruew/AT2021cwd: GROND observations
  48. GRB 210212A: REM early-time optical/NIR upper limits
  49. GRB 210205A: observations with the 3.6m DOT, a potential dark burst?
  50. GRB 210217A: Enhanced Swift-XRT position
  51. Fermi/GBM observation of a burst from SGR 1830-0645
  52. GRB 210217A: NEXT early optical afterglow observations
  53. GRB 210212A: Mondy optical observations
  54. GRB 210217A: Swift detection of a burst with an optical counterpart
  55. GRB 210204A (ZTF21aagwbjr/AT2021buv): continued Assy and Mondy optical observations
  56. GRB 210208A: 1.3m DFOT Optical upper limit
  57. GRB 210210A: Konus-Wind detection and joint Konus-Wind + Swift-BAT spectral analysis
  58. Swift Trigger 1033144: Detection of SGR 1830-0645
  59. GRB 210211A: ePESSTO+ NTT optical observations
  60. Konus-Wind detection of GRB 210212B / ZTF21aakruew
  61. GRB 210212B: Swift ToO observations
  62. GRB 210212B (TF21aakruew/AT2021cwd): Assy optical observations
  63. IPN triangulation of GRB 210212B (consistent with ZTF21aakruew/AT2021cwd)
  64. GRB 210212A: 1.3m DFOT Optical upper limit
  65. GRB 210213B: Insight-HXMT/HE detection
  66. GRB 210212A: Gemini South optical observations
  67. Fermi GRB 210213A: Global MASTER-Net observations report
  68. IceCube Alert 210213.78: Global MASTER-Net observations report
  69. GRB 210213A: Fermi GBM Final Real-time Localization
  70. GRB 210210A: CAHA 2nd epoch and jet break confirmation
  71. Swift Trigger 1032350: Detection of SGR 1830-0645
  72. GRB 210204A (ZTF21aagwbjr/AT2021buv): continued CrAO and AbAO optical observations
  73. GRB 210212A: Possible host galaxy counterpart with the NOT
  74. Swift GRB 210212A: Global MASTER-Net observations report
  75. GRB 210212A: MITSuME Akeno optical upper limits
  76. GRB 210212A: Swift-XRT refined Analysis
  77. GRB 210212A: BOOTES-4/MET optical upper limit
  78. GRB 210212A: Swift/UVOT Upper Limits
  79. GRB 210212A: Swift-BAT refined analysis
  80. GRB 210204A: observations with the 3.6m Devasthal Optical Telescope and possible jet break
  81. GRB 210212A: Enhanced Swift-XRT position
  82. GRB 210210A : 1.3m DFOT optical observations
  83. GRB 210212A: Swift detection of a burst
  84. GRB 210207B: GECAM detection
  85. GRB 210211A: Swift/UVOT Detection
  86. GRB 210211A: Swift-XRT refined Analysis
  87. GRB 210211A: Swift-BAT refined analysis
  88. GRB 210211A: Fermi GBM observation
  89. GRB 210210A as a BdHN II
  90. GRB 210209A: Swift-BAT refined analysis
  91. GRB 210211A: Enhanced Swift-XRT position
  92. GRB 210211A: MASTER optical observation of REM OT
  93. GRB 210210A: CAHA detection and likely jet break
  94. GRB 210211A: REM optical/NIR afterglow detection
  95. Fermi-LAT Gamma-ray Observations of IceCube-210210A
  96. GRB 210211A: Swift detection of a burst
  97. Swift GRB210211.36: Global MASTER-Net observations report
  98. GRB 210211A: Fermi GBM Final Real-time Localization
  99. GRB 210210A: FRAM-ORM afterglow detection
  100. Fermi trigger No 634659312: Global MASTER-Net observations report

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