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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"

38155 results found.

  1. EP251220a: Global MASTER-Net observations report
  2. SVOM GRB251220.98: Global MASTER-Net observations report
  3. GRB 251220B: Fermi GBM Final Real-time Localization
  4. GRB 251219A: SVOM/GRM observation of a short burst
  5. GRB 251219A: GECAM-B detection of a possible magnetar X-ray burst from SGR 1830-0645
  6. GRB 251220A: MAXI/GSC detection
  7. GRB 251215A: Swift-XRT afterglow detection
  8. SVOM GRB251219.11: Global MASTER-Net observations report
  9. IceCube Alert 251218.85: Global MASTER-Net observations report
  10. GRB 251214B: VIRT Optical Upper Limit
  11. Fermi trigger No 787736968: Global MASTER-Net observations report
  12. Fermi GRB 251217A: Global MASTER-Net observations report
  13. GRB 251217A: Fermi GBM Final Real-time Localization
  14. GRB 251215A: Swift/UVOT Upper LImits
  15. GRB 251215A: Fermi GBM Observation
  16. Fermi GRB 251216A: Global MASTER-Net observations report
  17. GRB 251202A/EP251202a: Koshka optical upper limit
  18. GRB 251214B: Mondy optical upper limit
  19. GRB 251215A: COLIBRÍ optical upper limit
  20. GRB 251216A: Fermi GBM Final Real-time Localization
  21. EP251214b: KAIT optical upper limit
  22. GRB 251215A: Swift-XRT observations
  23. Fermi GRB 251215A: Global MASTER-Net observations report
  24. GRB 251214B: 1.6m Mephisto observations with newly installed mosaic cameras
  25. GRB 251215A: Glowbug gamma-ray detection
  26. GRB 251214B: UAFO optical upper limit
  27. GRB 251214B: VLT/X-shooter observations
  28. GRB 251213A: GRID-10B observation
  29. GRB 251214B: Swift-BAT refined analysis
  30. GRB 251202A: radio detection with the VLA
  31. EP251214b: Global MASTER-Net observations report
  32. GRB 251214B: AbAO optical observations
  33. GRB 251214B: LCO detection of the optical counterpart
  34. GRB 251209A: GECAM-B observation of a long burst
  35. GRB 251214D: GECAM-B observation of a long burst
  36. GRB 251214B: Fermi GBM Observation
  37. GRB 251209A: Insight-HXMT/HE detection
  38. GRB 251215A: Swift ToO observations
  39. GRID detection of GRB 251213A
  40. GRB 251203B: AbAO optical observations
  41. GRB 251215A: Swift/BAT-GUANO arcminute localization of a burst
  42. GRB 251214B: GECAM-B observation of a long burst
  43. GRB 251214B: Swift-XRT refined Analysis
  44. GRB 251213A: SVOM/GRM observation
  45. EP251214a: KAIT optical upper limit
  46. GRB 251214D: AstroSat CZTI detection of a long burst
  47. GRB 251213A: AstroSat CZTI detection
  48. GRB 251214A: AstroSat CZTI detection
  49. GRB 251213A: GECAM-B detection
  50. GRB 251214B: Swift/UVOT Detection
  51. GRB 251215A: Fermi GBM Final Real-time Localization
  52. GRB 251214B: COLIBRÍ observations of the afterglow
  53. GRB 251214A: GECAM-B observation of a likely long burst
  54. GRB 251214B: 1.3m DFOT optical detection
  55. EP251214a: Global MASTER-Net observations report
  56. GRB 251214B: Enhanced Swift-XRT position
  57. GRB 251214B: Xinglong-2.16m optical observation
  58. GRB 251214C: Fermi GBM Final Localization
  59. GRB 251214B : MASTER optical afterglow detection
  60. Fermi trigger No 787396657: Global MASTER-Net observations report
  61. GRB 251214B: SVOM/C-GFT optical observations
  62. EP251214a: COLIBRÍ optical upper limit
  63. Swift GRB 251214B: Global MASTER-Net observations report
  64. GRB 251214B: Swift detection of a burst with an optical counterpart
  65. GRB 251214B: Fermi GBM Final Real-time Localization
  66. EP251214a: EP-WXT detection of an X-ray transient possibly associated with GRB 251214A
  67. Fermi GRB 251214A: Global MASTER-Net observations report
  68. GRB 251214A: Fermi GBM Final Real-time Localization
  69. EP251212a: Global MASTER-Net observations report
  70. EP251212a: KAIT optical upper limit
  71. EP251212a / GRB 251212A: AstroSat CZTI detection
  72. GRB 251211B: AstroSat CZTI detection
  73. IceCube-251210A: No Candidate Transients from the Zwicky Transient Facility
  74. GRB 251209A: NuSTAR detection of prompt emission
  75. Fermi GRB 251211B: Global MASTER-Net observations report
  76. GRB 251211B: Fermi GBM Final Real-time Localization
  77. SVOM GRB251211.12: Global MASTER-Net observations report
  78. GRB 251211A: Fermi GBM Final Real-time Localization
  79. GRB 251209A: Fermi GBM observation
  80. GRB 251205A: 1.3m DFOT optical upper limit
  81. GRB 251209A: AstroSat CZTI detection
  82. IceCube Alert 251210.46: Global MASTER-Net observations report
  83. EP251124a: Mondy optical upper limit
  84. GRB 251129A/EP251129a: AbAO and Mondy optical observations
  85. EP251130a: Mondy and AbAO optical observations
  86. GRB 251208A: AstroSat CZTI detection
  87. Fermi GBM Sub-Threshold Detection of GRB 251205A
  88. GRB 251208A: Glowbug gamma-ray detection
  89. GRB 251208B: COLIBRÍ optical upper limits
  90. EP251118a / GRB 251118C: VLT/MUSE redshift confirmation
  91. GRB 251208C: GECAM-B observation of a short burst
  92. GRB 251208A: GECAM-B observation of a short burst
  93. Fermi GRB 251209A: Global MASTER-Net observations report
  94. Fermi GRB 251208C: Global MASTER-Net observations report
  95. GRB 251206A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  96. GRB 251208B: Swift-XRT afterglow detection
  97. GRB 251208D: LAST optical upper limit
  98. GRB 251209A: Fermi GBM Final Real-time Localization
  99. GRB 251208D: LCO analysis of the XRT sources
  100. GRB 251208B: Fermi GBM Observation

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