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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"

45605 results found.

  1. EP251214b: Global MASTER-Net observations report
  2. EP251214b : Einstein Probe detection of a fast X-ray transient
  3. EP251214b : Einstein Probe detection of a fast X-ray transient
  4. GRB 251214B: AbAO optical observations
  5. GRB 251214B: LCO detection of the optical counterpart
  6. GRB 251209A: GECAM-B observation of a long burst
  7. GRB 251214D: GECAM-B observation of a long burst
  8. GRB 251214B: Fermi GBM Observation
  9. GRB 251209A: Insight-HXMT/HE detection
  10. GRB 251215A: Swift ToO observations
  11. EP251214b (EP trigger 01709250023): LCO optical limits
  12. GRID detection of GRB 251213A
  13. GRB 251203B: AbAO optical observations
  14. GRB 251215A: Swift/BAT-GUANO arcminute localization of a burst
  15. GRB 251214B: GECAM-B observation of a long burst
  16. GRB 251214B: Swift-XRT refined Analysis
  17. GRB 251213A: SVOM/GRM observation
  18. EP251214a: KAIT optical upper limit
  19. GRB 251214D: AstroSat CZTI detection of a long burst
  20. GRB 251213A: AstroSat CZTI detection
  21. GRB 251214A: AstroSat CZTI detection
  22. GRB 251213A: GECAM-B detection
  23. GRB 251214B: Swift/UVOT Detection
  24. GRB 251215A: Fermi GBM Final Real-time Localization
  25. GRB 251214B: COLIBRÍ observations of the afterglow
  26. EP251214a: EP-FXT non-detection and upper limit
  27. GRB 251214A: GECAM-B observation of a likely long burst
  28. GRB 251214B: 1.3m DFOT optical detection
  29. EP251214a: Global MASTER-Net observations report
  30. GRB 251214B: Enhanced Swift-XRT position
  31. GRB 251214B: Xinglong-2.16m optical observation
  32. GRB 251214C: Fermi GBM Final Localization
  33. GRB 251214B : MASTER optical afterglow detection
  34. Fermi trigger No 787396657: Global MASTER-Net observations report
  35. GRB 251214B: SVOM/C-GFT optical observations
  36. EP251214a: COLIBRÍ optical upper limit
  37. Swift GRB 251214B: Global MASTER-Net observations report
  38. EP251214.305: COLIBRÍ optical upper limit
  39. GRB 251214B: Swift detection of a burst with an optical counterpart
  40. GRB 251214B: Fermi GBM Final Real-time Localization
  41. EP251214a: EP-WXT detection of an X-ray transient possibly associated with GRB 251214A
  42. Fermi GRB 251214A: Global MASTER-Net observations report
  43. GRB 251214A: Fermi GBM Final Real-time Localization
  44. EP251212a: Global MASTER-Net observations report
  45. EP251212a: KAIT optical upper limit
  46. EP251212a / GRB 251212A: AstroSat CZTI detection
  47. EP251212a: EP-FXT follow-up observation
  48. GRB 251211B: AstroSat CZTI detection
  49. IceCube-251210A: No Candidate Transients from the Zwicky Transient Facility
  50. GRB 251209A: NuSTAR detection of prompt emission
  51. EP251212a : COLIBRÍ optical upper limit
  52. EP251212a: Einstein Probe detection of an X-ray transient
  53. Fermi-LAT Gamma-ray Observations of IceCube-251210A
  54. IceCube-251210A: Upper limits from a search for additional neutrino events in IceCube
  55. Fermi GRB 251211B: Global MASTER-Net observations report
  56. GRB 251211B: Fermi GBM Final Real-time Localization
  57. IceCube-251210A: DDOTI Optical Upper Limit
  58. SVOM GRB251211.12: Global MASTER-Net observations report
  59. GRB 251211A: Fermi GBM Final Real-time Localization
  60. GRB 251209A: Fermi GBM observation
  61. GRB 251205A: 1.3m DFOT optical upper limit
  62. GRB 251209A: AstroSat CZTI detection
  63. IceCube Alert 251210.46: Global MASTER-Net observations report
  64. IceCube-251210A - IceCube observation of a high-energy neutrino candidate track-like event
  65. EP251124a: Mondy optical upper limit
  66. GRB 251129A/EP251129a: AbAO and Mondy optical observations
  67. EP251130a: Mondy and AbAO optical observations
  68. GRB 251208A: AstroSat CZTI detection
  69. Fermi GBM Sub-Threshold Detection of GRB 251205A
  70. GRB 251208A: Glowbug gamma-ray detection
  71. GRB 251208B: COLIBRÍ optical upper limits
  72. EP251118a / GRB 251118C: VLT/MUSE redshift confirmation
  73. GRB 251208C: GECAM-B observation of a short burst
  74. GRB 251208A: GECAM-B observation of a short burst
  75. Fermi GRB 251209A: Global MASTER-Net observations report
  76. Fermi GRB 251208C: Global MASTER-Net observations report
  77. GRB 251206A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  78. GRB 251208B: Swift-XRT afterglow detection
  79. GRB 251208D: LAST optical upper limit
  80. GRB 251209A: Fermi GBM Final Real-time Localization
  81. GRB 251208D: LCO analysis of the XRT sources
  82. GRB 251208B: Fermi GBM Observation
  83. GRB 251208B: GROWTH-India Telescope optical upper limits
  84. GRB 251205A: J-band detection with WINTER
  85. GRB 251208D: Swift-XRT observations
  86. GRB 251208A: SVOM/GRM observation of a short burst
  87. GRB 251208C: SVOM/GRM observation of a short burst
  88. GRB 251129A: e-MERLIN C-band observations
  89. LAT GRB251208.43: Global MASTER-Net observations report
  90. GRB 251205A: Liverpool Telescope further optical follow-up observations
  91. GRB 251208D: LCO optical upper limits
  92. SVOM GRB251208D: Global MASTER-Net observations report
  93. GRB 251208B: Swift ToO observations
  94. GRB 251208B: Fermi-LAT detection
  95. GRB 251208B: Swift/BAT-GUANO arcminute localization of a burst
  96. GRB 251208D: SVOM possible detection of a faint burst
  97. GRB 251206A: SVOM detection of a burst through offline search
  98. GRB 251208C: Fermi GBM Final Real-time Localization
  99. GRB 251205A : MITSuME Akeno optical afterglow candidate detection
  100. GRB 251208B: Fermi GBM Final Real-time Localization

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