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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"

32720 results found.

  1. GRB 251219A: SVOM/GRM observation of a short burst
  2. Fermi-LAT Gamma-ray Observations of IceCube-251218A
  3. IceCube-251218A: Upper limits from a search for additional neutrino events in IceCube
  4. IceCube-251218A: COLIBRÍ optical upper limits
  5. GRB 251214B: VIRT Optical Upper Limit
  6. Fermi GRB 251217A: Global MASTER-Net observations report
  7. GRB 251215A: Swift/UVOT Upper LImits
  8. GRB 251215A: Fermi GBM Observation
  9. Fermi GRB 251216A: Global MASTER-Net observations report
  10. GRB 251202A/EP251202a: Koshka optical upper limit
  11. GRB 251214B: Mondy optical upper limit
  12. GRB 251215A: COLIBRÍ optical upper limit
  13. EP251214b: KAIT optical upper limit
  14. Fermi GRB 251215A: Global MASTER-Net observations report
  15. EP251214a: Optical upper limit with Kinder observations
  16. GRB 251214B: 1.6m Mephisto observations with newly installed mosaic cameras
  17. GRB 251215A: Glowbug gamma-ray detection
  18. GRB 251214B: UAFO optical upper limit
  19. GRB 251214B: VLT/X-shooter observations
  20. GRB 251213A: GRID-10B observation
  21. GRB 251214B: Swift-BAT refined analysis
  22. GRB 251202A: radio detection with the VLA
  23. EP251214b: Global MASTER-Net observations report
  24. EP251214b : Einstein Probe detection of a fast X-ray transient
  25. EP251214b : Einstein Probe detection of a fast X-ray transient
  26. GRB 251214B: AbAO optical observations
  27. GRB 251214B: LCO detection of the optical counterpart
  28. GRB 251209A: GECAM-B observation of a long burst
  29. GRB 251214D: GECAM-B observation of a long burst
  30. GRB 251214B: Fermi GBM Observation
  31. GRB 251209A: Insight-HXMT/HE detection
  32. GRB 251215A: Swift ToO observations
  33. EP251214b (EP trigger 01709250023): LCO optical limits
  34. GRID detection of GRB 251213A
  35. GRB 251203B: AbAO optical observations
  36. GRB 251215A: Swift/BAT-GUANO arcminute localization of a burst
  37. GRB 251214B: GECAM-B observation of a long burst
  38. GRB 251213A: SVOM/GRM observation
  39. EP251214a: KAIT optical upper limit
  40. GRB 251213A: AstroSat CZTI detection
  41. GRB 251214A: AstroSat CZTI detection
  42. GRB 251214B: Swift/UVOT Detection
  43. GRB 251214B: COLIBRÍ observations of the afterglow
  44. EP251214a: EP-FXT non-detection and upper limit
  45. GRB 251214A: GECAM-B observation of a likely long burst
  46. GRB 251214B: 1.3m DFOT optical detection
  47. EP251214a: Global MASTER-Net observations report
  48. GRB 251214B: Xinglong-2.16m optical observation
  49. GRB 251214B : MASTER optical afterglow detection
  50. GRB 251214B: SVOM/C-GFT optical observations
  51. EP251214a: COLIBRÍ optical upper limit
  52. Swift GRB 251214B: Global MASTER-Net observations report
  53. EP251214a: EP-WXT detection of an X-ray transient possibly associated with GRB 251214A
  54. Fermi GRB 251214A: Global MASTER-Net observations report
  55. EP251212a: Global MASTER-Net observations report
  56. EP251212a: KAIT optical upper limit
  57. EP251212a / GRB 251212A: AstroSat CZTI detection
  58. EP251212a: EP-FXT follow-up observation
  59. GRB 251211B: AstroSat CZTI detection
  60. IceCube-251210A: No Candidate Transients from the Zwicky Transient Facility
  61. GRB 251209A: NuSTAR detection of prompt emission
  62. EP251212a : COLIBRÍ optical upper limit
  63. EP251212a: Einstein Probe detection of an X-ray transient
  64. Fermi-LAT Gamma-ray Observations of IceCube-251210A
  65. IceCube-251210A: Upper limits from a search for additional neutrino events in IceCube
  66. Fermi GRB 251211B: Global MASTER-Net observations report
  67. IceCube-251210A: DDOTI Optical Upper Limit
  68. GRB 251209A: Fermi GBM observation
  69. GRB 251205A: 1.3m DFOT optical upper limit
  70. GRB 251209A: AstroSat CZTI detection
  71. EP251124a: Mondy optical upper limit
  72. GRB 251129A/EP251129a: AbAO and Mondy optical observations
  73. EP251130a: Mondy and AbAO optical observations
  74. GRB 251208A: AstroSat CZTI detection
  75. Fermi GBM Sub-Threshold Detection of GRB 251205A
  76. GRB 251208A: Glowbug gamma-ray detection
  77. GRB 251208B: COLIBRÍ optical upper limits
  78. EP251118a / GRB 251118C: VLT/MUSE redshift confirmation
  79. GRB 251208C: GECAM-B observation of a short burst
  80. GRB 251208A: GECAM-B observation of a short burst
  81. Fermi GRB 251209A: Global MASTER-Net observations report
  82. Fermi GRB 251208C: Global MASTER-Net observations report
  83. GRB 251206A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  84. GRB 251208B: Swift-XRT afterglow detection
  85. GRB 251208D: LAST optical upper limit
  86. GRB 251208D: LCO analysis of the XRT sources
  87. GRB 251208B: Fermi GBM Observation
  88. GRB 251208B: GROWTH-India Telescope optical upper limits
  89. GRB 251205A: J-band detection with WINTER
  90. GRB 251208D: Swift-XRT observations
  91. GRB 251208A: SVOM/GRM observation of a short burst
  92. GRB 251208C: SVOM/GRM observation of a short burst
  93. GRB 251129A: e-MERLIN C-band observations
  94. GRB 251205A: Liverpool Telescope further optical follow-up observations
  95. GRB 251208D: LCO optical upper limits
  96. GRB 251208B: Swift ToO observations
  97. GRB 251208B: Fermi-LAT detection
  98. GRB 251208B: Swift/BAT-GUANO arcminute localization of a burst
  99. GRB 251208D: SVOM possible detection of a faint burst
  100. GRB 251205A : MITSuME Akeno optical afterglow candidate detection

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