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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

19603 results found.

  1. GRB 260204A: SVOM/VT confirms fading of the optical afterglow
  2. GRB 260204A: Swift-XRT observations
  3. GRB 260204A: SVOM/VT optical candidate
  4. GRB 251230A: MeerLICHT afterglow detection
  5. GRB 260127A: GECAM-B observation
  6. GRB 260127B: AstroSat CZTI detection
  7. IPN triangulation of GRB 260121A
  8. GRB 260127A: Swift-BAT refined analysis
  9. GRB 260127B: Swift-XRT observations
  10. GRB 260127A: INASAN-Kislovodsk, SAO RAS, and Terskol K-800 optical observations
  11. GRB 260127A: Fermi GBM Observation
  12. GRB 260127A: COLIBRÍ optical observations
  13. GRB 260127B: Swift ToO observations
  14. GRB 260127A : MITSuME Akeno optical afterglow candidate detection
  15. GRB 260127A: Swift-XRT refined Analysis
  16. GRB 260127A: SVOM/C-GFT optical observations
  17. GRB 260127A: Enhanced Swift-XRT position
  18. GRB 260127A: Prompt enhanced Swift-XRT position
  19. Swift GRB 260127A: Global MASTER-Net observations report
  20. GRB 260127A: Swift detection of a burst
  21. GRB 260125A: Swift-XRT observations
  22. Konus-Wind detection of GRB 260120B
  23. GRB 260125A: Swift ToO observations
  24. GRB 260114A: SVOM/VT optical upper limits
  25. GRB 260122B: Swift-BAT refined analysis
  26. GRB 260120B: SVOM/GRM observation
  27. GRB 260120B: AstroSat CZTI detection
  28. GRB 260114A: Insight-HXMT/HE detection
  29. GRB 260122B: Swift detection of a burst
  30. Swift GRB260122.97: Global MASTER-Net observations report
  31. GRB 260120B: Swift-BAT refined analysis
  32. GRB 260120B: Swift-XRT refined Analysis
  33. GRB 260120B: Fermi GBM Observation
  34. GRB 260120B: Swift/UVOT Detection
  35. GRB 260120B: COLIBRÍ optical upper limits
  36. GRB 260120B: Enhanced Swift-XRT position
  37. GRB 260120B: SVOM/C-GFT optical counterpart detection
  38. GRB 260101A: 239Alferov CubeSat detection
  39. GRB 260120B: Swift detection of a burst
  40. Swift GRB260120B: Global MASTER-Net observations report
  41. GRB 260114A: Swift/UVOT Upper Limits
  42. Trigger 1442421: Swift detection of HMXB 1A 1118-61
  43. GRB 260117A: Swift-XRT afterglow detection
  44. GRB 260117A: ZTSh optical upper limit
  45. Swift GRB260118.48: Global MASTER-Net observations report
  46. GRB 260117A: SVOM/COLIBRÍ (FM-GFT) optical observations
  47. Swift trigger on the HMXB 1A 1118-61
  48. GRB 260117A: SVOM/VT optical candidate
  49. GRB 260117A: SVOM/C-GFT upper limit
  50. GRB 260117A: Swift-XRT observations
  51. GRB 260117A: Swift ToO observations
  52. Swift triggered on the HMXB 1A 1118-61
  53. GRB 260114A: VLT/MUSE spectroscopic observations
  54. GRB 260111A: COLIBRÍ fading of the optical counterpart candidate
  55. GRB 260114A: VLT/HAWK-I further near-infrared upper limits
  56. GRB260114A: STEP/T80S optical limits
  57. GRB 251222A: radio detection with the VLA
  58. GRB 260114A: VLT/HAWK-I near-infrared upper limits
  59. Konus-Wind detection of GRB 260114A
  60. GRB 260114A: Swift-XRT refined Analysis
  61. GRB 260114A: 6 GHz VLA observations
  62. GRB 260114A: VLT/X-shooter redshift of the putative host galaxy
  63. GRB 260114A : MITSuME Akeno optical upper limits
  64. GRB 260114A: COLIBRÍ optical upper limits
  65. GRB 260114A: TNG NIR upper limit
  66. GRB 260114A: NOT optical observations
  67. Konus-Wind detection of GRB 251230A / EP251230a
  68. GRB 260114A: SVOM/GRM observation of a short burst
  69. Swift GRB 260114A: Global MASTER-Net observations report
  70. GRB 260114A: GECAM-B observation of a short burst
  71. GRB 260114A: Mondy optical observations
  72. GRB 260114A: Fermi GBM observation
  73. GRB 260114A: GMG Optical Observation
  74. GRB 260114A: Swift detection of a short burst
  75. Swift GRB260113.43: Global MASTER-Net observations report
  76. Konus-Wind detection of GRB 260101A
  77. GRB 260111A: Swift-XRT observations
  78. Swift Trigger 1439093: is probably not GRB 260113A
  79. GRB 260111A: COLIBRÍ optical afterglow candidate
  80. GRB 260111A: Fermi GBM Observation
  81. Swift Trigger 1434591 is not a GRB
  82. GRB 260111A: Swift ToO observations
  83. GRB 260111A: Swift/BAT-GUANO arcminute localization of a burst
  84. Swift trigger 1436759 is not an astrophysical event
  85. GRB 260109C: LCO optical upper limits
  86. GRB 260109C: Kilonova-Catcher optical upper limit
  87. Swift Trigger 1434591: possible GRB 260109C
  88. GRB 260102A: Swift-XRT afterglow detection
  89. GRB 260104A: Swift-BAT refined analysis
  90. GRB 260101A: Swift-BAT refined analysis
  91. Swift GRB 251230A: Global MASTER-Net OT detection
  92. Swift GRB 260104A: Global MASTER-Net observations report
  93. GRB 260104A: Swift-XRT refined Analysis
  94. GRB 260104A: Enhanced Swift-XRT position
  95. GRB 260101A: Swift/UVOT Detection
  96. GRB 260104A: Swift detection of a burst
  97. GRB 260102A: LCO optical upper limits
  98. GRB 260102A: Swift-XRT observations
  99. GRB 251230A / EP251230a: GECAM-B detection
  100. GRB 260102A: SVOM/VT optical counterpart

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