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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').
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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"

11546 results found.

  1. IceCube-200421A: not observable by Fermi-GBM
  2. IceCube-200421A - IceCube observation of a high-energy neutrino candidate event
  3. GRB 200412B: continued Mondy and Terskol optical observations
  4. GRB 200420: Fermi GBM Final Localization Correction
  5. Fermi GRB 200420A: Global MASTER-Net observations report
  6. GRB 200420A: Fermi GBM Final Real-time Localization
  7. Fermi trigger No 608935505: Global MASTER-Net observations report
  8. GRB 200412B: continued Terskol optical observations
  9. GRB 200412B: continued AbAO, Mondy, TSHAO, Terskol optical observations
  10. GRB200412B: GROWTH India detection of afterglow
  11. GRB 200415A: Fermi-LAT localization update
  12. Konus-Wind observation of GRB 200415A (a magnetar Giant Flare in Sculptor Galaxy?)
  13. Improved IPN error box for GRB 200415A (consistent with the Sculptor Galaxy)
  14. GRB 200412B: continued Tautenburg observations
  15. GRB 200416A: Fermi GBM observation
  16. Fermi GRB 200415A: Global MASTER-Net observations report
  17. GRB 200411A: Chandra observations indicative of temporal steepening
  18. GRB 200412A : AstroSat CZTI detection
  19. GRB 200415A: Fermi GBM observation
  20. GRB 200415A: Fermi-LAT detection
  21. IPN triangulation of GRB 200415A (possible Magnetar Giant Flare in Sculptor Galaxy?)
  22. GRB 200412B: Mondy optical observations
  23. GRB 200412B: continued Tautenburg observations
  24. Konus-Wind observation of GRB 200412B
  25. GRB 200415A: BALROG localization (Fermi Trigger 608633290 / GRB 200415367)
  26. GRB 200415A: Fermi GBM Final Real-time Localization
  27. Konus-Wind observation of GRB 200412A
  28. GRB 200412B: MITSuME Akeno optical observation
  29. GRB 200412B: Tautenburg observations
  30. GRB 200412B: contunued AbAO optical observations
  31. GRB 200411A: ATCA 5/9 GHz radio observations
  32. GRB 200412B: CALET Gamma-Ray Burst Monitor detection
  33. GRB 200412B: Xinglong TNT optical observations
  34. GRB 200412B: SAO RAS observations of OT
  35. GRB 200412B: Tautenburg observations
  36. GRB 200412B: AbAO optical observations
  37. GRB 200412B: Insight-HXMT/HE detection
  38. GRB 200412B: Optical afterglow detection with 1.3m DFOT
  39. GRB 200412B : AstroSat CZTI detection
  40. GRB 200412B: Swift-XRT afterglow detection
  41. IPN triangulation of GRB 200412A
  42. Fermi GRB 200412A: Global MASTER-Net observations report
  43. GRB 200412B: Fermi GBM detection
  44. GRB 200412B: Fermi-LAT detection
  45. GRB 200412B: MASTER Optical Couterpart in Gagarin day!
  46. Konus-Wind observation of a bright burst from SGR 1935+2154
  47. GRB 200412B: Tiled Swift observations
  48. GRB 200412A: Fermi GBM detection
  49. Fermi GRB 200412B: Global MASTER-Net observations report
  50. GRB 200412B: BALROG localization (Fermi Trigger 608375325 / GRB 200412381)
  51. GRB 200412B: Fermi GBM Final Real-time Localization
  52. GRB 200412A: BALROG localization (Fermi Trigger 608367436 / GRB 200412290)
  53. Fermi-LAT Gamma-ray Observations of IceCube-200410A
  54. GRB 200411A: Fermi GBM observation
  55. IceCube-200410A: Upper limits from Fermi-GBM Observations
  56. GRB 200411A: Fermi GBM Final Real-time Localization
  57. IceCube-200410A - IceCube observation of a high-energy neutrino candidate event
  58. SGR 1935+2154: Fermi GBM observation
  59. Fermi trigger No 608204639: Global MASTER-Net observations report
  60. IPN Triangulation of a bright burst from SGR 1935+2154
  61. Konus-Wind observation of GRB 200327A
  62. Fermi GBM Sub-Threshold Detection of GRB 200409A
  63. Fermi GRB 200407A: Global MASTER-Net observations report
  64. Fermi GRB 200407B: Global MASTER-Net observations report
  65. IPN triangulation of GRB 200407A (short)
  66. GRB 200407B: Fermi GBM Final Real-time Localization
  67. GRB 200407A: Fermi GBM Final Real-time Localization
  68. Fermi GRB 200405A: Global MASTER-Net observations report
  69. GRB 200405A: Fermi GBM Final Real-time Localization
  70. GRB 200404A: Fermi GBM Final Localization
  71. Fermi GRB 200403C: Global MASTER-Net observations report
  72. GRB 200404A: BALROG localization (Fermi Trigger 607712227 / GRB 200404706)
  73. GRB 200403A: AstroSat CZTI detection
  74. Fermi GRB 200403B: Global MASTER-Net observations report
  75. Fermi GRB 200403A: Global MASTER-Net observations report
  76. GRB 200403C: Fermi GBM Final Real-time Localization
  77. GRB 200403B: Fermi GBM Final Real-time Localization
  78. GRB 200403A: Fermi GBM Final Real-time Localization
  79. GRB 200325B: Mondy continued observations
  80. Fermi GRB 200402C: Global MASTER-Net observations report
  81. GRB 200402C: Fermi GBM Final Localization
  82. GRB 200402B: Fermi GBM Final Localization
  83. Fermi trigger No 607537834: Global MASTER-Net observations report
  84. GRB 200402B: BALROG localization (Fermi Trigger 607537834 / GRB 200402688)
  85. Fermi GRB 200402A: Global MASTER-Net observations report
  86. GRB 200402A: BALROG localization (Fermi Trigger 607513182 / GRB 200402403)
  87. GRB 200325B: Optical upper limit
  88. GRB 200402A: Fermi GBM Final Real-time Localization
  89. GRB 200325B: further Swift-XRT observations
  90. Fermi GRB 200401A: Global MASTER-Net observations report
  91. GRB 200401A: Fermi GBM Final Real-time Localization
  92. GRB 200325B: Mondy continued observations
  93. GRB 200325B: Mondy continued observations
  94. GRB 200327A: Fermi GBM detection
  95. GRB 200325B: Mondy continued observations
  96. GRB 200325B: Tautenburg observations
  97. IPN triangulation of GRB 200327A (short)
  98. GRB 200327A: AGILE/MCAL observations
  99. GRB 200325B: Fermi GBM observation
  100. Fermi trigger No 607035413: Global MASTER-Net observations report

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