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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"

820 results found.

  1. LIGO/Virgo S200112r: Coverage and upper limits from MAXI/GSC observations
  2. LIGO/Virgo S200105ae: Coverage and upper limits from MAXI/GSC observations
  3. GRB 200105A: MAXI/GSC detection
  4. Fermi trigger No 598988276: Global MASTER-Net observations report
  5. LIGO/Virgo S191222n: Coverage and upper limits from MAXI/GSC observations
  6. LIGO/Virgo S191216ap: Coverage and upper limits from MAXI/GSC observations
  7. LIGO/Virgo S191215w: Coverage and upper limits from MAXI/GSC observations
  8. LIGO/Virgo S191213g: Coverage and upper limits from MAXI/GSC observations
  9. LIGO/Virgo S191205ah: Coverage and upper limits from MAXI/GSC observations
  10. LIGO/Virgo S191204r: Coverage and upper limits from MAXI/GSC observations
  11. LIGO/Virgo S191129u: Coverage and upper limits from MAXI/GSC observations
  12. LIGO/Virgo S191110af: Coverage and upper limits from MAXI/GSC observations
  13. LIGO/Virgo S191109d: Coverage and upper limits from MAXI/GSC observations
  14. LIGO/Virgo S191105e: Coverage and upper limits from MAXI/GSC observations
  15. LIGO/Virgo S190930t: Coverage and upper limits from MAXI/GSC observations
  16. LIGO/Virgo S190930s: Coverage and upper limits from MAXI/GSC observations
  17. LIGO/Virgo S190924h: Coverage and upper limits from MAXI/GSC observations
  18. LIGO/Virgo S190923y: Coverage and upper limits from MAXI/GSC observations
  19. LIGO/Virgo S190915ak: Coverage and upper limits from MAXI/GSC observations
  20. LIGO/Virgo S190910h: Coverage and upper limits from MAXI/GSC observations
  21. Swift Trigger 924641 is an outburst from MAXI J1807+132
  22. LIGO/Virgo S190910d: Coverage and upper limits from MAXI/GSC observations
  23. GRB 190823A: Swift-XRT afterglow detection
  24. LIGO/Virgo S190901ap: Coverage and upper limits from MAXI/GSC observations
  25. GRB 190828A: Swift-XRT observations
  26. GRB 190828A: Tiled Swift observations
  27. LIGO/Virgo S190828l: Coverage and upper limits from MAXI/GSC observations
  28. LIGO/Virgo S190828j: Coverage and upper limits from MAXI/GSC observations
  29. GRB 190828A: MAXI/GSC detection
  30. GRB 190823A: Swift-XRT observations
  31. GRB 190823A: Tiled Swift observations
  32. GRB 190823A: MAXI/GSC detection
  33. Fermi GBM-190816: Coverage and upper limits from MAXI/GSC observations
  34. LIGO/Virgo S190814bv: Coverage and upper limits from MAXI/GSC observations
  35. IPN triangulation of GRB 190805B
  36. LIGO/Virgo S190808ae: Coverage and upper limits from MAXI/GSC observations
  37. GRB 190805B: AstroSat CZTI detection
  38. GRB 190804B: Swift-XRT afterglow detection
  39. Konus-Wind observation of GRB 190805B
  40. GRB 190805B: Swift-XRT observations
  41. GRB 190805B: Fermi GBM detection
  42. GRB 190805B: Tiled Swift observations
  43. GRB 190804B: Swift-XRT observations
  44. GRB 190805B: MAXI/GSC detection
  45. MAXI GRB190804.33 Global MASTER-Net observations report
  46. GRB 190804B: Tiled Swift observations
  47. GRB 190804B: MAXI/GSC detection
  48. LIGO/Virgo S190728q: Coverage and upper limits from MAXI/GSC observations
  49. LIGO/Virgo S190727h: Coverage and upper limits from MAXI/GSC observations
  50. LIGO/Virgo S190720a: Coverage and upper limits from MAXI/GSC observations
  51. LIGO/Virgo S190718y: Coverage and upper limits from MAXI/GSC observations
  52. GRB 190714A: an X-ray flare from 2E 1624.6+1504/UCAC4 525-061488
  53. GRB 190708B: confirmation of the X-ray afterglow
  54. GRB 190714A: Tiled Swift observations
  55. GRB 190714A: MAXI/GSC detection
  56. GRB 190708B: Swift-XRT observations
  57. Konus-Wind observation of GRB 190708B
  58. GRB 190708B: Tiled Swift observations
  59. MAXI GRB190708.83 Global MASTER-Net observations report
  60. GRB 190708B: MAXI/GSC detection
  61. LIGO/Virgo S190707q: Coverage and upper limits from MAXI/GSC observations
  62. LIGO/Virgo S190706ai: Coverage and upper limits from MAXI/GSC observations
  63. GRB 190706A: MAXI/GSC detection
  64. LIGO/Virgo S190701ah: Coverage and upper limits from MAXI/GSC observations
  65. GRB 190630C: AstroSat CZTI detection
  66. GRB 190701A: MAXI/GSC detection
  67. LIGO/Virgo S190630ag: Coverage and upper limits from MAXI/GSC observations
  68. LIGO/Virgo S190602aq: Coverage and upper limits from MAXI/GSC observations
  69. LIGO/Virgo S190521r: Coverage and upper limits from MAXI/GSC observations
  70. IGO/Virgo S190521g: Coverage and upper limits from MAXI/GSC observations
  71. LIGO/Virgo S190519bj: MAXI/GSC Observations
  72. LIGO/Virgo S190517h: MAXI/GSC Observations
  73. LIGO/Virgo S190513bm: MAXI/GSC Observations
  74. LIGO/Virgo S190512at: MAXI/GSC Observations
  75. LIGO/Virgo S190510g: MAXI/GSC Observations
  76. LIGO/Virgo S190503bf: MAXI/GSC Observations
  77. LIGO/Virgo S190426c: MAXI/GSC Observations
  78. LIGO/Virgo S190425z: MAXI/GSC Observations
  79. LIGO/Virgo S190421ar: MAXI/GSC Observations
  80. Corrections: GRB 190404A (not 140404B ) and GRB 190404B (not 140404C)
  81. LIGO/Virgo S190412m: MAXI/GSC Observations
  82. LIGO/Virgo S190408an: MAXI/GSC Observations
  83. GRB 190404C: MITSuME Akeno and Okayama optical upper limits
  84. Konus-Wind observation of GRB 190404B
  85. CORRECTED TARGET NAME: GRB 190408A: MAXI/GSC detection
  86. GRB 140408A: MAXI/GSC detection
  87. GRB 190404C: Swift-XRT afterglow detection
  88. GRB 190404B: CALET Gamma-Ray Burst Monitor detection
  89. GRB 190404C: Swift-XRT observations
  90. GRB190404C: GROWTH-India discovery of optical counterpart
  91. GRB 190404B: Tiled Swift observations
  92. GRB 140404C: MAXI/GSC detection
  93. GRB 140404B: MAXI/GSC detection
  94. GRB190305A: MASTER Global Robotic Net optical observation
  95. GRB 190305A: Swift-XRT afterglow detection
  96. GRB 190305A: CALET Gamma-Ray Burst Monitor detection
  97. GRB 190306A: Swift-XRT observations
  98. Konus-Wind observation of GRB 190305A
  99. GRB 190306A: Tiled Swift observations
  100. GRB 190306A: MAXI/GSC detection

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