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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"

788 results found.

  1. LIGO/Virgo S191129u: Coverage and upper limits from MAXI/GSC observations
  2. LIGO/Virgo S191110af: Coverage and upper limits from MAXI/GSC observations
  3. LIGO/Virgo S191109d: Coverage and upper limits from MAXI/GSC observations
  4. LIGO/Virgo S191105e: Coverage and upper limits from MAXI/GSC observations
  5. LIGO/Virgo S190930t: Coverage and upper limits from MAXI/GSC observations
  6. LIGO/Virgo S190930s: Coverage and upper limits from MAXI/GSC observations
  7. LIGO/Virgo S190924h: Coverage and upper limits from MAXI/GSC observations
  8. LIGO/Virgo S190923y: Coverage and upper limits from MAXI/GSC observations
  9. LIGO/Virgo S190915ak: Coverage and upper limits from MAXI/GSC observations
  10. LIGO/Virgo S190910h: Coverage and upper limits from MAXI/GSC observations
  11. Swift Trigger 924641 is an outburst from MAXI J1807+132
  12. LIGO/Virgo S190910d: Coverage and upper limits from MAXI/GSC observations
  13. GRB 190823A: Swift-XRT afterglow detection
  14. LIGO/Virgo S190901ap: Coverage and upper limits from MAXI/GSC observations
  15. GRB 190828A: Swift-XRT observations
  16. GRB 190828A: Tiled Swift observations
  17. LIGO/Virgo S190828l: Coverage and upper limits from MAXI/GSC observations
  18. LIGO/Virgo S190828j: Coverage and upper limits from MAXI/GSC observations
  19. GRB 190828A: MAXI/GSC detection
  20. GRB 190823A: Swift-XRT observations
  21. GRB 190823A: Tiled Swift observations
  22. GRB 190823A: MAXI/GSC detection
  23. Fermi GBM-190816: Coverage and upper limits from MAXI/GSC observations
  24. LIGO/Virgo S190814bv: Coverage and upper limits from MAXI/GSC observations
  25. IPN triangulation of GRB 190805B
  26. LIGO/Virgo S190808ae: Coverage and upper limits from MAXI/GSC observations
  27. GRB 190805B: AstroSat CZTI detection
  28. GRB 190804B: Swift-XRT afterglow detection
  29. Konus-Wind observation of GRB 190805B
  30. GRB 190805B: Swift-XRT observations
  31. GRB 190805B: Fermi GBM detection
  32. GRB 190805B: Tiled Swift observations
  33. GRB 190804B: Swift-XRT observations
  34. GRB 190805B: MAXI/GSC detection
  35. MAXI GRB190804.33 Global MASTER-Net observations report
  36. GRB 190804B: Tiled Swift observations
  37. GRB 190804B: MAXI/GSC detection
  38. LIGO/Virgo S190728q: Coverage and upper limits from MAXI/GSC observations
  39. LIGO/Virgo S190727h: Coverage and upper limits from MAXI/GSC observations
  40. LIGO/Virgo S190720a: Coverage and upper limits from MAXI/GSC observations
  41. LIGO/Virgo S190718y: Coverage and upper limits from MAXI/GSC observations
  42. GRB 190714A: an X-ray flare from 2E 1624.6+1504/UCAC4 525-061488
  43. GRB 190708B: confirmation of the X-ray afterglow
  44. GRB 190714A: Tiled Swift observations
  45. GRB 190714A: MAXI/GSC detection
  46. GRB 190708B: Swift-XRT observations
  47. Konus-Wind observation of GRB 190708B
  48. GRB 190708B: Tiled Swift observations
  49. MAXI GRB190708.83 Global MASTER-Net observations report
  50. GRB 190708B: MAXI/GSC detection
  51. LIGO/Virgo S190707q: Coverage and upper limits from MAXI/GSC observations
  52. LIGO/Virgo S190706ai: Coverage and upper limits from MAXI/GSC observations
  53. GRB 190706A: MAXI/GSC detection
  54. LIGO/Virgo S190701ah: Coverage and upper limits from MAXI/GSC observations
  55. GRB 190701A: MAXI/GSC detection
  56. LIGO/Virgo S190630ag: Coverage and upper limits from MAXI/GSC observations
  57. LIGO/Virgo S190602aq: Coverage and upper limits from MAXI/GSC observations
  58. LIGO/Virgo S190521r: Coverage and upper limits from MAXI/GSC observations
  59. IGO/Virgo S190521g: Coverage and upper limits from MAXI/GSC observations
  60. LIGO/Virgo S190519bj: MAXI/GSC Observations
  61. LIGO/Virgo S190517h: MAXI/GSC Observations
  62. LIGO/Virgo S190513bm: MAXI/GSC Observations
  63. LIGO/Virgo S190512at: MAXI/GSC Observations
  64. LIGO/Virgo S190510g: CLU/NED Galaxies in the Localization Volume
  65. LIGO/Virgo S190510g: MAXI/GSC Observations
  66. LIGO/Virgo S190503bf: MAXI/GSC Observations
  67. LIGO/Virgo S190426c: MAXI/GSC Observations
  68. LIGO/Virgo S190425z: MAXI/GSC Observations
  69. LIGO/Virgo S190421ar: MAXI/GSC Observations
  70. Corrections: GRB 190404A (not 140404B ) and GRB 190404B (not 140404C)
  71. LIGO/Virgo S190412m: MAXI/GSC Observations
  72. LIGO/Virgo S190408an: MAXI/GSC Observations
  73. GRB 190404C: MITSuME Akeno and Okayama optical upper limits
  74. Konus-Wind observation of GRB 190404B
  75. CORRECTED TARGET NAME: GRB 190408A: MAXI/GSC detection
  76. GRB 140408A: MAXI/GSC detection
  77. GRB 190404C: Swift-XRT afterglow detection
  78. GRB 190404B: CALET Gamma-Ray Burst Monitor detection
  79. GRB 190404C: Swift-XRT observations
  80. GRB190404C: GROWTH-India discovery of optical counterpart
  81. GRB 190404B: Tiled Swift observations
  82. GRB 140404C: MAXI/GSC detection
  83. GRB 140404B: MAXI/GSC detection
  84. GRB190305A: MASTER Global Robotic Net optical observation
  85. GRB 190305A: Swift-XRT afterglow detection
  86. GRB 190305A: CALET Gamma-Ray Burst Monitor detection
  87. GRB 190306A: Swift-XRT observations
  88. Konus-Wind observation of GRB 190305A
  89. GRB 190306A: Tiled Swift observations
  90. GRB 190306A: MAXI/GSC detection
  91. IPN Triangulation of GRB 190305A
  92. GRB 190305A: Swift-XRT observations
  93. GRB 190305A: Insight-HXMT/HE detection
  94. GRB 190305A: MAXI/GSC detection
  95. Trigger 890732: Swift detection of MAXI J1631-479
  96. Trigger 888312: Swift detection of 4U 1901+03
  97. GRB 190204A: CALET Gamma-Ray Burst Monitor detection
  98. Konus-Wind observation of GRB 190204A
  99. GRB 190204A: AstroSat CZTI detection
  100. GRB 190204A: MAXI/GSC detection

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