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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"

850 results found.

  1. LIGO/Virgo S200302c: Coverage and upper limits from MAXI/GSC observations
  2. LIGO/Virgo S200225q: Coverage and upper limits from MAXI/GSC observations
  3. LIGO/Virgo S200224ca: Coverage and upper limits from MAXI/GSC observations
  4. LIGO/Virgo S200219ac: Coverage and upper limits from MAXI/GSC observations
  5. LIGO/Virgo S200213t: Coverage and upper limits from MAXI/GSC observations
  6. LIGO/Virgo S200208q: Coverage and upper limits from MAXI/GSC observations
  7. GRB 200205A = Swift J0840.7-3516, A newly discovered transient X-ray Pulsar
  8. GRB 200205A / Swift trigger 954304: VLT optical observations
  9. GRB 200205A: MAXI/GSC detection
  10. MAXI GRB200205.29: Global MASTER-Net observations report
  11. LIGO/Virgo S200129m: Coverage and upper limits from MAXI/GSC observations
  12. LIGO/Virgo S200128d: Coverage and upper limits from MAXI/GSC observations
  13. LIGO/Virgo S200115j: Coverage and upper limits from MAXI/GSC observations
  14. LIGO/Virgo S200114f: Coverage and upper limits from MAXI/GSC observations
  15. LIGO/Virgo S200112r: Coverage and upper limits from MAXI/GSC observations
  16. LIGO/Virgo S200105ae: Coverage and upper limits from MAXI/GSC observations
  17. GRB 200105A: MAXI/GSC detection
  18. Swift GRB191226.02: Global MASTER-Net observations report
  19. LIGO/Virgo S191222n: Coverage and upper limits from MAXI/GSC observations
  20. LIGO/Virgo S191216ap: Coverage and upper limits from MAXI/GSC observations
  21. LIGO/Virgo S191215w: Coverage and upper limits from MAXI/GSC observations
  22. LIGO/Virgo S191213g: Coverage and upper limits from MAXI/GSC observations
  23. LIGO/Virgo S191205ah: Coverage and upper limits from MAXI/GSC observations
  24. LIGO/Virgo S191204r: Coverage and upper limits from MAXI/GSC observations
  25. LIGO/Virgo S191129u: Coverage and upper limits from MAXI/GSC observations
  26. LIGO/Virgo S191110af: Coverage and upper limits from MAXI/GSC observations
  27. LIGO/Virgo S191109d: Coverage and upper limits from MAXI/GSC observations
  28. LIGO/Virgo S191105e: Coverage and upper limits from MAXI/GSC observations
  29. LIGO/Virgo S190930t: Coverage and upper limits from MAXI/GSC observations
  30. LIGO/Virgo S190930s: Coverage and upper limits from MAXI/GSC observations
  31. LIGO/Virgo S190924h: Coverage and upper limits from MAXI/GSC observations
  32. LIGO/Virgo S190923y: Coverage and upper limits from MAXI/GSC observations
  33. LIGO/Virgo S190915ak: Coverage and upper limits from MAXI/GSC observations
  34. LIGO/Virgo S190910h: Coverage and upper limits from MAXI/GSC observations
  35. Swift Trigger 924641 is an outburst from MAXI J1807+132
  36. LIGO/Virgo S190910d: Coverage and upper limits from MAXI/GSC observations
  37. GRB 190823A: Swift-XRT afterglow detection
  38. LIGO/Virgo S190901ap: Coverage and upper limits from MAXI/GSC observations
  39. GRB 190828A: Swift-XRT observations
  40. GRB 190828A: Tiled Swift observations
  41. LIGO/Virgo S190828l: Coverage and upper limits from MAXI/GSC observations
  42. LIGO/Virgo S190828j: Coverage and upper limits from MAXI/GSC observations
  43. GRB 190828A: MAXI/GSC detection
  44. GRB 190823A: Swift-XRT observations
  45. GRB 190823A: Tiled Swift observations
  46. GRB 190823A: MAXI/GSC detection
  47. Fermi GBM-190816: Coverage and upper limits from MAXI/GSC observations
  48. LIGO/Virgo S190814bv: Coverage and upper limits from MAXI/GSC observations
  49. IPN triangulation of GRB 190805B
  50. LIGO/Virgo S190808ae: Coverage and upper limits from MAXI/GSC observations
  51. GRB 190804A: AstroSat CZTI detection
  52. GRB 190805B: AstroSat CZTI detection
  53. GRB 190804B: Swift-XRT afterglow detection
  54. Konus-Wind observation of GRB 190805B
  55. GRB 190805B: Swift-XRT observations
  56. GRB 190805B: Fermi GBM detection
  57. GRB 190805B: Tiled Swift observations
  58. GRB 190804B: Swift-XRT observations
  59. GRB 190805B: MAXI/GSC detection
  60. MAXI GRB190804.33 Global MASTER-Net observations report
  61. GRB 190804B: Tiled Swift observations
  62. GRB 190804B: MAXI/GSC detection
  63. LIGO/Virgo S190728q: Coverage and upper limits from MAXI/GSC observations
  64. LIGO/Virgo S190727h: No counterpart candidates in HAWC observations
  65. LIGO/Virgo S190727h: Coverage and upper limits from MAXI/GSC observations
  66. LIGO/Virgo S190720a: Coverage and upper limits from MAXI/GSC observations
  67. LIGO/Virgo S190718y: Coverage and upper limits from MAXI/GSC observations
  68. GRB 190714A: an X-ray flare from 2E 1624.6+1504/UCAC4 525-061488
  69. GRB 190708B: confirmation of the X-ray afterglow
  70. GRB 190714A: Tiled Swift observations
  71. GRB 190714A: MAXI/GSC detection
  72. GRB 190708B: Swift-XRT observations
  73. Konus-Wind observation of GRB 190708B
  74. GRB 190708B: Tiled Swift observations
  75. MAXI GRB190708.83 Global MASTER-Net observations report
  76. GRB 190708B: MAXI/GSC detection
  77. LIGO/Virgo S190707q: Coverage and upper limits from MAXI/GSC observations
  78. LIGO/Virgo S190706ai: Coverage and upper limits from MAXI/GSC observations
  79. GRB 190706A: MAXI/GSC detection
  80. LIGO/Virgo S190701ah: Coverage and upper limits from MAXI/GSC observations
  81. GRB 190701A: MAXI/GSC detection
  82. LIGO/Virgo S190630ag: Coverage and upper limits from MAXI/GSC observations
  83. Fermi trigger No 581478912 Global MASTER-Net observations report
  84. LIGO/Virgo S190602aq: Coverage and upper limits from MAXI/GSC observations
  85. LIGO/Virgo S190521r: Coverage and upper limits from MAXI/GSC observations
  86. IGO/Virgo S190521g: Coverage and upper limits from MAXI/GSC observations
  87. LIGO/Virgo S190519bj: MAXI/GSC Observations
  88. LIGO/Virgo S190517h: MAXI/GSC Observations
  89. LIGO/Virgo S190513bm: MAXI/GSC Observations
  90. LIGO/Virgo S190512at: MAXI/GSC Observations
  91. LIGO/Virgo S190510g: CLU/NED Galaxies in the Localization Volume
  92. LIGO/Virgo S190510g: MAXI/GSC Observations
  93. LIGO/Virgo S190503bf: MAXI/GSC Observations
  94. LIGO/Virgo S190426c: MAXI/GSC Observations
  95. LIGO/Virgo S190425z: MAXI/GSC Observations
  96. LIGO/Virgo S190421ar: MAXI/GSC Observations
  97. Corrections: GRB 190404A (not 140404B ) and GRB 190404B (not 140404C)
  98. LIGO/Virgo S190412m: MAXI/GSC Observations
  99. LIGO/Virgo S190408an: MAXI/GSC Observations
  100. GRB 190404C: MITSuME Akeno and Okayama optical upper limits

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