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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"

3838 results found.

  1. Fermi trigger No 653151835: Global MASTER-Net observations report
  2. GRB 210912A: Mondy optical afterglow confirmation
  3. Swift GRB 210912A: Global MASTER-Net observations report
  4. GECAM observations of bursts from SGR J1935+2154 (2021-09-11T07 to 2021-09-12T08)
  5. Fermi trigger No 653084584: Global MASTER-Net observations report
  6. Fermi trigger No 653083551: Global MASTER-Net observations report
  7. Fermi trigger No 653066130: Global MASTER-Net observations report
  8. Fermi trigger No 653072474: Global MASTER-Net observations report
  9. Fermi trigger No 653054042: Global MASTER-Net observations report
  10. Fermi trigger No 653022153: Global MASTER-Net observations report
  11. Fermi GBM observation of a bright flare in the direction of SGR 1935+2154
  12. Konus-Wind detection of the second intermediate flare from SGR 1935+2154
  13. IPN triangulation of a bright burst from SGR 1935+2154
  14. GRB 210909B: GECAM detection
  15. GECAM observations of a series of bursts from SGR J1935+2154
  16. Swift detection of a burst from SGR Swift J1555.2-5402
  17. GECAM observation of a burst from SGR J1935+2154
  18. GECAM observation of a burst from SGR J1935+2154
  19. GRB 210619B: Maidanak and Assy optical observations, broken power law parametrization
  20. Fermi trigger No 652911693: Global MASTER-Net observations report
  21. Fermi trigger No 652906639: Global MASTER-Net observations report
  22. GECAM observation of a burst from SGR J1555.2-5402
  23. Fermi GBM trigger 652585475 / 210906073 is not a GRB
  24. Fermi trigger No 652585475: Global MASTER-Net observations report
  25. GRB 210827B: GECAM detection
  26. Fermi GBM observation of a burst from SGR J1555.2-5402
  27. Integral GRB210829.17: Global MASTER-Net observations report
  28. Integral GRB210829.14: Global MASTER-Net observations report
  29. Fermi GRB 210827A: Global MASTER-Net observations report
  30. POLAR detection of a SGR-like burst
  31. GRB 210824A: MITSuME Akeno optical upper limits
  32. Swift detection of an outburst from SGR Swift J1555.2-5402
  33. GRB 210822A: GECAM refined analysis
  34. Konus-Wind detection of GRB 210822A
  35. Fermi GRB 210822B: Global MASTER-Net observations report
  36. GRB 210822A: Nanshan/NEXT optical observations
  37. GRB 210822A: GECAM detection
  38. GRB 210820A: LT optical upper limit
  39. Fermi GRB 210813A: Global MASTER-Net observations report
  40. SGR 1935+2154: SPI INTEGRAL observations on 2021 August 5
  41. Fermi GRB 210807C: Global MASTER-Net observations report
  42. Fermi trigger No 650046564: Global MASTER-Net observations report
  43. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 August 5
  44. IPN Triangulation of a bright burst from SGR 1935+2154
  45. Fermi trigger No 649814537: Global MASTER-Net observations report
  46. Fermi trigger No 649684549: Global MASTER-Net observations report
  47. Swift GRB210731.62: Global MASTER-Net observations report
  48. GRB 210731A: MeerLICHT optical afterglow detection
  49. GRB 210730A: Campo Imperatore optical observations
  50. GRB 210726A: Chandra detection of the X-ray afterglow
  51. GRB 210730A: Swift detection of a burst near M82
  52. Fermi trigger No 648959581: Global MASTER-Net observations report
  53. Fermi trigger No 648868114: Global MASTER-Net observations report
  54. Fermi trigger No 648602917: Global MASTER-Net observations report
  55. GRB 210719A: GECAM detection
  56. IceCube-210717A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  57. GECAM detection of a short burst from SGR J1935+2154
  58. Recent activity of SGR 1935+2154 as observed by CGBM
  59. Fermi trigger No 647805873: Global MASTER-Net observations report
  60. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 10
  61. GECAM detection of a short burst from SGR J1935+2154
  62. Fermi trigger No 647641569: Global MASTER-Net observations report
  63. Fermi trigger No 647624281: Global MASTER-Net observations report
  64. GECAM detection of a short burst from SGR J1935+2154
  65. GECAM detection of a short burst from SGR 1935+2154
  66. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 7
  67. GECAM detection of a short burst from SGR 1935+2154
  68. Fermi trigger No 647365516: Global MASTER-Net observations report
  69. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 6
  70. Fermi GBM Observations of SGR J1935+2154
  71. Swift-BAT detection of a burst from SGR 1935+2154
  72. GECAM detection of a bright short burst from SGR 1935+2154
  73. Integral GRB210707.02: Global MASTER-Net observations report
  74. INTEGRAL detection of a burst from SGR 1935+2154
  75. IceCube-210629A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  76. Fermi-LAT Gamma-ray Observations of IceCube-210629A
  77. GRB 210627B: GECAM detection
  78. IceCube Alert 210629.76: Global MASTER-Net observations report
  79. IceCube-210629A - IceCube observation of a high-energy neutrino candidate track-like event
  80. Fermi trigger No 646443989: Global MASTER-Net observations report
  81. Fermi GRB 210627A: Global MASTER-Net observations report
  82. GRB 210627A: Fermi GBM Final Real-time Localization
  83. Fermi GRB 210626A: Global MASTER-Net observations report
  84. Fermi GRB 210625A: Global MASTER-Net observations report
  85. Fermi trigger No 646189108: Global MASTER-Net observations report
  86. Fermi GBM observation of a bright burst in the direction of SGR 1935+2154
  87. GRB 210619B: Abbey Ridge Observatory optical afterglow observation
  88. GECAM detection of GRB 210622B
  89. Swift Trigger 1057131: detection of a burst from SGR Swift J1555.2-5402
  90. GECAM detection of GRB 210619B
  91. Fermi GRB 210615A: Global MASTER-Net observations report
  92. Follow-up on HAWC Transient Monitoring Alert J0020+3108
  93. GRB 210610B: optical photometry of afterglow at INASAN/Simeiz
  94. GRB 210610A: CrAO/ZTSH optical observations
  95. GRB 210610B: Zwicky Transient Facility afterglow detection
  96. HAWC Transient Monitoring Alert: Significant Spot after 3 transits
  97. GRB210610B: MeerLICHT multi-colour photometry
  98. Fermi trigger No 645047470: Global MASTER-Net observations report
  99. Swift GRB 210610B: Global MASTER-Net observations report
  100. GRB 210610B: Swift detection of a burst with bright optical afterglow

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