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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"

4180 results found.

  1. Fermi trigger No 647805873: Global MASTER-Net observations report
  2. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 10
  3. GECAM detection of a short burst from SGR J1935+2154
  4. Fermi trigger No 647641569: Global MASTER-Net observations report
  5. Fermi trigger No 647624281: Global MASTER-Net observations report
  6. GECAM detection of a short burst from SGR J1935+2154
  7. GECAM detection of a short burst from SGR 1935+2154
  8. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 7
  9. GECAM detection of a short burst from SGR 1935+2154
  10. Fermi trigger No 647365516: Global MASTER-Net observations report
  11. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 6
  12. Fermi GBM Observations of SGR J1935+2154
  13. Swift-BAT detection of a burst from SGR 1935+2154
  14. GECAM detection of a bright short burst from SGR 1935+2154
  15. Integral GRB210707.02: Global MASTER-Net observations report
  16. INTEGRAL detection of a burst from SGR 1935+2154
  17. IceCube-210629A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  18. Fermi-LAT Gamma-ray Observations of IceCube-210629A
  19. GRB 210627B: GECAM detection
  20. IceCube Alert 210629.76: Global MASTER-Net observations report
  21. IceCube-210629A - IceCube observation of a high-energy neutrino candidate track-like event
  22. Fermi trigger No 646443989: Global MASTER-Net observations report
  23. Fermi GRB 210627A: Global MASTER-Net observations report
  24. GRB 210627A: Fermi GBM Final Real-time Localization
  25. Fermi GRB 210626A: Global MASTER-Net observations report
  26. Fermi GRB 210625A: Global MASTER-Net observations report
  27. Fermi trigger No 646189108: Global MASTER-Net observations report
  28. Fermi GBM observation of a bright burst in the direction of SGR 1935+2154
  29. GRB 210619B: Abbey Ridge Observatory optical afterglow observation
  30. GECAM detection of GRB 210622B
  31. Swift Trigger 1057131: detection of a burst from SGR Swift J1555.2-5402
  32. GECAM detection of GRB 210619B
  33. Fermi GRB 210615A: Global MASTER-Net observations report
  34. Follow-up on HAWC Transient Monitoring Alert J0020+3108
  35. GRB 210610B: optical photometry of afterglow at INASAN/Simeiz
  36. GRB 210610A: CrAO/ZTSH optical observations
  37. GRB 210610B: Zwicky Transient Facility afterglow detection
  38. HAWC Transient Monitoring Alert: Significant Spot after 3 transits
  39. GRB210610B: MeerLICHT multi-colour photometry
  40. Fermi trigger No 645047470: Global MASTER-Net observations report
  41. Swift GRB 210610B: Global MASTER-Net observations report
  42. GRB 210610B: Swift detection of a burst with bright optical afterglow
  43. GRB 210610A: MITSuME Akeno optical observation
  44. GECAM Sub-Threshold Detection of new magnetar Swift SGR J1555.2-5402
  45. GRB 210606B: GECAM detection
  46. Fermi GBM Sub-Threshold Detection of new Swift SGR J1555.2-5402
  47. SGR J1555.2-5402: Swift-BAT refined analysis
  48. Fermi trigger No 644449593: Global MASTER-Net observations report
  49. Swift J1555.2-5402: Swift XRT refined analysis of the new SGR
  50. NICER discovery of 3.86 s pulsations from a new magnetar: SGR J1555.2-5402
  51. Swift Detection of probable new Swift SGR J1555.2-5402
  52. GRB 210602B: GECAM detection
  53. GRB 210529A: GECAM detection
  54. Fermi trigger No 644359567: Global MASTER-Net observations report
  55. Fermi GRB 210529A: Global MASTER-Net observations report
  56. Fermi GRB 210529B: Global MASTER-Net observations report
  57. GRB 210529B: Fermi GBM Final Real-time Localization
  58. GRB 210529A: Fermi GBM Final Real-time Localization
  59. GRB 210528B: DDOTI Upper Limits on the Afterglow
  60. GRB 210528B: MITSuME Akeno optical upper limits
  61. MAXI GRB210528.95: Global MASTER-Net observations report
  62. GRB 210528B: MAXI/GSC detection
  63. Fermi trigger No 643548039: Global MASTER-Net observations report
  64. GRB 210522A: GECAM detection
  65. GRB 210521A: MAXI/GSC detection
  66. GRB 210520A: GECAM detection
  67. Fermi GRB 210520A: Global MASTER-Net observations report
  68. Fermi GBM observation of a bright burst from magneta
  69. IPN triangulation of GRB 210518A
  70. Fermi trigger No 643065622: Global MASTER-Net observations report
  71. Fermi trigger No 642991619: Global MASTER-Net observations report
  72. GRB 210517A: Swift detection of a burst
  73. Fermi GRB 210515B: Global MASTER-Net observations report
  74. Fermi GRB 210515A: Global MASTER-Net observations report
  75. Fermi GRB 210511A: Global MASTER-Net observations report
  76. GRB 210511B: GECAM detection
  77. IceCube Alert 210510.20: Global MASTER-Net observations report
  78. Fermi GRB 210507A: Global MASTER-Net observations report
  79. ZTF21aayokph (AT2021lfa): MASTER OT detection 3h befor ZTF
  80. ZTF and LT observations of ZTF21aayokph (AT2021lfa), a fast-fading red transient
  81. Swift Detection of MAXI J1803-298 including an optical counterpart
  82. MAXI GRB210501.83: Global MASTER-Net observations report
  83. Fermi GRB 210501A: Global MASTER-Net observations report
  84. GRB 210424B: MITSuME Akeno optical upper limits
  85. Swift GRB210430.45: Global MASTER-Net observations report
  86. Swift Trigger 1045571 is not a GRB
  87. GRB 210427A: GECAM detection
  88. GRB 210425A: GECAM detection
  89. GRB 210420B: follow-up photometry of optical afterglow at INASAN/Simeiz
  90. GRB 210421A: GECAM detection
  91. Fermi GRB 210421C: Global MASTER-Net observations report
  92. GRB 210420B: Montarrenti Observatory follow-up observations
  93. GRB 210420B: Montarrenti Observatory optical afterglow detection
  94. GRB 210420A: Fermi GBM Final Real-time Localization
  95. GRB 210413A: GECAM detection
  96. Fermi GRB 210411B: Global MASTER-Net observations report
  97. Fermi GRB 210411A: Global MASTER-Net observations report
  98. GRB 210409A: GECAM detection
  99. Fermi GRB 210410A: Global MASTER-Net observations report
  100. GRB 210401A: GECAM detection

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