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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. GRB 210328A: GECAM detection
  2. GRB 210330A: GECAM detection
  3. Fermi trigger No 638414549: Global MASTER-Net observations report
  4. Fermi GRB 210324B: Global MASTER-Net observations report
  5. Fermi trigger No 637729731: Global MASTER-Net observations report
  6. GRB 210317A: GECAM detection
  7. GRB 210317A: Fermi GBM Final Real-time Localization
  8. Fermi trigger No 637521056: Global MASTER-Net observations report
  9. Fermi GRB 210312A: Global MASTER-Net observations report
  10. Fermi trigger No 637027080: Global MASTER-Net observations report
  11. GRB 210308A: Nanshan/NEXT optical upper limits
  12. GRB 210307B: GECAM detection
  13. GRB 210306A: Tautenburg observations
  14. GRB 210228A: GECAM detection
  15. GRB 210226A: Fermi GBM detection
  16. GRB 210222A: MAXI/GSC detection
  17. GRB 210205A: observations with the 3.6m DOT, a potential dark burst?
  18. Fermi/GBM observation of a burst from SGR 1830-0645
  19. GRB 210212A: Mondy optical observations
  20. GRB 210210A: Konus-Wind detection and joint Konus-Wind + Swift-BAT spectral analysis
  21. Swift Trigger 1033144: Detection of SGR 1830-0645
  22. Swift Trigger 1032350: Detection of SGR 1830-0645
  23. GRB 210204A: observations with the 3.6m Devasthal Optical Telescope and possible jet break
  24. GRB 210207B: GECAM detection
  25. GRB 210211A: Fermi GBM observation
  26. Swift-XRT observations of IceCube-210210A
  27. Fermi trigger No 634659312: Global MASTER-Net observations report
  28. SGR 1935+2154: MAXI/GSC detection
  29. GRB 210207B: optical detection with 3.6m Devasthal Optical Telescope
  30. Fermi GRB 210207A: Global MASTER-Net observations report
  31. GRB 210204A: Optical Observations from HCT
  32. IPN triangulation of GRB 210204A
  33. GRB 210205A: MITSuME Ishigaki optical observation
  34. GRB 210204: Fermi GBM observation
  35. GRB 210204A: GECAM detection
  36. GRB 210204A: BALROG localization (Fermi Trigger 634112970 / GRB 210204270)
  37. GRB 210204A: Fermi GBM Final Real-time Localization
  38. Fermi GBM Observations of a bright burst from SGR J1935+2154
  39. Recent activity of SGR 1935+2154 as observed by CGBM
  40. INTEGRAL detection of a short burst from SGR 1935+2154
  41. GRB 210131A: GECAM detection
  42. Fermi trigger No 633879387: Global MASTER-Net observations report
  43. GECAM observations of SGR 1935+2154
  44. Fermi GBM Observations of SGR J1935+2154
  45. Konus-Wind detection of two bright bursts from SGR 1935+2154
  46. IPN triangulation of a bright burst from SGR 1935+2154
  47. GECAM detection of a short burst probably from SGR 1935+2154
  48. GRB 210120A: Fermi GBM detection
  49. GRB 210126A: GECAM detection
  50. IPN triangulation of GRB 210124B (short)
  51. GECAM detection of a burst possibly from the X-ray burster 4U 0614+09 or GRB 210124A
  52. GRB 210121A: GECAM detection
  53. GECAM In-Flight Trigger of GRB 210120A
  54. Fermi GRB 210120A: Global MASTER-Net observations report
  55. GRB 210119A (Swift J1851.2-6148): Swift-BAT refined analysis
  56. GECAM detection of a short GRB 210119A or a new SGR candidate Swift J1851.2-6148
  57. GRB 210119A: Fermi GBM observation
  58. Short Fermi GRB 210119A or new SGR Swift J1851.2-6148: Possible MASTER Short OT detection
  59. Swift detection of a new SGR Swift J1851.2-6148 or a short GRB 210119A
  60. ZTF21aaeyldq: observations with the 3.6m Devasthal Optical Telescope
  61. GRB 210112A: OSN second epoch, decay
  62. GRB 210104A: AROMA-N Optical Afterglow Detection
  63. GRB 201227A: continued Chilescope confirmation of variability of possible optical counterpart, redshift estimating
  64. Fermi trigger No 631584650: Global MASTER-Net observations report
  65. GRB 210104A: MASTER OT rebrightening detection
  66. Fermi GRB 210104A: Global MASTER-Net observations report
  67. Fermi GRB 210102C: Global MASTER-Net observations report
  68. MAXI GRB210102.38: Global MASTER-Net observations report
  69. Fermi GRB 210101A: Global MASTER-Net observations report
  70. Fermi trigger No 631119348: Global MASTER-Net observations report
  71. Fermi trigger No 631118376: Global MASTER-Net observations report
  72. Fermi trigger No 631104264: Global MASTER-Net observations report
  73. GRB 201227A: Chilescope optical observations, possible optical counterpart
  74. GRB 201229A: AbAO optical afterglow detection, TSHAO optical upper limit
  75. GRB 201229A: Nanshan/NEXT optical upper limit
  76. GRB 201227A: Swift-XRT observations
  77. Fermi GRB 201229B: Global MASTER-Net observations report
  78. GRB 201229B: BALROG localization (Fermi Trigger 630948017 / GRB 201229639)
  79. GRB 201229B: Fermi GBM Final Real-time Localization
  80. ZTF20acozryr/AT2020yxz (GRB 201103B): Maidanak optical observations
  81. Fermi trigger No 630681391: Global MASTER-Net observations report
  82. GRB 201223A: Mondy and Kitab optical observations
  83. Konus-Wind detection of GRB 201216C
  84. GRB 201216C: AstroSat CZTI detection
  85. Fermi GRB 201216A: Global MASTER-Net observations report
  86. GRB 201015A: 5-GHz radio afterglow detection with the EVN
  87. Swift GRB201209.24: Global MASTER-Net observations report
  88. Swift GRB 201203A: Global MASTER-Net observations report
  89. IceCube-201130A: No significant detection in HAWC
  90. IceCube-201130A: Upper limits from a search for additional neutrino events in IceCube
  91. GRB 201121A: Insight-HXMT/HE detection
  92. INTEGRAL Weak #8831 and #8832: AROMA-N Optical Observation
  93. GRB 201121A: BALROG localization (Fermi Trigger 627614994 / GRB 201121062)
  94. GRB 201121A: Fermi GBM Final Real-time Localization
  95. IceCube-201120A: Upper limits from Fermi-GBM Observations
  96. Fermi-LAT Gamma-ray Observations of NuEm-201107A
  97. ZTF20acozryr/AT2020yxz (GRB 201103B): Mondy continued optical observations
  98. Fermi GRB 201111A: Global MASTER-Net observations report
  99. Swift Trigger 1005428: Detection of SGR 1830-0645
  100. GRB 201104B: MITSuME Akeno optical observation

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