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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

11612 results found.

  1. GRB 210202A: Fermi GBM detection
  2. GRB 210202A: Fermi-LAT detection
  3. Fermi GRB 210202A: Global MASTER-Net observations report
  4. Fermi trigger No 633963272: Global MASTER-Net observations report
  5. Recent activity of SGR 1935+2154 as observed by CGBM
  6. GRB 210202A: BALROG localization (Fermi Trigger / GRB 210202841)
  7. GRB 210202A: Fermi GBM Final Real-time Localization
  8. Fermi trigger No 633879387: Global MASTER-Net observations report
  9. Fermi GBM Observations of SGR J1935+2154
  10. GRB 140330A: Swift-XRT refined Analysis
  11. GRB 140402A: Swift-XRT refined Analysis
  12. GRB 140104B: Swift-XRT refined Analysis
  13. GRB 210126A: AstroSat CZTI detection
  14. GRB 210123A: AstroSat CZTI detection
  15. GRB 210127A: Fermi GBM Final Real-time Localization
  16. GRB 210120A: Fermi GBM detection
  17. Fermi trigger No 633348010: Global MASTER-Net observations report
  18. GRB 210126A: GECAM detection
  19. GRB 210126A: BALROG localization (Fermi Trigger / GRB 210126417)
  20. Fermi trigger No 633257525: Global MASTER-Net observations report
  21. GRB 210123A: Fermi GBM Final Localization
  22. GRB 210120A : 1.3m DFOT optical observations
  23. GRB 210120A(MASTER OT J105242.66+152355.0 / AT2021axc): Mondy optical observations
  24. GRB 210120A: MASTER OT (possibly) discovery
  25. GECAM In-Flight Trigger of GRB 210120A
  26. Fermi GRB 210120A: Global MASTER-Net observations report
  27. GRB 210120A: BALROG localization (Fermi Trigger 632819449 / GRB 210120299)
  28. GRB 210120A: Fermi GBM Final Real-time Localization
  29. GECAM detection of a short GRB 210119A or a new SGR candidate Swift J1851.2-6148
  30. GRB 210119A: Insight-HXMT/HE detection
  31. GRB 210119A: Fermi GBM observation
  32. Short Fermi GRB 210119A or new SGR Swift J1851.2-6148: Possible MASTER Short OT detection
  33. Fermi GRB 210119A: Global MASTER-Net observations report
  34. GRB 210119A: Fermi GBM Final Real-time Localization
  35. GRB 200613A: Host galaxy redshift from OSIRIS/GTC
  36. GRB 210104A: Late-time CAHA 2.2m detection
  37. Fermi trigger No 632573937: Global MASTER-Net observations report
  38. GRB 210104A: AstroSat CZTI detection
  39. GRB 210104A: Mondy optical observations, light curve
  40. GRB 210104A: Assy continued optical observations, correction to GCN circ. 29265
  41. GRB 210108A: BALROG localization (Fermi Trigger 631793415 / GRB 210108424)
  42. GRB 210104A: SAO RAS optical observations
  43. GRB 201227A: ASIM observation
  44. GRB210104A: VIRT optical transient detection.
  45. GRB 210104A: SARA-KP 0.9m Optical Afterglow Detection
  46. Fermi trigger No 631602681: Global MASTER-Net observations report
  47. GRB 210104A: CALET Gamma-Ray Burst Monitor detection
  48. Fermi trigger No 631584650: Global MASTER-Net observations report
  49. GRB 210104A: Assy continued optical observations
  50. Fermi GRB 210105A: Global MASTER-Net observations report
  51. GRB 210105A: Fermi GBM Final Real-time Localization
  52. Konus-Wind detection of GRB 210104A
  53. GRB 210104A: 1.3m DFOT Optical Afterglow Detection
  54. GRB 210104A: MASTER OT rebrightening detection
  55. GRB 210104A: Fermi GBM detection
  56. GRB 210104A: MITSuME Ishigaki optical observation
  57. Fermi GRB 210104A: Global MASTER-Net observations report
  58. GRB 210104A: Assy optical observations
  59. GRB 210104A: MITSuME Akeno optical observation
  60. GRB 210104A: BOOTES-4/MET early optical afterglow detection
  61. GRB 210104A: BALROG localization (Fermi Trigger 631452424 / GRB 210104477)
  62. GRB 210104A: Fermi GBM Final Real-time Localization
  63. Fermi GRB 210102C: Global MASTER-Net observations report
  64. GRB 210102C: Fermi GBM detection
  65. Fermi GRB 210101A: Global MASTER-Net observations report
  66. Fermi trigger No 631226368: Global MASTER-Net observations report
  67. Fermi trigger No 631119348: Global MASTER-Net observations report
  68. GRB 210101A: BALROG localization (Fermi Trigger 631205591 / GRB 210101620)
  69. GRB 210101A: Fermi GBM Final Real-time Localization
  70. Fermi trigger No 631113166: 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: GRAWITA VST-ESO PARANAL observations
  74. GRB 201227A: Fermi GBM observation
  75. Fermi GRB 201229B: Global MASTER-Net observations report
  76. GRB 201229B: BALROG localization (Fermi Trigger 630948017 / GRB 201229639)
  77. GRB 201229B: Fermi GBM Final Real-time Localization
  78. GRB 201020B: Assy, Koshka, Mondy and Maidanak optical observations
  79. Fermi GRB 201228B: Global MASTER-Net observations report
  80. GRB 201228B: Fermi GBM Final Real-time Localization
  81. GRB 201227A: Insight-HXMT/HE detection
  82. GRB 201226A: Insight-HXMT/HE detection
  83. GRB 201228A: Fermi GBM Final Real-time Localization
  84. IPN triangulation of GRB 201227A (short)
  85. GRB 201227A: AGILE detection of a burst
  86. Fermi trigger No 630681391: Global MASTER-Net observations report
  87. GRB 201223A: 1.3m DFOT and 1.04m ST optical observations
  88. GRB 201223A: Fermi GBM Detection
  89. GRB 201221A: Konus-Wind detection and joint Konus-Wind + Swift-BAT spectral analysis
  90. GRB 201221B: Insight-HXMT/HE detection
  91. Fermi trigger No 630389391: Global MASTER-Net observations report
  92. Fermi GRB 201222B: Global MASTER-Net observations report
  93. GRB 201221D: Fermi GBM detection
  94. Fermi-LAT Gamma-ray Observations of IceCube-201222A
  95. Fermi-LAT Gamma-ray Observations of IceCube-201221A
  96. IceCube-201222A: not observable by Fermi-GBM
  97. GRB 201222B: BALROG localization (Fermi Trigger / GRB 201222461)
  98. GRB 201222B: Fermi GBM Final Real-time Localization
  99. Fermi GRB 201221E: Global MASTER-Net observations report
  100. IceCube-201222A: IceCube observation of a high-energy neutrino candidate event

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