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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"

32710 results found.

  1. GRB 220423A: Detection by VZLUSAT-2
  2. Konus-Wind detection of GRB 220427A
  3. GRB 220427A: Swift-XRT refined Analysis
  4. GRB 220426A: Tiled Swift observations
  5. Konus-Wind detection of GRB 220426A
  6. IPN triangulation of GRB 220426A
  7. Fermi GRB 220426A: Global MASTER-Net observations report
  8. GRB 220426A: Swift/BAT-GUANO detection outside the coded FOV
  9. Fermi-LAT Gamma-ray Observations of IceCube-220425A
  10. Fermi GRB 220426B: Global MASTER-Net observations report
  11. Correction to 31937: GRB 220421B: Detection by VZLUSAT-2
  12. IceCube-220425A: MASTER: flaring blazar TXS 1742-078 as the possible neutrino source candidate
  13. Fermi-LAT Gamma-ray Observations of IceCube-220424A
  14. GRB 220423A: Swift/BAT-GUANO detection outside the coded FOV
  15. GRB 220421A: Fermi GBM observation
  16. Fermi-LAT Gamma-ray Observations of IceCube-220421A
  17. GRB 220418B Fermi GBM observation
  18. “GRB 220420A” is not a GRB
  19. GRB 220403C: Further Swift-XRT observations
  20. GRB 220418B: Swift ToO observations
  21. GRB 220417A: Fermi GBM detection
  22. GRB 220418B: Swift/BAT-GUANO refined location of a short burst
  23. IPN triangulation of GRB 220411A
  24. GRB 220418B: Swift/BAT-GUANO candidate arcminute localization of a short burst
  25. GRB 220417A: Swift/BAT-GUANO detection outside the coded FOV
  26. GRB 220412B: Swift/UVOT Upper Limits
  27. Fermi GRB 220418A: Global MASTER-Net observations report
  28. Fermi GRB 220417A: Global MASTER-Net observations report
  29. GRB 220412B: Swift-BAT refined analysis
  30. Konus-Wind detection of GRB 220412B
  31. GRB 220412B: Fermi GBM observation
  32. Konus-Wind detection of GRB 220403C
  33. GRB 220408B: Fermi GBM observation
  34. Konus-Wind detection of GRB 220408B
  35. GRB 220412B: TNG optical observations
  36. GRB 220412A: GRANDMA observations
  37. GRB 220412A: Continued RATIR Observations and Steepening of the Light Curve
  38. GRB 220412A: Swift-BAT refined analysis
  39. GRB 220412A: RATIR Observations of the Fading Afterglow
  40. GRB 220412B: Swift-XRT observations
  41. GRB 220408B: Fermi-LAT detection
  42. IPN triangulation of short/soft GRB 220406A
  43. Swift GRB 220412B: Global MASTER-Net observations report
  44. GRB 220408A: HCT optical upper limit
  45. GRB 220412B: GIT optical upper limit
  46. GRB 220412A: MITSuME Akeno optical upper limits
  47. Correction to GCN 31888: GRB 220412A: Swift-XRT refined Analysis
  48. GRB 220412B: MITSuME Akeno optical upper limits
  49. GRB 220412A: Swift-XRT refined Analysis
  50. GRB 220412A: Swift/UVOT Upper Limits
  51. GRB 220403B: GRANDMA observations
  52. GRB 220412A: RATIR Afterglow Candidate
  53. GRB 220411A: AstroSat CZTI detection
  54. IPN triangulation of GRB 220408B
  55. IPN triangulation of GRB 220403C
  56. GRB 220403B: Swift/UVOT Detection
  57. GRB 220408A: Lowell Discovery Telescope Optical Observations
  58. GRB 220408A: Swift-BAT refined analysis
  59. Fermi GRB 220411A: Global MASTER-Net observations report
  60. GRB 220408A: RATIR Optical and NIR Observations
  61. GRB 220403B: 1.3m DFOT Optical upper limit
  62. GRB 220408A: 1.3m DFOT Optical upper limit
  63. GRB 220408A: LOAO, DOAO, and, SAO optical upper limit
  64. GRB 220403C: Swift-XRT observations
  65. GRB 220408A: redshift lower limit estimating
  66. GRB 220408A: NOT optical observations and archival detection
  67. GRB 220408B: AstroSat CZTI detection
  68. GRB 220408A: LCO Optical Afterglow Detection
  69. GRB 220408A: Swift-XRT refined Analysis
  70. GRB 220403C: Swift ToO observations
  71. Fermi GRB 220408B: Global MASTER-Net observations report
  72. GRB 220408A: GIT optical upper limit
  73. GRB 220408A: Fermi GBM observation
  74. GRB 220408A: Swift/UVOT Detection
  75. GRB 220408A: Xinglong-2.16m optical upper limit
  76. Chandra upper limit at the location of GRB 220408A
  77. GRB 220408A: KAIT Optical Observations
  78. Fermi GRB 220408A: Global MASTER-Net observations report
  79. ZTF22aaajecp/AT2022cmc: continued optical observations (Mondy, SAO RAS, CrAO)
  80. Fermi-LAT Gamma-ray Observations of IceCube-220405B
  81. GRB 220403B: Mondy optical upper limit
  82. IceCube-220405A: No Candidate Counterparts from the Zwicky Transient Facility
  83. IceCube-220405B: No Candidate Counterparts from the Zwicky Transient Facility
  84. GRB 220404A: Swift-BAT refined analysis
  85. GRB 220403B: Kitab optical observations
  86. Fermi-LAT Gamma-ray Observations of IceCube-220405A
  87. GRB 220403B: Swift-BAT refined analysis
  88. GRB 220403B: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  89. GRB 220403B: Fermi GBM detection
  90. GRB 220403B: Swift-XRT refined Analysis
  91. GRB 220403B: LBT observations
  92. Swift GRB 220403B: Global MASTER-Net observations report
  93. GRB 220403C (or A): Swift/BAT-GUANO detection outside the coded FOV
  94. GRB 220403B: Nanshan/NEXT optical afterglow power-law decay
  95. GRB 220403A: Tautenburg observations
  96. Fermi GRB 220403A: Global MASTER-Net observations report
  97. GRB 220401A: Swift/BAT-GUANO detection outside the coded FOV
  98. GRB 220401A: Fermi GBM observation
  99. Fermi GRB 220401B: Global MASTER-Net observations report
  100. Fermi Gamma-ray Burst Monitor trigger 220331776/670444627 is not a GRB

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