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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"

22195 results found.

  1. Transient EPW20240219aa: Optical observations with LDT
  2. GRB 240225B: Swift-XRT afterglow detection
  3. Fermi trigger No 731161136: Global MASTER-Net observations report
  4. Swift GRB 240303A: Global MASTER-Net observations report
  5. Swift J151857.0-572147: Confirmation of a new galactic transient
  6. GRB 240215A: Swift-XRT afterglow detection
  7. GRB 240218A: NOEMA upper limit
  8. GRB 240225B: further SAO RAS optical observations
  9. Fermi GRB 240229A: Global MASTER-Net observations report
  10. IceCube Alert 240229.66: Global MASTER-Net observations report
  11. GRB 240225B: Swift ToO observations
  12. Konus-Wind detection of GRB 240225B (long)
  13. GRB 240225B: 3.6m DOT observation
  14. GRB 240225B: WINTER near-IR observations and upper limits
  15. GRB 240225B: SAO RAS optical observations
  16. GRB 240225B: Mondy afterglow observations
  17. Fermi GRB 240227A: Global MASTER-Net observations report
  18. GRB 240225B: Liverpool Telescope afterglow observations
  19. GRB 240225B: Liverpool Telescope optical afterglow observations
  20. GRB 240225B: NOT optical observations
  21. GRB 240218A: CMO SAI NIR upper limit
  22. Fermi GRB 240226A: Global MASTER-Net observations report
  23. GRB 240225B: Swift-XRT observations
  24. Transient EPW20240219aa: Kp-band imaging observations with NIRES
  25. Transient EPW20240219aa: J-band upper limits from WINTER
  26. GRB 240225B: GOTO detection of a candidate optical afterglow
  27. Transient EPW20240219aa: REM optical/NIR upper limits
  28. GRB 240222A: ATCA radio observations
  29. Fermi trigger No 730618809: Global MASTER-Net observations report
  30. GRB 240225B: Tiled Swift observations
  31. GRB 240218A: VLA detection
  32. GRB 240225A: Swift/BAT-GUANO detection of a short burst
  33. Transient EPW20240219aa: 7DT Optical Upper Limits
  34. VLA X-band observation of EPW20240219aa
  35. Transient EPW20240219aa: Mondy optical observations
  36. Transient EPW20240219aa: upper limit in gamma-ray range from SPI-ACS/INTEGRAL observations
  37. GRB 240222A: Swift/UVOT Upper Limits
  38. Swift GRB 240222A: Global MASTER-Net observations report
  39. Fermi GRB 240222A: Global MASTER-Net observations report
  40. GRB 240222A: REM optical and NIR early-time observations
  41. Swift GRB240221.92: Global MASTER-Net observations report
  42. GRB 240218A: MeerLICHT upper limits
  43. GRB 240218A: LBT H-band detection
  44. Fermi GRB 240220A: Global MASTER-Net observations report
  45. Konus-Wind detection of GRB 240218A
  46. Fermi trigger No 729914426: Global MASTER-Net observations report
  47. GRB 240218A: VLT/FORS2 z-band detection
  48. GRB 240218A: REM detection of a NIR afterglow candidate
  49. Gamma-ray flaring activity from the blazar 1ES 1959+650 observed by the Fermi-LAT
  50. Swift GRB240218.08: Global MASTER-Net observations report
  51. GRB 240215B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  52. Fermi GRB 240216A: Global MASTER-Net observations report
  53. Fermi trigger No 729719508: Global MASTER-Net observations report
  54. GRB 240215A: Tiled Swift observations
  55. GRB 240215A: Swift/BAT-GUANO localization of a burst
  56. Fermi trigger No 729703985: Global MASTER-Net observations report
  57. Fermi trigger No 729650855: Global MASTER-Net observations report
  58. GRB 240209A: Classification of AT2024cew/GOTO24pw as Type Ia-pec supernova
  59. GRB 240209A: Fermi GBM observation
  60. The AGILE satellite ceased operations and re-entered today into the atmosphere
  61. The AGILE satellite ceased operations and re-entered today into the atmosphere
  62. GRB240209A: OHP/T193 detection of the GOTO afterglow candidate AT2024cew / GOTO24pw
  63. GRB 240209A: Wendelstein Optical Observations
  64. GRB 240128A: Further Swift-XRT observations
  65. GRB 240214A: Tiled Swift observations
  66. GRB 240214A/1H 0451-560: MAXI/GSC detection
  67. Fermi GRB 240213A: Global MASTER-Net observations report
  68. GRB 240209A: NOEMA non-detection of AT2024cew / GOTO24pw counterpart candidate
  69. GRB 240209A: NOT photometry of the AT2024cew / GOTO24pw counterpart candidate
  70. GRB 240209A: GOTO optical counterpart candidate
  71. Konus-Wind detection of GRB 240205A (short)
  72. Fermi trigger No 729152364: Global MASTER-Net observations report
  73. Fermi-LAT gamma-ray observations of IceCube-240204A
  74. GRB 240205B: PRIME near infrared detection
  75. GRB240204A: Swift/UVOT Upper Limits
  76. Fermi trigger No 729012023: Global MASTER-Net observations report
  77. Konus-Wind detection of GRB 240205B (long / very soft)
  78. GRB 240205B: VLT/X-shooter redshift
  79. GRB 240205B: BOOTES-6 optical afterglow follow-up
  80. GRB 240205B: ATCA detection of radio counterpart
  81. GRB 240205B: REM detection of the optical/NIR afterglow
  82. GRB 240204A: Mondy optical afterglow observations
  83. GRB 240204A : OHP/T193/T120 optical afterglow fading detection
  84. GRB 240205B: Skynet Optical Afterglow Observations
  85. GRB 240205B: BOOTES-7 optical afterglow follow-up
  86. Fermi trigger No 728749569: Global MASTER-Net observations report
  87. GRB 240205B: MASTER OT J232550.14-550704.6 counterpart detection
  88. GRB 240205B: Swift detection of a burst
  89. Swift GRB240205.93: Global MASTER-Net observations report
  90. GRB 240204a: Liverpool Telescope optical afterglow detection
  91. GRB 240204A: Osservatorio Astronomico Nastro Verde upper limit
  92. Fermi trigger No 728796365: Global MASTER-Net observations report
  93. GRB 240204A: Montarrenti Observatory optical observations
  94. Fermi GRB 240204A: Global MASTER-Net observations report
  95. Fermi trigger No 728706420: Global MASTER-Net observations report
  96. IceCube Alert 240204.38: Global MASTER-Net observations report
  97. GRB 240129A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  98. GRB 240128A: Swift-XRT observations
  99. GRB 240128A: Tiled Swift observations
  100. Fermi GRB 240127A: Global MASTER-Net observations report

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