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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"

28126 results found.

  1. GRB 240303B: Fermi GBM Detection
  2. GRB 240225B: Swift-XRT afterglow detection
  3. Swift detection of Swift J151857.0-572147
  4. Fermi trigger No 731161136: Global MASTER-Net observations report
  5. GRB 240303C: BALROG localization (Fermi Trigger 731189113 / GRB 240303837)
  6. GRB 240303B: BALROG localization (Fermi Trigger 731161136 / GRB 240303513)
  7. GRB 240303A: Swift detection of a burst
  8. GRB 240225B: Glowbug gamma-ray detection
  9. IceCube-240229A: Upper limits from a search for additional neutrino events in IceCube
  10. GRB 240225C: Glowbug gamma-ray detection
  11. GRB 240225A (short): Glowbug gamma-ray detection
  12. GRB 240229A: DDOTI Upper Limits on the Afterglow
  13. GRB 240218A: NOEMA upper limit
  14. GRB 240225B: further SAO RAS optical observations
  15. GRB 240229A: BALROG localization (Fermi Trigger 730908432 / GRB 240229588)
  16. GRB 240225B: VLT/X-shooter redshift
  17. GRB 240225B : MITSuME Akeno optical afterglow candidate detection
  18. GRB 240225B: 3.6m DOT observation
  19. GRB 240225B: WINTER near-IR observations and upper limits
  20. GRB 240225B: SAO RAS optical observations
  21. GRB 240225B: Mondy afterglow observations
  22. GRB 240218A: CMO SAI NIR upper limit
  23. GRB 240225B: Nanshan/HMT optical afterglow detection
  24. GRB 240225B: Swift-XRT observations
  25. Transient EPW20240219aa: Kp-band imaging observations with NIRES
  26. Transient EPW20240219aa: J-band upper limits from WINTER
  27. Transient EPW20240219aa: REM optical/NIR upper limits
  28. GRB 240225B: AstroSat CZTI detection
  29. GRB 240225B: MAXI/GSC detection
  30. Transient EPW20240219aa: Xinglong-2.16m optical upper limit
  31. GRB 240225A: Swift/BAT-GUANO detection of a short burst
  32. Transient EPW20240219aa: GECKO: LOAO Optical Upper Limits
  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. Insight-HXMT/HE Sub-Threshold Detection of Transient EPW20240219aa
  38. Transient EPW20240219aa: Liverpool Telescope non-detection and limiting magnitude
  39. GRB 240222A: GECAM detection of a burst
  40. GRB 240222A: Swift-BAT refined analysis
  41. GRB 240222A: Swift-XRT refined Analysis
  42. GRB 240222A: Fermi GBM Observation
  43. GRB 240222A: Swift/UVOT Upper Limits
  44. Fermi GBM Sub-Threshold Detection of EPW20240219aa as a likely GRB
  45. GRB 240222A: REM optical and NIR early-time observations
  46. GRB 240222A: Swift detection of a burst
  47. GRB 240218A: MeerLICHT upper limits
  48. GRB 240216A: Glowbug gamma-ray detection
  49. GRB 240215B: Fermi GBM Observation
  50. GRB 240218A: LBT H-band detection
  51. GRB 240218A: Swift-BAT refined analysis
  52. GRB 240218A: Swift-XRT refined Analysis
  53. GRB 240218A: VLT/X-shooter redshift of z = 6.782
  54. GRB 240218A: Fermi GBM Detection
  55. GRB 240215A: Fermi GBM Observation
  56. GRB 240218A: Enhanced Swift-XRT position
  57. GRB 240218A: REM detection of a NIR afterglow candidate
  58. GRB 240218A : r-band upper limit from Observatoire de Haute-Provence
  59. GRB240218A: VLT/X-shooter upper limits
  60. GRB 240218A: Swift detection of a burst
  61. GRB 240215B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  62. GRB 240215A: Swift/BAT-GUANO localization of a burst
  63. GRB 240213A: Glowbug gamma-ray detection
  64. GRB 240128A: Further Swift-XRT observations
  65. GRB 240214A/1H 0451-560: MAXI/GSC detection
  66. GRB 240213A: BALROG localization (Fermi Trigger / GRB 240213841)
  67. GRB 240209A: NOT photometry of the AT2024cew / GOTO24pw counterpart candidate
  68. GRB 240209A: GOTO optical counterpart candidate
  69. Konus-Wind detection of GRB 240204A
  70. IPN triangulation of GRB 240205A (short)
  71. Fermi-LAT gamma-ray observations of IceCube-240204A
  72. GRB 240205B: PRIME near infrared detection
  73. GRB 240205A (short): Glowbug gamma-ray detection
  74. GRB240204A: Swift/UVOT Upper Limits
  75. GRB 240205B: Swift-BAT refined analysis
  76. Konus-Wind detection of GRB 240205B (long / very soft)
  77. GRB 240205B: VLT/X-shooter redshift
  78. GRB 240205B: REM detection of the optical/NIR afterglow
  79. GRB 240205B: Fermi GBM Observation
  80. GRB 240204A : OHP/T193/T120 optical afterglow fading detection
  81. GRB 240205B: GECAM detection of a long burst
  82. GRB 240204A: Swift-BAT refined analysis
  83. GRB 240205B: Skynet Optical Afterglow Observations
  84. Fermi trigger No 728749569: Global MASTER-Net observations report
  85. GRB 240204A: Fermi GBM Observation
  86. GRB 240204a: Liverpool Telescope optical afterglow detection
  87. GRB 240204A: Osservatorio Astronomico Nastro Verde upper limit
  88. IceCube-240204A: Upper limits from a search for additional neutrino events in IceCube
  89. GRB 240204A: optical afterglow detection with LCOGT 1m telescopes at Sutherland and Teide Observatories
  90. GRB 240204A: Montarrenti Observatory optical observations
  91. GRB 240204A: Enhanced Swift-XRT position
  92. GRB 240204A: Mondy optical afterglow candidate
  93. GRB 240204A: Swift detection of a burst
  94. Konus-Wind detection of GRB 240123C
  95. IPN triangulation of GRB 240124B
  96. GRB 240129A: Fermi GBM Observation
  97. GRB 240129A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  98. GRB 240128A: Glowbug gamma-ray detection
  99. GRB 240128A: Swift-XRT observations
  100. GRB 240125A: GRBAlpha detection

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