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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"

37753 results found.

  1. GRB 231030A: Fermi GBM Final Real-time Localization
  2. GRID detection of GRB 231020A
  3. GRB 231028A: AstroSat CZTI detection
  4. GRB 231028A: Glowbug gamma-ray detection
  5. GRB 231028A: Fermi GBM Detection
  6. Fermi trigger No 720224759: Global MASTER-Net observations report
  7. Swift GRB 231028A: Global MASTER-Net observations report
  8. GRB 231028A: Swift detection of a burst
  9. GRB 231028A: Fermi GBM Final Real-time Localization
  10. IceCube-231027A - IceCube observation of a high-energy neutrino candidate track-like event
  11. GRB 231019A: Glowbug gamma-ray detection
  12. GRB 231025A: Fermi GBM Observation
  13. GRB 231024A: Fermi GBM Observation
  14. GRB 231025A: Swift/BAT-GUANO detection of a likely short burst
  15. GRB 231025A: Fermi GBM Final Localization
  16. GRB 231024A: X-shooter spectroscopy of AT2023vuc/GOTO23baj reveals a young supernova with flash ionisation features
  17. GRB 231024A: LCOGT and ZTF detections of the GOTO optical counterpart candidate
  18. GRB 231020A: AstroSat CZTI detection
  19. GRB 231020B: AstroSat CZTI detection
  20. GRB 231024A: GOTO optical counterpart candidate
  21. GRB 231024A: Fermi GBM Final Localization
  22. Fermi trigger No 719846439: Global MASTER-Net observations report
  23. GRB 231018A: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  24. LIGO/Virgo/KAGRA S231020bw: Upper limits from Swift/BAT-GUANO
  25. GRB 231020A: Fermi GBM Detection
  26. GRID detection of GRB 231004A
  27. GRB 231017A: Mondy optical observations. A possible candidate for an afterglow or host galaxy.
  28. GRB 231019A: VZLUSAT-2 detection
  29. GRB 231018A: VZLUSAT-2 detection
  30. GRB 231020B: BALROG localization (Fermi Trigger 719530557 / GRB 231020900)
  31. GRB 231020B: Fermi GBM Final Real-time Localization
  32. GRB 231020A: BALROG localization (Fermi Trigger / GRB 231020790)
  33. LIGO/Virgo/KAGRA S231020ba: Upper limits from Fermi-GBM Observations
  34. GRB 231015A: NuSTAR Detection of Prompt Emission
  35. Fermi GRB 231020A: Global MASTER-Net observations report
  36. GRB 231020A: Fermi GBM Final Real-time Localization
  37. GRB 231012A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705709044)
  38. GRB 231017A: 1.3m DFOT Optical upper limit
  39. IceCube-231004A: Upper limits from Fermi-GBM Observations
  40. GRB 231018A: GRBAlpha detection
  41. GRB 231018A: CALET Gamma-Ray Burst Monitor detection
  42. Fermi GRB 231019A: Global MASTER-Net observations report
  43. GRB 231018A: Glowbug gamma-ray detection
  44. Konus-Wind detection of GRB 231018A
  45. IPN triangulation of GRB 231018A
  46. GRB 231017A: Swift/UVOT Upper Limit
  47. GRB 230911C: ATCA detection of possible radio counterpart
  48. GRB 231019A: Fermi GBM Final Real-time Localization
  49. GRB 231017A: GOTO optical upper limits
  50. GRB 231017A: JinShan optical upper limit
  51. GRB 231018A: GROWTH-India Follow-Up of a Fermi Long GRB
  52. GRB 231017A: Las Cumbres optical upper limit
  53. GRB 231015A: Glowbug gamma-ray detection
  54. GRB 231017A: LCOGT Optical Upper Limits
  55. GRB231017A: GROWTH-India upper limits on the optical afterglow
  56. GRB 231015A: AstroSat CZTI detection
  57. GRB 231018A: Fermi GBM Detection
  58. GRB 231017A: Fermi GBM Detection
  59. GRB 231017A: Swift-XRT observations
  60. GRB 231012B may not be a GRB
  61. GRB 231018A: BALROG localization (Fermi Trigger / GRB 231018521)
  62. GRB 231018A: Fermi GBM Final Real-time Localization
  63. GRB 231017A: Swift ToO observations
  64. GRB 231017A: Swift/BAT-GUANO candidate arcminute localization of a burst
  65. Fermi-LAT gamma-ray observations of IceCube-231014A
  66. GRB231017A: Fermi GBM Final Localization
  67. LIGO/Virgo/KAGRA S231014r: Upper limits from Swift/BAT-GUANO
  68. IceCube-231014A - IceCube observation of a high-energy neutrino candidate track-like event
  69. Correction in GCN 34814: GRB 231012B (not GRB 231012A)
  70. GRB 231012A: Fermi GBM Final Real-time Localization
  71. GRB 231012A: Fermi GBM Final Real-time Localization
  72. GRB 231004A: Glowbug gamma-ray detection
  73. LIGO/Virgo/KAGRA S231005j: Upper limits from Swift/BAT-GUANO
  74. GRB 231004A: CALET Gamma-Ray Burst Monitor detection
  75. Fermi-LAT gamma-ray observations of IceCube-231004A
  76. IceCube-231004A - IceCube observation of a high-energy neutrino candidate track-like event
  77. GRB 231004A: Fermi GBM Final Real-time Localization
  78. GRB 231003A is not a GRB
  79. GRB 231003A: Fermi GBM Final Real-time Localization
  80. LIGO/Virgo/KAGRA S231001aq: Upper limits from Swift/BAT-GUANO
  81. LIGO/Virgo/KAGRA S230930al: Upper limits from Swift/BAT-GUANO
  82. LIGO/Virgo/KAGRA S230928cb: Upper limits from Swift/BAT-GUANO
  83. GRB 230827B: 10.4m GTC spectroscopic redshift
  84. GRB 230930A: Fermi GBM Final Real-time Localization
  85. AT2023sva / GRB230916B: GIT observations of the afterglow
  86. transient AT2023sva: A Binary Driven Hypernova with a possible associated supernova
  87. Konus-Wind detection of GRB 230919A
  88. LIGO/Virgo/KAGRA S230924an: Upper limits from Swift/BAT-GUANO
  89. LIGO/Virgo/KAGRA S230920al: Upper limits from Swift/BAT-GUANO
  90. LIGO/Virgo/KAGRA S230919bj: Upper limits from Swift/BAT-GUANO
  91. Fermi Gamma-ray Burst Monitor trigger 717299390/230925076 is not a GRB
  92. Fermi Gamma-ray Burst Monitor trigger 230925241/717313591 is not a GRB
  93. GRB 230812B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
  94. GRB 230921A: Fermi GBM Final Real-time Localization
  95. GRB 230918B: VLT/X-shooter classification of AT 2023tbf (GOTO23aky) as a dwarf nova
  96. IPN triangulation of GRB 230919A (short)
  97. GRB 230919A: Fermi GBM Observation
  98. Correction to Fermi GBM Statement for Trigger 716527670/230916144
  99. Fermi GBM Statement for Trigger 716527670/230916144
  100. GRB 230919A: Swift/BAT-GUANO detection of a possibly short burst outside the coded FOV

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