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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"

37764 results found.

  1. GRB 231030B: Fermi GBM Detection
  2. GRB 231030B: AstroSat CZTI detection
  3. Fermi GRB 231030B: Global MASTER-Net observations report
  4. IPN triangulation of GRB 231020A
  5. GRB 231030B: BALROG localization (Fermi Trigger 720388704 / GRB 231030832)
  6. GRB 231030B: Fermi GBM Final Real-time Localization
  7. GRB 231028A: Swift-BAT refined analysis
  8. LIGO/Virgo/KAGRA S231029y: Upper limits from Swift/BAT-GUANO
  9. GRB 231024A: AKO Optical Counterpart Candidate
  10. GRB 231028A: CALET Gamma-Ray Burst Monitor detection
  11. Fermi GRB 231030A: Global MASTER-Net observations report
  12. GRB 231030A: Fermi GBM Final Real-time Localization
  13. GRID detection of GRB 231020A
  14. GRB 231028A: AstroSat CZTI detection
  15. GRB 231028A: Glowbug gamma-ray detection
  16. GRB 231028A: Fermi GBM Detection
  17. Fermi trigger No 720224759: Global MASTER-Net observations report
  18. Swift GRB 231028A: Global MASTER-Net observations report
  19. GRB 231028A: Swift detection of a burst
  20. GRB 231028A: Fermi GBM Final Real-time Localization
  21. IceCube-231027A - IceCube observation of a high-energy neutrino candidate track-like event
  22. GRB 231019A: Glowbug gamma-ray detection
  23. GRB 231025A: Fermi GBM Observation
  24. GRB 231024A: Fermi GBM Observation
  25. GRB 231025A: Swift/BAT-GUANO detection of a likely short burst
  26. GRB 231025A: Fermi GBM Final Localization
  27. GRB 231024A: X-shooter spectroscopy of AT2023vuc/GOTO23baj reveals a young supernova with flash ionisation features
  28. GRB 231024A: LCOGT and ZTF detections of the GOTO optical counterpart candidate
  29. GRB 231020A: AstroSat CZTI detection
  30. GRB 231020B: AstroSat CZTI detection
  31. GRB 231024A: GOTO optical counterpart candidate
  32. GRB 231024A: Fermi GBM Final Localization
  33. Fermi trigger No 719846439: Global MASTER-Net observations report
  34. GRB 231018A: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  35. LIGO/Virgo/KAGRA S231020bw: Upper limits from Swift/BAT-GUANO
  36. GRB 231020A: Fermi GBM Detection
  37. GRID detection of GRB 231004A
  38. GRB 231017A: Mondy optical observations. A possible candidate for an afterglow or host galaxy.
  39. GRB 231019A: VZLUSAT-2 detection
  40. GRB 231018A: VZLUSAT-2 detection
  41. GRB 231020B: BALROG localization (Fermi Trigger 719530557 / GRB 231020900)
  42. GRB 231020B: Fermi GBM Final Real-time Localization
  43. GRB 231020A: BALROG localization (Fermi Trigger / GRB 231020790)
  44. LIGO/Virgo/KAGRA S231020ba: Upper limits from Fermi-GBM Observations
  45. GRB 231015A: NuSTAR Detection of Prompt Emission
  46. Fermi GRB 231020A: Global MASTER-Net observations report
  47. GRB 231020A: Fermi GBM Final Real-time Localization
  48. GRB 231012A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705709044)
  49. GRB 231017A: 1.3m DFOT Optical upper limit
  50. IceCube-231004A: Upper limits from Fermi-GBM Observations
  51. GRB 231018A: GRBAlpha detection
  52. GRB 231018A: CALET Gamma-Ray Burst Monitor detection
  53. Fermi GRB 231019A: Global MASTER-Net observations report
  54. GRB 231018A: Glowbug gamma-ray detection
  55. Konus-Wind detection of GRB 231018A
  56. IPN triangulation of GRB 231018A
  57. GRB 231017A: Swift/UVOT Upper Limit
  58. GRB 230911C: ATCA detection of possible radio counterpart
  59. GRB 231019A: Fermi GBM Final Real-time Localization
  60. GRB 231017A: GOTO optical upper limits
  61. GRB 231017A: JinShan optical upper limit
  62. GRB 231018A: GROWTH-India Follow-Up of a Fermi Long GRB
  63. GRB 231017A: Las Cumbres optical upper limit
  64. GRB 231015A: Glowbug gamma-ray detection
  65. GRB 231017A: LCOGT Optical Upper Limits
  66. GRB231017A: GROWTH-India upper limits on the optical afterglow
  67. GRB 231015A: AstroSat CZTI detection
  68. GRB 231018A: Fermi GBM Detection
  69. GRB 231017A: Fermi GBM Detection
  70. GRB 231017A: Swift-XRT observations
  71. GRB 231012B may not be a GRB
  72. GRB 231018A: BALROG localization (Fermi Trigger / GRB 231018521)
  73. GRB 231018A: Fermi GBM Final Real-time Localization
  74. GRB 231017A: Swift ToO observations
  75. GRB 231017A: Swift/BAT-GUANO candidate arcminute localization of a burst
  76. Fermi-LAT gamma-ray observations of IceCube-231014A
  77. GRB231017A: Fermi GBM Final Localization
  78. LIGO/Virgo/KAGRA S231014r: Upper limits from Swift/BAT-GUANO
  79. IceCube-231014A - IceCube observation of a high-energy neutrino candidate track-like event
  80. Correction in GCN 34814: GRB 231012B (not GRB 231012A)
  81. GRB 231012A: Fermi GBM Final Real-time Localization
  82. GRB 231012A: Fermi GBM Final Real-time Localization
  83. GRB 231004A: Glowbug gamma-ray detection
  84. LIGO/Virgo/KAGRA S231005j: Upper limits from Swift/BAT-GUANO
  85. GRB 231004A: CALET Gamma-Ray Burst Monitor detection
  86. Fermi-LAT gamma-ray observations of IceCube-231004A
  87. IceCube-231004A - IceCube observation of a high-energy neutrino candidate track-like event
  88. GRB 231004A: Fermi GBM Final Real-time Localization
  89. GRB 231003A is not a GRB
  90. GRB 231003A: Fermi GBM Final Real-time Localization
  91. LIGO/Virgo/KAGRA S231001aq: Upper limits from Swift/BAT-GUANO
  92. LIGO/Virgo/KAGRA S230930al: Upper limits from Swift/BAT-GUANO
  93. LIGO/Virgo/KAGRA S230928cb: Upper limits from Swift/BAT-GUANO
  94. GRB 230827B: 10.4m GTC spectroscopic redshift
  95. GRB 230930A: Fermi GBM Final Real-time Localization
  96. AT2023sva / GRB230916B: GIT observations of the afterglow
  97. transient AT2023sva: A Binary Driven Hypernova with a possible associated supernova
  98. Konus-Wind detection of GRB 230919A
  99. LIGO/Virgo/KAGRA S230924an: Upper limits from Swift/BAT-GUANO
  100. LIGO/Virgo/KAGRA S230920al: Upper limits from Swift/BAT-GUANO

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