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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"

11632 results found.

  1. Fermi GRB 231030B: Global MASTER-Net observations report
  2. IPN triangulation of GRB 231020A
  3. GRB 231030B: BALROG localization (Fermi Trigger 720388704 / GRB 231030832)
  4. GRB 231030B: Fermi GBM Final Real-time Localization
  5. GRB 231024A: AKO Optical Counterpart Candidate
  6. GRB 231028A: CALET Gamma-Ray Burst Monitor detection
  7. Fermi GRB 231030A: Global MASTER-Net observations report
  8. GRB 231030A: Fermi GBM Final Real-time Localization
  9. GRID detection of GRB 231020A
  10. GRB 231028A: AstroSat CZTI detection
  11. GRB 231028A: Glowbug gamma-ray detection
  12. GRB 231028A: Fermi GBM Detection
  13. Fermi trigger No 720224759: Global MASTER-Net observations report
  14. GRB 231028A: Swift detection of a burst
  15. GRB 231028A: Fermi GBM Final Real-time Localization
  16. IceCube-231027A - IceCube observation of a high-energy neutrino candidate track-like event
  17. GRB 231019A: Glowbug gamma-ray detection
  18. GRB 231025A: Fermi GBM Observation
  19. GRB 231024A: Fermi GBM Observation
  20. GRB 231025A: Swift/BAT-GUANO detection of a likely short burst
  21. GRB 231025A: Fermi GBM Final Localization
  22. GRB 231024A: X-shooter spectroscopy of AT2023vuc/GOTO23baj reveals a young supernova with flash ionisation features
  23. GRB 231024A: LCOGT and ZTF detections of the GOTO optical counterpart candidate
  24. GRB 231020A: AstroSat CZTI detection
  25. GRB 231020B: AstroSat CZTI detection
  26. GRB 231024A: GOTO optical counterpart candidate
  27. GRB 231024A: Fermi GBM Final Localization
  28. Fermi trigger No 719846439: Global MASTER-Net observations report
  29. GRB 231018A: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  30. GRB 231020A: Fermi GBM Detection
  31. GRID detection of GRB 231004A
  32. GRB 231017A: Mondy optical observations. A possible candidate for an afterglow or host galaxy.
  33. GRB 231019A: VZLUSAT-2 detection
  34. GRB 231018A: VZLUSAT-2 detection
  35. GRB 231020B: BALROG localization (Fermi Trigger 719530557 / GRB 231020900)
  36. GRB 231020B: Fermi GBM Final Real-time Localization
  37. GRB 231020A: BALROG localization (Fermi Trigger / GRB 231020790)
  38. LIGO/Virgo/KAGRA S231020ba: Upper limits from Fermi-GBM Observations
  39. Fermi GRB 231020A: Global MASTER-Net observations report
  40. GRB 231020A: Fermi GBM Final Real-time Localization
  41. GRB 231012A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705709044)
  42. GRB 231017A: 1.3m DFOT Optical upper limit
  43. IceCube-231004A: Upper limits from Fermi-GBM Observations
  44. GRB 231018A: GRBAlpha detection
  45. GRB 231018A: CALET Gamma-Ray Burst Monitor detection
  46. Fermi GRB 231019A: Global MASTER-Net observations report
  47. GRB 231018A: Glowbug gamma-ray detection
  48. Konus-Wind detection of GRB 231018A
  49. IPN triangulation of GRB 231018A
  50. GRB 231017A: Swift/UVOT Upper Limit
  51. GRB 231019A: Fermi GBM Final Real-time Localization
  52. GRB 231017A: GOTO optical upper limits
  53. GRB 231017A: JinShan optical upper limit
  54. GRB 231018A: GROWTH-India Follow-Up of a Fermi Long GRB
  55. GRB 231017A: Las Cumbres optical upper limit
  56. GRB 231017A: LCOGT Optical Upper Limits
  57. GRB231017A: GROWTH-India upper limits on the optical afterglow
  58. GRB 231018A: Fermi GBM Detection
  59. GRB 231017A: Fermi GBM Detection
  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/BAT-GUANO candidate arcminute localization of a burst
  64. Fermi-LAT gamma-ray observations of IceCube-231014A
  65. GRB231017A: Fermi GBM Final Localization
  66. IceCube-231014A - IceCube observation of a high-energy neutrino candidate track-like event
  67. Correction in GCN 34814: GRB 231012B (not GRB 231012A)
  68. GRB 231012A: Fermi GBM Final Real-time Localization
  69. GRB 231012A: Fermi GBM Final Real-time Localization
  70. GRB 231004A: Glowbug gamma-ray detection
  71. GRB 231004A: CALET Gamma-Ray Burst Monitor detection
  72. Fermi-LAT gamma-ray observations of IceCube-231004A
  73. IceCube-231004A - IceCube observation of a high-energy neutrino candidate track-like event
  74. GRB 231004A: Fermi GBM Final Real-time Localization
  75. GRB 231003A is not a GRB
  76. GRB 231003A: Fermi GBM Final Real-time Localization
  77. GRB 230827B: 10.4m GTC spectroscopic redshift
  78. GRB 230930A: Fermi GBM Final Real-time Localization
  79. AT2023sva / GRB230916B: GIT observations of the afterglow
  80. transient AT2023sva: A Binary Driven Hypernova with a possible associated supernova
  81. Konus-Wind detection of GRB 230919A
  82. Fermi Gamma-ray Burst Monitor trigger 717299390/230925076 is not a GRB
  83. Fermi Gamma-ray Burst Monitor trigger 230925241/717313591 is not a GRB
  84. GRB 230812B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
  85. GRB 230921A: Fermi GBM Final Real-time Localization
  86. GRB 230918B: VLT/X-shooter classification of AT 2023tbf (GOTO23aky) as a dwarf nova
  87. IPN triangulation of GRB 230919A (short)
  88. GRB 230919A: Fermi GBM Observation
  89. Correction to Fermi GBM Statement for Trigger 716527670/230916144
  90. Fermi GBM Statement for Trigger 716527670/230916144
  91. GRB 230919A: Swift/BAT-GUANO detection of a possibly short burst outside the coded FOV
  92. GRB 230812B : optical observations from MISTRAL at Observatoire de Haute-Provence
  93. GRB 230919A: AstroSat CZTI detection
  94. AT2023sva: redshift from OSIRIS+/GTC of the ZTF afterglow
  95. GRB 230918B: GOTO detection of a fast-rising transient in the GBM localisation region
  96. GRB 230919A: Fermi GBM Final Real-time Localization
  97. Detection of self-absorbed radio emission from GRB 230812B with the JVLA + uGMRT
  98. GRB 230918B: Fermi GBM Final Real-time Localization
  99. GRB 230918A (short): Glowbug gamma-ray detection
  100. GRB 230916B: Glowbug gamma-ray detection

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