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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"

36350 results found.

  1. IPN triangulation of GRB 231018A
  2. GRB 231017A: Swift/UVOT Upper Limit
  3. GRB 230911C: ATCA detection of possible radio counterpart
  4. GRB 231019A: Fermi GBM Final Real-time Localization
  5. GRB 231017A: GOTO optical upper limits
  6. GRB 231017A: JinShan optical upper limit
  7. GRB 231018A: GROWTH-India Follow-Up of a Fermi Long GRB
  8. GRB 231017A: Las Cumbres optical upper limit
  9. GRB 231015A: Glowbug gamma-ray detection
  10. GRB 231017A: LCOGT Optical Upper Limits
  11. GRB231017A: GROWTH-India upper limits on the optical afterglow
  12. GRB 231015A: AstroSat CZTI detection
  13. GRB 231018A: Fermi GBM Detection
  14. GRB 231017A: Fermi GBM Detection
  15. GRB 231017A: Swift-XRT observations
  16. GRB 231012B may not be a GRB
  17. GRB 231018A: BALROG localization (Fermi Trigger / GRB 231018521)
  18. GRB 231018A: Fermi GBM Final Real-time Localization
  19. GRB 231017A: Swift ToO observations
  20. GRB 231017A: Swift/BAT-GUANO candidate arcminute localization of a burst
  21. GRB231017A: Fermi GBM Final Localization
  22. IceCube-231014A: Upper limits from a search for additional neutrino events in IceCube
  23. LIGO/Virgo/KAGRA S231014r: Upper limits from Swift/BAT-GUANO
  24. Correction in GCN 34814: GRB 231012B (not GRB 231012A)
  25. GRB 231012A: Fermi GBM Final Real-time Localization
  26. GRB 231012A: Fermi GBM Final Real-time Localization
  27. GRB 231004A: Glowbug gamma-ray detection
  28. LIGO/Virgo/KAGRA S231005j: Upper limits from Swift/BAT-GUANO
  29. IceCube-231004A: Upper limits from a search for additional neutrino events in IceCube
  30. GRB 231004A: CALET Gamma-Ray Burst Monitor detection
  31. Update of IceCube-231004A - Corrected direciton
  32. GRB 231004A: Fermi GBM Final Real-time Localization
  33. GRB 231003A is not a GRB
  34. GRB 231003A: Fermi GBM Final Real-time Localization
  35. LIGO/Virgo/KAGRA S231001aq: Upper limits from Swift/BAT-GUANO
  36. LIGO/Virgo/KAGRA S230930al: Upper limits from Swift/BAT-GUANO
  37. LIGO/Virgo/KAGRA S230928cb: Upper limits from Swift/BAT-GUANO
  38. GRB 230827B: 10.4m GTC spectroscopic redshift
  39. GRB 230930A: Fermi GBM Final Real-time Localization
  40. AT2023sva / GRB230916B: GIT observations of the afterglow
  41. transient AT2023sva: A Binary Driven Hypernova with a possible associated supernova
  42. Swift Triggers 1192740, 1192742 and 1192743 are not astrophysical events
  43. Konus-Wind detection of GRB 230919A
  44. LIGO/Virgo/KAGRA S230924an: Upper limits from Swift/BAT-GUANO
  45. LIGO/Virgo/KAGRA S230920al: Upper limits from Swift/BAT-GUANO
  46. LIGO/Virgo/KAGRA S230919bj: Upper limits from Swift/BAT-GUANO
  47. Fermi Gamma-ray Burst Monitor trigger 717299390/230925076 is not a GRB
  48. Fermi Gamma-ray Burst Monitor trigger 230925241/717313591 is not a GRB
  49. GRB 230812B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
  50. GRB 230921A: Fermi GBM Final Real-time Localization
  51. GRB 230918B: VLT/X-shooter classification of AT 2023tbf (GOTO23aky) as a dwarf nova
  52. IPN triangulation of GRB 230919A (short)
  53. GRB 230919A: Fermi GBM Observation
  54. Fermi GBM Statement for Trigger 716527670/230916144
  55. GRB 230919A: Swift/BAT-GUANO detection of a possibly short burst outside the coded FOV
  56. GRB 230812B : optical observations from MISTRAL at Observatoire de Haute-Provence
  57. GRB 230919A: AstroSat CZTI detection
  58. AT2023sva: redshift from OSIRIS+/GTC of the ZTF afterglow
  59. GRB 230918B: GOTO detection of a fast-rising transient in the GBM localisation region
  60. GRB 230919A: Fermi GBM Final Real-time Localization
  61. Detection of self-absorbed radio emission from GRB 230812B with the JVLA + uGMRT
  62. GRB 230918B: Fermi GBM Final Real-time Localization
  63. GRB 230918A (short): Glowbug gamma-ray detection
  64. GRB 230916B: Glowbug gamma-ray detection
  65. ZTF and SEDM Observations of the Candidate Optical Afterglow AT 2023sva
  66. GRB 230915A: Fermi GBM observation
  67. GRB 230812B: Radio observations with the uGMRT
  68. GRB 230918A: Fermi GBM Final Real-time Localization
  69. GRB 230917A: AstroSat CZTI detection
  70. GRB 230915B: Glowbug gamma-ray detection
  71. GRB 230916A: NuSTAR Discovery of Prompt Emission from a Potential GRB
  72. GRB 230911A: Fermi GBM Observation
  73. GRB 230915A: Swift/BAT-GUANO detection of a burst
  74. LIGO/Virgo/KAGRA S230914ak: Upper limits from Swift/BAT-GUANO
  75. GRB 230911D: GRBAlpha detection
  76. Swift Trigger 1192233 is not a GRB
  77. GRB 230906A: optical counterpart
  78. IceCube-230914A: Upper limits from a search for additional neutrino events in IceCube
  79. GRB 230911A: Swift-XRT afterglow detection
  80. GRB 230913A: CALET Gamma-Ray Burst Monitor detection
  81. GRB 230913A: Glowbug gamma-ray detection
  82. GRB 230812B: Bad Time Intervals for Fermi GBM data
  83. GRB 230913A: Fermi GBM Observation
  84. Swift Trigger 1191904 is not a GRB
  85. GRB 230911A: Swift ToO observations
  86. GRB 230913A: Swift/BAT-GUANO arcminute localization of a burst
  87. Fermi GRB 230913A: Global MASTER-Net observations report
  88. GRB 230911A: GOTO optical counterpart candidate
  89. GRB 230913A: Fermi GBM Final Real-time Localization
  90. GRB 230908A: CALET Gamma-Ray Burst Monitor detection
  91. GRB 230911D: NuSTAR Detection of Prompt Emission
  92. GRB 230911B: AstroSat CZTI detection
  93. GRB 230911C: Swift-XRT refined Analysis
  94. GRB 230911C: Swift-BAT refined analysis
  95. GRB230911C: BOOTES-6/DPRT optical upper limit
  96. GRB 230906A: Chandra detection of the X-ray afterglow
  97. Swift GRB 230911C: Global MASTER-Net observations report
  98. GRB 230911D: Fermi GBM observation
  99. IPN triangulation of GRB 230911D (long)
  100. GRB 230911D: Fermi-LAT detection

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