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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

38349 results found.

  1. GRB 240123A: Mondy continued optical observations and the PL decay index
  2. GRB 240123A: SAO RAS optical observations
  3. GRB 240123A : MITSuME Akeno optical afterglow candidate detection
  4. Fermi/GBM trigger 727752941: BALROG analysis retraction
  5. GRB 240123A: Enhanced Swift-XRT position
  6. GRB 240124A?: BALROG localization (Fermi Trigger 727752941 / GRB 240124066)
  7. Fermi GRB 240123B: Global MASTER-Net observations report
  8. GRB 240122A: Swift/UVOT Upper Limits
  9. GRB 240123A: Swift-XRT refined Analysis
  10. GRB 240122A: BOOTES-2/TELMA optical upper limit and 1.5m OSN detection
  11. Fermi GBM Sub-Threshold Detection of GRB 240123A
  12. GRB 240123A: Mondy continued optical observations + correction of the GRB name in GCN 35605
  13. GRB 240123B: Fermi GBM Final Real-time Localization
  14. GRB 240118A: Swift/UVOT Upper Limits
  15. GRB 240122B: Glowbug gamma-ray detection
  16. GRB 240123A: Mondy optical afterglow observations
  17. Konus-Wind detection of GRB 240112A
  18. GRB 240123A: Swift detection of a burst with a possible optical counterpart
  19. Swift GRB240123.46: Global MASTER-Net observations report
  20. GRB 240122A: Swift-XRT afterglow detection
  21. GRB 240122A: VLT/X-shooter redshift confirmation
  22. GRB 240122A: Redshift from OSIRIS+/GTC
  23. GRB 240122A: LT non-detection of GOTO candidate counterpart confirms fading
  24. GRB 240122A: GOTO optical counterpart candidate
  25. GRB 240122A: Tiled Swift observations
  26. Konus-Wind detection of GRB 240119A (short/hard)
  27. GRB 240122A: MAXI/GSC detection
  28. IPN triangulation of GRB 240119A (short)
  29. GRB 240119A: GECAM detection of a short burst
  30. GRB 240118C: GECAM-B detection of a long burst
  31. GRB 240119A: AstroSat CZTI detection of a short burst
  32. GRB 240118A: Mondy optical observations
  33. GRB 240118A: Swift-XRT afterglow detection
  34. GRB 240118C: Fermi GBM Observation
  35. Fermi GRB 240119A: Global MASTER-Net observations report
  36. IceCube-240105A: Detection of NIR flare of PKS 0446+11 with WINTER
  37. GRB 240119A: Fermi GBM Final Localization
  38. GRB 240117A: CALET Gamma-Ray Burst Monitor detection
  39. GRB 240118C: Swift/BAT-GUANO detection of a burst
  40. GRB 240118A: GRBAlpha detection
  41. GRB 240115A: Fermi GBM Observation
  42. GRB 240118C: Fermi GBM Final Localization
  43. GRB 240118D: AstroSat CZTI detection
  44. GRB 240117A: AstroSat CZTI detection
  45. GRB 240118A: Swift ToO observations
  46. GRB 240118A: AbAO optical upper limit
  47. Fermi GRB 240118B: Global MASTER-Net observations report
  48. GRB 240118A: NuSTAR Offline Analysis of the GRB
  49. GRB 240117A: Glowbug gamma-ray detection
  50. GRB 240118A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  51. Konus-Wind detection of GRB 240118A
  52. GRB 240118C: BALROG localization (Fermi Trigger 727291408 / GRB 240118725)
  53. GRB 240118A: NuSTAR Detection of a Long GRB
  54. GRB 240118A: Fermi GBM Observation
  55. GRB 240118B: Fermi GBM Final Real-time Localization
  56. LAT GRB240118.08: Global MASTER-Net observations report
  57. GRB 240118A: Fermi-LAT detection
  58. GRID detection of GRB 231230A
  59. GRB 240118A: Fermi GBM Final Real-time Localization
  60. GRB 240115A: Swift/BAT-GUANO detection of a short burst
  61. IPN triangulation of GRB 240112A (long)
  62. GRB 240115B: AstroSat CZTI detection
  63. LIGO/Virgo/KAGRA S240109a: Upper limits from Swift/BAT-GUANO
  64. GRB 240115B: Fermi GBM Detection
  65. GRB 240112D: Glowbug gamma-ray detection
  66. GRB 240112C: Glowbug gamma-ray detection
  67. GRB 240112C: VZLUSAT-2 detection
  68. GRB 240107A: VZLUSAT-2 detection
  69. Integral GRB240115.70: Global MASTER-Net observations report
  70. Fermi GRB 240115B: Global MASTER-Net observations report
  71. GRB 240115B: A long GRB detected by INTEGRAL
  72. GRB 240115B: Fermi GBM Final Real-time Localization
  73. Konus-Wind detection of GRB 240112C
  74. Fermi GRB 240115A: Global MASTER-Net observations report
  75. GRB 240115A: Fermi GBM Final Real-time Localization
  76. GRB 240112C: GRBAlpha detection
  77. GRB 240114A: MAXI/GSC detection
  78. GRB 240112C: Swift/UVOT Detection
  79. GRB 240112C: Fermi GBM Detection
  80. Fermi trigger No 726773850: Global MASTER-Net observations report
  81. GRB 240112C: Swift-XRT refined Analysis
  82. GRB 240112C: SAO RAS optical observations
  83. GRB 240112E: Fermi GBM Final Localization
  84. Fermi GRB 240112D: Global MASTER-Net observations report
  85. GRB 240112D: Fermi GBM Final Real-time Localization
  86. Fermi trigger No 726774492: Global MASTER-Net observations report
  87. Swift GRB 240112C: Global MASTER-Net observations report
  88. Fermi GRB 240112B: Global MASTER-Net observations report
  89. GRB 240109A: Swift-BAT refined analysis
  90. GRB 240112C: Swift detection of a burst with an optical counterpart
  91. GRB 240112B: Fermi GBM Final Real-time Localization
  92. GRB 240112A: GECAM detection of a burst
  93. GRB 240109A: Fermi GBM Observation
  94. GRB 240110A: AstroSat CZTI detection
  95. Fermi-LAT detection of increased gamma-ray activity of blazar PKS 0446+11, located inside the IceCube-240105A error region
  96. GRB 240108A: Glowbug gamma-ray detection
  97. GRB 231214A: ATCA Radio Upper Limits
  98. GRB 240106B: Glowbug gamma-ray detection
  99. GRB 240106A: Glowbug gamma-ray detection
  100. GRB 240109B: Fermi GBM Final Real-time Localization

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