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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"

36380 results found.

  1. GRB 230321A: CALET Gamma-Ray Burst Monitor detection
  2. GRB 230320B: CALET Gamma-Ray Burst Monitor detection
  3. GRB 230320B: Swift/BAT-GUANO detection outside the coded FOV
  4. Fermi GRB 230320A: Global MASTER-Net observations report
  5. Fermi GRB 230321A: Global MASTER-Net observations report
  6. GRB 230321B: AstroSat CZTI detection
  7. GRB 230320B: AstroSat CZTI detection
  8. GRB 230321A: BALROG localization (Fermi Trigger 701065308 / GRB 230321182)
  9. GRB 230321A: Fermi GBM Final Real-time Localization
  10. GRB 230320A: Fermi GBM Final Real-time Localization
  11. GRB 230314A: TURBO Optical Upper Limit
  12. GRB 230307A: Continued Gemini-South observations confirm rapid optical fading
  13. IPN triangulation of GRB 230309A
  14. Fermi GRB 230316A: Global MASTER-Net observations report
  15. GRB 230304D: AstroSat CZTI detection
  16. GRB 230316A: Fermi GBM Final Real-time Localization
  17. IPN triangulation of GRB 230304B
  18. GRB 230313A: AstroSat CZTI detection
  19. GRB 230307A: Far off-axis NuSTAR detection of the GRB
  20. IPN triangulation of GRB 230308A (short/bright)
  21. Fermi GRB 230314A: Global MASTER-Net observations report
  22. GRB 230307A: ATCA radio detection
  23. GRB 230314A: Fermi GBM Final Real-time Localization
  24. VZLUSAT-2 detection of SGR 1806-20
  25. GRB 230307A: INTEGRAL upper limit on Hard X-ray afterglow
  26. GRB 230307A: Swift/UVOT detection
  27. GRB 230313A: BALROG localization (Fermi Trigger 700400328 / GRB 230313485)
  28. Fermi GRB 230313A: Global MASTER-Net observations report
  29. GRB 230313A: Fermi GBM Final Real-time Localization
  30. GRB 230307A: soft X-ray detection with LEIA
  31. GRB 230307A: Swift-XRT afterglow detection
  32. GRB 230309A: AstroSat CZTI detection of a bright long GRB
  33. Further improved IPN localization for GRB 230307A
  34. GRB 230307A: SOAR/Goodman detection of the possible host galaxy
  35. GRB 230308A: CALET Gamma-Ray Burst Monitor detection
  36. GRB 230310A: AstroSat CZTI detection
  37. GRB 230307A: GECKO optical observations and detections of the afterglow
  38. GRB 230307A: MAXI/GSC upper limit
  39. GRB 230307A: Gemini-South Confirmation of the Optical Afterglow
  40. Fermi GRB 230310A: Global MASTER-Net observations report
  41. GRB 230310A: Fermi GBM Final Real-time Localization
  42. GRB 230307A: AGILE/MCAL analysis
  43. GRB 230307A: ATLAS information on the ULTRACAM optical afterglow candidate
  44. GRB 230307A: Erratum of the GCN 33441
  45. GRB 230204B: MASTER detection of an object near NTT Optical Afterglow Candidate
  46. GRB 230308A: Fermi GBM detection
  47. GRB 230307A: Possible optical afterglow
  48. GRB 230307A: ASO-S/HXI detection
  49. GRB 230307A: AstroSat LAXPC detection
  50. GRB 230228A: NUTTelA-TAO / BSTI Optical Limits
  51. GRB 230308A: AGILE/MCAL detection
  52. GRB 230307A: optical upper limit
  53. GRB 230217A: ATCA rapid-response radio detection
  54. Swift Trigger 1159108 is not a GRB
  55. GRB 230307A: Swift/BAT upper limits on the early afterglow
  56. GRB 230307A: Upper limits from a neutrino search with IceCube
  57. GRB 230307A: Swift-XRT observations
  58. Fermi GRB 230307A: Global MASTER-Net observations report
  59. Konus-Wind detection of GRB 230307A
  60. GRB 230228A: VIRT Optical Upper Limit
  61. Improved IPN localization for GRB 230307A
  62. GRB 230307A: VZLUSAT-2 detection
  63. GRB 230304B: CALET Gamma-Ray Burst Monitor detection
  64. Fermi GRB 230308A: Global MASTER-Net observations report
  65. GRB 230308A: BALROG localization (Fermi Trigger 699975152 / GRB 230308564)
  66. GRB 230308A: Fermi GBM Final Real-time Localization
  67. GRB 230307A: Tiled Swift observations
  68. GRB 230307A: Detection by GRBAlpha
  69. GRB 230305A: Detection by GRBAlpha
  70. GRB 230307A: BALROG localization (Fermi Trigger 699896651/ GRB 230307656)
  71. GRB 230307A: AstroSat CZTI detection
  72. GRB 230307A: possibly the second highest GRB energy fluence ever identified
  73. IPN triangulation of GRB 230307A (long/very bright)
  74. GRB 230307A: AGILE/MCAL detection
  75. GRB 230307A: Fermi GBM Observation of a very bright burst
  76. Solar Orbiter STIX observation of GRB 230307A
  77. GRB 230307A: Fermi GBM detection of a very bright GRB
  78. GRB 230307A: GECAM detection of an extremely bright burst
  79. GRB 230307A: Fermi GBM Final Real-time Localization
  80. GRB 230304C: AstroSat CZTI detection
  81. GRB 230304B: AstroSat CZTI detection
  82. GRB 230304A: AstroSat CZTI detection
  83. GRB 230304B: Detection by GRBAlpha
  84. GRB 230304C: Fermi GBM Final Real-time Localization
  85. GRB 230304B: Fermi GBM Final Real-time Localization
  86. GRB 230304A: Fermi GBM Final Real-time Localization
  87. GRB 230228A: 6 GHz VLA radio upper limit
  88. GRB 230228A: Swift-BAT refined analysis
  89. GRB 230228A: Swift/UVOT Upper Limits
  90. Fermi GRB 230301B: Global MASTER-Net observations report
  91. GRB 230301B: Fermi GBM Final Real-time Localization
  92. GRB 230228A: Fermi GBM Observation
  93. GRB 230228A: OSN optical upper limit
  94. GRB 230301A: Fermi GBM Final Real-time Localization
  95. GRB 230228A: Swift-XRT refined Analysis
  96. GRB 230228A: Mondy optical upper limit
  97. GRB 230228A: Enhanced Swift-XRT position
  98. GRB 230228A: Nanshan/NEXT optical upper limit
  99. GRB 230228A: Miryang Arirang Astronomical Observatory (MAAO) 0.7-m telescope optical upper limit
  100. GRB 230228A: Prompt enhanced Swift-XRT position

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