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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"

32571 results found.

  1. GRB 230328B: Mondy, AbAO and Kitab optical observations
  2. GRB 230328B: Mondy optical afterglow confirmation
  3. Fermi GRB 230328A: Global MASTER-Net observations report
  4. GRB 230325A: Swift-BAT refined analysis
  5. GRB 230325A: Swift/UVOT Upper Limits
  6. GRB 230325A: X-shooter optical afterglow and redshift
  7. GRB 230325A: Swift-XRT refined Analysis
  8. GRB 230322B: Swift-BAT refined analysis
  9. GRB 230320B: Fermi GBM Observation
  10. GRB 230322B: Swift/UVOT Detection
  11. Konus-Wind detection of GRB 230309A
  12. Konus-Wind detection of GRB 230308A
  13. Konus-Wind detection of GRB 230304B
  14. GRB 230322B: Swift-XRT refined Analysis
  15. Swift GRB 230322B: Global MASTER-Net observations report
  16. GRB 230320B: GRBAlpha detection
  17. GRB 230321A: CALET Gamma-Ray Burst Monitor detection
  18. GRB 230320B: CALET Gamma-Ray Burst Monitor detection
  19. GRB 230320B: Swift/BAT-GUANO detection outside the coded FOV
  20. Fermi GRB 230320A: Global MASTER-Net observations report
  21. Fermi GRB 230321A: Global MASTER-Net observations report
  22. SGR 1806-20: Correction to GCN 33494
  23. GRB 230314A: TURBO Optical Upper Limit
  24. GRB 230307A: Continued Gemini-South observations confirm rapid optical fading
  25. IPN triangulation of GRB 230309A
  26. Fermi GRB 230316A: Global MASTER-Net observations report
  27. IPN triangulation of GRB 230304B
  28. GRB 230313A: AstroSat CZTI detection
  29. GRB 230307A: Far off-axis NuSTAR detection of the GRB
  30. IPN triangulation of GRB 230308A (short/bright)
  31. Fermi GRB 230314A: Global MASTER-Net observations report
  32. GRB 230307A: ATCA radio detection
  33. VZLUSAT-2 detection of SGR 1806-20
  34. GRB 230307A: INTEGRAL upper limit on Hard X-ray afterglow
  35. GRB 230307A: Swift/UVOT detection
  36. Fermi GRB 230313A: Global MASTER-Net observations report
  37. GRB 230307A: soft X-ray detection with LEIA
  38. GRB 230307A: Swift-XRT afterglow detection
  39. Further improved IPN localization for GRB 230307A
  40. GRB 230307A: SOAR/Goodman detection of the possible host galaxy
  41. TESS Detection of the Optical Afterglow of GRB230307A
  42. GRB 230308A: CALET Gamma-Ray Burst Monitor detection
  43. GRB 230310A: AstroSat CZTI detection
  44. GRB 230307A: GECKO optical observations and detections of the afterglow
  45. GRB 230307A: MAXI/GSC upper limit
  46. GRB 230307A: Gemini-South Confirmation of the Optical Afterglow
  47. Fermi GRB 230310A: Global MASTER-Net observations report
  48. GRB 230307A: ATLAS information on the ULTRACAM optical afterglow candidate
  49. GRB 230307A: Erratum of the GCN 33441
  50. GRB 230204B: MASTER detection of an object near NTT Optical Afterglow Candidate
  51. GRB 230308A: Fermi GBM detection
  52. GRB 230307A: Possible optical afterglow
  53. GRB 230228A: NUTTelA-TAO / BSTI Optical Limits
  54. GRB 230308A: AGILE/MCAL detection
  55. GRB 230217A: ATCA rapid-response radio detection
  56. GRB 230307A: Swift/BAT upper limits on the early afterglow
  57. GRB 230307A: Upper limits from a neutrino search with IceCube
  58. GRB 230307A: Swift-XRT observations
  59. Fermi GRB 230307A: Global MASTER-Net observations report
  60. Konus-Wind detection of GRB 230307A
  61. GRB 230228A: VIRT Optical Upper Limit
  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 230307A: Tiled Swift observations
  66. GRB 230307A: Detection by GRBAlpha
  67. GRB 230307A: BALROG localization (Fermi Trigger 699896651/ GRB 230307656)
  68. GRB 230307A: AstroSat CZTI detection
  69. GRB 230307A: possibly the second highest GRB energy fluence ever identified
  70. IPN triangulation of GRB 230307A (long/very bright)
  71. GRB 230307A: AGILE/MCAL detection
  72. GRB 230307A: Fermi GBM Observation of a very bright burst
  73. Fermi-LAT gamma-ray observations of IceCube-230306A
  74. GRB 230307A: Fermi GBM detection of a very bright GRB
  75. GRB 230307A: GECAM detection of an extremely bright burst
  76. GRB 230304C: AstroSat CZTI detection
  77. GRB 230304B: AstroSat CZTI detection
  78. GRB 230304A: AstroSat CZTI detection
  79. GRB 230304B: Detection by GRBAlpha
  80. GRB 230228A: 6 GHz VLA radio upper limit
  81. GRB 230228A: Swift-BAT refined analysis
  82. GRB 230228A: Swift/UVOT Upper Limits
  83. Fermi GRB 230301B: Global MASTER-Net observations report
  84. GRB 230228A: Fermi GBM Observation
  85. GRB 230228A: OSN optical upper limit
  86. GRB 230228A: Swift-XRT refined Analysis
  87. GRB 230228A: Mondy optical upper limit
  88. GRB 230228A: Nanshan/NEXT optical upper limit
  89. GRB 230228A: Miryang Arirang Astronomical Observatory (MAAO) 0.7-m telescope optical upper limit
  90. Fermi GRB 230227A: Global MASTER-Net observations report
  91. GRB 230217A: VLT/FORS2 optical observations and candidate counterpart
  92. GRB 230216A Mondy Observations
  93. GRB 230205A: VLA radio afterglow confirmation
  94. GRB 230217A: Swift/UVOT Upper Limits
  95. GRB 230216A: Swift/UVOT Upper Limits
  96. GRB 230217A: Continued Gemini Observations
  97. GRB 230220A: Correction to GCN 33352
  98. GRB 230217A: Swift-XRT afterglow detection
  99. Fermi-LAT gamma-ray observations of IceCube-230220A
  100. GRB 230217A: Swift-BAT refined analysis

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