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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"

21986 results found.

  1. GRB 230818A: radio observation with the VLA
  2. GRB 230205A: LBT spectroscopy of two host galaxy candidates
  3. GRB 230906A: Swift-XRT observations
  4. GRB 230906A: Swift ToO observations
  5. Fermi GRB 230906A: Global MASTER-Net observations report
  6. GRB 230903A: VLT/X-shooter optical observations
  7. Fermi trigger No 715552087: Global MASTER-Net observations report
  8. Fermi trigger No 715429986: Global MASTER-Net observations report
  9. Fermi GRB 230903A: Global MASTER-Net observations report
  10. Fermi GRB 230904A: Global MASTER-Net observations report
  11. Swift GRB230903.72: Global MASTER-Net observations report
  12. Integral GRB230902.00: Global MASTER-Net observations report
  13. GRB 230827B: Swift-XRT afterglow detection
  14. GRB 230827B: Swift ToO observations
  15. GRB 230827A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  16. Subject: GRB230826A: Swift/UVOT upper limits
  17. Fermi trigger No 714809315: Global MASTER-Net observations report
  18. GRB 230827.256: AKO Optical follow-up of ZTF23abaanxz (AT 2023qxj)
  19. Fermi GRB 230827A: Global MASTER-Net observations report
  20. Swift J1727.8-1613 (GRB 230824A): Osservatorio Astronomico "Nastro Verde" optical observations
  21. GRB 230827.256 : GIT optical follow-up of ZTF23abaanxz/AT2023qxj
  22. Swift J1727.8-1613 (GRB 230824A): Montarrenti Observatory photometric observations
  23. Swift J1727.8-1613 (GRB 230824A): Leavitt Observatory optical observations
  24. GRB 230826A: Mondy optical observations
  25. Swift J1727.8-1613 (GRB 230824A): GAD Observatory La Spezia - optical observations
  26. Swift GRB230826.81: Global MASTER-Net observations report
  27. Swift J1727.8-1613 (GRB 230824A): Bassano Bresciano Observatory optical observations
  28. GRB 230824A: AKO Photometric Follow-up Observations
  29. LIGO/Virgo/KAGRA S230825k: Upper limits from Swift/BAT-GUANO
  30. Swift GRB230825.85: Global MASTER-Net observations report
  31. Trigger 1187225: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  32. Swift J1727.8-1613 (GRB 230824A): Skynet Optical Observations
  33. Trigger 1187207: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  34. Trigger 1187203: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  35. Swift GRB230825.75: Global MASTER-Net observations report
  36. GRB 230812B: radio detection with the VLA
  37. NICER detection of Swift J1727.8-1613 (GRB 230824A)
  38. Fermi trigger No 714618399: Global MASTER-Net observations report
  39. MAXI/GSC detection of Swift J1727.8-1613 (GRB 230824A)
  40. GRB 230824A: AKO Optical Afterglow Candidate
  41. GRB 230824A is likely a Galactic Transient: Swift J1727.8-1613
  42. Integral GRB230824.72: Global MASTER-Net observations report
  43. Swift GRB230824.58: Global MASTER-Net observations report
  44. Swift GRB230824.10: Global MASTER-Net observations report
  45. LIGO/Virgo/KAGRA S230822bm: Upper limits from Swift/BAT-GUANO
  46. GRB 230822A: Swift/BAT-GUANO detection of a burst
  47. IceCube-230823A: Event likely due to background
  48. GRB 230812B: Assy optical observations, possible SN rise
  49. GRB 230815A: ATCA detection of radio counterpart
  50. Swift GRB230821.64: Global MASTER-Net observations report
  51. GRB 230812B: SAO RAS RC-500 and Zeiss-1000 observations
  52. GRB 20230818A: GIT optical upper limit
  53. GRB 230812B : GRANDMA/Kilonova-Catcher optical afterglow detection and upper limits
  54. Swift GRB230820.81: Global MASTER-Net observations report
  55. Swift GRB230820.80: Global MASTER-Net observations report
  56. Swift GRB230820.82: Global MASTER-Net observations report
  57. GRB 230818A: Nickel and KAIT telescope optical observations
  58. GRB 230818A: SAO RAS 6-m telescope spectroscopy
  59. GRB 230812B: SAO RAS Zeiss-1000 observations
  60. GRB 230818A: further SAO RAS Zeiss-1000 observations
  61. GRB 230818A: Tautenburg observations
  62. GRB 230818A: Leavitt Observatory upper limit
  63. GRB 230818A: Bassano Bresciano Observatory optical observations
  64. GRB 230818A: KGO RC-25 optical observations
  65. GRB 230818A: Swift/UVOT Detection
  66. GRB 230818A: NOT photometry and spectroscopy
  67. GRB 230818A: SAO RAS Zeiss-1000 observations
  68. Fermi GRB 230818A: Global MASTER-Net observations report
  69. Fermi trigger No 713974668: Global MASTER-Net observations report
  70. GRB 230818A: GOTO optical afterglow detection
  71. Swift GRB230818.98: Global MASTER-Net observations report
  72. GRB 230812B: SAO RAS observations, possible re-brightening
  73. GRB 230812B: SAO RAS optical observations
  74. GRB 230816A: Osservatorio Astronomico "Nastro Verde" optical observations
  75. GRB 230812B: NOEMA detection
  76. GRB 230815A: VLT/HAWK-I near-infrared afterglow detection
  77. Fermi GRB 230817A: Global MASTER-Net observations report
  78. GRB 230812B: SAO RAS optical observations
  79. GRB230816A: Possible host and GIT detection of optical counterpart
  80. GRB 230816A: Tautenburg observations
  81. GRB 230816A: AKO Optical Observations
  82. GRB 230816A: TShAO and Assy optical observations
  83. GRB 230816A: SAO RAS optical observations
  84. Swift GRB230816.80: Global MASTER-Net observations report
  85. GRB 230816A: Nanshan/HMT optical afterglow detection
  86. GRB 230815A: SOAR/Goodman follow-up imaging
  87. Swift GRB230816.67: Global MASTER-Net observations report
  88. GRB230815A: Swift/UVOT upper limits
  89. GRB 230812B: GAD Observatory optical observations (upper limit)
  90. Swift GRB 230815A: Global MASTER-Net observations report
  91. Fermi GRB 230814A: Global MASTER-Net observations report
  92. GRB 230812B: Iota Scorpii Observatory, La Spezia, Italy
  93. GRB 230812B: Tautenburg observations
  94. GRB 230812B: AMI-LA radio detection of afterglow candidate
  95. GRB 230812B: continued AbAO optical afterglow observations
  96. GRB 230812B: Optical observaions from Rozhen Observatory
  97. GRB 230812B: Further Bassano Bresciano Observatory optical observations
  98. GRB 230812B: further SAO RAS optical observations
  99. GRB 230812B: GRANDMA further observations of ZTF23aaxeacr candidate afterglow
  100. GRB 230812B: CrAO ZTSh optical observations

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