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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"

36405 results found.

  1. GRB 230904A: Fermi GBM Final Real-time Localization
  2. GRB 230903A: LCOGT Optical Upper Limits
  3. GRB 230903A: Swift detection of a burst
  4. GRB 230903A: Fermi GBM Final Real-time Localization
  5. GRB 230827B: Glowbug gamma-ray detection
  6. GRB 230827A: Glowbug gamma-ray detection
  7. GRB 230826A: Glowbug gamma-ray detection
  8. GRB 230827B: Swift-XRT afterglow detection
  9. GRB 230812B: Spectroscopic detection of the associated SN 2023pel.
  10. GRB 230827B: Swift ToO observations
  11. GRB 230827A: Fermi GBM Observation
  12. GRB 230827B: CALET Gamma-Ray Burst Monitor detection
  13. GRB 230826A: Swift-BAT refined analysis
  14. GRB 230828A: AstroSat CZTI detection
  15. GRB 230828A: GRBAlpha detection
  16. Swift Trigger 1188089 is not a GRB
  17. GRB 230827A: VZLUSAT-2 detection
  18. GRB 230827A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  19. GRB 230826A: VZLUSAT-2 detection
  20. GRB 230827B: VZLUSAT-2 detection
  21. GRB 230827B / GRB 230827256: Fermi GBM Observation
  22. GRB 230827A: GRBAlpha detection
  23. Subject: GRB230826A: Swift/UVOT upper limits
  24. GRB 230827A: BALROG localization (Fermi Trigger / GRB 230827762)
  25. GRB 230827.256: AKO Optical follow-up of ZTF23abaanxz (AT 2023qxj)
  26. Fermi GRB 230827A: Global MASTER-Net observations report
  27. Swift J1727.8-1613 (GRB 230824A): Osservatorio Astronomico "Nastro Verde" optical observations
  28. GRB 230827.256 : GIT optical follow-up of ZTF23abaanxz/AT2023qxj
  29. GRB 230827A: Fermi GBM Final Real-time Localization
  30. AT 2023qxj: ZTF discovery of the likely afterglow of Fermi GRB 230827256
  31. Swift J1727.8-1613 (GRB 230824A): Montarrenti Observatory photometric observations
  32. GRB 230826A: GRBAlpha detection
  33. GRB 230826A: Fermi GBM Observation
  34. Swift J1727.8-1613 (GRB 230824A): Leavitt Observatory optical observations
  35. GRB 230826A: Enhanced Swift-XRT position
  36. GRB 230826A: Swift-XRT refined Analysis
  37. GRB 230826A: Mondy optical observations
  38. Swift J1727.8-1613 (GRB 230824A): GAD Observatory La Spezia - optical observations
  39. GRB 230826A: Swift detection of a burst
  40. GRB 230826A: Fermi GBM Final Real-time Localization
  41. Swift J1727.8-1613 (GRB 230824A): Bassano Bresciano Observatory optical observations
  42. GRB 230824A: AKO Photometric Follow-up Observations
  43. GRB 230818B: CALET Gamma-Ray Burst Monitor detection
  44. LIGO/Virgo/KAGRA S230825k: Upper limits from Swift/BAT-GUANO
  45. Trigger 1187225: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  46. Swift J1727.8-1613 (GRB 230824A): Skynet Optical Observations
  47. Trigger 1187207: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  48. Trigger 1187203: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  49. GRB 230812B: radio detection with the VLA
  50. Fermi Gamma-ray Burst Monitor trigger 714618399/230825046 is not a GRB
  51. NICER detection of Swift J1727.8-1613 (GRB 230824A)
  52. Trigger 1187142: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  53. MAXI/GSC detection of Swift J1727.8-1613 (GRB 230824A)
  54. GRB 230824A: AKO Optical Afterglow Candidate
  55. Trigger 1186982: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  56. IBAS trigger 10375 is not a GRB
  57. GRB 230824A is likely a Galactic Transient: Swift J1727.8-1613
  58. GRB 230824B: AstroSat CZTI detection
  59. GRB 230824A: Swift detection of a burst
  60. Swift Trigger 1186908 is not a GRB
  61. GRB 230822A: Fermi GBM Observation
  62. LIGO/Virgo/KAGRA S230822bm: Upper limits from Swift/BAT-GUANO
  63. GRB 230822A: Swift/BAT-GUANO detection of a burst
  64. IceCube-230823A: Event likely due to background
  65. GRB 230812B: AstroSat LAXPC detection
  66. GRB 230818B: VZLUSAT-2 detection
  67. GRB 230818B: AstroSat CZTI detection
  68. GRID detection of GRB 230818A
  69. GRB 230822A: Fermi GBM Final Real-time Localization
  70. GRB 230812B: Assy optical observations, possible SN rise
  71. GRB 230815A: ATCA detection of radio counterpart
  72. GRB 230812B: SAO RAS RC-500 and Zeiss-1000 observations
  73. GRB 230818A: Swift-BAT refined analysis
  74. GRB 20230818A: GIT optical upper limit
  75. Swift Trigger 1186391 is not a GRB
  76. Swift Trigger 1186390 is not a GRB
  77. Konus-Wind detection of GRB 230818A
  78. Swift Trigger 1186386 is not a GRB
  79. GRB 230812B : GRANDMA/Kilonova-Catcher optical afterglow detection and upper limits
  80. GRB 230820A: AstroSat CZTI detection
  81. GRB 230818A: Fermi GBM Observation
  82. GRB 230812B: GIT Confirmation of SN rise
  83. GRB 230818A: Nickel and KAIT telescope optical observations
  84. GRB 230818A: SAO RAS 6-m telescope spectroscopy
  85. GRB 230812B: SAO RAS Zeiss-1000 observations
  86. GRB 230818A: further SAO RAS Zeiss-1000 observations
  87. GRB 230818A: AKO Upper Limit
  88. GRB 230818A: AstroSat CZTI detection
  89. GRB 230818A: Tautenburg observations
  90. GRB 230818A: Leavitt Observatory upper limit
  91. GRB 230818A: Swift-XRT refined Analysis
  92. GRB 230818A: Bassano Bresciano Observatory optical observations
  93. GRB 230818A: KGO RC-25 optical observations
  94. GRB 230818A: Swift/UVOT Detection
  95. GRB 230818A: NOT photometry and spectroscopy
  96. GRB 230818A: Enhanced Swift-XRT position
  97. GRB 230818A: SAO RAS Zeiss-1000 observations
  98. Fermi GRB 230818A: Global MASTER-Net observations report
  99. GRB 230818A: GOTO optical afterglow detection
  100. GRB 230818A: Swift detection of a burst

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