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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"

37767 results found.

  1. GRB 230905A: Fermi GBM Final Real-time Localization
  2. GRB 230903A: Swift-XRT refined Analysis
  3. GRB 230903A: Enhanced Swift-XRT position
  4. GRB 230903A: VLT/X-shooter optical observations
  5. GRB 230903A: Swift-BAT refined analysis
  6. GRB 230904C: Fermi GBM Final Localization
  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. GRB 230903A: Fermi GBM detection
  11. GRB 230904B is not a GRB
  12. GRB 230904B: BALROG localization (Fermi Trigger 715526984 / GRB 230904562)
  13. Fermi GRB 230904A: Global MASTER-Net observations report
  14. GRB 230904A: Fermi GBM Final Real-time Localization
  15. GRB 230903A: LCOGT Optical Upper Limits
  16. GRB 230903A: Swift detection of a burst
  17. GRB 230903A: Fermi GBM Final Real-time Localization
  18. GRB 230827B: Glowbug gamma-ray detection
  19. GRB 230827A: Glowbug gamma-ray detection
  20. GRB 230826A: Glowbug gamma-ray detection
  21. GRB 230827B: Swift-XRT afterglow detection
  22. GRB 230812B: Spectroscopic detection of the associated SN 2023pel.
  23. GRB 230827B: Swift ToO observations
  24. GRB 230827A: Fermi GBM Observation
  25. GRB 230827B: CALET Gamma-Ray Burst Monitor detection
  26. GRB 230826A: Swift-BAT refined analysis
  27. GRB 230828A: AstroSat CZTI detection
  28. GRB 230828A: GRBAlpha detection
  29. Swift Trigger 1188089 is not a GRB
  30. GRB 230827A: VZLUSAT-2 detection
  31. GRB 230827A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  32. GRB 230826A: VZLUSAT-2 detection
  33. GRB 230827B: VZLUSAT-2 detection
  34. GRB 230827B / GRB 230827256: Fermi GBM Observation
  35. GRB 230827A: GRBAlpha detection
  36. Subject: GRB230826A: Swift/UVOT upper limits
  37. GRB 230827A: BALROG localization (Fermi Trigger / GRB 230827762)
  38. Fermi trigger No 714809315: Global MASTER-Net observations report
  39. GRB 230827.256: AKO Optical follow-up of ZTF23abaanxz (AT 2023qxj)
  40. Fermi GRB 230827A: Global MASTER-Net observations report
  41. Swift J1727.8-1613 (GRB 230824A): Osservatorio Astronomico "Nastro Verde" optical observations
  42. GRB 230827.256 : GIT optical follow-up of ZTF23abaanxz/AT2023qxj
  43. GRB 230827A: Fermi GBM Final Real-time Localization
  44. AT 2023qxj: ZTF discovery of the likely afterglow of Fermi GRB 230827256
  45. Swift J1727.8-1613 (GRB 230824A): Montarrenti Observatory photometric observations
  46. GRB 230826A: GRBAlpha detection
  47. GRB 230826A: Fermi GBM Observation
  48. Swift J1727.8-1613 (GRB 230824A): Leavitt Observatory optical observations
  49. GRB 230826A: Enhanced Swift-XRT position
  50. GRB 230826A: Swift-XRT refined Analysis
  51. GRB 230826A: Mondy optical observations
  52. Swift J1727.8-1613 (GRB 230824A): GAD Observatory La Spezia - optical observations
  53. GRB 230826A: Swift detection of a burst
  54. GRB 230826A: Fermi GBM Final Real-time Localization
  55. Swift J1727.8-1613 (GRB 230824A): Bassano Bresciano Observatory optical observations
  56. GRB 230824A: AKO Photometric Follow-up Observations
  57. GRB 230818B: CALET Gamma-Ray Burst Monitor detection
  58. LIGO/Virgo/KAGRA S230825k: Upper limits from Swift/BAT-GUANO
  59. Trigger 1187225: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  60. Swift J1727.8-1613 (GRB 230824A): Skynet Optical Observations
  61. Trigger 1187207: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  62. Trigger 1187203: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  63. GRB 230812B: radio detection with the VLA
  64. Fermi Gamma-ray Burst Monitor trigger 714618399/230825046 is not a GRB
  65. NICER detection of Swift J1727.8-1613 (GRB 230824A)
  66. Trigger 1187142: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  67. Fermi trigger No 714618399: Global MASTER-Net observations report
  68. MAXI/GSC detection of Swift J1727.8-1613 (GRB 230824A)
  69. GRB 230824A: AKO Optical Afterglow Candidate
  70. Trigger 1186982: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)
  71. IBAS trigger 10375 is not a GRB
  72. GRB 230824A is likely a Galactic Transient: Swift J1727.8-1613
  73. GRB 230824B: AstroSat CZTI detection
  74. GRB 230824A: Swift detection of a burst
  75. Swift Trigger 1186908 is not a GRB
  76. GRB 230822A: Fermi GBM Observation
  77. LIGO/Virgo/KAGRA S230822bm: Upper limits from Swift/BAT-GUANO
  78. GRB 230822A: Swift/BAT-GUANO detection of a burst
  79. IceCube-230823A - IceCube observation of a high-energy neutrino candidate track-like event
  80. GRB 230812B: AstroSat LAXPC detection
  81. GRB 230818B: VZLUSAT-2 detection
  82. GRB 230818B: AstroSat CZTI detection
  83. GRID detection of GRB 230818A
  84. GRB 230822A: Fermi GBM Final Real-time Localization
  85. GRB 230812B: Assy optical observations, possible SN rise
  86. GRB 230815A: ATCA detection of radio counterpart
  87. GRB 230812B: SAO RAS RC-500 and Zeiss-1000 observations
  88. GRB 230818A: Swift-BAT refined analysis
  89. GRB 20230818A: GIT optical upper limit
  90. Swift Trigger 1186391 is not a GRB
  91. Swift Trigger 1186390 is not a GRB
  92. Konus-Wind detection of GRB 230818A
  93. Swift Trigger 1186386 is not a GRB
  94. GRB 230812B : GRANDMA/Kilonova-Catcher optical afterglow detection and upper limits
  95. GRB 230820A: AstroSat CZTI detection
  96. GRB 230818A: Fermi GBM Observation
  97. GRB 230812B: GIT Confirmation of SN rise
  98. GRB 230818A: Nickel and KAIT telescope optical observations
  99. GRB 230818A: SAO RAS 6-m telescope spectroscopy
  100. GRB 230812B: SAO RAS Zeiss-1000 observations

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