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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"

36215 results found.

  1. GRB 230808A: Swift/BAT-GUANO detection of a burst
  2. GRB 230808B: Fermi GBM Final Real-time Localization
  3. ZTF23aaoohpy/AT2023lcr: JWST observations consistent with the presence of a supernova
  4. GRB 230808A: Fermi GBM Final Real-time Localization
  5. GRB 230805B : MITSuME Akeno optical upper limits
  6. Fermi GRB 230807A: Global MASTER-Net observations report
  7. GRB 230807A: Fermi GBM Final Real-time Localization
  8. LIGO/Virgo/KAGRA S230805x: Upper limits from Swift/BAT-GUANO
  9. Konus-Wind detection of GRB 230803A
  10. GRB 230805B: Fermi GBM observation
  11. GRB 230805B : OHP/T193 optical upper limit
  12. GRB 230806A: Fermi GBM Final Localization
  13. GRB 230805B: Enhanced Swift-XRT position
  14. GRB 230805B: Swift/UVOT Upper Limits
  15. GRB 230805B: Bassano Bresciano observatory upper limit
  16. GRB 230805B: BOOTES-6/DPRT optical upper limit and 1.5m OSN detection
  17. GRB 230805B: NOT optical afterglow confirmation
  18. GRB 230805B: Swift-XRT refined Analysis
  19. Fermi GRB 230805A: Global MASTER-Net observations report
  20. GRB 230805B: SAO RAS optical observations
  21. Swift GRB 230805B: Global MASTER-Net observations report
  22. GRB 230805B: Swift detection of a burst
  23. GRB 230805A: Fermi GBM Final Real-time Localization
  24. GRB 230802B: AstroSat CZTI detection
  25. GRB 230802A: Fermi GBM observation
  26. GRB 230802A: Swift-BAT refined analysis
  27. GRB 230804A: Fermi GBM Final Real-time Localization
  28. IPN triangulation of GRB 230803A
  29. GRB 230802A: Swift/UVOT Upper Limits
  30. GRB 230803A: AstroSat CZTI detection
  31. LIGO/Virgo/KAGRA S230802aq: AstroSat CZTI non-detection and upper limits
  32. GRB 230803A: Fermi GBM Final Real-time Localization
  33. GRB 230802B: Fermi GBM Final Localization
  34. Swift GRB 230802A: Global MASTER-Net observations report
  35. GRB 230802A: BOOTES-5/JGT optical upper limit
  36. LIGO/Virgo/KAGRA S230802aq: Upper limits from Fermi-GBM Observations
  37. GRB 230802A: Swift-XRT refined Analysis
  38. GRB 230802A: Enhanced Swift-XRT position
  39. LIGO/Virgo S230802aq: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  40. GRB 230802A: Swift detection of a burst
  41. LIGO/Virgo/KAGRA S230731an: Upper limits from Swift/BAT-GUANO
  42. GRB 230723A: SPT-3G millimeter-band transient event inconsistent with IPN position
  43. LIGO/Virgo/KAGRA S230731an: AstroSat CZTI non-detection and upper limits
  44. GRB 230731A: Fermi GBM Final Real-time Localization
  45. GRB 230723A: Detection of candidate millimeter-band radiation by SPT-3G
  46. GRB 230728A: Swift-BAT refined analysis
  47. GRB 230723B: Swift-BAT refined analysis
  48. GRB 230723B: MITSuME Ishigaki optical observation
  49. IceCube-230727A: Upper limits from a search for additional neutrino events in IceCube
  50. GRB 230728A: BOOTES-1 optical upper limit
  51. GRB 230728A: Fermi GBM Observation
  52. GRB 230728A: LCOGT Optical Upper Limit
  53. GRB 230728A: Swift/UVOT Upper Limits
  54. GRB 230728A: Swift-XRT refined Analysis
  55. GRB 230728A: Enhanced Swift-XRT position
  56. GRB 230728A: NOT optical observations and possible host galaxy
  57. GRB 230727A: AstroSat CZTI detection
  58. GRB 230728A: Swift detection of a burst
  59. GRB 230727A: Swift/BAT-GUANO detection of a burst
  60. GRB 230727A: Fermi GBM Final Real-time Localization
  61. IceCube-230725A: Upper limits from a search for additional neutrino events in IceCube
  62. IceCube-230724A: Upper limits from a search for additional neutrino events in IceCube
  63. GRB 230723B: Further CAHA observations and host galaxy detection
  64. Konus-Wind detection of GRB 230723A
  65. GRB 230723B: MITSuME Akeno optical afterglow candidate detection
  66. GRB 230723B: ATCA rapid radio follow-up
  67. IBAS trigger number 10337: not a real GRB
  68. GRB 230723B: GAD Observatory, La Spezia, Italy upper limit
  69. IPN triangulation of GRB 230723A (short)
  70. Fermi Gamma-ray Burst Monitor trigger 711982704/230725540 is not a GRB
  71. GRB 230725B: Fermi GBM Final Real-time Localization
  72. GRB 230725A: Fermi GBM Final Real-time Localization
  73. GRB 230723B: Leavitt Observatory upper limit
  74. GRB 230723B: Osservatorio Astronomico Nastro Verde upper limit
  75. GRB 230723B: Montarrenti Observatory upper limit
  76. GRB 230723B: Optical afterglow candidate from CAHA
  77. GRB 230723B: Bassano Bresciano Observatory upper limit
  78. GRB 230723B: Fermi GBM observation
  79. GRB 230723B: Swift-XRT refined Analysis
  80. GRB 230723B: non-detections from Observatoire de Haute-Provence
  81. GRB 230724A: Fermi GBM Final Real-time Localization
  82. GRB 230723B: Optical limit from CAHA
  83. GRB 230723B: Swift/UVOT Upper Limits
  84. Swift GRB 230723B: Global MASTER-Net observations report
  85. Swift-XRT position for GRB 230723B
  86. GRB 230723A: AGILE/MCAL detection
  87. GRB 230723B: Swift-XRT observations
  88. GRB 230723B: Swift detection of a burst
  89. Fermi GRB 230723A: Global MASTER-Net observations report
  90. GRB 230723A: Fermi GBM Final Real-time Localization
  91. IPN triangulation of GRB 230715D
  92. Swift Trigger 1180063 is not a GRB
  93. Swift Trigger 1180060 is not a GRB
  94. Swift Trigger 1180055 is not a GRB
  95. GRB 230718A: Final Localization Correction
  96. GRB 230718A: Fermi GBM Final Real-time Localization
  97. Fermi Gamma-ray Burst Monitor trigger 711329677/230717982 is not a GRB
  98. IPN triangulation of GRB 230712C (short)
  99. IPN triangulation of GRB 230712A (short)
  100. GRB 230717A: Fermi GBM Final Real-time Localization

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