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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"

36425 results found.

  1. Fermi GRB 230812B: Global MASTER-Net observations report
  2. GRB 230812B: Tiled Swift observations
  3. GRB 230812B: Fermi GBM detection of an extremely bright GRB
  4. GRB 230812B: Fermi GBM Final Real-time Localization
  5. ZTF23aaoohpy/AT2023lcr: JWST spectroscopy confirmation of an associated type Ic-BL supernova
  6. GRB 230812A: Fermi GBM Final Real-time Localization
  7. GRB 230808A: Fermi GBM Detection
  8. GRB 230805B: Swift-BAT refined analysis
  9. GRB 230805B: Iota Scorpii Observatory, La Spezia, Italy upper limit
  10. GRB 230805B: AstroSat CZTI detection
  11. GRB 230808A: Swift/BAT-GUANO detection of a burst
  12. GRB 230808B: Fermi GBM Final Real-time Localization
  13. ZTF23aaoohpy/AT2023lcr: JWST observations consistent with the presence of a supernova
  14. GRB 230808A: Fermi GBM Final Real-time Localization
  15. GRB 230805B : MITSuME Akeno optical upper limits
  16. Fermi GRB 230807A: Global MASTER-Net observations report
  17. GRB 230807A: Fermi GBM Final Real-time Localization
  18. LIGO/Virgo/KAGRA S230805x: Upper limits from Swift/BAT-GUANO
  19. Konus-Wind detection of GRB 230803A
  20. GRB 230805B: Fermi GBM observation
  21. GRB 230805B : OHP/T193 optical upper limit
  22. GRB 230806A: Fermi GBM Final Localization
  23. GRB 230805B: Enhanced Swift-XRT position
  24. GRB 230805B: Swift/UVOT Upper Limits
  25. GRB 230805B: Bassano Bresciano observatory upper limit
  26. GRB 230805B: BOOTES-6/DPRT optical upper limit and 1.5m OSN detection
  27. GRB 230805B: NOT optical afterglow confirmation
  28. GRB 230805B: Swift-XRT refined Analysis
  29. Fermi GRB 230805A: Global MASTER-Net observations report
  30. GRB 230805B: SAO RAS optical observations
  31. Swift GRB 230805B: Global MASTER-Net observations report
  32. GRB 230805B: Swift detection of a burst
  33. GRB 230805A: Fermi GBM Final Real-time Localization
  34. GRB 230802B: AstroSat CZTI detection
  35. GRB 230802A: Fermi GBM observation
  36. GRB 230802A: Swift-BAT refined analysis
  37. GRB 230804A: Fermi GBM Final Real-time Localization
  38. IPN triangulation of GRB 230803A
  39. GRB 230802A: Swift/UVOT Upper Limits
  40. GRB 230803A: AstroSat CZTI detection
  41. LIGO/Virgo/KAGRA S230802aq: AstroSat CZTI non-detection and upper limits
  42. GRB 230803A: Fermi GBM Final Real-time Localization
  43. GRB 230802B: Fermi GBM Final Localization
  44. Swift GRB 230802A: Global MASTER-Net observations report
  45. GRB 230802A: BOOTES-5/JGT optical upper limit
  46. LIGO/Virgo/KAGRA S230802aq: Upper limits from Fermi-GBM Observations
  47. GRB 230802A: Swift-XRT refined Analysis
  48. GRB 230802A: Enhanced Swift-XRT position
  49. LIGO/Virgo S230802aq: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  50. GRB 230802A: Swift detection of a burst
  51. LIGO/Virgo/KAGRA S230731an: Upper limits from Swift/BAT-GUANO
  52. GRB 230723A: SPT-3G millimeter-band transient event inconsistent with IPN position
  53. LIGO/Virgo/KAGRA S230731an: AstroSat CZTI non-detection and upper limits
  54. GRB 230731A: Fermi GBM Final Real-time Localization
  55. GRB 230723A: Detection of candidate millimeter-band radiation by SPT-3G
  56. GRB 230728A: Swift-BAT refined analysis
  57. GRB 230723B: Swift-BAT refined analysis
  58. GRB 230723B: MITSuME Ishigaki optical observation
  59. IceCube-230727A: Upper limits from a search for additional neutrino events in IceCube
  60. GRB 230728A: BOOTES-1 optical upper limit
  61. GRB 230728A: Fermi GBM Observation
  62. GRB 230728A: LCOGT Optical Upper Limit
  63. GRB 230728A: Swift/UVOT Upper Limits
  64. GRB 230728A: Swift-XRT refined Analysis
  65. GRB 230728A: Enhanced Swift-XRT position
  66. GRB 230728A: NOT optical observations and possible host galaxy
  67. GRB 230727A: AstroSat CZTI detection
  68. GRB 230728A: Swift detection of a burst
  69. GRB 230727A: Swift/BAT-GUANO detection of a burst
  70. GRB 230727A: Fermi GBM Final Real-time Localization
  71. IceCube-230725A: Upper limits from a search for additional neutrino events in IceCube
  72. IceCube-230724A: Upper limits from a search for additional neutrino events in IceCube
  73. GRB 230723B: Further CAHA observations and host galaxy detection
  74. Konus-Wind detection of GRB 230723A
  75. GRB 230723B: MITSuME Akeno optical afterglow candidate detection
  76. GRB 230723B: ATCA rapid radio follow-up
  77. IBAS trigger number 10337: not a real GRB
  78. GRB 230723B: GAD Observatory, La Spezia, Italy upper limit
  79. IPN triangulation of GRB 230723A (short)
  80. Fermi Gamma-ray Burst Monitor trigger 711982704/230725540 is not a GRB
  81. GRB 230725B: Fermi GBM Final Real-time Localization
  82. GRB 230725A: Fermi GBM Final Real-time Localization
  83. GRB 230723B: Leavitt Observatory upper limit
  84. GRB 230723B: Osservatorio Astronomico Nastro Verde upper limit
  85. GRB 230723B: Montarrenti Observatory upper limit
  86. GRB 230723B: Optical afterglow candidate from CAHA
  87. GRB 230723B: Bassano Bresciano Observatory upper limit
  88. GRB 230723B: Fermi GBM observation
  89. GRB 230723B: Swift-XRT refined Analysis
  90. GRB 230723B: non-detections from Observatoire de Haute-Provence
  91. GRB 230724A: Fermi GBM Final Real-time Localization
  92. GRB 230723B: Optical limit from CAHA
  93. GRB 230723B: Swift/UVOT Upper Limits
  94. Swift GRB 230723B: Global MASTER-Net observations report
  95. Swift-XRT position for GRB 230723B
  96. GRB 230723A: AGILE/MCAL detection
  97. GRB 230723B: Swift-XRT observations
  98. GRB 230723B: Swift detection of a burst
  99. Fermi GRB 230723A: Global MASTER-Net observations report
  100. GRB 230723A: Fermi GBM Final Real-time Localization

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