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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"

36422 results found.

  1. GRB 230812B: Fermi GBM Final Real-time Localization
  2. ZTF23aaoohpy/AT2023lcr: JWST spectroscopy confirmation of an associated type Ic-BL supernova
  3. GRB 230812A: Fermi GBM Final Real-time Localization
  4. GRB 230808A: Fermi GBM Detection
  5. GRB 230805B: Swift-BAT refined analysis
  6. GRB 230805B: Iota Scorpii Observatory, La Spezia, Italy upper limit
  7. GRB 230805B: AstroSat CZTI detection
  8. GRB 230808A: Swift/BAT-GUANO detection of a burst
  9. GRB 230808B: Fermi GBM Final Real-time Localization
  10. ZTF23aaoohpy/AT2023lcr: JWST observations consistent with the presence of a supernova
  11. GRB 230808A: Fermi GBM Final Real-time Localization
  12. GRB 230805B : MITSuME Akeno optical upper limits
  13. Fermi GRB 230807A: Global MASTER-Net observations report
  14. GRB 230807A: Fermi GBM Final Real-time Localization
  15. LIGO/Virgo/KAGRA S230805x: Upper limits from Swift/BAT-GUANO
  16. Konus-Wind detection of GRB 230803A
  17. GRB 230805B: Fermi GBM observation
  18. GRB 230805B : OHP/T193 optical upper limit
  19. GRB 230806A: Fermi GBM Final Localization
  20. GRB 230805B: Enhanced Swift-XRT position
  21. GRB 230805B: Swift/UVOT Upper Limits
  22. GRB 230805B: Bassano Bresciano observatory upper limit
  23. GRB 230805B: BOOTES-6/DPRT optical upper limit and 1.5m OSN detection
  24. GRB 230805B: NOT optical afterglow confirmation
  25. GRB 230805B: Swift-XRT refined Analysis
  26. Fermi GRB 230805A: Global MASTER-Net observations report
  27. GRB 230805B: SAO RAS optical observations
  28. Swift GRB 230805B: Global MASTER-Net observations report
  29. GRB 230805B: Swift detection of a burst
  30. GRB 230805A: Fermi GBM Final Real-time Localization
  31. GRB 230802B: AstroSat CZTI detection
  32. GRB 230802A: Fermi GBM observation
  33. GRB 230802A: Swift-BAT refined analysis
  34. GRB 230804A: Fermi GBM Final Real-time Localization
  35. IPN triangulation of GRB 230803A
  36. GRB 230802A: Swift/UVOT Upper Limits
  37. GRB 230803A: AstroSat CZTI detection
  38. LIGO/Virgo/KAGRA S230802aq: AstroSat CZTI non-detection and upper limits
  39. GRB 230803A: Fermi GBM Final Real-time Localization
  40. GRB 230802B: Fermi GBM Final Localization
  41. Swift GRB 230802A: Global MASTER-Net observations report
  42. GRB 230802A: BOOTES-5/JGT optical upper limit
  43. LIGO/Virgo/KAGRA S230802aq: Upper limits from Fermi-GBM Observations
  44. GRB 230802A: Swift-XRT refined Analysis
  45. GRB 230802A: Enhanced Swift-XRT position
  46. LIGO/Virgo S230802aq: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  47. GRB 230802A: Swift detection of a burst
  48. LIGO/Virgo/KAGRA S230731an: Upper limits from Swift/BAT-GUANO
  49. GRB 230723A: SPT-3G millimeter-band transient event inconsistent with IPN position
  50. LIGO/Virgo/KAGRA S230731an: AstroSat CZTI non-detection and upper limits
  51. GRB 230731A: Fermi GBM Final Real-time Localization
  52. GRB 230723A: Detection of candidate millimeter-band radiation by SPT-3G
  53. GRB 230728A: Swift-BAT refined analysis
  54. GRB 230723B: Swift-BAT refined analysis
  55. GRB 230723B: MITSuME Ishigaki optical observation
  56. IceCube-230727A: Upper limits from a search for additional neutrino events in IceCube
  57. GRB 230728A: BOOTES-1 optical upper limit
  58. GRB 230728A: Fermi GBM Observation
  59. GRB 230728A: LCOGT Optical Upper Limit
  60. GRB 230728A: Swift/UVOT Upper Limits
  61. GRB 230728A: Swift-XRT refined Analysis
  62. GRB 230728A: Enhanced Swift-XRT position
  63. GRB 230728A: NOT optical observations and possible host galaxy
  64. GRB 230727A: AstroSat CZTI detection
  65. GRB 230728A: Swift detection of a burst
  66. GRB 230727A: Swift/BAT-GUANO detection of a burst
  67. GRB 230727A: Fermi GBM Final Real-time Localization
  68. IceCube-230725A: Upper limits from a search for additional neutrino events in IceCube
  69. IceCube-230724A: Upper limits from a search for additional neutrino events in IceCube
  70. GRB 230723B: Further CAHA observations and host galaxy detection
  71. Konus-Wind detection of GRB 230723A
  72. GRB 230723B: MITSuME Akeno optical afterglow candidate detection
  73. GRB 230723B: ATCA rapid radio follow-up
  74. IBAS trigger number 10337: not a real GRB
  75. GRB 230723B: GAD Observatory, La Spezia, Italy upper limit
  76. IPN triangulation of GRB 230723A (short)
  77. Fermi Gamma-ray Burst Monitor trigger 711982704/230725540 is not a GRB
  78. GRB 230725B: Fermi GBM Final Real-time Localization
  79. GRB 230725A: Fermi GBM Final Real-time Localization
  80. GRB 230723B: Leavitt Observatory upper limit
  81. GRB 230723B: Osservatorio Astronomico Nastro Verde upper limit
  82. GRB 230723B: Montarrenti Observatory upper limit
  83. GRB 230723B: Optical afterglow candidate from CAHA
  84. GRB 230723B: Bassano Bresciano Observatory upper limit
  85. GRB 230723B: Fermi GBM observation
  86. GRB 230723B: Swift-XRT refined Analysis
  87. GRB 230723B: non-detections from Observatoire de Haute-Provence
  88. GRB 230724A: Fermi GBM Final Real-time Localization
  89. GRB 230723B: Optical limit from CAHA
  90. GRB 230723B: Swift/UVOT Upper Limits
  91. Swift GRB 230723B: Global MASTER-Net observations report
  92. Swift-XRT position for GRB 230723B
  93. GRB 230723A: AGILE/MCAL detection
  94. GRB 230723B: Swift-XRT observations
  95. GRB 230723B: Swift detection of a burst
  96. Fermi GRB 230723A: Global MASTER-Net observations report
  97. GRB 230723A: Fermi GBM Final Real-time Localization
  98. IPN triangulation of GRB 230715D
  99. Swift Trigger 1180063 is not a GRB
  100. Swift Trigger 1180060 is not a GRB

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