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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"

36390 results found.

  1. GRB 230802A: Swift-BAT refined analysis
  2. GRB 230804A: Fermi GBM Final Real-time Localization
  3. IPN triangulation of GRB 230803A
  4. GRB 230802A: Swift/UVOT Upper Limits
  5. GRB 230803A: AstroSat CZTI detection
  6. LIGO/Virgo/KAGRA S230802aq: AstroSat CZTI non-detection and upper limits
  7. GRB 230803A: Fermi GBM Final Real-time Localization
  8. GRB 230802B: Fermi GBM Final Localization
  9. Swift GRB 230802A: Global MASTER-Net observations report
  10. GRB 230802A: BOOTES-5/JGT optical upper limit
  11. LIGO/Virgo/KAGRA S230802aq: Upper limits from Fermi-GBM Observations
  12. GRB 230802A: Swift-XRT refined Analysis
  13. GRB 230802A: Enhanced Swift-XRT position
  14. LIGO/Virgo S230802aq: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  15. GRB 230802A: Swift detection of a burst
  16. LIGO/Virgo/KAGRA S230731an: Upper limits from Swift/BAT-GUANO
  17. GRB 230723A: SPT-3G millimeter-band transient event inconsistent with IPN position
  18. LIGO/Virgo/KAGRA S230731an: AstroSat CZTI non-detection and upper limits
  19. GRB 230731A: Fermi GBM Final Real-time Localization
  20. GRB 230723A: Detection of candidate millimeter-band radiation by SPT-3G
  21. GRB 230728A: Swift-BAT refined analysis
  22. GRB 230723B: Swift-BAT refined analysis
  23. GRB 230723B: MITSuME Ishigaki optical observation
  24. IceCube-230727A: Upper limits from a search for additional neutrino events in IceCube
  25. GRB 230728A: BOOTES-1 optical upper limit
  26. GRB 230728A: Fermi GBM Observation
  27. GRB 230728A: LCOGT Optical Upper Limit
  28. GRB 230728A: Swift/UVOT Upper Limits
  29. GRB 230728A: Swift-XRT refined Analysis
  30. GRB 230728A: Enhanced Swift-XRT position
  31. GRB 230728A: NOT optical observations and possible host galaxy
  32. GRB 230727A: AstroSat CZTI detection
  33. GRB 230728A: Swift detection of a burst
  34. GRB 230727A: Swift/BAT-GUANO detection of a burst
  35. GRB 230727A: Fermi GBM Final Real-time Localization
  36. IceCube-230725A: Upper limits from a search for additional neutrino events in IceCube
  37. IceCube-230724A: Upper limits from a search for additional neutrino events in IceCube
  38. GRB 230723B: Further CAHA observations and host galaxy detection
  39. Konus-Wind detection of GRB 230723A
  40. GRB 230723B: MITSuME Akeno optical afterglow candidate detection
  41. GRB 230723B: ATCA rapid radio follow-up
  42. IBAS trigger number 10337: not a real GRB
  43. GRB 230723B: GAD Observatory, La Spezia, Italy upper limit
  44. IPN triangulation of GRB 230723A (short)
  45. Fermi Gamma-ray Burst Monitor trigger 711982704/230725540 is not a GRB
  46. GRB 230725B: Fermi GBM Final Real-time Localization
  47. GRB 230725A: Fermi GBM Final Real-time Localization
  48. GRB 230723B: Leavitt Observatory upper limit
  49. GRB 230723B: Osservatorio Astronomico Nastro Verde upper limit
  50. GRB 230723B: Montarrenti Observatory upper limit
  51. GRB 230723B: Optical afterglow candidate from CAHA
  52. GRB 230723B: Bassano Bresciano Observatory upper limit
  53. GRB 230723B: Fermi GBM observation
  54. GRB 230723B: Swift-XRT refined Analysis
  55. GRB 230723B: non-detections from Observatoire de Haute-Provence
  56. GRB 230724A: Fermi GBM Final Real-time Localization
  57. GRB 230723B: Optical limit from CAHA
  58. GRB 230723B: Swift/UVOT Upper Limits
  59. Swift GRB 230723B: Global MASTER-Net observations report
  60. Swift-XRT position for GRB 230723B
  61. GRB 230723A: AGILE/MCAL detection
  62. GRB 230723B: Swift-XRT observations
  63. GRB 230723B: Swift detection of a burst
  64. Fermi GRB 230723A: Global MASTER-Net observations report
  65. GRB 230723A: Fermi GBM Final Real-time Localization
  66. IPN triangulation of GRB 230715D
  67. Swift Trigger 1180063 is not a GRB
  68. Swift Trigger 1180060 is not a GRB
  69. Swift Trigger 1180055 is not a GRB
  70. GRB 230718A: Final Localization Correction
  71. GRB 230718A: Fermi GBM Final Real-time Localization
  72. Fermi Gamma-ray Burst Monitor trigger 711329677/230717982 is not a GRB
  73. IPN triangulation of GRB 230712C (short)
  74. IPN triangulation of GRB 230712A (short)
  75. GRB 230717A: Fermi GBM Final Real-time Localization
  76. GRB 230715A: Fermi GBM Final Real-time Localization
  77. Fermi GRB 230713A: Global MASTER-Net observations report
  78. GRB 230713A: Fermi GBM Final Real-time Localization
  79. GRB 230709B: CALET Gamma-Ray Burst Monitor detection
  80. GRB 230703A: CALET Gamma-Ray Burst Monitor detection
  81. GRB 230709C: Swift/BAT-GUANO detection of a short burst outside the coded FOV
  82. IceCube-230708A: Upper limits from Swift/BAT-GUANO
  83. GRB 230712B: Fermi GBM Final Localization
  84. GRB 230707A: Swift/BAT-GUANO position correction
  85. GRB 230712A: Fermi GBM Final Real-time Localization
  86. GRB 230709C: GRBAlpha detection
  87. GRB 230709B: GRBAlpha detection
  88. GRB 230709C: Fermi GBM Detection
  89. GRB 230709C: Fermi GBM Final Localization
  90. GRB 230707B: Fermi GBM Observation
  91. GRB 230710A: Fermi GBM Final Real-time Localization
  92. GRB 230709C: AstroSat CZTI detection
  93. GRB 230707B: CALET Gamma-Ray Burst Monitor detection
  94. GRB 230703A detected with multiple GRID detectors
  95. GRB 230709C: BALROG localization (Fermi Trigger 710617111 / GRB 230709735)
  96. GRB 230709B: BALROG localization (Fermi Trigger 710614579 / GRB 230709706)
  97. IceCube-230708A: Upper limits from a search for additional neutrino events in IceCube
  98. IceCube-230707B: Upper limits from a search for additional neutrino events in IceCube
  99. IceCube-230707A: Upper limits from a search for additional neutrino events in IceCube
  100. Swift Trigger 1178410: possible GRB 230709A

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