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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"

36380 results found.

  1. LIGO/Virgo/KAGRA S230802aq: Upper limits from Fermi-GBM Observations
  2. GRB 230802A: Swift-XRT refined Analysis
  3. GRB 230802A: Enhanced Swift-XRT position
  4. LIGO/Virgo S230802aq: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  5. GRB 230802A: Swift detection of a burst
  6. LIGO/Virgo/KAGRA S230731an: Upper limits from Swift/BAT-GUANO
  7. GRB 230723A: SPT-3G millimeter-band transient event inconsistent with IPN position
  8. LIGO/Virgo/KAGRA S230731an: AstroSat CZTI non-detection and upper limits
  9. GRB 230731A: Fermi GBM Final Real-time Localization
  10. GRB 230723A: Detection of candidate millimeter-band radiation by SPT-3G
  11. GRB 230728A: Swift-BAT refined analysis
  12. GRB 230723B: Swift-BAT refined analysis
  13. GRB 230723B: MITSuME Ishigaki optical observation
  14. IceCube-230727A: Upper limits from a search for additional neutrino events in IceCube
  15. GRB 230728A: BOOTES-1 optical upper limit
  16. GRB 230728A: Fermi GBM Observation
  17. GRB 230728A: LCOGT Optical Upper Limit
  18. GRB 230728A: Swift/UVOT Upper Limits
  19. GRB 230728A: Swift-XRT refined Analysis
  20. GRB 230728A: Enhanced Swift-XRT position
  21. GRB 230728A: NOT optical observations and possible host galaxy
  22. GRB 230727A: AstroSat CZTI detection
  23. GRB 230728A: Swift detection of a burst
  24. GRB 230727A: Swift/BAT-GUANO detection of a burst
  25. GRB 230727A: Fermi GBM Final Real-time Localization
  26. IceCube-230725A: Upper limits from a search for additional neutrino events in IceCube
  27. IceCube-230724A: Upper limits from a search for additional neutrino events in IceCube
  28. GRB 230723B: Further CAHA observations and host galaxy detection
  29. Konus-Wind detection of GRB 230723A
  30. GRB 230723B: MITSuME Akeno optical afterglow candidate detection
  31. GRB 230723B: ATCA rapid radio follow-up
  32. IBAS trigger number 10337: not a real GRB
  33. GRB 230723B: GAD Observatory, La Spezia, Italy upper limit
  34. IPN triangulation of GRB 230723A (short)
  35. Fermi Gamma-ray Burst Monitor trigger 711982704/230725540 is not a GRB
  36. GRB 230725B: Fermi GBM Final Real-time Localization
  37. GRB 230725A: Fermi GBM Final Real-time Localization
  38. GRB 230723B: Leavitt Observatory upper limit
  39. GRB 230723B: Osservatorio Astronomico Nastro Verde upper limit
  40. GRB 230723B: Montarrenti Observatory upper limit
  41. GRB 230723B: Optical afterglow candidate from CAHA
  42. GRB 230723B: Bassano Bresciano Observatory upper limit
  43. GRB 230723B: Fermi GBM observation
  44. GRB 230723B: Swift-XRT refined Analysis
  45. GRB 230723B: non-detections from Observatoire de Haute-Provence
  46. GRB 230724A: Fermi GBM Final Real-time Localization
  47. GRB 230723B: Optical limit from CAHA
  48. GRB 230723B: Swift/UVOT Upper Limits
  49. Swift GRB 230723B: Global MASTER-Net observations report
  50. Swift-XRT position for GRB 230723B
  51. GRB 230723A: AGILE/MCAL detection
  52. GRB 230723B: Swift-XRT observations
  53. GRB 230723B: Swift detection of a burst
  54. Fermi GRB 230723A: Global MASTER-Net observations report
  55. GRB 230723A: Fermi GBM Final Real-time Localization
  56. IPN triangulation of GRB 230715D
  57. Swift Trigger 1180063 is not a GRB
  58. Swift Trigger 1180060 is not a GRB
  59. Swift Trigger 1180055 is not a GRB
  60. GRB 230718A: Final Localization Correction
  61. GRB 230718A: Fermi GBM Final Real-time Localization
  62. Fermi Gamma-ray Burst Monitor trigger 711329677/230717982 is not a GRB
  63. IPN triangulation of GRB 230712C (short)
  64. IPN triangulation of GRB 230712A (short)
  65. GRB 230717A: Fermi GBM Final Real-time Localization
  66. GRB 230715A: Fermi GBM Final Real-time Localization
  67. Fermi GRB 230713A: Global MASTER-Net observations report
  68. GRB 230713A: Fermi GBM Final Real-time Localization
  69. GRB 230709B: CALET Gamma-Ray Burst Monitor detection
  70. GRB 230703A: CALET Gamma-Ray Burst Monitor detection
  71. GRB 230709C: Swift/BAT-GUANO detection of a short burst outside the coded FOV
  72. IceCube-230708A: Upper limits from Swift/BAT-GUANO
  73. GRB 230712B: Fermi GBM Final Localization
  74. GRB 230707A: Swift/BAT-GUANO position correction
  75. GRB 230712A: Fermi GBM Final Real-time Localization
  76. GRB 230709C: GRBAlpha detection
  77. GRB 230709B: GRBAlpha detection
  78. GRB 230709C: Fermi GBM Detection
  79. GRB 230709C: Fermi GBM Final Localization
  80. GRB 230707B: Fermi GBM Observation
  81. GRB 230710A: Fermi GBM Final Real-time Localization
  82. GRB 230709C: AstroSat CZTI detection
  83. GRB 230707B: CALET Gamma-Ray Burst Monitor detection
  84. GRB 230703A detected with multiple GRID detectors
  85. GRB 230709C: BALROG localization (Fermi Trigger 710617111 / GRB 230709735)
  86. GRB 230709B: BALROG localization (Fermi Trigger 710614579 / GRB 230709706)
  87. IceCube-230708A: Upper limits from a search for additional neutrino events in IceCube
  88. IceCube-230707B: Upper limits from a search for additional neutrino events in IceCube
  89. IceCube-230707A: Upper limits from a search for additional neutrino events in IceCube
  90. Swift Trigger 1178410: possible GRB 230709A
  91. GRB 230628C: GRID Detection
  92. GRB 230707B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  93. GRB 230707A: Swift-XRT observations
  94. GRB 230707B: Fermi GBM Final Real-time Localization
  95. GRB 230707A: Fermi GBM Detection
  96. GRB 230707A: Swift ToO observations
  97. GRB 230707A: Swift/BAT-GUANO arcminute localization of a burst
  98. Fermi GRB 230707A: Global MASTER-Net observations report
  99. GRB 230707A: Fermi GBM Final Real-time Localization
  100. IBAS trigger number 10311: not a real GRB

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