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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"

24542 results found.

  1. Swift GRB230816.80: Global MASTER-Net observations report
  2. IPN triangulation of GRB 230815B
  3. Swift GRB230816.67: Global MASTER-Net observations report
  4. GRB 230815A: Swift-BAT refined analysis
  5. GRB 230815B: GECAM-B and GECAM-C detection of a burst
  6. GRB 230815A: Swift-XRT refined Analysis
  7. GRB 230812B: iTelescope optical upper limit
  8. GRB 230815A: Fermi GBM detection
  9. Swift GRB 230815A: Global MASTER-Net observations report
  10. Fermi GRB 230814A: Global MASTER-Net observations report
  11. GRB 230815A: Swift detection of a burst
  12. LIGO/Virgo/KAGRA S230814ah: Identification of a GW compact binary merger candidate
  13. GRB 230812B: Upper limits from a neutrino search with IceCube
  14. LIGO/Virgo/KAGRA S230814r: Updated Sky localization
  15. GRB 230812B: GRANDMA further observations of ZTF23aaxeacr candidate afterglow
  16. GRB 230814A: BALROG localization (Fermi Trigger 713732101 / GRB 230814788)
  17. GRB 230814A: Fermi GBM Final Real-time Localization
  18. GRB 230812B: GIT optical follow-up
  19. GRB 230812B: Leavitt Observatory optical observations
  20. GRB 230812B: rest-frame energetics from Konus-Wind observation
  21. LIGO/Virgo/KAGRA S230814r: Identification of a GW compact binary merger candidate
  22. GRB 230812B: Redshift from OSIRIS+/GTC
  23. LIGO/Virgo/KAGRA S230812aj: two counterpart neutrino candidates from IceCube neutrino searches
  24. GRB 230812B: Detected Optical Afterglow Candidate
  25. Konus-Wind detection of GRB 230812B
  26. GRB230812B: AGILE/MCAL detection
  27. GRB 230812B: GECAM-C observation of a very bright burst
  28. GRB 230812B: Swift-XRT afterglow detection
  29. GRB 230812B: Zwicky Transient Facility Identifies Optical Afterglow Candidate of a Fermi GRB (Trigger 713559497)
  30. GRB 230812B: KAIT Optical Afterglow Candidate
  31. GRB 230812B: Improved Swift/XRT localization
  32. GRB 230812B: Preliminary Swift/XRT localization
  33. GRB 230812B: Fermi-LAT detection
  34. GRB 230812B: Fermi GBM Observation of a very bright burst
  35. LAT GRB230812.79: Global MASTER-Net observations report
  36. Fermi GRB 230812B: Global MASTER-Net observations report
  37. GRB 230812B: Fermi GBM detection of an extremely bright GRB
  38. GRB 230812B: Fermi GBM Final Real-time Localization
  39. Fermi trigger No 713525317: Global MASTER-Net observations report
  40. GRB 230812A: Fermi GBM Final Real-time Localization
  41. LIGO/Virgo/KAGRA S230811n: Updated Sky localization
  42. GRB 230808A: Fermi GBM Detection
  43. LIGO/Virgo/KAGRA S230811n: Identification of a GW compact binary merger candidate
  44. GRB 230805B: Swift-BAT refined analysis
  45. LIGO/Virgo/KAGRA S230810af: Retraction of GW compact binary merger candidate
  46. GRB 230808A: Swift/BAT-GUANO detection of a burst
  47. Fermi trigger No 713136868: Global MASTER-Net observations report
  48. GRB 230808B: Fermi GBM Final Real-time Localization
  49. Fermi trigger No 713205976: Global MASTER-Net observations report
  50. GRB 230808A: Fermi GBM Final Real-time Localization
  51. GRB 230805B : MITSuME Akeno optical upper limits
  52. LIGO/Virgo/KAGRA S230808i: Identification of a GW unmodeled transient candidate
  53. LIGO/Virgo/KAGRA S230807f: Updated Sky localization and EM Bright Classification
  54. Fermi GRB 230807A: Global MASTER-Net observations report
  55. Fermi trigger No 713134237: Global MASTER-Net observations report
  56. GRB 230807A: Fermi GBM Final Real-time Localization
  57. LIGO/Virgo/KAGRA S230807f: Identification of a GW compact binary merger candidate
  58. LIGO/Virgo/KAGRA S230805x: Upper limits from Swift/BAT-GUANO
  59. Konus-Wind detection of GRB 230803A
  60. GRB 230805B: Fermi GBM observation
  61. GRB 230805B : OHP/T193 optical upper limit
  62. LIGO/Virgo/KAGRA S230806ak: Updated Sky localization and EM Bright Classification
  63. GRB 230806A: Fermi GBM Final Localization
  64. LIGO/Virgo/KAGRA S230806ak: Identification of a GW compact binary merger candidate
  65. Fermi trigger No 712991593: Global MASTER-Net observations report
  66. Fermi trigger No 712987357: Global MASTER-Net observations report
  67. Fermi GRB 230805A: Global MASTER-Net observations report
  68. Fermi trigger No 712927418: Global MASTER-Net observations report
  69. Swift GRB 230805B: Global MASTER-Net observations report
  70. LIGO/Virgo/KAGRA S230805x: Updated Sky localization
  71. GRB 230805A: Fermi GBM Final Real-time Localization
  72. LIGO/Virgo/KAGRA S230805x: Identification of a GW compact binary merger candidate
  73. LIGO/Virgo/KAGRA S230802aq: Updated Sky localization and EM Bright Classification
  74. GRB 230802A: Fermi GBM observation
  75. GRB 230802A: Swift-BAT refined analysis
  76. GRB 230804A: Fermi GBM Final Real-time Localization
  77. Fermi trigger No 712798043: Global MASTER-Net observations report
  78. IPN triangulation of GRB 230803A
  79. LIGO/Virgo/KAGRA S230802aq: AstroSat CZTI non-detection and upper limits
  80. Fermi trigger No 712718833: Global MASTER-Net observations report
  81. GRB 230803A: Fermi GBM Final Real-time Localization
  82. Fermi trigger No 712713532: Global MASTER-Net observations report
  83. Fermi trigger No 712651827: Global MASTER-Net observations report
  84. GRB 230802B: Fermi GBM Final Localization
  85. Swift GRB 230802A: Global MASTER-Net observations report
  86. LIGO/Virgo/KAGRA S230802aq: Upper limits from Fermi-GBM Observations
  87. LIGO/Virgo S230802aq: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  88. LIGO/Virgo/KAGRA S230802aq: Coverage and upper limits from MAXI/GSC observations
  89. LIGO/Virgo/KAGRA S230802aq: Identification of a GW compact binary merger candidate
  90. IceCube-230724A: JCMT/SCUBA-2 submm observations
  91. LIGO/Virgo/KAGRA S230731an: Upper limits from Swift/BAT-GUANO
  92. LIGO/Virgo/KAGRA S230731an: AstroSat CZTI non-detection and upper limits
  93. LIGO/Virgo/KAGRA S230731an: not observable by Fermi-GBM
  94. LIGO/Virgo/KAGRA S230731an: Updated Sky Localization and EM Bright Classification, and Correction to Source Classification
  95. GRB 230731A: Fermi GBM Final Real-time Localization
  96. LIGO/Virgo/KAGRA S230731an: Coverage and upper limits from MAXI/GSC observations
  97. LIGO/Virgo/KAGRA S230731an: Identification of a GW compact binary merger candidate
  98. LIGO/Virgo/KAGRA S230729z: Updated Sky localization
  99. GRB 230723A: Detection of candidate millimeter-band radiation by SPT-3G
  100. Fermi trigger No 712390645: Global MASTER-Net observations report

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