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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"

37770 results found.

  1. GRB 230626A: GRBAlpha detection
  2. LIGO/Virgo/KAGRA S230527c: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  3. LIGO/Virgo/KAGRA S230627c: Upper limits from Fermi-GBM Observations
  4. GRB230626A: Fermi GBM Detection
  5. Konus-Wind detection of GRB 230616A
  6. GRB 230618A: Swift-BAT refined analysis
  7. GRB 230625B: Swift/BAT-GUANO detection of a long burst
  8. GRB 230622A: Swift-BAT refined analysis
  9. GRB 230623A: Swift-XRT observations
  10. GRB 230625A: Fermi GBM Final Real-time Localization
  11. INTEGRAL upper limit on any GRB associated with ZTF23aaoohpy/AT2023lcr
  12. ATLAS23msn/ZTF23aaoohpy/AT2023lcr: Zeiss-1000 of Koshka observatory optical observations
  13. GRB 230623B: Swift/BAT-GUANO detection of a long burst outside the coded FOV 
  14. GRB 230623A: Tiled Swift observations
  15. MAXI GRB 230623A: MASTER optical observations
  16. GRB 230623A: Tiled Swift observations
  17. GRB 230622A: ATCA rapid radio follow-up
  18. GRB 230622A: Swift-XRT refined Analysis
  19. GRB 230623A: MAXI/GSC detection
  20. Swift GRB 230622A: Global MASTER-Net observations report
  21. Fermi GBM-230619: AstroSat CZTI non-detection and upper limits for the sub-threshold candidate
  22. GRB 230622A: Swift detection of a burst
  23. GRB 230621A: Fermi GBM Final Localization Correction
  24. Fermi trigger No 709083929: Global MASTER-Net observations report
  25. Fermi GBM-230619: A soft subthreshold candidate potentially associated with a subthreshold LIGO/Virgo compact binary merger candidate
  26. ZTF23aaoohpy/AT2023lcr: Montarrenti Observatory optical observations
  27. ZTF23aaoohpy (AT2023lcr/ATLAS23msn): Upper limits from Konus-Wind observations
  28. ZTF23aaoohpy/AT2023lc: Mondy optical observations
  29. IPN triangulation of GRB 230616A (short)
  30. AT2023lcr (ATLAS23msn/ZTF23aaoohpy): Kinder observations with Lulin observatory and a probable plateau in the g-band light curve
  31. ZTF23aaoohpy/AT2023lcr: Keck/LRIS spectroscopy and redshift
  32. ZTF23aaoohpy/AT2023lcr: Liverpool Telescope detection
  33. GRB 230618A: Osservatorio Astronomico Nastro verde upper limit
  34. GRB 230618A: Enhanced Swift-XRT position
  35. GRB 230618A: Swift/UVOT Upper Limits
  36. GRB 230618A: Swift-XRT refined Analysis
  37. GRB 230616A: Swift-XRT observations
  38. GRB 230618A: KAIT Optical Observations
  39. Swift GRB 230618A: Global MASTER-Net observations report
  40. GRB230618A: LCOGT Optical Observations
  41. GRB 230618B: Fermi GBM Final Real-time Localization
  42. GRB 230618A: Prompt enhanced Swift-XRT position
  43. GRB 230618A: Swift detection of a burst
  44. GRB 230616A: Swift ToO observations
  45. GRB 230617A: Fermi GBM Final Real-time Localization
  46. GRB 230614C: GRBAlpha detection
  47. GRB 230616A: AstroSat CZTI detection
  48. GRB 230616A: Swift/BAT-GUANO detection of a short burst outside the coded FOV
  49. GRB 230614C: AstroSat CZTI detection
  50. GRB 230614B: Fermi GBM Observation
  51. GRB 230614C: Fermi GBM Detection
  52. GRB 230614B: Swift/BAT-GUANO detection outside the coded FOV
  53. Fermi trigger No 708426906: Global MASTER-Net observations report
  54. GRB 230614B: Fermi GBM Final Real-time Localization
  55. GRB 230614A: Fermi GBM Final Real-time Localization
  56. GRB 230606A: LCOGT Optical Observations
  57. GRB 230608A: CALET Gamma-Ray Burst Monitor detection
  58. GRB 230608A: AstroSat CZTI detection
  59. GRB 230608A: AGILE detection
  60. Fermi GRB 230603A: Global MASTER-Net observations report
  61. Fermi trigger No 707039690: Global MASTER-Net observations report
  62. GRB 230506B: Chandra localization of the X-ray afterglow
  63. GRB 230606A: Swift-BAT refined analysis
  64. GRB 230606A: Gaoyazi/GOT optical upper limit
  65. GRB 230606A: Fermi GBM Observation
  66. GRB 230606A: BOOTES-5/JGT optical upper limit
  67. GRB 230606A: Swift-XRT refined Analysis
  68. GRB 230604A: GRBAlpha detection
  69. GRB 230606A: Swift/UVOT Upper Limits
  70. GRB 230606A: Enhanced Swift-XRT position
  71. GRB 230606A: Swift detection of a burst
  72. Fermi-LAT gamma-ray observations of IceCube-230603A
  73. GRB 230604A: AstroSat CZTI detection of a short GRB
  74. IceCube-230603A - IceCube observation of a high-energy neutrino candidate track-like event
  75. GRB 230603A: Fermi GBM Final Real-time Localization
  76. GRB 230521A: VZLUSAT-2 detection
  77. GRB 230522A: GRBAlpha and VZLUSAT-2 joint detection
  78. GRB 230525A: CALET Gamma-Ray Burst Monitor detection
  79. LIGO/Virgo/KAGRA S230529ay: Upper limits from Fermi-GBM Observations
  80. LIGO/Virgo/KAGRA S230529ay: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  81. GRB 230529A: Fermi GBM Final Real-time Localization
  82. Fermi-LAT gamma-ray observations of IceCube-230524A
  83. LIGO/Virgo/KAGRA S230518h: Upper limits from Glowbug gamma-ray observations
  84. GRB 230510A: Swift-BAT refined analysis
  85. GRB 230525A: Fermi GBM Detection
  86. GRB 230525A: Fermi GBM Final Localization
  87. GRB 230523B: GRBAlpha detection
  88. GRB 230524A: Fermi GBM Observation
  89. IceCube-230524A - IceCube observation of a high-energy neutrino candidate track-like event
  90. GRB 230524B: AstroSat CZTI detection
  91. GRB 230524A: AstroSat CZTI detection
  92. GRB 230524A: AGILE detection
  93. Fermi trigger No 706610076: Global MASTER-Net observations report
  94. GRB 230524A: Fermi GBM Final Real-time Localization
  95. Fermi trigger No 706599831: Global MASTER-Net observations report
  96. Fermi trigger No 706536788: Global MASTER-Net observations report
  97. GRB 230523B: Name correction from GCN Circular 33859
  98. GRB 230523A: Swift/BAT-GUANO detection of a short hard burst
  99. Fermi Gamma-ray Burst Monitor trigger 706536788/230523509 is not a GRB
  100. GRB 230523A: Fermi GBM Final Real-time Localization

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