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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"

37764 results found.

  1. GRB 240805B: Enhanced Swift-XRT position
  2. GRB 240805B: LCOGT Optical Upper Limits
  3. Swift GRB 240805B: Global MASTER-Net observations report
  4. GRB 240805B: JinShan optical upper limits
  5. Fermi GRB 240805A: Global MASTER-Net observations report
  6. Swift GRB 240805A: Global MASTER-Net observations report
  7. Fermi Gamma-ray Burst Monitor trigger 744558410/240805574 is not a GRB
  8. GRB 240805A: Swift-XRT refined Analysis
  9. GRB 240805B: Swift detection of a burst
  10. GRB 240805A: Fermi-LAT detection
  11. GRB 240805A: INTEGRAL spectral analysis
  12. EP240801a: Continued optical observations at ZTSh (CraO)
  13. GRB 240805A: A long GRB detected by INTEGRAL
  14. GRB 240805A: Swift detection of a burst
  15. GRB 240805A: Fermi GBM Final Real-time Localization
  16. Fermi GRB 240804A: Global MASTER-Net observations report
  17. EP240802a: Montarrenti Observatory optical upper limit
  18. GRB 240804A: Fermi GBM Final Real-time Localization
  19. Fermi trigger No 744459130: Global MASTER-Net observations report
  20. IPN triangulation of GRB 240802A / EP 240802a
  21. Fermi Gamma-ray Burst Monitor trigger 744459130/240804425 is not a GRB
  22. EP240802A: Bassano Bresciano Observatory upper limit
  23. GRB 240802A: SVOM/GRM observation
  24. EP240802a: Time coincidence with GRB 240802A and optical upper limits with Kinder observations
  25. Fermi trigger No 744278264: Global MASTER-Net observations report
  26. GRB 240802A: AstroSat CZTI detection of a long burst
  27. EP240801a: further SAO RAS optical observations
  28. EP240801a: optical observations at CrAO and AbAO
  29. EP240801a: Leavitt Observatory optical observations
  30. EP240801a: SAO RAS optical observations
  31. GRB 240801B: AstroSat CZTI Updated classification - likely a solar flare
  32. GRB 240727C: SVOM/GRM observation
  33. Fermi GBM trigger 744179961 / 240801194 can not be confirmed as a GRB
  34. GRB 240730A: Swift-BAT refined analysis
  35. Fermi trigger No 744204856: Global MASTER-Net observations report
  36. EP240801a: KAIT optical counterpart observations
  37. GRB 240801B: AstroSat CZTI detection of a bright long burst
  38. Fermi GRB 240801A: Global MASTER-Net observations report
  39. GRB 240801A: Fermi GBM Final Real-time Localization
  40. GRB 240730C: AstroSat CZTI detection of a long burst
  41. GRB 240731A: Fermi GBM Final Localization
  42. Fermi trigger No 744128417: Global MASTER-Net observations report
  43. Fermi trigger No 744083370: Global MASTER-Net observations report
  44. GRB 240731A: AstroSat CZTI detection
  45. GRB 240730A: Osservatorio Astronomico Nastro Verde upper limit
  46. GRB240730A: BOOTES-5/JGT early optical upper limit
  47. Fermi Gamma-ray Burst Monitor trigger 744061103/240730818 is not a GRB
  48. Fermi GRB 240730B: Global MASTER-Net observations report
  49. GRB 240730B: Fermi GBM Final Real-time Localization
  50. Swift GRB 240730A: Global MASTER-Net observations report
  51. GRB 240730A: Swift-XRT refined Analysis
  52. GRB 240715A: Swift-XRT afterglow detection
  53. GRB 240730A: KAIT Optical Upper Limit
  54. GRB 240727C: GRBAlpha detection
  55. GRB 240730A: Swift/UVOT Upper Limits
  56. GRB 240730A: Enhanced Swift-XRT position
  57. GRB 240730A: Swift detection of a burst
  58. Fermi trigger No 743953682: Global MASTER-Net observations report
  59. GRB 240727A: Swift-BAT refined analysis
  60. Fermi Gamma-ray Burst Monitor trigger 743953682/240729575 is not a GRB
  61. GRB 240727A: observations of optical counterpart.
  62. GRB 240727B: Swift-XRT observations
  63. Fermi GRB 240727A: Global MASTER-Net observations report
  64. GRB 240727A: Swift/UVOT detection
  65. Fermi trigger No 743868421: Global MASTER-Net observations report
  66. Fermi Gamma-ray Burst Monitor trigger 743868421/240728588 is not a GRB
  67. GRB 240727A: Correction to time in GCN36960
  68. GRB 240727A: Osservatorio Astronomico Nastro Verde upper limit
  69. GRB 240727A: NOT optical observation
  70. GRB 240727A: JinShan optical upper limits
  71. GRB 240727A Bassano Bresciano Observatory upper limit
  72. GRB 240727D: Correction to the GRB name in GCN 36958
  73. GRB 240727A: Fermi GBM Final Real-time Localization
  74. GRB 240727C: AstroSat CZTI detection of a long burst
  75. GRB 240727A: Swift-XRT refined Analysis
  76. GRB 240720B: GRBAlpha detection
  77. GRB 240718A: GRBAlpha detection
  78. GRB 240710B: GRBAlpha detection
  79. GRB 240627A: GRBAlpha detection
  80. Fermi GRB 240726A: Global MASTER-Net observations report
  81. GRB 240727A: Enhanced Swift-XRT position
  82. GRB 240727B: Fermi GBM Observation
  83. GRB 240727B: Swift ToO observations
  84. GRB 240727B: Swift/BAT-GUANO arcminute localization of a long burst
  85. GRB 240726A: SVOM/GRM observation
  86. GRB 240727B: AstroSat CZTI detection
  87. GRB 240726B: AstroSat CZTI detection of a short burst
  88. GRB240727A: Skynet Optical Afterglow Observations
  89. GRB 240727A: TRT optical afterglow detection
  90. GRB 240727A: KAIT Optical Afterglow Candidate
  91. GRB 240727A: Swift detection of a burst
  92. GRB 240726A: AstroSat CZTI detection of a short burst
  93. GRB 240726A: Fermi GBM Final Real-time Localization
  94. Fermi-LAT gamma-ray observations of IceCube-240725A
  95. IceCube-240725A - IceCube observation of a high-energy neutrino candidate track-like event
  96. Swift Trigger 1244778 is not a GRB
  97. GRB 240720A: Swift-BAT refined analysis
  98. Fermi trigger No 743418632: Global MASTER-Net observations report
  99. Fermi trigger No 743315411: Global MASTER-Net observations report
  100. LIGO/Virgo/KAGRA S240716b: Upper limits from Swift/BAT-GUANO

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