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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"

36367 results found.

  1. GRB 240805B: NUTTelA-TAO / BSTI Optical Limits
  2. GRB 240805B: Swift-XRT refined Analysis
  3. GRB 240805B: Swift/UVOT Upper Limits
  4. GRB 240805A: Swift/UVOT Upper Limits
  5. GRB 240805B: BTA optical afterglow candidate
  6. GRB 240805A: SVOM/GRM observation
  7. GRB 240805B: Enhanced Swift-XRT position
  8. GRB 240805B: LCOGT Optical Upper Limits
  9. Swift GRB 240805B: Global MASTER-Net observations report
  10. GRB 240805B: JinShan optical upper limits
  11. Fermi GRB 240805A: Global MASTER-Net observations report
  12. Swift GRB 240805A: Global MASTER-Net observations report
  13. Fermi Gamma-ray Burst Monitor trigger 744558410/240805574 is not a GRB
  14. GRB 240805A: Swift-XRT refined Analysis
  15. GRB 240805B: Swift detection of a burst
  16. GRB 240805A: Fermi-LAT detection
  17. GRB 240805A: INTEGRAL spectral analysis
  18. EP240801a: Continued optical observations at ZTSh (CraO)
  19. GRB 240805A: A long GRB detected by INTEGRAL
  20. GRB 240805A: Swift detection of a burst
  21. GRB 240805A: Fermi GBM Final Real-time Localization
  22. Fermi GRB 240804A: Global MASTER-Net observations report
  23. EP240802a: Montarrenti Observatory optical upper limit
  24. GRB 240804A: Fermi GBM Final Real-time Localization
  25. IPN triangulation of GRB 240802A / EP 240802a
  26. Fermi Gamma-ray Burst Monitor trigger 744459130/240804425 is not a GRB
  27. EP240802A: Bassano Bresciano Observatory upper limit
  28. GRB 240802A: SVOM/GRM observation
  29. EP240802a: Time coincidence with GRB 240802A and optical upper limits with Kinder observations
  30. GRB 240802A: AstroSat CZTI detection of a long burst
  31. EP240801a: further SAO RAS optical observations
  32. EP240801a: optical observations at CrAO and AbAO
  33. EP240801a: Leavitt Observatory optical observations
  34. EP240801a: SAO RAS optical observations
  35. GRB 240801B: AstroSat CZTI Updated classification - likely a solar flare
  36. GRB 240727C: SVOM/GRM observation
  37. Fermi GBM trigger 744179961 / 240801194 can not be confirmed as a GRB
  38. GRB 240730A: Swift-BAT refined analysis
  39. EP240801a: KAIT optical counterpart observations
  40. GRB 240801B: AstroSat CZTI detection of a bright long burst
  41. Fermi GRB 240801A: Global MASTER-Net observations report
  42. GRB 240801A: Fermi GBM Final Real-time Localization
  43. GRB 240730C: AstroSat CZTI detection of a long burst
  44. GRB 240731A: Fermi GBM Final Localization
  45. GRB 240731A: AstroSat CZTI detection
  46. GRB 240730A: Osservatorio Astronomico Nastro Verde upper limit
  47. GRB240730A: BOOTES-5/JGT early optical upper limit
  48. Fermi Gamma-ray Burst Monitor trigger 744061103/240730818 is not a GRB
  49. Fermi GRB 240730B: Global MASTER-Net observations report
  50. GRB 240730B: Fermi GBM Final Real-time Localization
  51. Swift GRB 240730A: Global MASTER-Net observations report
  52. GRB 240730A: Swift-XRT refined Analysis
  53. GRB 240715A: Swift-XRT afterglow detection
  54. GRB 240730A: KAIT Optical Upper Limit
  55. GRB 240727C: GRBAlpha detection
  56. GRB 240730A: Swift/UVOT Upper Limits
  57. GRB 240730A: Enhanced Swift-XRT position
  58. GRB 240730A: Swift detection of a burst
  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 Gamma-ray Burst Monitor trigger 743868421/240728588 is not a GRB
  66. GRB 240727A: Correction to time in GCN36960
  67. GRB 240727A: Osservatorio Astronomico Nastro Verde upper limit
  68. GRB 240727A: NOT optical observation
  69. GRB 240727A: JinShan optical upper limits
  70. GRB 240727A Bassano Bresciano Observatory upper limit
  71. GRB 240727D: Correction to the GRB name in GCN 36958
  72. GRB 240727A: Fermi GBM Final Real-time Localization
  73. GRB 240727C: AstroSat CZTI detection of a long burst
  74. GRB 240727A: Swift-XRT refined Analysis
  75. GRB 240720B: GRBAlpha detection
  76. GRB 240718A: GRBAlpha detection
  77. GRB 240710B: GRBAlpha detection
  78. GRB 240627A: GRBAlpha detection
  79. Fermi GRB 240726A: Global MASTER-Net observations report
  80. GRB 240727A: Enhanced Swift-XRT position
  81. GRB 240727B: Fermi GBM Observation
  82. GRB 240727B: Swift ToO observations
  83. GRB 240727B: Swift/BAT-GUANO arcminute localization of a long burst
  84. GRB 240726A: SVOM/GRM observation
  85. GRB 240727B: AstroSat CZTI detection
  86. GRB 240726B: AstroSat CZTI detection of a short burst
  87. GRB240727A: Skynet Optical Afterglow Observations
  88. GRB 240727A: TRT optical afterglow detection
  89. GRB 240727A: KAIT Optical Afterglow Candidate
  90. GRB 240727A: Swift detection of a burst
  91. GRB 240726A: AstroSat CZTI detection of a short burst
  92. IceCube-240725A: Upper limits from a search for additional neutrino events in IceCube
  93. GRB 240726A: Fermi GBM Final Real-time Localization
  94. Swift Trigger 1244778 is not a GRB
  95. GRB 240720A: Swift-BAT refined analysis
  96. IceCube-240721A: Upper limits from a search for additional neutrino events in IceCube
  97. LIGO/Virgo/KAGRA S240716b: Upper limits from Swift/BAT-GUANO
  98. LIGO/Virgo/KAGRA S240703ad: Upper limits from Swift/BAT-GUANO
  99. Fermi Gamma-ray Burst Monitor trigger 743271526/240721680 is not a GRB
  100. Fermi Gamma-ray Burst Monitor trigger 743243582/240721356 (GRB 240721A) is not a GRB

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