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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"

45684 results found.

  1. GRB 240802A: AstroSat CZTI detection of a long burst
  2. EP240801a: further SAO RAS optical observations
  3. EP240801a: optical observations at CrAO and AbAO
  4. EP240801a: GRANDMA and Kilonova-Catcher optical observations
  5. EP240801a: Leavitt Observatory optical observations
  6. EP240801a: GTC spectroscopy and absorption redshift
  7. EP240801a: SAO RAS optical observations
  8. GRB 240801B: AstroSat CZTI Updated classification - likely a solar flare
  9. EP240801a: JinShan optical observations
  10. GRB 240727C: SVOM/GRM observation
  11. EP240801a: NOT optical observations
  12. EP240801a: follow-up observation with LCOGT
  13. Fermi GBM trigger 744179961 / 240801194 can not be confirmed as a GRB
  14. GRB 240730A: Swift-BAT refined analysis
  15. EP240801a: GSP follow-up observations of the candidate counterpart
  16. Fermi trigger No 744204856: Global MASTER-Net observations report
  17. EP240801a: Kinder follow-up observations of the candidate counterpart
  18. EP240708a: Kinder follow-up observations of the candidate counterpart (duplicate submission of GCN 37002)
  19. EP240801a: KAIT optical counterpart observations
  20. EP240801a: GMG observation
  21. EP240801a: TRT optical counterpart detection
  22. EP240801a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  23. GRB 240801B: AstroSat CZTI detection of a bright long burst
  24. Fermi GRB 240801A: Global MASTER-Net observations report
  25. GRB 240801A: Fermi GBM Final Real-time Localization
  26. GRB 240730C: AstroSat CZTI detection of a long burst
  27. GRB 240731A: Fermi GBM Final Localization
  28. Fermi trigger No 744128417: Global MASTER-Net observations report
  29. Fermi trigger No 744083370: Global MASTER-Net observations report
  30. GRB 240731A: AstroSat CZTI detection
  31. GRB 240730A: Osservatorio Astronomico Nastro Verde upper limit
  32. GRB240730A: BOOTES-5/JGT early optical upper limit
  33. Fermi Gamma-ray Burst Monitor trigger 744061103/240730818 is not a GRB
  34. Fermi GRB 240730B: Global MASTER-Net observations report
  35. GRB 240730B: Fermi GBM Final Real-time Localization
  36. Swift GRB 240730A: Global MASTER-Net observations report
  37. GRB 240730A: Swift-XRT refined Analysis
  38. GRB 240715A: Swift-XRT afterglow detection
  39. GRB 240730A: KAIT Optical Upper Limit
  40. GRB 240727C: GRBAlpha detection
  41. GRB 240730A: Swift/UVOT Upper Limits
  42. GRB 240730A: Enhanced Swift-XRT position
  43. GRB 240730A: Swift detection of a burst
  44. Fermi trigger No 743953682: Global MASTER-Net observations report
  45. GRB 240727A: Swift-BAT refined analysis
  46. Fermi Gamma-ray Burst Monitor trigger 743953682/240729575 is not a GRB
  47. LIGO/Virgo/KAGRA S240615dg: GRAWITA wide-field optical observations
  48. GRB 240727A: observations of optical counterpart.
  49. GRB 240727B: Swift-XRT observations
  50. Fermi GRB 240727A: Global MASTER-Net observations report
  51. GRB 240727A: Swift/UVOT detection
  52. Fermi trigger No 743868421: Global MASTER-Net observations report
  53. Fermi Gamma-ray Burst Monitor trigger 743868421/240728588 is not a GRB
  54. GRB 240727A: Osservatorio Astronomico Nastro Verde upper limit
  55. EP-WXT trigger 01709002661 is not a real source
  56. GRB 240727A: NOT optical observation
  57. GRB 240727A: JinShan optical upper limits
  58. GRB 240727A Bassano Bresciano Observatory upper limit
  59. GRB 240727D: Correction to the GRB name in GCN 36958
  60. GRB 240727A: Fermi GBM Final Real-time Localization
  61. GRB 240727C: AstroSat CZTI detection of a long burst
  62. GRB 240727A: Swift-XRT refined Analysis
  63. GRB 240720B: GRBAlpha detection
  64. GRB 240718A: GRBAlpha detection
  65. GRB 240710B: GRBAlpha detection
  66. GRB 240627A: GRBAlpha detection
  67. Fermi GRB 240726A: Global MASTER-Net observations report
  68. GRB 240727A: Enhanced Swift-XRT position
  69. GRB 240727B: Fermi GBM Observation
  70. Swift GRB240727.16: Global MASTER-Net observations report
  71. GRB240529A: VIRT optical transient detection
  72. GRB 240727B: Swift ToO observations
  73. GRB 240727B: Swift/BAT-GUANO arcminute localization of a long burst
  74. GRB 240726A: SVOM/GRM observation
  75. GRB 240727B: AstroSat CZTI detection
  76. GRB 240726B: AstroSat CZTI detection of a short burst
  77. GRB240727A: Skynet Optical Afterglow Observations
  78. GRB 240727A: TRT optical afterglow detection
  79. GRB 240727A: KAIT Optical Afterglow Candidate
  80. GRB 240727A: Swift detection of a burst
  81. GRB 240726A: AstroSat CZTI detection of a short burst
  82. IceCube-240725A: Upper limits from a search for additional neutrino events in IceCube
  83. GRB 240726A: Fermi GBM Final Real-time Localization
  84. Fermi-LAT gamma-ray observations of IceCube-240725A
  85. IceCube Alert 240725.22: Global MASTER-Net observations report
  86. IceCube-240725A - IceCube observation of a high-energy neutrino candidate track-like event
  87. Swift Trigger 1244778 is not a GRB
  88. Swift GRB240725.11: Global MASTER-Net observations report
  89. IceCube-240721A: Two candidates from the Zwicky Transient Facility
  90. GRB 240720A: Swift-BAT refined analysis
  91. IceCube-240721A: Upper limits from a search for additional neutrino events in IceCube
  92. Fermi trigger No 743418632: Global MASTER-Net observations report
  93. Fermi trigger No 743315411: Global MASTER-Net observations report
  94. LIGO/Virgo/KAGRA S240716b: Upper limits from Swift/BAT-GUANO
  95. LIGO/Virgo/KAGRA S240703ad: Upper limits from Swift/BAT-GUANO
  96. Fermi trigger No 743345551: Global MASTER-Net observations report
  97. Fermi-LAT gamma-ray observations of IceCube-240721A
  98. Fermi Gamma-ray Burst Monitor trigger 743271526/240721680 is not a GRB
  99. Fermi trigger No 743219692: Global MASTER-Net observations report
  100. IceCube-240721A - IceCube observation of a high-energy neutrino candidate track-like event

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