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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

11535 results found.

  1. IceCube-240808A - IceCube observation of a high-energy neutrino candidate track-like event
  2. GRB 240801A: GRBAlpha detection
  3. GRB 240807B: Fermi GBM Final Localization
  4. GRB 240710B: VZLUSAT-2 detection
  5. GRB 240805A: ATCA Radio Upper Limits
  6. Fermi trigger No 744761058: Global MASTER-Net observations report
  7. EP240807a/GRB 240807A: EP-FXT detection of the X-ray emission
  8. GRB 240710A: VZLUSAT-2 detection
  9. GRB 240807A: Fermi GBM Final Localization
  10. Fermi trigger No 744629911: Global MASTER-Net observations report
  11. Konus-Wind detection of GRB 240805A
  12. GRB240805A: Fermi GBM Observation
  13. Fermi Gamma-ray Burst Monitor trigger 240806402/744629911 is not a GRB
  14. GRB 240624B: VZLUSAT-2 detection
  15. GRB 240619C: VZLUSAT-2 detection
  16. Fermi trigger No 744544656: Global MASTER-Net observations report
  17. GRB 240805A: SVOM/GRM observation
  18. Fermi GRB 240805A: Global MASTER-Net observations report
  19. Fermi Gamma-ray Burst Monitor trigger 744558410/240805574 is not a GRB
  20. GRB 240805A: Fermi-LAT detection
  21. GRB 240805A: INTEGRAL spectral analysis
  22. GRB 240805A: A long GRB detected by INTEGRAL
  23. GRB 240805A: Fermi GBM Final Real-time Localization
  24. Fermi GRB 240804A: Global MASTER-Net observations report
  25. GRB 240804A: Fermi GBM Final Real-time Localization
  26. Fermi trigger No 744459130: Global MASTER-Net observations report
  27. Fermi Gamma-ray Burst Monitor trigger 744459130/240804425 is not a GRB
  28. Fermi trigger No 744278264: Global MASTER-Net observations report
  29. GRB 240801B: AstroSat CZTI Updated classification - likely a solar flare
  30. Fermi GBM trigger 744179961 / 240801194 can not be confirmed as a GRB
  31. Fermi trigger No 744204856: Global MASTER-Net observations report
  32. GRB 240801B: AstroSat CZTI detection of a bright long burst
  33. Fermi GRB 240801A: Global MASTER-Net observations report
  34. GRB 240801A: Fermi GBM Final Real-time Localization
  35. GRB 240731A: Fermi GBM Final Localization
  36. Fermi trigger No 744128417: Global MASTER-Net observations report
  37. Fermi trigger No 744083370: Global MASTER-Net observations report
  38. GRB 240731A: AstroSat CZTI detection
  39. Fermi Gamma-ray Burst Monitor trigger 744061103/240730818 is not a GRB
  40. Fermi GRB 240730B: Global MASTER-Net observations report
  41. GRB 240730B: Fermi GBM Final Real-time Localization
  42. Fermi trigger No 743953682: Global MASTER-Net observations report
  43. Fermi Gamma-ray Burst Monitor trigger 743953682/240729575 is not a GRB
  44. GRB 240727B: Swift-XRT observations
  45. Fermi GRB 240727A: Global MASTER-Net observations report
  46. Fermi trigger No 743868421: Global MASTER-Net observations report
  47. Fermi Gamma-ray Burst Monitor trigger 743868421/240728588 is not a GRB
  48. GRB 240727D: Correction to the GRB name in GCN 36958
  49. GRB 240727A: Fermi GBM Final Real-time Localization
  50. GRB 240718A: GRBAlpha detection
  51. GRB 240710B: GRBAlpha detection
  52. Fermi GRB 240726A: Global MASTER-Net observations report
  53. GRB 240727B: Fermi GBM Observation
  54. GRB 240727B: Swift ToO observations
  55. GRB 240727B: Swift/BAT-GUANO arcminute localization of a long burst
  56. GRB 240726A: SVOM/GRM observation
  57. GRB 240727B: AstroSat CZTI detection
  58. GRB 240726A: AstroSat CZTI detection of a short burst
  59. GRB 240726A: Fermi GBM Final Real-time Localization
  60. Fermi-LAT gamma-ray observations of IceCube-240725A
  61. IceCube-240725A - IceCube observation of a high-energy neutrino candidate track-like event
  62. Fermi trigger No 743418632: Global MASTER-Net observations report
  63. Fermi trigger No 743315411: Global MASTER-Net observations report
  64. Fermi trigger No 743345551: Global MASTER-Net observations report
  65. Fermi-LAT gamma-ray observations of IceCube-240721A
  66. Fermi Gamma-ray Burst Monitor trigger 743271526/240721680 is not a GRB
  67. Fermi trigger No 743219692: Global MASTER-Net observations report
  68. IceCube-240721A - IceCube observation of a high-energy neutrino candidate track-like event
  69. Fermi Gamma-ray Burst Monitor trigger 743243582/240721356 (GRB 240721A) is not a GRB
  70. GRB 240721A: Fermi GBM Final Real-time Localization
  71. Fermi GRB 240720A: Global MASTER-Net observations report
  72. GRB 240720A: AstroSat CZTI detection
  73. GRB 240720A: Fermi GBM observation
  74. Konus-Wind detection of GRB 240718A
  75. GRB 240713A: SVOM/GRM observation
  76. Fermi GRB 240718A: Global MASTER-Net observations report
  77. GRB 240718A: Fermi GBM Observation
  78. GRB 240718A: Fermi-LAT Detection
  79. GRB 240718A: SVOM/GRM observation
  80. GRB 240718A: BALROG localization (Fermi Trigger 742976945 / GRB 240718270)
  81. GRB 240718A: Fermi GBM Final Real-time Localization
  82. Fermi-LAT gamma-ray observations of IceCube-cascade-240714A
  83. GRB 240715A: Swift/UVOT observations of the XRT sources.
  84. GRB 240715A: GECAM-C detection of a short burst
  85. Konus-Wind detection of GRB 240715A
  86. GRB 240715A: TRT optical upper limit on one Swift/XRT candidate
  87. SVOM/GRM In-Flight Trigger of GRB 240715A
  88. GRB 240713A: LAST optical upper limit
  89. Fermi GRB 240715A: Global MASTER-Net observations report
  90. GRB 240713A: optical upper limits from the INAF Asiago Observatory
  91. GRB 240715A: Fermi GBM Observation
  92. GRB240715A: GRANDMA Optical Upper Limits
  93. IPN triangulation of GRB 240715A (short)
  94. GRB 240715A: Fermi GBM Final Real-time Localization
  95. GRB 240713A: J-band upper limit from WINTER
  96. GRB 240713A: NOT optical upper limits on three EP/FXT candidates
  97. GRB 240713A: JinShan optical upper limits
  98. GRB 240713A: OHP/T120 optical upper limit
  99. GRB240713A: X-ray follow-up observation with EP-FXT
  100. Fermi Sub-threshold Observation of GRB240713A

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