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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"

37346 results found.

  1. GRB 240805B: Swift detection of a burst
  2. GRB 240805A: Fermi-LAT detection
  3. GRB 240805A: INTEGRAL spectral analysis
  4. EP240801a: Continued optical observations at ZTSh (CraO)
  5. GRB 240805A: A long GRB detected by INTEGRAL
  6. GRB 240805A: Swift detection of a burst
  7. GRB 240805A: Fermi GBM Final Real-time Localization
  8. Fermi GRB 240804A: Global MASTER-Net observations report
  9. EP240802a: Montarrenti Observatory optical upper limit
  10. GRB 240804A: Fermi GBM Final Real-time Localization
  11. IPN triangulation of GRB 240802A / EP 240802a
  12. Fermi Gamma-ray Burst Monitor trigger 744459130/240804425 is not a GRB
  13. EP240802A: Bassano Bresciano Observatory upper limit
  14. GRB 240802A: SVOM/GRM observation
  15. EP240802a: Time coincidence with GRB 240802A and optical upper limits with Kinder observations
  16. GRB 240802A: AstroSat CZTI detection of a long burst
  17. EP240801a: further SAO RAS optical observations
  18. EP240801a: optical observations at CrAO and AbAO
  19. EP240801a: Leavitt Observatory optical observations
  20. EP240801a: SAO RAS optical observations
  21. GRB 240801B: AstroSat CZTI Updated classification - likely a solar flare
  22. GRB 240727C: SVOM/GRM observation
  23. Fermi GBM trigger 744179961 / 240801194 can not be confirmed as a GRB
  24. GRB 240730A: Swift-BAT refined analysis
  25. EP240801a: Kinder follow-up observations of the candidate counterpart
  26. EP240801a: KAIT optical counterpart observations
  27. GRB 240801B: AstroSat CZTI detection of a bright long burst
  28. Fermi GRB 240801A: Global MASTER-Net observations report
  29. GRB 240801A: Fermi GBM Final Real-time Localization
  30. GRB 240730C: AstroSat CZTI detection of a long burst
  31. GRB 240731A: Fermi GBM Final Localization
  32. GRB 240731A: AstroSat CZTI detection
  33. GRB 240730A: Osservatorio Astronomico Nastro Verde upper limit
  34. GRB240730A: BOOTES-5/JGT early optical upper limit
  35. Fermi Gamma-ray Burst Monitor trigger 744061103/240730818 is not a GRB
  36. Fermi GRB 240730B: Global MASTER-Net observations report
  37. GRB 240730B: Fermi GBM Final Real-time Localization
  38. Swift GRB 240730A: Global MASTER-Net observations report
  39. GRB 240730A: Swift-XRT refined Analysis
  40. GRB 240715A: Swift-XRT afterglow detection
  41. GRB 240730A: KAIT Optical Upper Limit
  42. GRB 240727C: GRBAlpha detection
  43. GRB 240730A: Swift/UVOT Upper Limits
  44. GRB 240730A: Enhanced Swift-XRT position
  45. GRB 240730A: Swift detection of a burst
  46. GRB 240727A: Swift-BAT refined analysis
  47. Fermi Gamma-ray Burst Monitor trigger 743953682/240729575 is not a GRB
  48. LIGO/Virgo/KAGRA S240615dg: GRAWITA wide-field optical observations
  49. GRB 240727A: observations of optical counterpart.
  50. GRB 240727B: Swift-XRT observations
  51. Fermi GRB 240727A: Global MASTER-Net observations report
  52. GRB 240727A: Swift/UVOT detection
  53. Fermi Gamma-ray Burst Monitor trigger 743868421/240728588 is not a GRB
  54. GRB 240727A: Correction to time in GCN36960
  55. GRB 240727A: Osservatorio Astronomico Nastro Verde upper limit
  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. GRB 240727B: Swift ToO observations
  71. GRB 240727B: Swift/BAT-GUANO arcminute localization of a long burst
  72. GRB 240726A: SVOM/GRM observation
  73. GRB 240727B: AstroSat CZTI detection
  74. GRB 240726B: AstroSat CZTI detection of a short burst
  75. GRB240727A: Skynet Optical Afterglow Observations
  76. GRB 240727A: TRT optical afterglow detection
  77. GRB 240727A: KAIT Optical Afterglow Candidate
  78. GRB 240727A: Swift detection of a burst
  79. GRB 240726A: AstroSat CZTI detection of a short burst
  80. GRB 240726A: Fermi GBM Final Real-time Localization
  81. Swift Trigger 1244778 is not a GRB
  82. IceCube-240721A: Two candidates from the Zwicky Transient Facility
  83. GRB 240720A: Swift-BAT refined analysis
  84. LIGO/Virgo/KAGRA S240716b: Upper limits from Swift/BAT-GUANO
  85. LIGO/Virgo/KAGRA S240703ad: Upper limits from Swift/BAT-GUANO
  86. Fermi Gamma-ray Burst Monitor trigger 743271526/240721680 is not a GRB
  87. Fermi Gamma-ray Burst Monitor trigger 743243582/240721356 (GRB 240721A) is not a GRB
  88. GRB 240720B: SVOM/GRM observation
  89. GRB 240721A: Fermi GBM Final Real-time Localization
  90. GRB 240720B: AstroSat CZTI detection of a short burst
  91. Fermi GRB 240720A: Global MASTER-Net observations report
  92. GRB 240720A: AstroSat CZTI detection
  93. GRB 240720A: Fermi GBM observation
  94. GRB 240720A: Swift detection of a burst
  95. Konus-Wind detection of GRB 240718A
  96. GRB 240713A: SVOM/GRM observation
  97. Fermi GRB 240718A: Global MASTER-Net observations report
  98. GRB 240718A: Fermi GBM Observation
  99. GRB 240718A: Fermi-LAT Detection
  100. GRB 240718A: SVOM/GRM observation

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