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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"

45502 results found.

  1. EP-WXT trigger 00109017646 is not a real source
  2. EP240804a: NOT optical counterpart detection
  3. EP240804a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  4. EP240802a: correction of EP-WXT trigger time in GCN 37019
  5. GRB 240805A: Swift detection of a burst
  6. GRB 240805A: Fermi GBM Final Real-time Localization
  7. Fermi GRB 240804A: Global MASTER-Net observations report
  8. EP240802a: Montarrenti Observatory optical upper limit
  9. GRB 240804A: Fermi GBM Final Real-time Localization
  10. Fermi trigger No 744459130: Global MASTER-Net observations report
  11. IPN triangulation of GRB 240802A / EP 240802a
  12. Fermi Gamma-ray Burst Monitor trigger 744459130/240804425 is not a GRB
  13. EP240801a: Osservatorio Astronomico Nastro Verde upper limit
  14. EP240802A: Bassano Bresciano Observatory upper limit
  15. GRB 240802A: SVOM/GRM observation
  16. EP240802a: Time coincidence with GRB 240802A and optical upper limits with Kinder observations
  17. Fermi trigger No 744278264: Global MASTER-Net observations report
  18. EP240802a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  19. GRB 240802A: AstroSat CZTI detection of a long burst
  20. EP240801a: further SAO RAS optical observations
  21. EP240801a: optical observations at CrAO and AbAO
  22. EP240801a: GRANDMA and Kilonova-Catcher optical observations
  23. EP240801a: Leavitt Observatory optical observations
  24. EP240801a: GTC spectroscopy and absorption redshift
  25. EP240801a: SAO RAS optical observations
  26. GRB 240801B: AstroSat CZTI Updated classification - likely a solar flare
  27. EP240801a: JinShan optical observations
  28. GRB 240727C: SVOM/GRM observation
  29. EP240801a: NOT optical observations
  30. EP240801a: follow-up observation with LCOGT
  31. Fermi GBM trigger 744179961 / 240801194 can not be confirmed as a GRB
  32. GRB 240730A: Swift-BAT refined analysis
  33. EP240801a: GSP follow-up observations of the candidate counterpart
  34. Fermi trigger No 744204856: Global MASTER-Net observations report
  35. EP240801a: Kinder follow-up observations of the candidate counterpart
  36. EP240708a: Kinder follow-up observations of the candidate counterpart (duplicate submission of GCN 37002)
  37. EP240801a: KAIT optical counterpart observations
  38. EP240801a: GMG observation
  39. EP240801a: TRT optical counterpart detection
  40. EP240801a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  41. GRB 240801B: AstroSat CZTI detection of a bright long burst
  42. Fermi GRB 240801A: Global MASTER-Net observations report
  43. GRB 240801A: Fermi GBM Final Real-time Localization
  44. GRB 240730C: AstroSat CZTI detection of a long burst
  45. GRB 240731A: Fermi GBM Final Localization
  46. Fermi trigger No 744128417: Global MASTER-Net observations report
  47. Fermi trigger No 744083370: Global MASTER-Net observations report
  48. GRB 240731A: AstroSat CZTI detection
  49. GRB 240730A: Osservatorio Astronomico Nastro Verde upper limit
  50. GRB240730A: BOOTES-5/JGT early optical upper limit
  51. Fermi Gamma-ray Burst Monitor trigger 744061103/240730818 is not a GRB
  52. Fermi GRB 240730B: Global MASTER-Net observations report
  53. GRB 240730B: Fermi GBM Final Real-time Localization
  54. Swift GRB 240730A: Global MASTER-Net observations report
  55. GRB 240730A: Swift-XRT refined Analysis
  56. GRB 240715A: Swift-XRT afterglow detection
  57. GRB 240730A: KAIT Optical Upper Limit
  58. GRB 240727C: GRBAlpha detection
  59. GRB 240730A: Swift/UVOT Upper Limits
  60. GRB 240730A: Enhanced Swift-XRT position
  61. GRB 240730A: Swift detection of a burst
  62. Fermi trigger No 743953682: Global MASTER-Net observations report
  63. GRB 240727A: Swift-BAT refined analysis
  64. Fermi Gamma-ray Burst Monitor trigger 743953682/240729575 is not a GRB
  65. LIGO/Virgo/KAGRA S240615dg: GRAWITA wide-field optical observations
  66. GRB 240727A: observations of optical counterpart.
  67. GRB 240727B: Swift-XRT observations
  68. Fermi GRB 240727A: Global MASTER-Net observations report
  69. GRB 240727A: Swift/UVOT detection
  70. Fermi trigger No 743868421: Global MASTER-Net observations report
  71. Fermi Gamma-ray Burst Monitor trigger 743868421/240728588 is not a GRB
  72. GRB 240727A: Osservatorio Astronomico Nastro Verde upper limit
  73. EP-WXT trigger 01709002661 is not a real source
  74. GRB 240727A: NOT optical observation
  75. GRB 240727A: JinShan optical upper limits
  76. GRB 240727A Bassano Bresciano Observatory upper limit
  77. GRB 240727D: Correction to the GRB name in GCN 36958
  78. GRB 240727A: Fermi GBM Final Real-time Localization
  79. GRB 240727C: AstroSat CZTI detection of a long burst
  80. GRB 240727A: Swift-XRT refined Analysis
  81. GRB 240720B: GRBAlpha detection
  82. GRB 240718A: GRBAlpha detection
  83. GRB 240710B: GRBAlpha detection
  84. GRB 240627A: GRBAlpha detection
  85. Fermi GRB 240726A: Global MASTER-Net observations report
  86. GRB 240727A: Enhanced Swift-XRT position
  87. GRB 240727B: Fermi GBM Observation
  88. Swift GRB240727.16: Global MASTER-Net observations report
  89. GRB240529A: VIRT optical transient detection
  90. GRB 240727B: Swift ToO observations
  91. GRB 240727B: Swift/BAT-GUANO arcminute localization of a long burst
  92. GRB 240726A: SVOM/GRM observation
  93. GRB 240727B: AstroSat CZTI detection
  94. GRB 240726B: AstroSat CZTI detection of a short burst
  95. GRB240727A: Skynet Optical Afterglow Observations
  96. GRB 240727A: TRT optical afterglow detection
  97. GRB 240727A: KAIT Optical Afterglow Candidate
  98. GRB 240727A: Swift detection of a burst
  99. GRB 240726A: AstroSat CZTI detection of a short burst
  100. IceCube-240725A: Upper limits from a search for additional neutrino events in IceCube

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