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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"

27259 results found.

  1. Fermi GRB 240805A: Global MASTER-Net observations report
  2. Swift GRB 240805A: Global MASTER-Net observations report
  3. Fermi Gamma-ray Burst Monitor trigger 744558410/240805574 is not a GRB
  4. GRB 240805A: Swift-XRT refined Analysis
  5. GRB 240805B: Swift detection of a burst
  6. GRB 240805A: Fermi-LAT detection
  7. EP240804a: VLT/X-shooter spectroscopic redshift
  8. EP240804a: LCOGT optical counterpart detection
  9. EP-WXT trigger 00109017646 is not a real source
  10. EP240804a: NOT optical counterpart detection
  11. EP240804a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  12. EP240802a: correction of EP-WXT trigger time in GCN 37019
  13. GRB 240805A: Swift detection of a burst
  14. GRB 240805A: Fermi GBM Final Real-time Localization
  15. Fermi GRB 240804A: Global MASTER-Net observations report
  16. GRB 240804A: Fermi GBM Final Real-time Localization
  17. Fermi trigger No 744459130: Global MASTER-Net observations report
  18. Fermi Gamma-ray Burst Monitor trigger 744459130/240804425 is not a GRB
  19. EP240802A: Bassano Bresciano Observatory upper limit
  20. GRB 240802A: SVOM/GRM observation
  21. EP240802a: Time coincidence with GRB 240802A and optical upper limits with Kinder observations
  22. Fermi trigger No 744278264: Global MASTER-Net observations report
  23. EP240802a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  24. GRB 240802A: AstroSat CZTI detection of a long burst
  25. EP240801a: optical observations at CrAO and AbAO
  26. EP240801a: GRANDMA and Kilonova-Catcher optical observations
  27. EP240801a: Leavitt Observatory optical observations
  28. EP240801a: GTC spectroscopy and absorption redshift
  29. GRB 240801B: AstroSat CZTI Updated classification - likely a solar flare
  30. EP240801a: JinShan optical observations
  31. GRB 240727C: SVOM/GRM observation
  32. EP240801a: NOT optical observations
  33. EP240801a: follow-up observation with LCOGT
  34. Fermi GBM trigger 744179961 / 240801194 can not be confirmed as a GRB
  35. GRB 240730A: Swift-BAT refined analysis
  36. EP240801a: GSP follow-up observations of the candidate counterpart
  37. Fermi trigger No 744204856: Global MASTER-Net observations report
  38. EP240801a: Kinder follow-up observations of the candidate counterpart
  39. EP240801a: KAIT optical counterpart observations
  40. EP240801a: GMG observation
  41. EP240801a: TRT optical counterpart detection
  42. EP240801a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  43. GRB 240801B: AstroSat CZTI detection of a bright long burst
  44. Fermi GRB 240801A: Global MASTER-Net observations report
  45. GRB 240801A: Fermi GBM Final Real-time Localization
  46. GRB 240731A: Fermi GBM Final Localization
  47. Fermi trigger No 744128417: Global MASTER-Net observations report
  48. Fermi trigger No 744083370: Global MASTER-Net observations report
  49. GRB 240731A: AstroSat CZTI detection
  50. GRB 240730A: Osservatorio Astronomico Nastro Verde upper limit
  51. GRB240730A: BOOTES-5/JGT early optical upper limit
  52. Fermi Gamma-ray Burst Monitor trigger 744061103/240730818 is not a GRB
  53. Fermi GRB 240730B: Global MASTER-Net observations report
  54. GRB 240730B: Fermi GBM Final Real-time Localization
  55. Swift GRB 240730A: Global MASTER-Net observations report
  56. GRB 240730A: Swift-XRT refined Analysis
  57. GRB 240727C: GRBAlpha detection
  58. GRB 240730A: Swift/UVOT Upper Limits
  59. GRB 240730A: Swift detection of a burst
  60. Fermi trigger No 743953682: Global MASTER-Net observations report
  61. GRB 240727A: Swift-BAT refined analysis
  62. Fermi Gamma-ray Burst Monitor trigger 743953682/240729575 is not a GRB
  63. LIGO/Virgo/KAGRA S240615dg: GRAWITA wide-field optical observations
  64. GRB 240727A: observations of optical counterpart.
  65. Fermi GRB 240727A: Global MASTER-Net observations report
  66. GRB 240727A: Swift/UVOT detection
  67. Fermi trigger No 743868421: Global MASTER-Net observations report
  68. Fermi Gamma-ray Burst Monitor trigger 743868421/240728588 is not a GRB
  69. GRB 240727A: Osservatorio Astronomico Nastro Verde upper limit
  70. EP-WXT trigger 01709002661 is not a real source
  71. GRB 240727A Bassano Bresciano Observatory upper limit
  72. GRB 240727D: Correction to the GRB name in GCN 36958
  73. GRB 240727A: Fermi GBM Final Real-time Localization
  74. GRB 240727C: AstroSat CZTI detection of a long burst
  75. GRB 240727A: Swift-XRT refined Analysis
  76. GRB 240720B: GRBAlpha detection
  77. GRB 240718A: GRBAlpha detection
  78. GRB 240710B: GRBAlpha detection
  79. Fermi GRB 240726A: Global MASTER-Net observations report
  80. GRB 240727B: Fermi GBM Observation
  81. Swift GRB240727.16: Global MASTER-Net observations report
  82. GRB 240727B: Swift/BAT-GUANO arcminute localization of a long burst
  83. GRB 240726A: SVOM/GRM observation
  84. GRB 240727B: AstroSat CZTI detection
  85. GRB240727A: Skynet Optical Afterglow Observations
  86. GRB 240727A: Swift detection of a burst
  87. GRB 240726A: Fermi GBM Final Real-time Localization
  88. IceCube Alert 240725.22: Global MASTER-Net observations report
  89. Swift Trigger 1244778 is not a GRB
  90. Swift GRB240725.11: Global MASTER-Net observations report
  91. GRB 240720A: Swift-BAT refined analysis
  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 Gamma-ray Burst Monitor trigger 743271526/240721680 is not a GRB
  98. Fermi trigger No 743219692: Global MASTER-Net observations report
  99. IceCube Alert 240721.68: Global MASTER-Net observations report
  100. Fermi Gamma-ray Burst Monitor trigger 743243582/240721356 (GRB 240721A) is not a GRB

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