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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"

27227 results found.

  1. GRB 161022A: LT observations
  2. GRB 161022A: TAROT Calern observatory optical observations
  3. GRB 161022A: Swift detection of a burst
  4. GRB 161020A: A long GRB detected by INTEGRAL
  5. Konus-Wind observation of GRB 161017A
  6. GRB 161017A: Swift-BAT refined analysis
  7. GRB 161017A: Lomonosov Gamma Ray and MASTER Optical prompt observations
  8. GRB 161017A: Swift/UVOT Detection
  9. GRB 161017A: Swift-XRT refined Analysis
  10. GRB 161017A: Fermi GBM observation
  11. GRB 161014A: Continued RATIR Optical and NIR Observations
  12. GRB 161015A: Swift/UVOT observations
  13. GRB 161017A: Swift detection of a burst with a bright optical afterglow
  14. GRB161017.74 MASTER-Net OT detection
  15. GRB 161014A: VLT/X-shooter redshift confirmation
  16. GRB161015A: AstroSat CZTI detection
  17. GRB 161015A: Fermi GBM detection
  18. GRB 161015A: Fermi-LAT detection
  19. GRB161004A: Further analysis of the burst nature
  20. GRB 161014A: RATIR Optical and NIR Observations
  21. GRB 161014A: Fermi GBM observation
  22. GRB 161014A: Swift-XRT refined Analysis
  23. GRB 161014A: Swift-BAT refined analysis
  24. GRB 161014A: AROMA-N Optical Observation
  25. GRB 161014A: Swift/UVOT Detection
  26. GRB161014A: NOT optical observations
  27. GRB 161011A: RATIR Optical and NIR Observations
  28. GRB 161014A: Swift-XRT and UVOT afterglow detection
  29. GRB 161014A : Xinglong TNT optical observation
  30. GRB161014A: optical afterglow candidate with the LCOGT-FTS
  31. GRB 161014A: Swift detection of a burst
  32. GRB 161010A: Swift/UVOT Possible Detection
  33. GRB 161010A: CALET Gamma-Ray Burst Monitor detection
  34. GRB 161011A, Swift-BAT refined analysis
  35. GRB 161011A: Swift/UVOT Upper Limits
  36. GRB 161011A: Swift-XRT refined Analysis
  37. GRB 161011A: Swift detection of a burst
  38. GRB 161007A: NOT optical observations
  39. GRB 161007A: Swift-BAT refined analysis
  40. GRB 161007A: Swift/UVOT Upper Limits
  41. GRB 161007A: Swift-XRT refined Analysis
  42. GRB 161007A: GTC observations
  43. GRB 161007A: MASTER-net early optical observations
  44. GRB 161007A: Swift detection of a burst
  45. GRB 160821A: Maisoncelles observatory optical observations
  46. GRB 160925A: Kottamia R-band observation
  47. Konus-Wind observation of GRB 161004B
  48. GRB 161004B: CALET Gamma-Ray Burst Monitor detection
  49. GRB 160927A: CALET Gamma-Ray Burst Monitor ground detection
  50. GRB 161004A: Swift-BAT refined analysis
  51. GRB 161004B: Fermi GBM detection
  52. GRB 161004B: Swift/UVOT Upper Limits
  53. GRB161004B: AstroSat CZTI detection
  54. GRB 161004B: Swift-BAT refined analysis
  55. GRB 161004B: Swift-XRT refined Analysis
  56. GRB 161004A: RATIR Optical and NIR Observations
  57. GRB 160917B: Lomonosov BDRG gamma ray discovery
  58. GRB 160917A: Lomonosov BDRG gamma ray detection
  59. GRB 160915A: Lomonosov BDRG gamma ray detection
  60. GRB 161004B: Swift detection of a burst
  61. GRB 161004A: Swift-XRT refined Analysis
  62. GRB 161004A: Swift/UVOT Detection
  63. Swift Trigger 715209 is not an astrophysical event
  64. GRB 161004A: Bassano Bresciano Observatory upper limit
  65. GRB 161004A: Swift detection of a burst with a possible optical counterpart
  66. GRB 161001A: MASTER-OAFA and MASTER-SAAO early optical observations
  67. GRB 161001A: GROND afterglow candidate
  68. GRB 161001A, Swift-BAT refined analysis (likely a short GRB)
  69. GRB 161001A: Fermi GBM detection
  70. GRB 161001A: Swift-XRT refined Analysis
  71. GRB 161001A: Swift/UVOT Upper Limits
  72. GRB 161001A: Swift detection of a burst
  73. Fermi GBM trigger 496791348/160928900 is not a GRB
  74. GRB 160927A: Swift/UVOT Upper Limits
  75. GRB 160927A: Bassano Bresciano Observatory optical upper limit
  76. GRB 160927A: Swift-BAT refined analysis
  77. GRB 160927A: NOT optical observations
  78. GRB 160927A: GROND Observations
  79. GRB 160927A: Swift-XRT refined Analysis
  80. GRB160927A: D50 optical limit
  81. GRB 160927A: Swift detection of a short hard burst
  82. GRB160910A: AstroSat CZTI detection
  83. GRB 160925A/MASTER optical transient: Mondy optical observations
  84. GRB 160925A: Bassano Bresciano Photometry of MASTER optical transient
  85. GRB 160925A: Optical spectroscopy of MASTER optical transient
  86. GRB160824B: AstroSat CZTI detection
  87. GRB160917A: AstroSat CZTI detection
  88. GRB 160925A / Fermi 496473540: MASTER OT observations
  89. GRB 160925A / Fermi 496473540: Global MASTER Net OT discovery
  90. GRB 160917A: Swift-BAT refined analysis
  91. GRB 160917A: RATIR Optical and NIR Observations
  92. GRB 160917A: Fermi GBM observation
  93. GRB 160917A: Swift/UVOT Detection
  94. GRB 160917A: Swift-XRT refined Analysis
  95. GRB 160917A: Swift detection of a burst
  96. GRB 160912A, Swift-BAT refined analysis
  97. GRB 160912A: RATIR Optical and NIR Observations
  98. GRB 160912A: Swift/UVOT Weak Afterglow Detection
  99. GRB 160912A Liverpool Telescope optical afterglow
  100. GRB 160912A: Swift-XRT refined Analysis

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