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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').

17519 results found.

  1. GRB 240819A: TRT optical upper limits on the Swift/XRT and EP/FXT sources
  2. GRB 240819A: Swift ToO observations
  3. GRB GRB 240809A: Osservatorio Astronomico "Nastro Verde" optical observations: detection of an optical counterpart
  4. GRB 240805B: Osservatorio Astronomico Nastro Verde upper limit
  5. EP240802a: Kinder optical, SWIFT-UVOT, and SWIFT-XRT upper limits 6 days after the WXT detection
  6. Konus-Wind detection of GRB 240811A
  7. GRB 240811A: Swift-BAT refined analysis
  8. GRB 240809A: Swift-BAT refined analysis
  9. GRB 240811A: Bassano Bresciano Observatory upper limit
  10. GRB 240811A: Swift-XRT refined Analysis
  11. GRB 240811A: Swift/UVOT Upper Limits
  12. GRB 240811A: LCOGT Optical Upper Limit
  13. GRB 240811A: Enhanced Swift-XRT position
  14. Konus-Wind detection of GRB 240809A
  15. Swift GRB 240811A: Global MASTER-Net observations report
  16. GRB 240811A: Swift detection of a burst
  17. GRB 240809A: Bassano Bresciano Observatory optical observations
  18. GRB 240809A: KAIT optical observations
  19. GRB 240809A: GIT afterglow observations
  20. GRB 240809A: Swift/UVOT Detection
  21. GRB 240809A: Swift-XRT refined Analysis
  22. IPN triangulation of GRB 240807A / EP 240807a
  23. Swift GRB 240809A: Global MASTER-Net observations report
  24. GRB 240809A: JinShan optical observations
  25. GRB 240809A: Enhanced Swift-XRT position
  26. GRB 240809A: Skynet & Photon Ranch Optical Afterglow Observations
  27. GRB 240809A: SVOM/GRM observation
  28. GRB 240809A: Swift detection of a burst with a bright optical counterpart
  29. GRB 240805A: ATCA Radio Upper Limits
  30. GRB 240805B: GIT optical upper limit
  31. GRB 240805B: Swift-BAT refined analysis
  32. GRB 240805A: Swift-BAT refined analysis
  33. Konus-Wind detection of GRB 240805A
  34. GRB 240805B Bassano Bresciano Observatory upper limit
  35. GRB240805A: Fermi GBM Observation
  36. GRB 240805B: JinShan optical afterglow detection
  37. GRB 240805B: AbAO, CrAO, and Terskol optical upper limits
  38. GRB 240805B: Swift-XRT refined Analysis
  39. GRB 240805B: Swift/UVOT Upper Limits
  40. GRB 240805A: Swift/UVOT Upper Limits
  41. GRB 240805A: SVOM/GRM observation
  42. GRB 240805B: Enhanced Swift-XRT position
  43. GRB 240805B: LCOGT Optical Upper Limits
  44. Swift GRB 240805B: Global MASTER-Net observations report
  45. GRB 240805B: JinShan optical upper limits
  46. Swift GRB 240805A: Global MASTER-Net observations report
  47. GRB 240805A: Swift-XRT refined Analysis
  48. GRB 240805B: Swift detection of a burst
  49. GRB 240805A: Fermi-LAT detection
  50. GRB 240805A: INTEGRAL spectral analysis
  51. GRB 240805A: A long GRB detected by INTEGRAL
  52. GRB 240805A: Swift detection of a burst
  53. GRB 240730A: Swift-BAT refined analysis
  54. GRB240730A: BOOTES-5/JGT early optical upper limit
  55. Swift GRB 240730A: Global MASTER-Net observations report
  56. GRB 240730A: Swift-XRT refined Analysis
  57. GRB 240715A: Swift-XRT afterglow detection
  58. GRB 240730A: KAIT Optical Upper Limit
  59. GRB 240730A: Swift/UVOT Upper Limits
  60. GRB 240730A: Enhanced Swift-XRT position
  61. GRB 240730A: Swift detection of a burst
  62. GRB 240727A: Swift-BAT refined analysis
  63. LIGO/Virgo/KAGRA S240615dg: GRAWITA wide-field optical observations
  64. GRB 240727A: observations of optical counterpart.
  65. GRB 240727B: Swift-XRT observations
  66. GRB 240727A: Swift/UVOT detection
  67. GRB 240727A: NOT optical observation
  68. GRB 240727A: JinShan optical upper limits
  69. GRB 240727A Bassano Bresciano Observatory upper limit
  70. GRB 240727A: Swift-XRT refined Analysis
  71. GRB 240727A: Enhanced Swift-XRT position
  72. GRB 240727B: Fermi GBM Observation
  73. Swift GRB240727.16: Global MASTER-Net observations report
  74. GRB 240727B: Swift ToO observations
  75. GRB 240727B: Swift/BAT-GUANO arcminute localization of a long burst
  76. GRB240727A: Skynet Optical Afterglow Observations
  77. GRB 240727A: TRT optical afterglow detection
  78. GRB 240727A: KAIT Optical Afterglow Candidate
  79. GRB 240727A: Swift detection of a burst
  80. Swift Trigger 1244778 is not a GRB
  81. Swift GRB240725.11: Global MASTER-Net observations report
  82. GRB 240720A: Swift-BAT refined analysis
  83. LIGO/Virgo/KAGRA S240716b: Upper limits from Swift/BAT-GUANO
  84. LIGO/Virgo/KAGRA S240703ad: Upper limits from Swift/BAT-GUANO
  85. GRB 240720A: AstroSat CZTI detection
  86. GRB 240720A: Fermi GBM observation
  87. GRB 240720A: Swift detection of a burst
  88. Swift GRB240720.02: Global MASTER-Net observations report
  89. GRB 240718A: Fermi-LAT Detection
  90. GRB 240712A: Swift-BAT refined analysis
  91. GRB 240715A: Swift/UVOT observations of the XRT sources.
  92. GRB 240715A: Swift-XRT observations
  93. GRB240713A: Swift/UVOT Upper LImits
  94. EP240708a: X-ray follow-up observations with Swift/XRT
  95. GRB 240713A: Swift-XRT observations
  96. GRB 240715A: TRT optical upper limit on one Swift/XRT candidate
  97. GRB 240712A: Swift-XRT refined Analysis
  98. GRB 240715A: Swift ToO observations
  99. GRB 240712A ATCA radio observations
  100. IPN triangulation of GRB 240715A (short)

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