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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"

26123 results found.

  1. IPN triangulation of GRB 240807A / EP 240807a
  2. Swift GRB 240809A: Global MASTER-Net observations report
  3. GRB 240809A: JinShan optical observations
  4. GRB 240809A: Enhanced Swift-XRT position
  5. GRB 240809A: Skynet & Photon Ranch Optical Afterglow Observations
  6. GRB 240809A: SVOM/GRM observation
  7. GRB 240809A: Swift detection of a burst with a bright optical counterpart
  8. GRB 240805A: ATCA Radio Upper Limits
  9. GRB 240805B: GIT optical upper limit
  10. GRB 240805B: Swift-BAT refined analysis
  11. GRB 240805A: Swift-BAT refined analysis
  12. Konus-Wind detection of GRB 240805A
  13. GRB 240805B Bassano Bresciano Observatory upper limit
  14. GRB240805A: Fermi GBM Observation
  15. GRB 240805B: JinShan optical afterglow detection
  16. GRB 240805B: AbAO, CrAO, and Terskol optical upper limits
  17. GRB 240805B: NUTTelA-TAO / BSTI Optical Limits
  18. GRB 240805B: Swift-XRT refined Analysis
  19. GRB 240805B: Swift/UVOT Upper Limits
  20. GRB 240805A: Swift/UVOT Upper Limits
  21. GRB 240805B: BTA optical afterglow candidate
  22. GRB 240805A: SVOM/GRM observation
  23. GRB 240805B: Enhanced Swift-XRT position
  24. GRB 240805B: LCOGT Optical Upper Limits
  25. Swift GRB 240805B: Global MASTER-Net observations report
  26. GRB 240805B: JinShan optical upper limits
  27. Swift GRB 240805A: Global MASTER-Net observations report
  28. GRB 240805A: Swift-XRT refined Analysis
  29. GRB 240805B: Swift detection of a burst
  30. GRB 240805A: Fermi-LAT detection
  31. GRB 240805A: INTEGRAL spectral analysis
  32. GRB 240805A: A long GRB detected by INTEGRAL
  33. GRB 240805A: Swift detection of a burst
  34. GRB 240730A: Swift-BAT refined analysis
  35. GRB240730A: BOOTES-5/JGT early optical upper limit
  36. Swift GRB 240730A: Global MASTER-Net observations report
  37. GRB 240730A: Swift-XRT refined Analysis
  38. GRB 240715A: Swift-XRT afterglow detection
  39. GRB 240730A: KAIT Optical Upper Limit
  40. GRB 240730A: Swift/UVOT Upper Limits
  41. GRB 240730A: Enhanced Swift-XRT position
  42. GRB 240730A: Swift detection of a burst
  43. GRB 240727A: Swift-BAT refined analysis
  44. LIGO/Virgo/KAGRA S240615dg: GRAWITA wide-field optical observations
  45. GRB 240727A: observations of optical counterpart.
  46. GRB 240727B: Swift-XRT observations
  47. GRB 240727A: Swift/UVOT detection
  48. GRB 240727A: NOT optical observation
  49. GRB 240727A: JinShan optical upper limits
  50. GRB 240727A Bassano Bresciano Observatory upper limit
  51. GRB 240727A: Swift-XRT refined Analysis
  52. GRB 240727A: Enhanced Swift-XRT position
  53. GRB 240727B: Fermi GBM Observation
  54. Swift GRB240727.16: Global MASTER-Net observations report
  55. GRB 240727B: Swift ToO observations
  56. GRB 240727B: Swift/BAT-GUANO arcminute localization of a long burst
  57. GRB240727A: Skynet Optical Afterglow Observations
  58. GRB 240727A: TRT optical afterglow detection
  59. GRB 240727A: KAIT Optical Afterglow Candidate
  60. GRB 240727A: Swift detection of a burst
  61. Swift Trigger 1244778 is not a GRB
  62. Swift GRB240725.11: Global MASTER-Net observations report
  63. GRB 240720A: Swift-BAT refined analysis
  64. LIGO/Virgo/KAGRA S240716b: Upper limits from Swift/BAT-GUANO
  65. LIGO/Virgo/KAGRA S240703ad: Upper limits from Swift/BAT-GUANO
  66. GRB 240720A: AstroSat CZTI detection
  67. GRB 240720A: Fermi GBM observation
  68. GRB 240720A: Swift detection of a burst
  69. Swift GRB240720.02: Global MASTER-Net observations report
  70. GRB 240718A: Fermi-LAT Detection
  71. GRB 240712A: Swift-BAT refined analysis
  72. GRB 240715A: Swift/UVOT observations of the XRT sources.
  73. GRB 240715A: Swift-XRT observations
  74. GRB240713A: Swift/UVOT Upper LImits
  75. EP240708a: X-ray follow-up observations with Swift/XRT
  76. GRB 240713A: Swift-XRT observations
  77. GRB 240715A: TRT optical upper limit on one Swift/XRT candidate
  78. GRB 240712A: Swift-XRT refined Analysis
  79. GRB 240715A: Swift ToO observations
  80. GRB 240713A: optical upper limits from the INAF Asiago Observatory
  81. GRB 240712A ATCA radio observations
  82. IPN triangulation of GRB 240715A (short)
  83. GW s240422ed: Swift UVOT follow-up
  84. GRB 240712A: Swift/UVOT Upper Limits
  85. The EP-WXT source triggered on July 14th is likely a flaring star
  86. GRB 240713A: Tiled Swift observations
  87. GRB 240713A: J-band upper limit from WINTER
  88. GRB 240713A: NOT optical upper limits on three EP/FXT candidates
  89. GRB 240713A: JinShan optical upper limits
  90. GRB 240712A: Swift detection of a burst
  91. EP240708a: SVOM/C-GFT optical upper limit
  92. EP240708a: X-ray follow-up observations with EP/FXT and Swift/XRT
  93. EP240708a: EP-WXT detection of a fast X-ray transient
  94. LIGO/Virgo S240615dg: Swift XRT observations, 28 futher X-ray sources
  95. IPN triangulation of GRB 240628B (short)
  96. EP240703a and EP240703b: Swift/XRT upper limits
  97. EP240703a: BTA observations
  98. EP240703c: Kinder optical follow-up and Swift XRT observations
  99. EP240703a: Liverpool Telescope optical follow-up observations
  100. EP240703a/GRB 240703A: TRT optical candidate likely not real

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