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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"

19663 results found.

  1. GRB 240730A: Swift-BAT refined analysis
  2. GRB240730A: BOOTES-5/JGT early optical upper limit
  3. Swift GRB 240730A: Global MASTER-Net observations report
  4. GRB 240730A: Swift-XRT refined Analysis
  5. GRB 240715A: Swift-XRT afterglow detection
  6. GRB 240730A: KAIT Optical Upper Limit
  7. GRB 240730A: Swift/UVOT Upper Limits
  8. GRB 240730A: Enhanced Swift-XRT position
  9. GRB 240730A: Swift detection of a burst
  10. GRB 240727A: Swift-BAT refined analysis
  11. LIGO/Virgo/KAGRA S240615dg: GRAWITA wide-field optical observations
  12. GRB 240727A: observations of optical counterpart.
  13. GRB 240727B: Swift-XRT observations
  14. GRB 240727A: Swift/UVOT detection
  15. GRB 240727A: NOT optical observation
  16. GRB 240727A: JinShan optical upper limits
  17. GRB 240727A Bassano Bresciano Observatory upper limit
  18. GRB 240727A: Swift-XRT refined Analysis
  19. GRB 240727A: Enhanced Swift-XRT position
  20. GRB 240727B: Fermi GBM Observation
  21. Swift GRB240727.16: Global MASTER-Net observations report
  22. GRB 240727B: Swift ToO observations
  23. GRB 240727B: Swift/BAT-GUANO arcminute localization of a long burst
  24. GRB240727A: Skynet Optical Afterglow Observations
  25. GRB 240727A: TRT optical afterglow detection
  26. GRB 240727A: KAIT Optical Afterglow Candidate
  27. GRB 240727A: Swift detection of a burst
  28. Swift Trigger 1244778 is not a GRB
  29. Swift GRB240725.11: Global MASTER-Net observations report
  30. GRB 240720A: Swift-BAT refined analysis
  31. LIGO/Virgo/KAGRA S240716b: Upper limits from Swift/BAT-GUANO
  32. LIGO/Virgo/KAGRA S240703ad: Upper limits from Swift/BAT-GUANO
  33. GRB 240720A: AstroSat CZTI detection
  34. GRB 240720A: Fermi GBM observation
  35. GRB 240720A: Swift detection of a burst
  36. Swift GRB240720.02: Global MASTER-Net observations report
  37. GRB 240718A: Fermi-LAT Detection
  38. GRB 240712A: Swift-BAT refined analysis
  39. GRB 240715A: Swift/UVOT observations of the XRT sources.
  40. GRB 240715A: Swift-XRT observations
  41. GRB240713A: Swift/UVOT Upper LImits
  42. EP240708a: X-ray follow-up observations with Swift/XRT
  43. GRB 240713A: Swift-XRT observations
  44. GRB 240715A: TRT optical upper limit on one Swift/XRT candidate
  45. GRB 240712A: Swift-XRT refined Analysis
  46. GRB 240715A: Swift ToO observations
  47. GRB 240712A ATCA radio observations
  48. IPN triangulation of GRB 240715A (short)
  49. GW s240422ed: Swift UVOT follow-up
  50. GRB 240712A: Swift/UVOT Upper Limits
  51. The EP-WXT source triggered on July 14th is likely a flaring star
  52. GRB 240713A: Tiled Swift observations
  53. GRB 240712A: Swift detection of a burst
  54. EP240708a: X-ray follow-up observations with EP/FXT and Swift/XRT
  55. EP240708a: EP-WXT detection of a fast X-ray transient
  56. LIGO/Virgo S240615dg: Swift XRT observations, 28 futher X-ray sources
  57. IPN triangulation of GRB 240628B (short)
  58. EP240703a and EP240703b: Swift/XRT upper limits
  59. EP240703c: Kinder optical follow-up and Swift XRT observations
  60. EP240703c: EP-WXT detection of an X-ray transient
  61. IPN triangulation of GRB 240627A
  62. EP240703b: EP-WXT detection of a fast X-ray transient
  63. EP240702a: Swift/XRT upper limit
  64. EP240703a: EP-WXT detection of a fast X-ray transient
  65. EP240702a: EP-WXT detection of a fast X-ray transient
  66. LIGO/Virgo/KAGRA S240627by: Upper limits from Swift/BAT-GUANO
  67. IPN triangulation of GRB 240619C
  68. GRB 240624A: Swift-BAT refined analysis
  69. Konus-Wind detection of GRB 240619A
  70. GRB240624A: Fermi GBM Observation
  71. LIGO/Virgo/KAGRA S240622h: Upper limits from Swift/BAT-GUANO
  72. LIGO/Virgo/KAGRA S240621dy: Upper limits from Swift/BAT-GUANO
  73. LIGO/Virgo/KAGRA S240618ah: Upper limits from Swift/BAT-GUANO
  74. Swift GRB 240624A: Global MASTER-Net observations report
  75. GRB 240624A: Swift detection of a burst
  76. GRB 240529A: JinShan optical observations
  77. IPN triangulation of GRB 240615A (short)
  78. EP240618a: Swift/XRT upper limit
  79. EP240617a: tentative Swift/XRT detection of the afterglow
  80. GRB 240619A: Swift-XRT probable afterglow detection
  81. GRB 240619A: Swift ToO observations
  82. GRB 240615A: NOT optical observations
  83. GRB 240615A: possible transient detection from Wendelstein observations
  84. LIGO/Virgo S240615dg: Swift XRT observations, 39 X-ray sources
  85. GRB240615A: 1.3m DFOT optical upper limit
  86. LIGO/Virgo/KAGRA S240615ea: Upper limits from Swift/BAT-GUANO
  87. LIGO/Virgo/KAGRA S240615dg: Upper limits from Swift/BAT-GUANO
  88. GRB 240615A: J-band upper limits from WINTER
  89. GRB 240615A: Fermi GBM Observation
  90. GRB 240615A: Swift-XRT observations
  91. GRB 240615A: GECAM detection
  92. GRB 240615A: FLWO-1.2m optical upper limits
  93. Konus-Wind detection of GRB 240615A (short/hard)
  94. GRB 240615A: GOTO optical upper limits
  95. GRB 240615A: Swift ToO observations
  96. GRB 240615A: Swift/BAT-GUANO arcminute localization of a short burst
  97. EXO 0748-676: Swift-BAT refined analysis
  98. GRB240529A: 3.6m TNG NIR detection 8d after the burst
  99. GRB 240529A: LBT optical detection and late temporal decay
  100. GRB 240529A : MITSuME Akeno optical afterglow detection

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