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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"

21526 results found.

  1. GRB 241228A: Swift-BAT refined analysis
  2. GRB 241228B: Swift/BAT-GUANO localization skymap of a burst
  3. GRB 241229B: Swift detection of a burst
  4. GRB 241228A: Fermi GBM Observation
  5. Swift GRB 241228A: Global MASTER-Net observations report
  6. GRB 241226A: Swift/BAT-GUANO localization skymap of a burst
  7. GRB 241228A: GROWTH-India telescope optical upper limit
  8. GRB 241228B: Swift ToO observations
  9. GRB 241228A: Swift-XRT refined Analysis
  10. GRB 241228A: Swift/UVOT Upper Limits
  11. GRB 241228A: Enhanced Swift-XRT position
  12. GRB 241228A: Swift detection of a burst
  13. GRB 241223A: Swift-XRT observations
  14. GRB241113A: 7DT Optical upper limits
  15. GRB 241223A: GOTO optical observations summary
  16. GRB 241223A: Swift ToO observations
  17. GRB 241218A: Mondy AZT-33IK optical upper limit
  18. GRB 241218A: Swift/UVOT Upper Limits
  19. EP241217a: optical upper limit with the Liverpool Telescope
  20. GRB 241209B: EP-FXT afterglow detection
  21. GRB 241218A: NOT optical upper limits
  22. GRB 241218A: Swift-BAT refined analysis
  23. EP241217a: refined EP-WXT analysis and EP-FXT follow-up observations
  24. GRB 241217A: refined SVOM/MXT data analysis. Long lasting X-ray emission.
  25. GRB 241218A: REM optical upper limit
  26. GRB 241217A/EP241217b: REM optical/NIR upper limits
  27. EP241217a: REM optical/NIR upper limits
  28. GRB 241218a: Liverpool Telescope optical follow-up
  29. GRB 241217a: Liverpool Telescope optical follow-up
  30. GRB 241218A: Swift-XRT refined Analysis
  31. GRB 241209A: ATCA radio follow-up observations
  32. GRB 241218A: LCOGT Optical Upper Limit
  33. GRB 241218A: Enhanced Swift-XRT position
  34. GRB 241218A: Swift detection of a burst
  35. GRB 241217A : SVOM/VT optical afterglow detection
  36. GRB 241217A: Swift-XRT afterglow detection
  37. EP241217a: Swift-XRT Detection
  38. GRB 241214A: GRBAlpha detection
  39. GRB 241213A (EP241213a): GRBAlpha detection
  40. GRB 241209D: GRBAlpha detection
  41. GRB 241213A: Swift-BAT refined analysis
  42. GRB 241214A: Swift/BAT-GUANO localization skymap of a burst
  43. Konus-Wind detection of GRB 241213A (EP 241213a)
  44. GRB 241212A: Swift-XRT observations
  45. GRB 241213B: Swift-XRT observations
  46. GRB 241209D: CALET Gamma-Ray Burst Monitor detection
  47. GRB 241213A: SVOM/VT optical candidate
  48. GRB 241213B: Tiled Swift observations
  49. GRB 241213A: Swift/UVOT Upper Limits
  50. GRB 241213A: Swift-XRT refined Analysis
  51. GRB 241212A: Swift ToO observations
  52. GRB 241213A: LCOGT Optical Upper Limits
  53. EP241213a/GRB241213a: Likely joint detection and INTEGRAL/SPI-ACS counterpart
  54. EP241213a: EP detection of An X-ray Transient
  55. GRB 241213A: REM optical/NIR upper limits
  56. GRB 241213A: Enhanced Swift-XRT position
  57. GRB 241213A: SAO RAS optical upper limit
  58. Swift GRB 241213A: Global MASTER-Net observations report
  59. GRB 241213A: Swift detection of a burst
  60. GRB 241209A: Chandra X-ray Detection
  61. Konus-Wind detection of GRB 241209B
  62. GRB 241209B: GRBAlpha detection
  63. GRB 241129A: Fermi GBM Observation
  64. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  65. GRB 241209D: REM optical/NIR upper limits
  66. Konus-Wind detection of GRB 241209D
  67. GRB 241209B: Swift-XRT afterglow detection
  68. GRB 241209C: Fermi GBM Observation
  69. GRB 241209A: Swift-XRT refined Analysis
  70. GRB 241209D: AstroSat CZTI detection
  71. GRB 241209A: EP-FXT follow-up observations
  72. GRB 241209B: SVOM/VT afterglow detection
  73. GRB 241207B: Fermi GBM Observation
  74. GRB 241209A: BOOTES-7 and 2.2m CAHA early optical upper limits
  75. GRB 241209D: Swift-XRT refined Analysis
  76. GRB 241209D: Fermi GBM Observation
  77. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  78. GRB 241209D: COLIBRÍ detection of the afterglow
  79. GRB 241209A: COLIBRÍ Optical Upper Limit
  80. GRB 241209A: Fermi GBM Observation
  81. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  82. GRB 241209A: GRANDMA/TAROT upper limit
  83. Swift GRB 241209D: Global MASTER-Net observations report
  84. GRB 241209B: Swift ToO observations
  85. GRB 241209A: REM optical/NIR observations
  86. GRB 241209D: Enhanced Swift-XRT position
  87. GRB 241209D: Swift detection of a burst
  88. GRB 241209A: Enhanced Swift-XRT position
  89. GRB 241209A: VLT optical observations
  90. GRB 241209A: GOTO optical upper limits
  91. GRB 241209A: Prompt enhanced Swift-XRT position
  92. GRB 241209A: Swift detection of a short burst
  93. Swift GRB241209.23: Global MASTER-Net observations report
  94. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  95. GRB 241206A: DDOTI Upper Limit on the Afterglow
  96. GRB 241207C: Tiled Swift observations
  97. GRB 241206A: Fermi GBM observation
  98. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  99. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  100. Fermi-GBM Sub-Threshold Detection of GRB 241128A

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