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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').

17858 results found.

  1. GRB 241108A: Swift-XRT observations
  2. GRB 241108A: Swift ToO observations
  3. GRB 241030A: TESS observations
  4. GRB 241105A: EP-FXT follow-up observations
  5. GRB 241105A: SVOM/GRM observation
  6. GRB 241105a: PRIME near-infrared upper limits
  7. GRB 241105A: Swift/UVOT Detection
  8. GRB 241105A: Swift/BAT-GUANO refined analysis of short burst with extended emission
  9. GRB 241030A: optical afterglow detection from the INAF Asiago Observatory
  10. GRB 241105A: BOOTES-7 optical detection
  11. GRB241105A: Fermi GBM Observation of a Short Burst with Extended Emission
  12. GRB 241105A: Swift-XRT afterglow detection
  13. GRB 241104A: Swift-XRT observations
  14. GRB 241105A: Swift ToO observations
  15. GRB 241105A: Swift/BAT-GUANO arcminute localization of a short burst
  16. GRB 241104A: Swift ToO observations
  17. GRB 241030A: GRBAlpha detection
  18. EP241103a: GIT optical upper limit
  19. EP241103a: GOTO optical upper limit
  20. EP241103a: Swift XRT detection and improved X-ray position
  21. GRB 241030A: Swift-UVOT observations of the optical prompt flare
  22. GRB 241030A: Rapid release of TESS data.
  23. Swift GRB 241101A: Global MASTER-Net observations report
  24. GRB 241101A: FRAM-ORM optical limit
  25. GRB 241101A: Swift-BAT refined analysis
  26. GRB 241030B: Swift-XRT refined Analysis
  27. GRB 241030A / EP241030a: GMG possible spectroscopic redshift at z ~ 1.4
  28. GRB 241101A: Swift detection of a burst
  29. GRB 241030B: Montarrenti Observatory optical upper limit
  30. GRB 241030A / EP241030a: FTW Optical and NIR observations of the optical counterpart
  31. GRB 241030A: Fermi GBM Observation
  32. GRB 241030B: LCOGT Optical Upper Limits
  33. GRB 241030B: Swift-BAT refined analysis
  34. GRB 241030A: Swift-BAT refined analysis
  35. GRB 241030B: Swift/UVOT Detection
  36. GRB 241029A: LCO optical detection
  37. Swift GRB241030.77: Global MASTER-Net observations report
  38. GRB 241030B: SVOM/GRM observation
  39. GRB 241030B : MITSuME Akeno optical upper limits
  40. GRB 241030A: COLIBRI Continuing Detection of the Afterglow
  41. GRB 241030B: COLIBRÍ Upper Limits on the Optical Counterpart
  42. GRB241030B: Fermi GBM Observation
  43. GRB 241030A: detection of the bright optical counterpart in ATLAS forced photometry
  44. GRB 241030B: Enhanced Swift-XRT position
  45. GRB 241030B: optical observations from the INAF Asiago Observatory
  46. EP241021a: Swift-UVOT detection
  47. GRB241030B: GRANDMA/TAROT Upper Limit
  48. GRB 241030A: Swift-XRT refined Analysis
  49. GRB 241030B: AKO Optical Afterglow Detection
  50. GRB 241030B: Nanshan/HMT optical afterglow detection
  51. GRB 241030B: SVOM/ECLAIRs detection of a burst
  52. GRB 241030B: Prompt enhanced Swift-XRT position
  53. Konus-Wind detection of GRB 241030A
  54. GRB 241030B: Swift detection of a burst
  55. GRB 241030A: Fermi-LAT detection
  56. GRB 241030A: AKO Optical Afterglow Detection
  57. Swift GRB 241030A: Global MASTER-Net observations report
  58. GRB 241030A: Swift/UVOT Detection
  59. EP 241021a: further Swift-XRT observations and X-ray counterpart detection
  60. GRB 241030A: SVOM/GRM observation
  61. GRB 241026A: Swift-BAT refined analysis
  62. GRB 241030A: SVOM/C-GFT optical observations
  63. GRB 241030A: Multiband optical detection with Mephisto
  64. GRB 241030A: SVOM/VT optical afterglow observations
  65. GRB 241025A: The discovery of a BdHN I from data of Swift, Fermi, SVOM and Einstein Probe telescopes
  66. GRB 241030A : MITSuME Akeno optical afterglow detection
  67. GRB 241030A: Enhanced Swift-XRT position
  68. GRB 241030A: TRT optical observations
  69. GRB 241030A: ULL-ASTRO-MASTER detection of a bright optical counterpart with the LCOGT 40-cm telescope at McDonald Observatory
  70. GRB 241030A: COLIBRÍ Detection of the Bright Optical Counterpart
  71. GRB 241030A: Swift detection of a burst with a bright optical counterpart
  72. GRB 241026A: Swift/UVOT Upper Limits
  73. GRB 241029A: Swift-XRT observations
  74. GRB 241029A: Swift ToO observations
  75. GRB 241026A: the 100th GRB detected by GRBAlpha
  76. Konus-Wind detection of GRB 241025A
  77. GRB 241026A: GECAM detection
  78. GRB 241026A: SVOM/GRM observation
  79. GRB 241025A: Swift/UVOT Detection
  80. GRB 241026A: GROWTH-India Telescope optical observations
  81. GRB 241026A Fermi GBM Analysis
  82. GRB 241026A: J-band observations with WINTER
  83. GRB 241025A: SAO RAS optical observations
  84. GRB 241026A: Las Cumbres optical detection
  85. GRB 241025A: Mondy optical observations
  86. GRB 241026A: Swift-XRT refined Analysis
  87. GRB 241026A: Enhanced Swift-XRT position
  88. GRB 241026A: KAIT optical observations
  89. GRB 241026A: COLIBRÍ Detection of the Optical Counterpart
  90. GRB 241026A: SAO RAS observations of possible optical afterglow
  91. GRB 241026A: Prompt enhanced Swift-XRT position
  92. GRB 241026A: Swift detection of a burst
  93. Swift GRB241026.95: Global MASTER-Net observations report
  94. GRB241025A: 1.3m DFOT optical afterglow detection
  95. GRB 241025A: GROWTH-India Telescope optical observations
  96. GRB 241025A: COLIBRÍ Detection of the Afterglow
  97. GRB 241025A: Swift-XRT refined Analysis
  98. GRB 241025A: Fermi GBM Observation
  99. IPN triangulation of GRB 241022A (short/hard)
  100. LIGO/Virgo/KAGRA S241009l: Upper limits from Swift/BAT-GUANO

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