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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"

37677 results found.

  1. GRB 241105A: Swift-XRT afterglow detection
  2. GRB 241105A: VLT/FORS2 spectroscopic redshift z = 2.681
  3. GRB 241104A: Swift-XRT observations
  4. GRB 240511A: LCO upper limits
  5. GRB 241104A: Fermi GBM Observation
  6. GRB 241104A: The SVOM/VT candidate in GCN circular 38086 is not an astrophysical source
  7. GRB 241105A: Swift ToO observations
  8. GRB 241105A: Swift/BAT-GUANO arcminute localization of a short burst
  9. GRB 241104A: Swift ToO observations
  10. GRB 241104A: NOT optical non-detection
  11. GRB 241105A: GOTO tentative optical counterpart candidate
  12. Fermi GRB 241105A: Global MASTER-Net observations report
  13. GRB 241104A: SVOM/VT optical candidate
  14. GRB 241105A: Fermi GBM Final Real-time Localization
  15. GRB 241104A/EP241104a: Optical upper limits with Kinder observations
  16. GRB 241104A: COLIBRÍ Upper Limits on the Optical Counterpart
  17. GRB 241104A: SVOM/GRM observation
  18. EP241104a: EP detection of GRB 241104A X-ray emission
  19. GRB 241010A: host galaxy redshift z = 0.977
  20. GRB 241104A : Detection and localization by SVOM/ECLAIRs
  21. GRB 240821A: further radio observations with the VLA
  22. Fermi GRB 241104A: Global MASTER-Net observations report
  23. GRB 241104A: Fermi GBM Final Real-time Localization
  24. GRB 241030A: GRBAlpha detection
  25. Fermi trigger No 752365806: Global MASTER-Net observations report
  26. GRB 241030A: Swift-UVOT observations of the optical prompt flare
  27. GRB 241030A: Rapid release of TESS data.
  28. GRB 241029A: GRBAlpha detection
  29. Kinder optical follow-up observations of EP241021a, EP241026b, and EP241030a/GRB241030A
  30. GRB241030A: OHP/T193 optical observations
  31. EP241030a: Futher EP-FXT observation of the X-ray Afterglow of GRB 241030A
  32. Swift GRB 241101A: Global MASTER-Net observations report
  33. GRB 241101A: FRAM-ORM optical limit
  34. GRB 241030A/EP241030a: TNOT observations of the optical counterpart
  35. EP241021a: Upper limit from Konus-Wind observations
  36. GRB 241101A: Swift-BAT refined analysis
  37. GRB 241030A: further SAO RAS optical observations
  38. GRB 241030A: Optical Observations via Virtual Telescope Project
  39. GRB 241030B: Swift-XRT refined Analysis
  40. GRB 241026A: SAO RAS optical observations
  41. GRB 241030A / EP241030a: GMG possible spectroscopic redshift at z ~ 1.4
  42. EP241030a: EP/FXT observation of GRB 241030A X-ray Afterglow
  43. GRB 241101A: Swift detection of a burst
  44. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits (duplicate submission of 38023)
  45. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits
  46. GRB 241030A: Palomar 1-m telescope COSMOS optical observations
  47. GRB 241030B: Montarrenti Observatory optical upper limit
  48. GRB 241030A / EP241030a: FTW Optical and NIR observations of the optical counterpart
  49. Fermi trigger No 752083996: Global MASTER-Net observations report
  50. GRB 241030A: SAO RAS optical observations
  51. GRB 241030A: Fermi GBM Observation
  52. GRB 241030B : GIT optical upper limits
  53. GRB 241030B: LCOGT Optical Upper Limits
  54. GRB 241030B: Swift-BAT refined analysis
  55. GRB 241030A: Swift-BAT refined analysis
  56. GRB 241029A: COLIBRI Detection of the Optical Counterpart
  57. GRB 241030B: Swift/UVOT Detection
  58. GRB 241029A: LCO optical detection
  59. Fermi trigger No 752006065: Global MASTER-Net observations report
  60. GRB 241030B: GTC/OSIRIS+ tentative spectroscopic redshift z = 2.82
  61. GRB 241030B: SVOM/GRM observation
  62. GRB 241030B : MITSuME Akeno optical upper limits
  63. GRB 241030A: COLIBRI Continuing Detection of the Afterglow
  64. GRB 241030B: SVOM/VT optical afterglow observations
  65. GRB 241030B: COLIBRÍ Upper Limits on the Optical Counterpart
  66. EP241030a: EP detection of GRB 241030A X-ray Afterglow
  67. GRB241030B: Fermi GBM Observation
  68. GRB 241030B: BTA observations
  69. GRB 241029A: SVOM/VT optical afterglow observations
  70. GRB 241030A: detection of the bright optical counterpart in ATLAS forced photometry
  71. GRB 241030B: Enhanced Swift-XRT position
  72. GRB 241030B: optical observations from the INAF Asiago Observatory
  73. GRB241030B: GRANDMA/TAROT Upper Limit
  74. GRB 241030A: Swift-XRT refined Analysis
  75. GRB 241030B: SAO RAS optical observations
  76. GRB 241030B: AKO Optical Afterglow Detection
  77. GRB 241030B: Nanshan/HMT optical afterglow detection
  78. GRB 241030B: SVOM/ECLAIRs detection of a burst
  79. GRB 241030B: Prompt enhanced Swift-XRT position
  80. Konus-Wind detection of GRB 241030A
  81. GRB 241030B: Swift detection of a burst
  82. GRB 241030B: Fermi GBM Final Real-time Localization
  83. GRB 241030A: Fermi-LAT detection
  84. GRB 240912A: radio detection with the VLA
  85. Fermi GRB 241030A: Global MASTER-Net observations report
  86. GRB 241030A: AKO Optical Afterglow Detection
  87. Swift GRB 241030A: Global MASTER-Net observations report
  88. GRB 241030A: Swift/UVOT Detection
  89. EP 241021a: further Swift-XRT observations and X-ray counterpart detection
  90. GRB 241030A: SVOM/GRM observation
  91. GRB 241026A: Swift-BAT refined analysis
  92. GRB 241030A: SVOM/C-GFT optical observations
  93. GRB 241026A: LBT optical observations
  94. GRB 241030A: Multiband optical detection with Mephisto
  95. GRB 241030A: SVOM/VT optical afterglow observations
  96. GRB 241025A: The discovery of a BdHN I from data of Swift, Fermi, SVOM and Einstein Probe telescopes
  97. GRB 241030A : MITSuME Akeno optical afterglow detection
  98. GRB 241030A: Enhanced Swift-XRT position
  99. GRB 241029A: GROWTH-India Telescope optical follow up
  100. GRB 241030A: TRT optical observations

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