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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"

37569 results found.

  1. GRB 241104A: Swift ToO observations
  2. GRB 241104A: NOT optical non-detection
  3. GRB 241105A: GOTO tentative optical counterpart candidate
  4. Fermi GRB 241105A: Global MASTER-Net observations report
  5. GRB 241104A: SVOM/VT optical candidate
  6. GRB 241105A: Fermi GBM Final Real-time Localization
  7. GRB 241104A/EP241104a: Optical upper limits with Kinder observations
  8. GRB 241104A: COLIBRÍ Upper Limits on the Optical Counterpart
  9. GRB 241104A: SVOM/GRM observation
  10. EP241104a: EP detection of GRB 241104A X-ray emission
  11. GRB 241010A: host galaxy redshift z = 0.977
  12. GRB 241104A : Detection and localization by SVOM/ECLAIRs
  13. GRB 240821A: further radio observations with the VLA
  14. Fermi GRB 241104A: Global MASTER-Net observations report
  15. GRB 241104A: Fermi GBM Final Real-time Localization
  16. GRB 241030A: GRBAlpha detection
  17. Fermi trigger No 752365806: Global MASTER-Net observations report
  18. GRB 241030A: Swift-UVOT observations of the optical prompt flare
  19. GRB 241030A: Rapid release of TESS data.
  20. GRB 241029A: GRBAlpha detection
  21. Kinder optical follow-up observations of EP241021a, EP241026b, and EP241030a/GRB241030A
  22. GRB241030A: OHP/T193 optical observations
  23. EP241030a: Futher EP-FXT observation of the X-ray Afterglow of GRB 241030A
  24. Swift GRB 241101A: Global MASTER-Net observations report
  25. GRB 241101A: FRAM-ORM optical limit
  26. GRB 241030A/EP241030a: TNOT observations of the optical counterpart
  27. EP241021a: Upper limit from Konus-Wind observations
  28. GRB 241101A: Swift-BAT refined analysis
  29. GRB 241030A: further SAO RAS optical observations
  30. GRB 241030A: Optical Observations via Virtual Telescope Project
  31. GRB 241030B: Swift-XRT refined Analysis
  32. GRB 241026A: SAO RAS optical observations
  33. GRB 241030A / EP241030a: GMG possible spectroscopic redshift at z ~ 1.4
  34. EP241030a: EP/FXT observation of GRB 241030A X-ray Afterglow
  35. GRB 241101A: Swift detection of a burst
  36. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits (duplicate submission of 38023)
  37. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits
  38. GRB 241030A: Palomar 1-m telescope COSMOS optical observations
  39. GRB 241030B: Montarrenti Observatory optical upper limit
  40. GRB 241030A / EP241030a: FTW Optical and NIR observations of the optical counterpart
  41. Fermi trigger No 752083996: Global MASTER-Net observations report
  42. GRB 241030A: SAO RAS optical observations
  43. GRB 241030A: Fermi GBM Observation
  44. GRB 241030B : GIT optical upper limits
  45. GRB 241030B: LCOGT Optical Upper Limits
  46. GRB 241030B: Swift-BAT refined analysis
  47. GRB 241030A: Swift-BAT refined analysis
  48. GRB 241029A: COLIBRI Detection of the Optical Counterpart
  49. GRB 241030B: Swift/UVOT Detection
  50. GRB 241029A: LCO optical detection
  51. Fermi trigger No 752006065: Global MASTER-Net observations report
  52. GRB 241030B: GTC/OSIRIS+ tentative spectroscopic redshift z = 2.82
  53. GRB 241030B: SVOM/GRM observation
  54. GRB 241030B : MITSuME Akeno optical upper limits
  55. GRB 241030A: COLIBRI Continuing Detection of the Afterglow
  56. GRB 241030B: SVOM/VT optical afterglow observations
  57. GRB 241030B: COLIBRÍ Upper Limits on the Optical Counterpart
  58. EP241030a: EP detection of GRB 241030A X-ray Afterglow
  59. GRB241030B: Fermi GBM Observation
  60. GRB 241030B: BTA observations
  61. GRB 241029A: SVOM/VT optical afterglow observations
  62. GRB 241030A: detection of the bright optical counterpart in ATLAS forced photometry
  63. GRB 241030B: Enhanced Swift-XRT position
  64. GRB 241030B: optical observations from the INAF Asiago Observatory
  65. GRB241030B: GRANDMA/TAROT Upper Limit
  66. GRB 241030A: Swift-XRT refined Analysis
  67. GRB 241030B: SAO RAS optical observations
  68. GRB 241030B: AKO Optical Afterglow Detection
  69. GRB 241030B: Nanshan/HMT optical afterglow detection
  70. GRB 241030B: SVOM/ECLAIRs detection of a burst
  71. GRB 241030B: Prompt enhanced Swift-XRT position
  72. Konus-Wind detection of GRB 241030A
  73. GRB 241030B: Swift detection of a burst
  74. GRB 241030B: Fermi GBM Final Real-time Localization
  75. GRB 241030A: Fermi-LAT detection
  76. GRB 240912A: radio detection with the VLA
  77. Fermi GRB 241030A: Global MASTER-Net observations report
  78. GRB 241030A: AKO Optical Afterglow Detection
  79. Swift GRB 241030A: Global MASTER-Net observations report
  80. GRB 241030A: Swift/UVOT Detection
  81. EP 241021a: further Swift-XRT observations and X-ray counterpart detection
  82. GRB 241030A: SVOM/GRM observation
  83. GRB 241026A: Swift-BAT refined analysis
  84. GRB 241030A: SVOM/C-GFT optical observations
  85. GRB 241026A: LBT optical observations
  86. GRB 241030A: Multiband optical detection with Mephisto
  87. GRB 241030A: SVOM/VT optical afterglow observations
  88. GRB 241025A: The discovery of a BdHN I from data of Swift, Fermi, SVOM and Einstein Probe telescopes
  89. GRB 241030A : MITSuME Akeno optical afterglow detection
  90. GRB 241030A: Enhanced Swift-XRT position
  91. GRB 241029A: GROWTH-India Telescope optical follow up
  92. GRB 241030A: TRT optical observations
  93. GRB 241030A: Keck/LRIS spectroscopic redshift z = 1.411
  94. GRB 241030A: ULL-ASTRO-MASTER detection of a bright optical counterpart with the LCOGT 40-cm telescope at McDonald Observatory
  95. GRB 241030A: COLIBRÍ Detection of the Bright Optical Counterpart
  96. GRB 241030A: Swift detection of a burst with a bright optical counterpart
  97. GRB 241030A: Fermi GBM Final Real-time Localization
  98. GRB 241029A: SAO RAS optical observations
  99. GRB 241026A: SAO RAS optical observations
  100. EP240919a / GRB 240919A: ATCA Detection of Radio Counterpart

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