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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"

14862 results found.

  1. EP241107a: GSP detects optical counterpart
  2. EP241107a: Gemini-South spectroscopic confirmation (z = 0.456)
  3. GRB 241107A: SVOM/GRM detection of a short burst
  4. GRB 241105A: SVOM/GRM observation
  5. EP241107a: OHP/T193 photometric and spectroscopic observations
  6. GRB 241105a: PRIME near-infrared upper limits
  7. GRB 241105A: ePESSTO+ NTT optical afterglow detection
  8. EP241107a: AKO Optical Afterglow Detection
  9. GRB241105A: Gemini-South Optical Afterglow Detection
  10. EP241107a: EP on-board trigger and autonomous follow-up observation
  11. GRB 241105A: Swift/UVOT Detection
  12. GRB 241030A: optical afterglow detection from the INAF Asiago Observatory
  13. GRB 241105A: BOOTES-7 optical detection
  14. Konus-Wind detection of GRB 241105A (short with extended emission)
  15. Konus-Wind detection of GRB 241021A
  16. GRB 241105A: Swift-XRT afterglow detection
  17. GRB 241105A: VLT/FORS2 spectroscopic redshift z = 2.681
  18. GRB 240511A: LCO upper limits
  19. GRB 241104A: NOT optical non-detection
  20. GRB 241105A: Fermi GBM Final Real-time Localization
  21. GRB 241104A: SVOM/GRM observation
  22. EP241104a: EP detection of GRB 241104A X-ray emission
  23. EP241101a NUTTelA-TAO / BSTI Measurements 2024-11-02
  24. GRB 241104A : Detection and localization by SVOM/ECLAIRs
  25. GRB 241104A: Fermi GBM Final Real-time Localization
  26. GRB 241030A: GRBAlpha detection
  27. EP241101a: EP-FXT observations update
  28. LIGO/Virgo/KAGRA S241104a: Retraction of GW compact binary merger candidate
  29. EP241101a: Possible detection of an optical counterpart with FTW
  30. EP241103a: Swift XRT detection and improved X-ray position
  31. EP241101a: OHP/T193 optical observations
  32. LIGO/Virgo/KAGRA S241102br: MASTER observations and OT detection
  33. LIGO/Virgo/KAGRA S241102br: EP-WXT X-ray follow-up and flux limits
  34. EP241103a: GSP optical upper limit
  35. EP241103a: an X-ray transient detected by Einstein Probe
  36. GRB 241029A: GRBAlpha detection
  37. EP241101a: BOOTES-7 optical upper limit
  38. EP241101a: EP-WXT detection of a fast X-ray transient
  39. GRB 241030A/EP241030a: TNOT observations of the optical counterpart
  40. EP241021a: Upper limit from Konus-Wind observations
  41. EP241021a: Liverpool Telescope optical follow-up observations
  42. GRB 241101A: Swift detection of a burst
  43. GRB 241030B: Montarrenti Observatory optical upper limit
  44. EP241026b: Liverpool Telescope optical follow-up
  45. EP241021a: AMI-LA radio detection
  46. GRB 241029A: COLIBRI Detection of the Optical Counterpart
  47. GRB 241030B: Swift/UVOT Detection
  48. GRB 241029A: LCO optical detection
  49. GRB 241030B: SVOM/GRM observation
  50. GRB 241030A: COLIBRI Continuing Detection of the Afterglow
  51. EP241030a: EP detection of GRB 241030A X-ray Afterglow
  52. GRB 241030B: BTA observations
  53. GRB 241030A: detection of the bright optical counterpart in ATLAS forced photometry
  54. EP241021a: Swift-UVOT detection
  55. GRB241030B: GRANDMA/TAROT Upper Limit
  56. GRB 241030B: AKO Optical Afterglow Detection
  57. GRB 241030B: Nanshan/HMT optical afterglow detection
  58. GRB 241030B: SVOM/ECLAIRs detection of a burst
  59. Konus-Wind detection of GRB 241030A
  60. GRB 241030B: Swift detection of a burst
  61. GRB 241030B: Fermi GBM Final Real-time Localization
  62. GRB 241030A: Fermi-LAT detection
  63. GRB 240912A: radio detection with the VLA
  64. GRB 241030A: AKO Optical Afterglow Detection
  65. GRB 241030A: Swift/UVOT Detection
  66. EP 241021a: further Swift-XRT observations and X-ray counterpart detection
  67. GRB 241030A: SVOM/GRM observation
  68. EP241026b: EP-FXT follow-up observation
  69. GRB 241030A: Multiband optical detection with Mephisto
  70. GRB 241030A : MITSuME Akeno optical afterglow detection
  71. GRB 241030A: Keck/LRIS spectroscopic redshift z = 1.411
  72. GRB 241030A: ULL-ASTRO-MASTER detection of a bright optical counterpart with the LCOGT 40-cm telescope at McDonald Observatory
  73. GRB 241030A: COLIBRÍ Detection of the Bright Optical Counterpart
  74. GRB 241030A: Swift detection of a burst with a bright optical counterpart
  75. GRB 241030A: Fermi GBM Final Real-time Localization
  76. EP240919a / GRB 240919A: ATCA Detection of Radio Counterpart
  77. GRB 241029A: AKO Optical Afterglow Detection
  78. GRB 241029A: GOTO optical afterglow detection
  79. GRB 241029A: MASTER early optical counterpart detection
  80. GRB 241029A: TRT optical afterglow candidate detection
  81. GRB 241029A: SVOM/GRM observation
  82. GRB 241029A : Detection and localization of a bright long GRB by SVOM/ECLAIRs
  83. GRB 241029A: Fermi GBM Final Real-time Localization
  84. EP241021a: Gemini-South detection of optical rebrightening
  85. GRB 241026A: the 100th GRB detected by GRBAlpha
  86. GRB 241026A: TNOT optical counterpart detection
  87. Konus-Wind detection of GRB 241025A
  88. GRB 241026A: GECAM detection
  89. GRB 241026A: SVOM/GRM observation
  90. GRB 241025A: Swift/UVOT Detection
  91. GRB 241026A: Las Cumbres optical detection
  92. EP241026a (GRB 241026A): EP on-board trigger and follow-up observation
  93. EP241026b: EP detection of a fast X-ray transient
  94. GRB 241026A: COLIBRÍ Detection of the Optical Counterpart
  95. GRB 241026A: Swift detection of a burst
  96. GRB 241026A: Fermi GBM Final Real-time Localization
  97. GRB241025A: 1.3m DFOT optical afterglow detection
  98. EP241021a: optical follow-up observations with Xinglong Observatory
  99. ​GRB 241025A: optical photometry from Konkoly
  100. GRB 241025A: COLIBRÍ Detection of the Afterglow

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