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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"

26514 results found.

  1. EP260306a: COLIBRÍ optical observations of the fading and red counterpart
  2. EP260306a: Einstein Probe detection of an X-ray transient
  3. EP260302a: Optical afterglow rebrightening
  4. GRB 260228A: further EP-FXT observations and X-ray afterglow confirmation
  5. GRB 260303A: 1.3m DFOT optical upper limit
  6. EP260214b: ATCA 6 GHz observations
  7. GRB 260211A: SVOM/VT optical rebrightening at 20 days after the burst, SN candidate
  8. GRB 260303A: SVOM/ECLAIRs refined analysis
  9. GRB 260303B: AstroSat CZTI detection
  10. GRB 260304A: AstroSat CZTI detection of a long burst
  11. SVOM/sb26030408: SVOM detection of an X-ray transient likely associated with Beta Persei
  12. GRB 260303A: SVOM/VT optical observations
  13. GRB 260303A: J-band observations with WINTER
  14. GRB 260303B: NuSTAR detection of prompt emission
  15. IceCube-260217A: No Candidate Transients from the Zwicky Transient Facility
  16. GRB 260228A: SVOM/ECLAIRs refined analysis
  17. GRB 260225A: SVOM/ECLAIRs refined analysis
  18. EP260302a: analysis of the follow-up EP-FXT observation
  19. EP260302a: LCO observations
  20. EP260302a: BOOTES-7 optical counterpart detection at early times
  21. GRB 260303A: SVOM/COLIBRÍ (FM-GFT) optical counterpart candidate
  22. GRB 260303A: SVOM detection of a burst
  23. GRB 260228A: EP-FXT follow-up observation
  24. EP260302a: Einstein Probe detection of an X-ray transient
  25. GRB 251130B: TERI Gamma-ray detection
  26. GRB 260208A: TERI Gamma-ray detection
  27. GRB 260228A: CAHA 2.2m telescope optical upper limit
  28. GRB 260228A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  29. EP260227a: Mephisto optical detection
  30. GRID detection of GRB 260225D
  31. EP-WXT trigger 01709258652: 50cm Telescope multi-band observations
  32. EP260227a: SVOM/VT optical observation
  33. GRB 260228A: SVOM/VT optical upper limits
  34. GRB 260225D: SVOM/GRM observation
  35. EP260227A: 3.6m DOT optical afterglow detection
  36. GRB 260225B: SVOM/GRM observation
  37. GRB 260228A: SVOM detection of a burst
  38. EP260227a: Liverpool Telescope optical observations
  39. EP260227a: Thai National Telescope observations
  40. EP260227a: Liverpool Telescope observations
  41. EP260227a: COLIBRÍ optical observations
  42. GRB 260225A: SVOM/VT optical continued observations and upper limit
  43. GRID detection of GRB 260223A
  44. EP260227a: Einstein Probe detection of an X-ray transient and refined analysis
  45. The EP-WXT trigger 01709258681 (EP260227a?): Las Cumbres follow-up observation of the optical counterpart
  46. IceCube cascade alert 142200_1517143 retraction
  47. GRB 260226A: Insight-HXMT/HE detection of the very bright burst
  48. Konus-Wind detection of GRB 260226A
  49. GRB 260223A: 7DT detection and Medium-band SED of Afterglow
  50. EP260214a: VLT/FORS2 optical observations
  51. GRB 260225A: WINTER J-band upper limit
  52. GRB 260226A: CALET Gamma-Ray Burst Monitor detection
  53. GRB 260226A: COLIBRÍ optical upper limits
  54. EP-WXT trigger 01709258652: SVOM/C-GFT confirmation of a stellar flare
  55. GRB 260225D: Glowbug gamma-ray detection of a likely short burst
  56. GRB 260226A: Glowbug gamma-ray detection
  57. GRB 260226A: NuSTAR detection of bright prompt emission
  58. GRB 260226A : GROWTH-India Telescope optical observations
  59. GRB 260226A: LAST optical upper limit
  60. GRB 260226A: Fermi GBM observation
  61. GRB 260226A: Fermi-LAT refined analysis
  62. The EP-WXT trigger 01709258652 is likely a flaring star
  63. GRB 260226A: AstroSat CZTI detection of bright long burst
  64. EP260214a: VLA 6 GHz detection
  65. GRB 260226A: Fermi-LAT detection of a bright burst
  66. GRB260225A: SVOM/ECLAIRs refined position
  67. GRB 260225A: EP-FXT follow-up observation
  68. GRB 260225A: SVOM/VT optical observation
  69. GRB 260225A: SVOM/COLIBRÍ (FM-GFT) Detection of an Optical Counterpart Candidate
  70. GRB 260223A: Fermi GBM Observation
  71. GRB 260225A: SVOM/VT optical upper limits
  72. EP260126a: VLA 6 GHz detection
  73. EP260223a: Liverpool Telescope upper limits
  74. GRB 260225A: SVOM/COLIBRÍ (FM-GFT) optical upper limits
  75. GRB 260225A: SVOM detection of a burst
  76. EP260224a: Einstein Probe detection of an X-ray transient
  77. EP 260225.148: COLIBRÍ Confirmation of flaring star
  78. EP260223a: Xinglong optical upper limit
  79. GRB 260223A: Glowbug gamma-ray detection
  80. EP260213a: Mephisto optical upper limits
  81. EP260223a: EP-FXT follow-up observation
  82. sb26021801: SVOM/VT optical upper limits
  83. GRB 260223A: COLIBRÍ optical afterglow decay confirmation
  84. sb26021801: SVOM/C-GFT upper limit
  85. EP260223a: COLIBRÍ optical upper limits
  86. EP260223a: Einstein Probe detection of an X-ray transient
  87. GRB 260223A: SVOM/VT optical observation
  88. GRB 260223A: SVOM/GRM observation
  89. GRB 260223A: COLIBRÍ further optical observations and a brightening
  90. EP260221a: Optical upper limit with Kinder observations
  91. GRB 260223A: COLIBRÍ optical observations
  92. EP260221a: Liverpool Telescope detection of COLIBRÍ counterpart candidate
  93. EP260221a: COLIBRÍ optical counterpart candidate
  94. EP260221a: EP-FXT follow-up observation
  95. EP260221a: Xinglong optical upper limit
  96. ZTF26aaglqak/AT2026dbl: COLIBRÍ Optical Observations
  97. EP260221a: GOTO optical upper limit
  98. EP260221a: COLIBRÍ optical upper limit
  99. SVOM alert sb26021801: LCO optical upper limit
  100. EP260221a: Einstein Probe detection of an X-ray transient

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