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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"

32714 results found.

  1. Fermi GRB 260310A: Global MASTER-Net observations report
  2. GRB 260307B: SVOM/ECLAIRs refined analysis
  3. GRB 260208A: radio detection with the VLA
  4. GRB 260307A: Glowbug gamma-ray detection
  5. Fermi GBM Sub-Threshold Detection of GRB 260307B
  6. GRB 260307B: Mephisto optical upper limits
  7. GRB 260307B: possible NOT optical counterpart
  8. GRB 260307B: SVOM/VT upper limit with X band data analysis
  9. Fermi GRB 260307A: Global MASTER-Net observations report
  10. GRB260307B: GROWTH-India Telescope optical upper limit
  11. GRB 260307B: SVOM/VT optical candidate
  12. GRB 260307B: SVOM/C-GFT upper limit
  13. GRB 260211A: late-time NOT i-band observations consistent with archival flux
  14. EP260306a: refined analysis of the EP-WXT and EP-FXT observations
  15. GRB 260207A: TESS Detection and Possible VLA Counterpart
  16. EP260302a: SVOM/VT optical observation
  17. EP260306a: Gemini-North redshift z = 4.773
  18. EP260306a: SVOM/VT optical observation
  19. EP260302a: Gemini-South redshift z = 1.535
  20. EP260306a: COLIBRÍ optical observations of the fading and red counterpart
  21. EP260306a: Einstein Probe detection of an X-ray transient
  22. EP260302a: Optical afterglow rebrightening
  23. GRB 260228A: further EP-FXT observations and X-ray afterglow confirmation
  24. GRB 260303A: 1.3m DFOT optical upper limit (duplicate submission)
  25. GRB 260303A: 1.3m DFOT optical upper limit
  26. EP260214b: ATCA 6 GHz observations
  27. GRB 260211A: SVOM/VT optical rebrightening at 20 days after the burst, SN candidate
  28. GRB 260303A: SVOM/ECLAIRs refined analysis
  29. Fermi GRB 260305A: Global MASTER-Net observations report
  30. GRB 260303B: AstroSat CZTI detection
  31. GRB 260303A: SVOM/VT optical observations
  32. GRB 260303A: J-band observations with WINTER
  33. GRB 260303B: NuSTAR detection of prompt emission
  34. EP260302a: Global MASTER-Net observations report
  35. Fermi GRB 260303B: Global MASTER-Net observations report
  36. IceCube-260217A: No Candidate Transients from the Zwicky Transient Facility
  37. GRB 260228A: SVOM/ECLAIRs refined analysis
  38. GRB 260225A: SVOM/ECLAIRs refined analysis
  39. EP260302a: analysis of the follow-up EP-FXT observation
  40. EP260227a: Gemini-South optical observations
  41. EP260302a: LCO observations
  42. EP260302a: BOOTES-7 optical counterpart detection at early times
  43. GRB 260303A: SVOM/COLIBRÍ (FM-GFT) optical counterpart candidate
  44. GRB 260228A: EP-FXT follow-up observation
  45. GRB 251130B: TERI Gamma-ray detection
  46. GRB 260208A: TERI Gamma-ray detection
  47. EP260227a: Mondy optical observations
  48. GRB 260228A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  49. EP260227a: Mephisto optical detection
  50. GRID detection of GRB 260225D
  51. EP-WXT trigger 01709258652: 50cm Telescope multi-band observations
  52. EP260227a: further LCO observations
  53. EP260227a: SVOM/VT optical observation
  54. GRB 260228A: SVOM/VT optical upper limits
  55. GRB 260225D: SVOM/GRM observation
  56. EP260227A: 3.6m DOT optical afterglow detection
  57. GRB 260225B: SVOM/GRM observation
  58. EP260227a: FTW optical and NIR observations
  59. EP260227a: Liverpool Telescope optical observations
  60. EP260227a: LCOGT Optical Observations
  61. GRB 260226A: Asiago r-band upper limit
  62. EP260227a: Thai National Telescope observations
  63. EP260227a: likely GTC/OSIRIS+ redshift z = 2.714
  64. EP260227a: Liverpool Telescope observations
  65. EP260227a: COLIBRÍ optical observations
  66. EP260227a: NOT optical observations
  67. GRB 260225A: SVOM/VT optical continued observations and upper limit
  68. GRID detection of GRB 260223A
  69. EP260227a: Global MASTER-Net observations report
  70. EP260227a: Einstein Probe detection of an X-ray transient and refined analysis
  71. The EP-WXT trigger 01709258681 (EP260227a?): Las Cumbres follow-up observation of the optical counterpart
  72. GRB 260226A: Insight-HXMT/HE detection of the very bright burst
  73. Konus-Wind detection of GRB 260226A
  74. GRB 260223A: 7DT detection and Medium-band SED of Afterglow
  75. EP260214a: VLT/FORS2 optical observations
  76. GRB 260225A: WINTER J-band upper limit
  77. GRB 260226A: CALET Gamma-Ray Burst Monitor detection
  78. GRB 260226A: COLIBRÍ optical upper limits
  79. GRB 260226A: LCOGT Optical Upper Limit
  80. EP-WXT trigger 01709258652: SVOM/C-GFT confirmation of a stellar flare
  81. GRB 260226A: Glowbug gamma-ray detection
  82. GRB 260226A: NuSTAR detection of bright prompt emission
  83. GRB 260226A : GROWTH-India Telescope optical observations
  84. GRB 260226A: LAST optical upper limit
  85. GRB 260226A: Fermi GBM observation
  86. GRB 260226A: Fermi-LAT refined analysis
  87. Fermi GRB 260226A: Global MASTER-Net observations report
  88. GRB 260226A: AstroSat CZTI detection of bright long burst
  89. EP260214a: VLA 6 GHz detection
  90. GRB 260226A: Fermi-LAT detection of a bright burst
  91. EP260224a: LCO optical upper limits
  92. GRB260225A: SVOM/ECLAIRs refined position
  93. GRB 260225A: EP-FXT follow-up observation
  94. GRB 260225A: SVOM/VT optical observation
  95. GRB 260225A: SVOM/COLIBRÍ (FM-GFT) Detection of an Optical Counterpart Candidate
  96. GRB 260223A: Fermi GBM Observation
  97. GRB 260225A: SVOM/VT optical upper limits
  98. EP260126a: VLA 6 GHz detection
  99. EP260223a: Liverpool Telescope upper limits
  100. GRB 260225A: SVOM/COLIBRÍ (FM-GFT) optical upper limits

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