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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"

42902 results found.

  1. GRB 260303A: 1.3m DFOT optical upper limit (duplicate submission)
  2. GRB 260303A: 1.3m DFOT optical upper limit
  3. EP260214b: ATCA 6 GHz observations
  4. GRB 260211A: SVOM/VT optical rebrightening at 20 days after the burst, SN candidate
  5. GRB 260303A: SVOM/ECLAIRs refined analysis
  6. Fermi GRB 260305A: Global MASTER-Net observations report
  7. GRB 260305A: Fermi GBM Final Real-time Localization
  8. GRB 260303B: AstroSat CZTI detection
  9. GRB 260304A: AstroSat CZTI detection of a long burst
  10. SVOM/sb26030408: SVOM detection of an X-ray transient likely associated with Beta Persei
  11. GRB 260303A: SVOM/VT optical observations
  12. GRB 260303A: J-band observations with WINTER
  13. GRB 260303B: NuSTAR detection of prompt emission
  14. EP260302a: Global MASTER-Net observations report
  15. Fermi GRB 260303B: Global MASTER-Net observations report
  16. IceCube-260217A: No Candidate Transients from the Zwicky Transient Facility
  17. GRB 260228A: SVOM/ECLAIRs refined analysis
  18. GRB 260225A: SVOM/ECLAIRs refined analysis
  19. GRB 260303B: Fermi GBM Final Real-time Localization
  20. EP260302a: analysis of the follow-up EP-FXT observation
  21. EP260227a: Gemini-South optical observations
  22. EP260302a: LCO observations
  23. EP260302a: BOOTES-7 optical counterpart detection at early times
  24. GRB 260303A: SVOM/COLIBRÍ (FM-GFT) optical counterpart candidate
  25. GRB 260303A: SVOM detection of a burst
  26. GRB 260228A: EP-FXT follow-up observation
  27. EP260302a: Einstein Probe detection of an X-ray transient
  28. The EP-WXT trigger 01709258736: Las Cumbres discovery of the optical counterpart
  29. GRB 251130B: TERI Gamma-ray detection
  30. GRB 260208A: TERI Gamma-ray detection
  31. GRB 260302A: Fermi GBM Final Real-time Localization
  32. EP260227a: Mondy optical observations
  33. GRB 260228A: CAHA 2.2m telescope optical upper limit
  34. EP260227a: Mephisto optical detection
  35. GRID detection of GRB 260225D
  36. EP-WXT trigger 01709258652: 50cm Telescope multi-band observations
  37. EP260227a: further LCO observations
  38. EP260227a: SVOM/VT optical observation
  39. GRB 260228A: SVOM/VT optical upper limits
  40. GRB 260225D: SVOM/GRM observation
  41. GRB 260225B: SVOM/GRM observation
  42. GRB 260228A: SVOM detection of a burst
  43. EP260227a: Liverpool Telescope optical observations
  44. EP260227a: LCOGT Optical Observations
  45. GRB 260226A: Asiago r-band upper limit
  46. EP260227a: Thai National Telescope observations
  47. EP260227a: likely GTC/OSIRIS+ redshift z = 2.714
  48. EP260227a: Liverpool Telescope observations
  49. EP260227a: COLIBRÍ optical observations
  50. EP260227a: NOT optical observations
  51. GRB 260225A: SVOM/VT optical continued observations and upper limit
  52. GRID detection of GRB 260223A
  53. EP260227a: Global MASTER-Net observations report
  54. EP260227a: Einstein Probe detection of an X-ray transient and refined analysis
  55. The EP-WXT trigger 01709258681 (EP260227a?): Las Cumbres follow-up observation of the optical counterpart
  56. EP/WXT trigger 01709258681 (EP260227a?): LCO candidate afterglow
  57. IceCube cascade alert 142200_1517143 retraction
  58. GRB 260226A: Insight-HXMT/HE detection of the very bright burst
  59. Konus-Wind detection of GRB 260226A
  60. GRB 260223A: 7DT detection and Medium-band SED of Afterglow
  61. EP260214a: VLT/FORS2 optical observations
  62. GRB 260225A: WINTER J-band upper limit
  63. GRB 260226A: CALET Gamma-Ray Burst Monitor detection
  64. GRB 260226A: LCOGT Optical Upper Limit
  65. EP-WXT trigger 01709258652: SVOM/C-GFT confirmation of a stellar flare
  66. GRB 260225D: Glowbug gamma-ray detection of a likely short burst
  67. GRB 260226A: Glowbug gamma-ray detection
  68. GRB 260226A: NuSTAR detection of bright prompt emission
  69. GRB 260226A : GROWTH-India Telescope optical observations
  70. GRB 260226A: LAST optical upper limit
  71. GRB 260226A: Fermi GBM observation
  72. GRB 260226A: Fermi-LAT refined analysis
  73. The EP-WXT trigger 01709258652 is likely a flaring star
  74. LAT GRB260226.44: Global MASTER-Net observations report
  75. Fermi GRB 260226A: Global MASTER-Net observations report
  76. GRB 260226A: AstroSat CZTI detection of bright long burst
  77. EP260214a: VLA 6 GHz detection
  78. GRB 260226A: Fermi-LAT detection of a bright burst
  79. EP260224a: LCO optical upper limits
  80. GRB260225A: SVOM/ECLAIRs refined position
  81. GRB 260226A: Fermi GBM Final Real-time Localization
  82. GRB 260225A: EP-FXT follow-up observation
  83. GRB 260225A: SVOM/VT optical observation
  84. GRB 260225A: SVOM/COLIBRÍ (FM-GFT) Detection of an Optical Counterpart Candidate
  85. GRB 260225C: Fermi GBM Final Real-time Localization
  86. GRB 260223A: Fermi GBM Observation
  87. GRB 260225A: SVOM/VT optical upper limits
  88. GRB 260225B: Fermi GBM Final Real-time Localization
  89. EP260126a: VLA 6 GHz detection
  90. EP260223a: Liverpool Telescope upper limits
  91. GRB 260225A: SVOM/COLIBRÍ (FM-GFT) optical upper limits
  92. GRB 260225A: SVOM detection of a burst
  93. EP260224a: Einstein Probe detection of an X-ray transient
  94. EP 260225.148: COLIBRÍ Confirmation of flaring star
  95. EP260223a: Xinglong optical upper limit
  96. The EP-WXT trigger 01709258631 is likely a flaring star
  97. GRB 260223A: Glowbug gamma-ray detection
  98. EP260213a: Mephisto optical upper limits
  99. EP260223a: EP-FXT follow-up observation
  100. sb26021801: SVOM/VT optical upper limits

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