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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

2482 results found.

  1. Fermi GRB 260628A: Global MASTER-Net observations report
  2. EP260628a: EP-WXT detection of a fast X-ray transient
  3. GRB 260628A: Fermi GBM Final Real-time Localization
  4. The EP-WXT trigger 01709272671 is likely a flaring star
  5. EP260626a: further Liverpool Telescope optical upper limits
  6. EP260626a: COLIBRÍ optical upper limit
  7. EP260626a: Liverpool Telescope upper limits
  8. EP260626a: EP-WXT detection of a fast X-ray transient
  9. EP260623a: TNG NIR afterglow detection
  10. GRB 260618A: Fermi GBM Observation
  11. MASS-Cube (GRID 2.0) detection of GRB 260616B
  12. EP260623a: FTW optical and NIR observations
  13. EP260623a: Liverpool Telescope optical observations
  14. Fermi GBM trigger 804010507/260624677 is not a GRB
  15. GRB 260624A: Fermi GBM Final Real-time Localization
  16. EP260623a:refined analysis of the EP-WXT and EP-FXT observation
  17. EP260623a: WINTER J-band observations
  18. GRB 260617A: Glowbug gamma-ray detection of a short burst
  19. IceCube-260622A: Upper limits from a search for additional neutrino events in IceCube
  20. EP260623a: Optical follow-up observations with Kinder
  21. GRB 260623A: Fermi GBM Final Real-time Localization
  22. EP260623a: SVOM/VT optical observations
  23. EP260623a: TRT optical observations
  24. EP260623a: REM optical/NIR afterglow detection
  25. EP 260623a: COLIBRÍ optical observations
  26. GRB 260616B/EP260616a: Insight-HXMT/HE detection
  27. EP260623a: OSIRIS+/GTC redshift z = 0.703
  28. EP260623a: Einstein Probe detection of an X-ray transient
  29. GRB 260614B: EP-FXT follow-up observation
  30. GRB 260618C: SVOM/ECLAIRs detection of a possible burst through on-ground search
  31. EP260618a: Liverpool Telescope optical observations
  32. GRB 260618B: LCO optical observations
  33. The EP-WXT trigger 01709271197 is likely a flaring star
  34. GRB 260616B/EP260616a: SVOM/GRM detection of a burst
  35. GRB 260618B: Fermi GBM Observation
  36. IceCube-Cascade 260618A: Upper limits from a search for additional neutrino events in IceCube
  37. GRB 260610B: Further GRANDMA Optical Observations and re-brightening detection
  38. GRB 260610B: VLT/FORS2 spectroscopic observation suggests the non-thermal nature of the optical rebrightening
  39. GRB 260619A: SVOM/VT optical counterpart confirmation
  40. GRB 260618B: SVOM/VT optical candidate
  41. GRB 260618B: SVOM/VT optical candidate (duplicate Submission of 45001)
  42. GRB 260619A: SVOM/COLIBRÍ (FM-GFT) optical counterpart candidate
  43. GRB 260616B: AstroSat CZTI detection
  44. GRB 260616A: AstroSat CZTI detection
  45. GRB 260616A: SVOM/GRM observation
  46. EP260618a: OHP/T193 optical observations
  47. GRB 260610B/AT2026owq: 1.3m DFOT optical rebrightening detection
  48. EP260618a: EP-FXT follow-up observation
  49. EP260618a: LCO optical counterpart confirmation
  50. GRB 260617A: CALET Gamma-Ray Burst Monitor detection
  51. EP260618a: COLIBRÍ optical counterpart candidate
  52. GRB 260616A: NuSTAR detection of prompt emission
  53. GRB 260614B: NuSTAR detection of prompt emission
  54. GRB 260619A: SVOM possible detection of a faint burst
  55. IceCube-260610A: Upper limits from a search for additional neutrino events in IceCube
  56. GRB 260618B: Fermi-LAT detection
  57. GRB 260610B/AT 2026owq: FTW optical and NIR observations
  58. GRB 260616A: Insight-HXMT detection
  59. GRB 260618B: Fermi GBM Final Real-time Localization
  60. EP260618a: EP-WXT detection of an X-ray transient
  61. GRB 260610B: AbAO optical observations
  62. GRB 260506B: cubesat Avion detection
  63. GRB 260616C: GECAM-B observation of a burst
  64. GRB 260618A: Fermi GBM Final Real-time Localization
  65. GRB 260617A: Fermi GBM Detection
  66. GRB 260616A: Fermi GBM Observation
  67. GRB 260617A: Fermi GBM Final Real-time Localization
  68. GRB 260616B: CALET Gamma-Ray Burst Monitor detection
  69. EP260616a/GRB260616B: COLIBRÍ optical upper limit
  70. GRB 260616A: GECAM-B observation
  71. GRB 260610B / AT2026owq: SAO RAS optical observations of possible re-brightening
  72. GRB 260429A: cubesat Avion detection
  73. GRB260616C: MAXI/GSC detection
  74. GRB 260616A: Fermi-LAT detection
  75. GRB 260610B / AT 2026owq: COLIBRÍ further observations and confirmation of the rebrigthening
  76. GRB 260614A: AstroSat CZTI detection
  77. EP260616a: EP-WXT detection of a fast X-ray transient
  78. The EP-WXT trigger 01709270148 is likely a flaring star
  79. GRB 260616B: Fermi GBM Detection
  80. GRB 260604C: GRANDMA late observations with CFHT/MegaCam
  81. GRB 260616B: BALROG localization (Fermi Trigger 803286321 / GRB 260616295)
  82. The EP-WXT trigger 01709269893 is likely a flaring star
  83. GRB 260616A: BALROG localization (Fermi Trigger 803272919 / GRB 260616140)
  84. GRB 260616A: Fermi GBM Final Real-time Localization
  85. GRB 260614B: SVOM/ECLAIRs refined analysis
  86. GRB 260610B: Terskol optical observations
  87. GRB 260614B: GECAM-B observation
  88. GRB 260610B: SVOM/GRM observation
  89. GRB 260614B: SVOM/VT optical afterglow confirmation
  90. GRB 260614B: Fermi GBM Observation
  91. GRB 260610B: ALMA detection
  92. GRB 260614A: GECAM-B observation
  93. GRB 260614B: SVOM/VT optical candidate from VHF data
  94. GRB 260614B: SVOM detection of a burst
  95. GRB 260614B: Fermi GBM Final Real-time Localization
  96. GRB 260611B: SVOM/GRM detection
  97. GRB 260614A: Fermi GBM Final Localization
  98. The EP-WXT trigger 01709269488 is likely a flaring star
  99. GRB 260603C: AstroSat CZTI detection
  100. GRB 260610B: further Liverpool Telescope optical observations

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