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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"

36194 results found.

  1. GRB 261101B: BALROG localization (Fermi Trigger 815240277 / GRB 261101651)
  2. GRB 261101B: Fermi GBM Final Real-time Localization
  3. GRB 261101A: Fermi GBM Final Real-time Localization
  4. GRB 261030A: Fermi GBM Detection
  5. Fermi GRB 261030B: Global MASTER-Net observations report
  6. GRB 261030B: Fermi GBM Final Real-time Localization
  7. GRB 261029A: SVOM/ECLAIRs refined analysis
  8. The EP-WXT trigger 01709321980: KAIT confirmation of a stellar flare
  9. GRB 261030A: BALROG localization (Fermi Trigger 815070447 / GRB 261030686)
  10. GRB 261030A: Fermi GBM Final Real-time Localization
  11. GRB 261029A / AT 2026ahaw: Optical upper limits from the PKU 60cm Telescope
  12. GRB 261029A: Glowbug gamma-ray detection
  13. GRB 261024D: SVOM/GRM observation
  14. GRB 261026A: Mondy, SAO RAS and Terskol optical observations
  15. GRB 261029A : SVOM/GWAC-F60 observations
  16. GRB 261029A: GECAM-B detection of a bright burst
  17. GRB 261029A: WFST optical observations
  18. GRB 261029A: ULL-ASTRO-MASTER observations with LCO 1-m telescope at Siding Spring Observatory
  19. GRB 261029A: Ondrejov D50 optical observations, possible rebrightening
  20. GRB 261029A: Liverpool Telescope observations
  21. GRB 261029A: NuSTAR detection of bright prompt emission
  22. GRB 261029A: Optical detection with 60cm Panzhihua Telescope
  23. GRB 261029A: Fermi GBM Observation
  24. GRB 261029A: FRAM-ORM and FRAM-Auger optical afterglow light curve
  25. GRB 261029A: SVOM/GRM observation of a bright burst
  26. GRB 261029A: CALET Gamma-Ray Burst Monitor detection
  27. IPN triangulation of GRB 261024D
  28. GRB261029A: Infrared fading detected with MDM/MIRAGE
  29. GRB 261029A: SVOM/VT optical observation
  30. GRB 261029B : AstroSat CZTI detection
  31. GRB 261029A / AT2026ahaw: r- and i-band optical follow-up with the PKU 60cm Telescope
  32. GRB 261029A : AstroSat CZTI detection
  33. GRB 261029A: SVOM/C-GFT optical observations
  34. GRB 261029A: EP-FXT follow-up observation
  35. GRB 261029A: Fermi-LAT detection
  36. GRB 261029A: LCO optical observations (correction to GCN 46082)
  37. GRB 261029A: SVOM/COLIBRÍ (FM-GFT) optical observations
  38. GRB 261029A: LCO optical observations
  39. GRB 261029A: NOT imaging and spectroscopic redshift z = 3.27
  40. GRB261029A: Early infrared detection with MDM/MIRAGE
  41. GRB 261029A: KAIT optical observations
  42. GRB 261029A: TRT optical observations
  43. GRB 261029B: Fermi GBM Final Real-time Localization
  44. GRB 261028B / MAXI J1609-487: MAXI GSC detection
  45. GRB 261029A: GOTO optical counterpart candidate
  46. GRB 261029A: SVOM detection of a burst
  47. GRB 261029A: Fermi GBM Final Real-time Localization
  48. GRB 261021A: Glowbug gamma-ray detection
  49. GRB 261028A: Fermi GBM Final Localization
  50. GRB 261026A: SVOM/ECLAIRs refined analysis
  51. GRB 261024C: GECAM-B observation
  52. GRB 261026B: AstroSat CZTI detection
  53. GRB 261024D: Insight-HXMT/HE detection
  54. GRB261026A: Infrared detection with MDM/MIRAGE
  55. GRB 261026A: SVOM/VT optical blue bump
  56. GRB 261026A: SAO RAS optical observations
  57. GRB 261024D: GECAM-B observation
  58. GRB 261026A: EP-FXT follow-up observation
  59. GRB 261024A: SVOM/GRM observation
  60. GRB 261026A: Upper Limit with 60cm Panzhihua Telescope
  61. GRB 261026A: OHP/T120 optical imaging
  62. GRB 261024D: Glowbug gamma-ray detection
  63. GRB 261026B: NuSTAR detection of prompt emission
  64. GRB 261024D: NuSTAR detection of prompt emission
  65. GRB 261024C: NuSTAR detection of prompt emission
  66. GRB 261026A: Ondrejov D50 optical limit
  67. GRB 261026A: ULL-ASTRO-MASTER optical detection with LCO 40-cm telescope at Haleakalā Observatory
  68. GRB 261026A: J-band observations by the SYSU 80cm infrared telescope
  69. GRB 261026A: SVOM/VT optical observations
  70. IPN triangulation of GRB 260730B
  71. GRB 261026C: Fermi GBM Final Real-time Localization
  72. GRB 261020A: Insight-HXMT/HE detection
  73. GRB 261026A: WINTER J-band observations
  74. GRB 261024D: AstroSat CZTI detection of a long burst
  75. GRB 261024C: AstroSat CZTI detection of a long burst
  76. GRB 261019A: GECAM-B observation
  77. GRB 261019A: SVOM/GRM observation
  78. Fermi GRB 261026B: Global MASTER-Net observations report
  79. GRB 261026A: SVOM/VT optical observation from VHF data
  80. GRB 261026A: KAIT optical observations
  81. GRB 261026A: SVOM/COLIBRÍ (FM-GFT) optical observations
  82. GRB 261026B: Fermi GBM Final Real-time Localization
  83. GRB 261024A: NuSTAR detection of prompt emission
  84. GRB 261026A: SVOM detection of a burst
  85. GRB 261025B: Fermi GBM Final Real-time Localization
  86. GRB 261025A: Fermi GBM Final Localization Correction
  87. GRB 261024B: Fermi GBM Final Real-time Localization
  88. GRB 261024A: BALROG localization (Fermi Trigger 814551785 / GRB 261024683)
  89. GRB 261024A: Fermi GBM Final Real-time Localization
  90. EP261023a: Mondy optical upper limit
  91. EP261015a: VLA non-detection
  92. GRB 261019A: Insight-HXMT/HE detection
  93. GRB 261017A: SVOM/GRM observation
  94. GRB 261021A: Fermi GBM Final Real-time Localization
  95. GRB 261020B: AstroSat CZTI detection of a short burst
  96. EP261015a: AZT-20 Assy-Turgen optical observations
  97. GRB 261020A: Fermi GBM Observation
  98. GRB 261017A: SAO RAS optical upper limit
  99. GRB 260903A
  100. EP261015a: Terskol Zeiss-2000 optical upper limit

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