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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').
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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"

27029 results found.

  1. Konus-Wind detection of GRB 261011A
  2. Konus-Wind detection of GRB 261007A/EP261007a
  3. GRB 261011A: SOAR optical afterglow observations at ~17 hours
  4. EP261006a: 10 GHz VLA observations
  5. GRB 261012A: MAXI GSC detection
  6. GRB 261011A : MITSuME Akeno optical afterglow candidate detection
  7. GRB 261011A: Optical followup from Sichuan South Observatory
  8. GRB 261011A: GMG Optical Observation
  9. GRB 261011A: J-band observations by the SYSU 80cm infrared telescope
  10. GRB 261010A: NOT confirmation of the optical afterglow
  11. GRB 261010A: Fermi GBM Observation
  12. GRB 261011B: Fermi GBM Final Localization
  13. GRB 261011A: continued LCO optical observations
  14. GRB 261011A: GROWTH-India Telescope optical observations
  15. GRB 261011A: Luminance-band upper limit from a 28cm telescope in Chengde
  16. GRB 261011A: Optical follow-up observations with Kinder
  17. GRB 261011A: SVOM/C-GFT optical observations
  18. EP261007b: Second EP-FXT follow-up observation and a possible X-ray counterpart to the optical transient
  19. GRB 261011A: LCO optical observations
  20. GRB 261011A: SVOM/VT optical observation from VHF data
  21. GRB 261011A: TRT optical afterglow detection
  22. GRB 261011A: GOTO optical counterpart detection
  23. GRB 261011A: Swift detection of an unusual burst
  24. GRB 261011A: SVOM detection of a long bright burst
  25. GRB 261010A: Enhanced Swift-XRT position
  26. EP261010a: refined analysis of the EP-WXT and autonomous EP-FXT observations
  27. GRB 261010A: possible optical afterglow detected with the 1.5m OSN
  28. GRB 261010A: Swift detection of a burst
  29. GRB 261010A: Fermi GBM Final Real-time Localization
  30. EP261006a: Kilonova-Catcher optical follow-up and detection
  31. GRB 261001A: SVOM/GRM observation
  32. EP261010a: SVOM/VT optical upper limits
  33. EP261010a: NOT optical upper limits
  34. EP261010a Einstein Probe detection of an X-ray transient
  35. GRB 261009A: Fermi GBM Final Real-time Localization
  36. EP261007b: SVOM/ECLAIRs Upper Limit
  37. GRB 261008A: GECAM-B observation
  38. EP261006a: Optical follow-up observations with MATCH
  39. EP261007b: J-band upper limit by SYSU 80cm infrared telescope
  40. EP261007b: Refined analysis of the EP-WXT and autonomous EP-FXT observations
  41. GRB 261007A: SVOM/ECLAIRs refined analysis
  42. EP261007b: SVOM/VT optical detection of the NOT transient
  43. GRB 261007A / EP261007a: SVOM/GWAC-F60A/B observations
  44. EP261006a / AT 2026aetp: VLT/X-shooter spectroscopic redshift z = 0.1853
  45. GRB 261007A: Glowbug gamma-ray detection
  46. GRB 261008A: Fermi GBM Final Real-time Localization
  47. EP261007b: NOT optical observations, variable source outside the FXT region
  48. GRB 261007A: SVOM/GRM observation
  49. EP261007b: SVOM/C-GFT optical upper limits
  50. EP261007b: J-band upper limit with WINTER
  51. The EP-WXT trigger 01709321008/EP261007b：Xinglong optical upper limit
  52. GRB 261007A / EP261007a: AstroSat CZTI detection
  53. GRB 261005A: GECAM-B observation
  54. EP261006a: Swift/XRT detection of the fading X-ray counterpart
  55. EP261007a/GRB 261007A：Xinglong optical observation
  56. GRB 261007A/EP261007a: Optical follow-up observations with Kinder
  57. EP261006a: Optical follow-up observations with Kinder
  58. EP261006a: Early Optical Observations by WFST
  59. GRB 261007A / EP261007a: SVOM/VT optical observations
  60. GRB 261007A: Swift-XRT afterglow detection
  61. EP261007b: SVOM/VT optical upper limits
  62. GRB 261007A: SVOM/COLIBRÍ (FM-GFT) optical observations
  63. EP261007b: Einstein Probe detection of an X-ray transient
  64. GRB 261007A / EP261007a: NuSTAR detection of prompt emission
  65. GRB 261007A / EP261007a: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 40-cm telescope at McDonald Observatory
  66. GRB 261007A: Autonomous identification and follow-up of the counterpart to GRB 261007A by BTSbot with ZTF and P60/SEDM
  67. GRB 261007A: GROWTH-India Telescope optical observations
  68. GRB 261007A / EP261007a: TRT optical observations
  69. GRB 261007A: Swift ToO observations
  70. GRB 261007A: SVOM/C-GFT optical observations
  71. GRB 261007A / EP261007a: LCO optical observations
  72. GRB 261007B: Fermi GBM Final Real-time Localization
  73. EP261006a: NOT spectroscopy of a blue continuum
  74. GRB 261007A: WINTER J-band observations
  75. EP261006a: LT and NOT discovery of an optical counterpart
  76. GRB 261007A: Fermi GBM observation
  77. GRB 261007A / EP261007a: VLT/X-shooter spectroscopic redshift z = 2.101
  78. EP261007a/GRB 261007A: Einstein Probe detection of an X-ray transient
  79. EP261006a: SVOM/VT optical upper limits
  80. EP261006a: Einstein Probe detection of an X-ray transient
  81. GRB 261007A: SVOM detection of a burst
  82. EP trigger 01709320985: SVOM/C-GFT optical upper limits
  83. GRB 261005A: Glowbug gamma-ray detection
  84. GRB 261005B: Swift/UVOT Upper Limits
  85. GRB 261005B: J-band upper limit with WINTER
  86. GRB 261005B: Fermi GBM Observation
  87. GRB 261005B: Enhanced Swift-XRT position
  88. The EP-WXT trigger 01709320908 is likely a flaring star
  89. EP trigger 01709320908: Ondrejov D50 observation, fading star suggests stellar flare
  90. GRB 261005B: Swift detection of a burst
  91. GRB 261005A: Fermi GBM Final Real-time Localization
  92. GRB 261003A: Glowbug gamma-ray detection of a likely short burst
  93. GRB 261002A: Fermi GBM Final Localization
  94. EP#01709320865: Swift-XRT observations
  95. GRB 260930B: SVOM/GRM observation
  96. Konus-Wind detection of GRB 260919A / EP 260920a
  97. GRB 260921B: GECAM-B observation
  98. EP261003a: J-band upper limit with WINTER
  99. EP261003a: refined analysis of the EP-WXT and autonomous EP-FXT observations
  100. GRB 260930B: GECAM-B detection of a burst

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