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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"

27028 results found.

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

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