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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"

28234 results found.

  1. EP261023a: J band upper limit by SYSU 80cm infrared telescope
  2. EP261015a: VST optical observations
  3. GRB 261024A: BALROG localization (Fermi Trigger 814551785 / GRB 261024683)
  4. EP261023a: Mondy optical upper limit
  5. EP261015a: MAO/AZT-22 optical observations
  6. EP261015a: VLA non-detection
  7. EP261023a: NOT optical counterpart candidate
  8. EP261023a: Einstein Probe detection of an X-ray transient
  9. The EP-WXT trigger 01709321472 is likely a flaring star
  10. IceCube-261020A: Upper limits from a search for additional neutrino events in IceCube
  11. NuSTAR 261020, a 830s hard X-ray transient
  12. EP261015a: GSP multiband optical follow-up observations
  13. GRB 261017A: SVOM/GRM observation
  14. EP261015a: Further optical observations with the 1.3m DFOT
  15. GRB 261020B: AstroSat CZTI detection of a short burst
  16. Fermi-LAT Gamma-ray Observations of IceCube-261020A
  17. EP261015a: AZT-20 Assy-Turgen optical observations
  18. GRB 261020A: Fermi GBM Observation
  19. GRB 261017A: SAO RAS optical upper limit
  20. GRB 260903A
  21. EP261015a: Follow-up with the 1.3m DFOT
  22. EP261015a: Terskol Zeiss-2000 optical upper limit
  23. EP261007b: Further EP-FXT follow-up observations
  24. GRB 261017A: COLIBRÍ optical upper limit
  25. GRB 261020A: MAXI GSC detection
  26. EP261015a: COLIBRÍ optical observations of a rebrightening
  27. GRB 261017A: Possible Swift/UVOT Detection
  28. GRB 261017A: Luminance-band upper limit from a 28cm telescope in Chengde
  29. GRB 261017A: R-band upper limit with the 1.3-m DFOT
  30. GRB 261017A: Swift-BAT refined analysis
  31. EP261015b: NOT Optical Observations
  32. GRB 261017A: J band upper limit by the SYSU 80cm infrared telescope
  33. EP261015c: refined analysis of the EP-FXT observation favors a stellar flare interpretation
  34. GRB 261017A : MITSuME Akeno optical upper limits
  35. GRB 261017A: Swift-XRT refined Analysis
  36. GRB 261017A: Nanshan/NEXT optical upper limit
  37. GRB 261017A: Enhanced Swift-XRT position
  38. GRB 261017A: Fermi GBM Observation
  39. GRB 261017A: Swift detection of a burst
  40. EP261015a: Tentative fading of the candidate optical counterpart from the NOT
  41. EP261015b: Refined analysis of EP-FXT observations
  42. EP261015b: J-band upper limit by the SYSU 80cm infrared telescope
  43. EP261015a: refined analysis of EP-FXT observations
  44. EP261015c: J-band upper limit with WINTER
  45. EP261015a: J-band upper limit with WINTER
  46. EP261006a / AT 2026aetp: Optical follow-up with the 1.3-m DFOT
  47. GRB 261011A: 1.3m DFOT optical upper limit
  48. GRB 261010A: Pan-STARRS z-band imaging and upper limit
  49. EP261015a: SVOM/VT optical observation
  50. GRB 261010A: VLA radio observations
  51. EP261015a: COLIBRÍ optical observations
  52. EP261015c: Einstein Probe detection of a fast X-ray transient
  53. EP261015b: Einstein Probe detection of an X-ray transient
  54. EP261015a: Einstein Probe detection of a fast X-ray transient
  55. EP261015a (WXT 11900947714): Possible optical counterpart from NOT and LCO
  56. GRB 261010A: LBT tentative near-infrared detection
  57. GRB 261011A: SAO RAS and AbAO optical observations
  58. GRB 261010A: Glowbug gamma-ray detection
  59. GRB 261008A: SVOM/GRM observation
  60. GRB 261009A: GECAM-B detection of a burst
  61. EP261006a : MeerKAT radio observations.
  62. IceCube-261012A: Upper limits from a search for additional neutrino events in IceCube
  63. GRB 261010A: a short minimum variability timescale and a distinct pulse evolution compatible with a merger origin
  64. Fermi-LAT Gamma-ray Observations of IceCube-261012A
  65. GRB 261010A: J-band upper limit by the SYSU 80cm infrared telescope
  66. GRB 261010A: Swift-XRT refined Analysis
  67. GRB 261011A: Swift-XRT refined Analysis
  68. GRB 261011A: Enhanced Swift-XRT position
  69. GRB 261010A: a Type I-L (merger-driven) GRB candidate
  70. GRB 261011A: Swift-BAT refined analysis
  71. GRB 261010A: 10.4m GTC spectroscopy of the galaxy 2" from the afterglow
  72. MAXI GRB261012.23: Global MASTER-Net observations report
  73. GRB 261011A: REM optical/NIR observations
  74. GRB 261011A: SOAR optical afterglow observations at ~17 hours
  75. EP261006a: 10 GHz VLA observations
  76. GRB 261011A: VLT/X-shooter redshift constraints
  77. GRB 261012A: MAXI GSC detection
  78. GRB 261010A: Swift-BAT refined analysis
  79. GRB 261011A : MITSuME Akeno optical afterglow candidate detection
  80. GRB 261011A: Optical followup from Sichuan South Observatory
  81. GRB 261011A: GMG Optical Observation
  82. GRB 261011A: Liverpool Telescope optical observations
  83. GRB 261011A: J-band observations by the SYSU 80cm infrared telescope
  84. GRB 261010A: NOT confirmation of the optical afterglow
  85. GRB 261010A: Fermi GBM Observation
  86. GRB 261011A: continued LCO optical observations
  87. EP261007b: Global MASTER-Net observations report
  88. GRB 261011A: GROWTH-India Telescope optical observations
  89. GRB 261011A: Luminance-band upper limit from a 28cm telescope in Chengde
  90. Swift GRB 261011A: Global MASTER-Net observations report
  91. GRB 261011A: Optical follow-up observations with Kinder
  92. GRB 261011A: SVOM/C-GFT optical observations
  93. EP261007b: Second EP-FXT follow-up observation and a possible X-ray counterpart to the optical transient
  94. GRB 261011A: LCO optical observations
  95. GRB 261011A: SVOM/VT optical observation from VHF data
  96. GRB 261011A: LCO optical observations
  97. GRB 261011A: TRT optical afterglow detection
  98. GRB 261011A: Swift detection of an unusual burst
  99. GRB 261011A: SVOM detection of a long bright burst
  100. GRB 261010A: Enhanced Swift-XRT position

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