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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"

28262 results found.

  1. GRB261026A: Infrared detection with MDM/MIRAGE
  2. GRB 261026A: SAO RAS optical observations
  3. EP Alert 261026.29: Global MASTER-Net observations report
  4. GRB 261026A: EP-FXT follow-up observation
  5. GRB 261024A: SVOM/GRM observation
  6. GRB 261026A: Upper Limit with 60cm Panzhihua Telescope
  7. EP 261025a: J-band upper limit with MIRAGE
  8. GRB 261024D: Glowbug gamma-ray detection
  9. GRB 261026B: NuSTAR detection of prompt emission
  10. GRB 261024D: NuSTAR detection of prompt emission
  11. GRB 261024C: NuSTAR detection of prompt emission
  12. GRB 261026A: Ondrejov D50 optical limit
  13. GRB 261026A: ULL-ASTRO-MASTER optical detection with LCO 40-cm telescope at Haleakalā Observatory
  14. GRB 261026A: J-band observations by the SYSU 80cm infrared telescope
  15. SVOM GRB261026.26: Global MASTER-Net observations report
  16. GRB 261026A: WINTER J-band observations
  17. GRB 261019A: SVOM/GRM observation
  18. Fermi GRB 261026B: Global MASTER-Net observations report
  19. GRB 261026A: SVOM/VT optical observation from VHF data
  20. GRB 261026A: KAIT optical observations
  21. GRB 261026A: SVOM/COLIBRÍ (FM-GFT) optical observations
  22. GRB 261024A: NuSTAR detection of prompt emission
  23. GRB 261026A: SVOM detection of a burst
  24. EP261025a: J-band upper limit with WINTER
  25. EP261023a: J-band upper limit with WINTER
  26. EP 261025a: COLIBRÍ optical upper limit
  27. EP261025a: Einstein Probe detection of a fast X-ray transient
  28. EP261023a: J band upper limit by SYSU 80cm infrared telescope
  29. EP261015a: VST optical observations
  30. GRB 261024A: BALROG localization (Fermi Trigger 814551785 / GRB 261024683)
  31. EP261023a: Mondy optical upper limit
  32. EP261015a: MAO/AZT-22 optical observations
  33. EP261015a: VLA non-detection
  34. EP261023a: NOT optical counterpart candidate
  35. EP261023a: Einstein Probe detection of an X-ray transient
  36. The EP-WXT trigger 01709321472 is likely a flaring star
  37. IceCube-261020A: Upper limits from a search for additional neutrino events in IceCube
  38. NuSTAR 261020, a 830s hard X-ray transient
  39. EP261015a: GSP multiband optical follow-up observations
  40. GRB 261017A: SVOM/GRM observation
  41. EP261015a: Further optical observations with the 1.3m DFOT
  42. GRB 261020B: AstroSat CZTI detection of a short burst
  43. Fermi-LAT Gamma-ray Observations of IceCube-261020A
  44. EP261015a: AZT-20 Assy-Turgen optical observations
  45. GRB 261020A: Fermi GBM Observation
  46. GRB 261017A: SAO RAS optical upper limit
  47. GRB 260903A
  48. EP261015a: Follow-up with the 1.3m DFOT
  49. EP261015a: Terskol Zeiss-2000 optical upper limit
  50. EP261007b: Further EP-FXT follow-up observations
  51. GRB 261017A: COLIBRÍ optical upper limit
  52. GRB 261020A: MAXI GSC detection
  53. EP261015a: COLIBRÍ optical observations of a rebrightening
  54. GRB 261017A: Possible Swift/UVOT Detection
  55. GRB 261017A: Luminance-band upper limit from a 28cm telescope in Chengde
  56. GRB 261017A: R-band upper limit with the 1.3-m DFOT
  57. GRB 261017A: Swift-BAT refined analysis
  58. EP261015b: NOT Optical Observations
  59. GRB 261017A: J band upper limit by the SYSU 80cm infrared telescope
  60. EP261015c: refined analysis of the EP-FXT observation favors a stellar flare interpretation
  61. GRB 261017A : MITSuME Akeno optical upper limits
  62. GRB 261017A: Swift-XRT refined Analysis
  63. GRB 261017A: Nanshan/NEXT optical upper limit
  64. GRB 261017A: Enhanced Swift-XRT position
  65. GRB 261017A: Fermi GBM Observation
  66. GRB 261017A: Swift detection of a burst
  67. EP261015a: Tentative fading of the candidate optical counterpart from the NOT
  68. EP261015b: Refined analysis of EP-FXT observations
  69. EP261015b: J-band upper limit by the SYSU 80cm infrared telescope
  70. EP261015a: refined analysis of EP-FXT observations
  71. EP261015c: J-band upper limit with WINTER
  72. EP261015a: J-band upper limit with WINTER
  73. EP261006a / AT 2026aetp: Optical follow-up with the 1.3-m DFOT
  74. GRB 261011A: 1.3m DFOT optical upper limit
  75. GRB 261010A: Pan-STARRS z-band imaging and upper limit
  76. EP261015a: SVOM/VT optical observation
  77. GRB 261010A: VLA radio observations
  78. EP261015a: COLIBRÍ optical observations
  79. EP261015c: Einstein Probe detection of a fast X-ray transient
  80. EP261015b: Einstein Probe detection of an X-ray transient
  81. EP261015a: Einstein Probe detection of a fast X-ray transient
  82. EP261015a (WXT 11900947714): Possible optical counterpart from NOT and LCO
  83. GRB 261010A: LBT tentative near-infrared detection
  84. GRB 261011A: SAO RAS and AbAO optical observations
  85. GRB 261010A: Glowbug gamma-ray detection
  86. GRB 261008A: SVOM/GRM observation
  87. GRB 261009A: GECAM-B detection of a burst
  88. EP261006a : MeerKAT radio observations.
  89. IceCube-261012A: Upper limits from a search for additional neutrino events in IceCube
  90. GRB 261010A: a short minimum variability timescale and a distinct pulse evolution compatible with a merger origin
  91. Fermi-LAT Gamma-ray Observations of IceCube-261012A
  92. GRB 261010A: J-band upper limit by the SYSU 80cm infrared telescope
  93. GRB 261010A: Swift-XRT refined Analysis
  94. GRB 261011A: Swift-XRT refined Analysis
  95. GRB 261011A: Enhanced Swift-XRT position
  96. GRB 261010A: a Type I-L (merger-driven) GRB candidate
  97. GRB 261011A: Swift-BAT refined analysis
  98. GRB 261010A: 10.4m GTC spectroscopy of the galaxy 2" from the afterglow
  99. MAXI GRB261012.23: Global MASTER-Net observations report
  100. GRB 261011A: REM optical/NIR observations

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