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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"

32725 results found.

  1. GRB 261026A: SVOM/ECLAIRs refined analysis
  2. GRB 261024C: GECAM-B observation
  3. GRB 261026B: AstroSat CZTI detection
  4. GRB 261024D: Insight-HXMT/HE detection
  5. GRB261026A: Infrared detection with MDM/MIRAGE
  6. GRB 261026A: SVOM/VT optical blue bump
  7. GRB 261026A: SAO RAS optical observations
  8. GRB 261024D: GECAM-B observation
  9. GRB 261026A: EP-FXT follow-up observation
  10. GRB 261024A: SVOM/GRM observation
  11. GRB 261026A: Upper Limit with 60cm Panzhihua Telescope
  12. EP 261025a: J-band upper limit with MIRAGE
  13. GRB 261026A: OHP/T120 optical imaging
  14. GRB 261024D: Glowbug gamma-ray detection
  15. GRB 261026B: NuSTAR detection of prompt emission
  16. GRB 261024D: NuSTAR detection of prompt emission
  17. GRB 261024C: NuSTAR detection of prompt emission
  18. GRB 261026A: Ondrejov D50 optical limit
  19. GRB 261026A: ULL-ASTRO-MASTER optical detection with LCO 40-cm telescope at Haleakalā Observatory
  20. GRB 261026A: J-band observations by the SYSU 80cm infrared telescope
  21. GRB 261026A: SVOM/VT optical observations
  22. IPN triangulation of GRB 260730B
  23. GRB 261020A: Insight-HXMT/HE detection
  24. GRB 261026A: WINTER J-band observations
  25. GRB 261019A: GECAM-B observation
  26. GRB 261019A: SVOM/GRM observation
  27. Fermi GRB 261026B: Global MASTER-Net observations report
  28. GRB 261026A: SVOM/VT optical observation from VHF data
  29. GRB 261026A: KAIT optical observations
  30. GRB 261026A: SVOM/COLIBRÍ (FM-GFT) optical observations
  31. GRB 261024A: NuSTAR detection of prompt emission
  32. GRB 261026A: SVOM detection of a burst
  33. EP261025a: J-band upper limit with WINTER
  34. EP261023a: J-band upper limit with WINTER
  35. EP 261025a: COLIBRÍ optical upper limit
  36. EP261023a: J band upper limit by SYSU 80cm infrared telescope
  37. EP261015a: VST optical observations
  38. EP261023a: Mondy optical upper limit
  39. EP261015a: MAO/AZT-22 optical observations
  40. EP261015a: VLA non-detection
  41. EP261023a: NOT optical counterpart candidate
  42. GRB 261019A: Insight-HXMT/HE detection
  43. IceCube-261020A: Upper limits from a search for additional neutrino events in IceCube
  44. EP261015a: GSP multiband optical follow-up observations
  45. GRB 261017A: SVOM/GRM observation
  46. EP261015a: Further optical observations with the 1.3m DFOT
  47. Fermi-LAT Gamma-ray Observations of IceCube-261020A
  48. EP261015a: AZT-20 Assy-Turgen optical observations
  49. GRB 261020A: Fermi GBM Observation
  50. GRB 261017A: SAO RAS optical upper limit
  51. EP261015a: Wendelstein 43 cm optical observations
  52. EP261015a: Follow-up with the 1.3m DFOT
  53. EP261015a: Terskol Zeiss-2000 optical upper limit
  54. EP261007b: Further EP-FXT follow-up observations
  55. GRB 261017A: COLIBRÍ optical upper limit
  56. IceCube-261020A - IceCube observation of a high-energy neutrino candidate track-like event
  57. EP261015a: COLIBRÍ optical observations of a rebrightening
  58. Konus-Wind detection of GRB 261017A
  59. GRB 261017A: Possible Swift/UVOT Detection
  60. GRB 261017A: Luminance-band upper limit from a 28cm telescope in Chengde
  61. GRB 261017A: R-band upper limit with the 1.3-m DFOT
  62. GRB 261017A: Swift-BAT refined analysis
  63. GRB 261017A: a short minimum variability timescale compatible with a compact object merger origin
  64. EP261015b: NOT Optical Observations
  65. GRB 261017A: J band upper limit by the SYSU 80cm infrared telescope
  66. EP261015c: refined analysis of the EP-FXT observation favors a stellar flare interpretation
  67. GRB 261017A : MITSuME Akeno optical upper limits
  68. GRB 261017A: Nanshan/NEXT optical upper limit
  69. GRB 261017A: Fermi GBM Observation
  70. GRB261010A: Retraction of Keck/MOSFIRE near-IR source
  71. EP261015a: Tentative fading of the candidate optical counterpart from the NOT
  72. EP261015b: Refined analysis of EP-FXT observations
  73. EP261015b: J-band upper limit by the SYSU 80cm infrared telescope
  74. EP261015a: refined analysis of EP-FXT observations
  75. EP261015c: J-band upper limit with WINTER
  76. EP261015a: J-band upper limit with WINTER
  77. EP261006a / AT 2026aetp: Optical follow-up with the 1.3-m DFOT
  78. GRB 261011A: 1.3m DFOT optical upper limit
  79. GRB 261010A: Pan-STARRS z-band imaging and upper limit
  80. EP261015a: SVOM/VT optical observation
  81. GRB 261010A: VLA radio observations
  82. EP261015a: COLIBRÍ optical observations
  83. GRB261010A: Keck/MOSFIRE detection of a near-IR source
  84. EP261015a: Einstein Probe detection of a fast X-ray transient
  85. GRB 261010A: ASKAP non-detection of a radio afterglow
  86. GRB 261010A: LBT tentative near-infrared detection
  87. GRB 261011A: SAO RAS and AbAO optical observations
  88. GRB 261010A: Glowbug gamma-ray detection
  89. GRB 261008A: SVOM/GRM observation
  90. GRB 261009A: GECAM-B detection of a burst
  91. EP261006a : MeerKAT radio observations.
  92. IceCube-261012A: Upper limits from a search for additional neutrino events in IceCube
  93. GRB 261010A: initial pulse rest-frame energetics from Konus-Wind detection
  94. GRB 261010A: a short minimum variability timescale and a distinct pulse evolution compatible with a merger origin
  95. GRB 261011A: Later-epoch J-band upper limit from the SYSU 80 cm infrared telescope
  96. Fermi-LAT Gamma-ray Observations of IceCube-261012A
  97. GRID detection of GRB 261010A
  98. GRB 261011A: GECAM-B observation
  99. GRB 261011B: GECAM-B observation
  100. GRB 261010A: J-band upper limit by the SYSU 80cm infrared telescope

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