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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"

32580 results found.

  1. GRB 260924A: Optical follow-up observations with Kinder
  2. GRB 260922A: Glowbug gamma-ray detection
  3. GRB 260925A: COLIBRÍ optical upper limits
  4. GRB 260925A: FRAM-Auger optical limit
  5. GRB 260924A: Ondrejov D50 optical afterglow detection
  6. EP260924a: J-band upper limit with WINTER
  7. GRB 260924A: SVOM/GRM observation
  8. GRB 260924A: 2.2m CAHA spectroscopic redshift z = 3.51
  9. GRB 260923A: Insight-HXMT/HE detection
  10. GRB 260924A: J-band observations by the SYSU 80 cm infrared telescope
  11. GRB 260924A: Swift/UVOT Detection
  12. GRB 260924A: GROWTH-India Telescope optical observations
  13. GRB 260924A: Swift-BAT refined analysis
  14. GRB 260924A: NuSTAR detection of prompt emission
  15. Konus-Wind detection of GRB 260922A
  16. GRB 260922A: NuSTAR detection of prompt emission
  17. GRB 260921A: NuSTAR detection of prompt emission
  18. Konus-Wind detection of GRB 260921A (correction to GCN 45722)
  19. GRB 260921A: SVOM/GRM observation
  20. GRB 260922A: COLIBRÍ Confirmation of the Optical Counterpart
  21. GRB 260924A: Fermi GRB Observation
  22. Konus-Wind detection of GRB 260921A (possible merger-origin)
  23. GRB 260924A: Fermi-LAT detection of a bright burst
  24. GRB 260924A: AstroSat CZTI detection
  25. GRB 260920A: SVOM/GRM observation
  26. GRB 260924A: NOT optical counterpart confirmation
  27. GRB 260924A: detection of a bright optical afterglow by the 1.5m OSN telescope
  28. GRB 260922A: CALET Gamma-Ray Burst Monitor detection
  29. Fermi GRB 260923A: Global MASTER-Net observations report
  30. EP260806a: e-MERLIN detection at 5 GHz
  31. GRB 260922A: Ondrejov D50 optical limit
  32. Fermi-LAT Gamma-ray Observations of IceCube-260919A
  33. Fermi-LAT Gamma-ray Observations of IceCube-260916A
  34. ATCA observations of GRB 260909A
  35. GRB 260922A: Swift-BAT refined analysis
  36. EP260920a: VLT/HAWK-I near-infrared counterpart confirmation
  37. GRB 260922A: J-band upper limit with WINTER
  38. GRB 260922A: Swift/UVOT Upper Limits
  39. GRB 260922A: COLIBRÍ Optical Counterpart Candidate (correction to GCN 45698)
  40. GRB 260922A: COLIBRÍ optical upper limits
  41. Fermi-LAT Gamma-ray Observations of IceCube-260805A
  42. Konus-Wind detection of GRB 260810A
  43. GRB 260920A: Glowbug gamma-ray detection
  44. GRB 260918A: SVOM/ECLAIRs refined analysis
  45. GRB 260922A: SVOM/C-GFT optical upper limit
  46. GRB 260917C: AstroSat CZTI detection
  47. GRB 260920B/EP260920b: GECAM-B detection of a burst
  48. GRB 260921A: AstroSat CZTI detection
  49. GRB 260921A: Swift-BAT refined analysis
  50. GRB 260921A: Fermi GBM Observation
  51. EP260920b: 2.2m CAHA optical afterglow detection and 10.4m GTC redshift confirmation
  52. GRB 260917B:: SVOM/ECLAIRs refined analysis
  53. EP260920a: VLT/HAWK-I near-infrared candidate
  54. Swift GRB 260921A: Global MASTER-Net observations report
  55. EP260920b: VLT/X-shooter spectroscopic redshift z = 3.582
  56. EP260920b: LCO observations
  57. GRB 260920A: AstroSat CZTI detection
  58. EP260920b: SVOM/VT optical observation
  59. EP260920b: refined analysis of the EP-WXT and EP-FXT observations
  60. EP260920b: COLIBRÍ optical observations
  61. EP260920b: LCO optical counterpart detection
  62. EP260920b: Global MASTER-Net observations report
  63. IceCube-260919A: Upper limits from a search for additional neutrino events in IceCube
  64. EP260920a: NOT early time optical upper limits
  65. EP260920a: NOT optical upper limits
  66. EP260920a: SVOM/VT optical upper limits
  67. EP260917a: Global MASTER-Net observations report
  68. EP260920a: refined analysis of the EP-WXT and autonomous EP-FXT observations
  69. EP260920a: COLIBRÍ optical upper limits
  70. EP260920a: Update of the LCO optical counterpart candidate
  71. EP260917b: EP-FXT non-detection and upper limit
  72. EP260920a: LCO optical counterpart candidate
  73. GRB 260915A: VLT optical and near-infrared upper limits
  74. EP260917a: refined analysis of the EP-FXT observations
  75. IceCube-260919A - IceCube observation of a high-energy neutrino candidate track-like event
  76. EP260806a: Yamaguchi Interferometer radio detections
  77. EP260917a: SVOM/VT optical upper limits
  78. GRB 260918A: SVOM/C-GFT optical upper limits
  79. Fermi GBM Sub-Threshold Detection of GRB 260918A
  80. Konus-Wind detection of GRB 260916B (short/hard)
  81. GRB 260918A: SVOM/VT optical upper limits
  82. GRB 260916B: Glowbug gamma-ray detection of a short burst
  83. GRB 260918A: EP-FXT follow-up observation
  84. GRB 260917B: Mondy optical upper limit
  85. IPN triangulation of GRB 260916B (short)
  86. EP260917A: J-band upper limit with WINTER
  87. IPN triangulation of GRB 260810A
  88. GRB 260917B: EP-FXT follow-up observation
  89. EP260917a: COLIBRÍ optical upper limits
  90. GRB 260915A: Swift-XRT afterglow detection
  91. GRB 260918A: LCO optical upper limits
  92. GRB 260918A: SVOM/COLIBRÍ (FM-GFT) optical upper limits
  93. GRB 260918A: SVOM detection of a burst
  94. GRB 260917B: FRAM-Auger optical limits
  95. IceCube-260916A: Upper limits from a search for additional neutrino events in IceCube
  96. GRB 260917A: Glowbug gamma-ray detection
  97. GRB 260915A: SVOM/ECLAIRs refined analysis
  98. GRB 260917B: WINTER J-band observations
  99. GRB 260917B: SVOM/VT optical observations
  100. GRB 260917B: LCO optical observation

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