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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"

32687 results found.

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

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