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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

32514 results found.

  1. Fermi GBM Detection of GRB 260919A / EP260920a
  2. IceCube-260930A: Upper limits from a search for additional neutrino events in IceCube
  3. IPN triangulation of GRB 260919A / EP260920a
  4. Fermi GRB 260930B: Global MASTER-Net observations report
  5. GRB 260926C: SVOM/GRM observation
  6. IceCube-260930A - IceCube observation of a high-energy neutrino candidate track-like event
  7. EP260927a: SVOM/ECLAIRs Upper Limit
  8. GRB 260926C: AstroSat CZTI detection
  9. GRB 260926C: GECAM-B observation
  10. GRB 260926A: GECAM-B observation
  11. EP260927a: Global MASTER-Net observations report
  12. GRB 260926B: Glowbug gamma-ray detection of a likely short burst
  13. GRB 260926A: Glowbug gamma-ray detection
  14. GRB 260924A: VLA detection
  15. GRB 260924A: Swift/UVOT UV grism spectrum results
  16. GRB 260924A: AbAO optical observations
  17. Fermi GRB 260928A: Global MASTER-Net observations report
  18. EP260924a: Global MASTER-Net observations report
  19. GRB 260925A: Swift-BAT refined analysis
  20. Swift Trigger 1513439: consistent with noise and not astrophysical
  21. GRB 260924A: Upper limits from a neutrino search with IceCube
  22. Fermi GRB 260926C: Global MASTER-Net observations report
  23. GRB260914A: MAO/AZT-22 optical observations
  24. Fermi GRB 260926A: Global MASTER-Net observations report
  25. GRB 260924A: Near-infrared detection with MDM/MIRAGE
  26. GRB 260924A: COLIBRÍ optical observations
  27. GRB 260924A: Second-epoch J-band upper limit from the SYSU 80 cm infrared telescope
  28. EP260924a: J-band upper limit by SYSU 80cm infrared telescope
  29. GRB 260925A: J-band upper limit by SYSU 80cm infrared telescope
  30. EP260924a: EP-FXT follow-up observation
  31. GRB 260925A: Swift/UVOT Upper Limits
  32. Konus-Wind detection of GRB 260924A
  33. GRB 260924A: Extreme Isotropic-equivalent Gamma-ray Energy and encouragement for multiwavelength follow-up observations
  34. GRB 260923A: Glowbug gamma-ray detection
  35. GRB 260924A: Optical follow-up observations with Kinder
  36. GRB 260922A: Glowbug gamma-ray detection
  37. GRB 260925A: COLIBRÍ optical upper limits
  38. GRB 260925A: FRAM-Auger optical limit
  39. GRB 260924A: Ondrejov D50 optical afterglow detection
  40. EP260924a: J-band upper limit with WINTER
  41. GRB 260924A: SVOM/GRM observation
  42. GRB 260924A: 2.2m CAHA spectroscopic redshift z = 3.51
  43. GRB 260923A: Insight-HXMT/HE detection
  44. GRB 260924A: J-band observations by the SYSU 80 cm infrared telescope
  45. GRB 260924A: Swift/UVOT Detection
  46. GRB 260924A: GROWTH-India Telescope optical observations
  47. GRB 260924A: Swift-BAT refined analysis
  48. GRB 260924A: NuSTAR detection of prompt emission
  49. Konus-Wind detection of GRB 260922A
  50. GRB 260922A: NuSTAR detection of prompt emission
  51. GRB 260921A: NuSTAR detection of prompt emission
  52. Konus-Wind detection of GRB 260921A (correction to GCN 45722)
  53. GRB 260921A: SVOM/GRM observation
  54. GRB 260922A: COLIBRÍ Confirmation of the Optical Counterpart
  55. GRB 260924A: Fermi GRB Observation
  56. Konus-Wind detection of GRB 260921A (possible merger-origin)
  57. GRB 260924A: Fermi-LAT detection of a bright burst
  58. GRB 260924A: AstroSat CZTI detection
  59. GRB 260920A: SVOM/GRM observation
  60. GRB 260924A: NOT optical counterpart confirmation
  61. GRB 260924A: detection of a bright optical afterglow by the 1.5m OSN telescope
  62. GRB 260922A: CALET Gamma-Ray Burst Monitor detection
  63. Fermi GRB 260923A: Global MASTER-Net observations report
  64. Trigger_21914: Swift ToO observations
  65. EP260806a: e-MERLIN detection at 5 GHz
  66. GRB 260922A: Ondrejov D50 optical limit
  67. Fermi-LAT Gamma-ray Observations of IceCube-260919A
  68. Fermi-LAT Gamma-ray Observations of IceCube-260916A
  69. ATCA observations of GRB 260909A
  70. GRB 260922A: Swift-BAT refined analysis
  71. EP260920a: VLT/HAWK-I near-infrared counterpart confirmation
  72. GRB 260922A: J-band upper limit with WINTER
  73. GRB 260922A: Swift/UVOT Upper Limits
  74. GRB 260922A: COLIBRÍ Optical Counterpart Candidate (correction to GCN 45698)
  75. GRB 260922A: COLIBRÍ optical upper limits
  76. Fermi-LAT Gamma-ray Observations of IceCube-260805A
  77. Konus-Wind detection of GRB 260810A
  78. GRB 260920A: Glowbug gamma-ray detection
  79. GRB 260918A: SVOM/ECLAIRs refined analysis
  80. GRB 260922A: SVOM/C-GFT optical upper limit
  81. GRB 260917C: AstroSat CZTI detection
  82. GRB 260920B/EP260920b: GECAM-B detection of a burst
  83. GRB 260921A: AstroSat CZTI detection
  84. GRB 260921A: Swift-BAT refined analysis
  85. GRB 260921A: Fermi GBM Observation
  86. EP260920b: 2.2m CAHA optical afterglow detection and 10.4m GTC redshift confirmation
  87. GRB 260917B:: SVOM/ECLAIRs refined analysis
  88. EP260920a: VLT/HAWK-I near-infrared candidate
  89. Swift GRB 260921A: Global MASTER-Net observations report
  90. EP260920b: VLT/X-shooter spectroscopic redshift z = 3.582
  91. EP260920b: LCO observations
  92. GRB 260920A: AstroSat CZTI detection
  93. EP260920b: SVOM/VT optical observation
  94. EP260920b: refined analysis of the EP-WXT and EP-FXT observations
  95. EP260920b: COLIBRÍ optical observations
  96. EP260920b: LCO optical counterpart detection
  97. EP260920b: Global MASTER-Net observations report
  98. IceCube-260919A: Upper limits from a search for additional neutrino events in IceCube
  99. EP260920a: NOT early time optical upper limits
  100. EP260920a: NOT optical upper limits

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