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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"

32575 results found.

  1. GRB 251214B: 1.3m DFOT optical detection
  2. EP251214a: Global MASTER-Net observations report
  3. GRB 251214B: Xinglong-2.16m optical observation
  4. GRB 251214B : MASTER optical afterglow detection
  5. GRB 251214B: SVOM/C-GFT optical observations
  6. EP251214a: COLIBRÍ optical upper limit
  7. Swift GRB 251214B: Global MASTER-Net observations report
  8. EP251214a: EP-WXT detection of an X-ray transient possibly associated with GRB 251214A
  9. Fermi GRB 251214A: Global MASTER-Net observations report
  10. EP251212a: Global MASTER-Net observations report
  11. EP251212a: KAIT optical upper limit
  12. EP251212a / GRB 251212A: AstroSat CZTI detection
  13. EP251212a: EP-FXT follow-up observation
  14. GRB 251211B: AstroSat CZTI detection
  15. IceCube-251210A: No Candidate Transients from the Zwicky Transient Facility
  16. GRB 251209A: NuSTAR detection of prompt emission
  17. EP251212a : COLIBRÍ optical upper limit
  18. EP251212a: Einstein Probe detection of an X-ray transient
  19. Fermi-LAT Gamma-ray Observations of IceCube-251210A
  20. IceCube-251210A: Upper limits from a search for additional neutrino events in IceCube
  21. Fermi GRB 251211B: Global MASTER-Net observations report
  22. IceCube-251210A: DDOTI Optical Upper Limit
  23. GRB 251209A: Fermi GBM observation
  24. GRB 251205A: 1.3m DFOT optical upper limit
  25. GRB 251209A: AstroSat CZTI detection
  26. EP251124a: Mondy optical upper limit
  27. GRB 251129A/EP251129a: AbAO and Mondy optical observations
  28. EP251130a: Mondy and AbAO optical observations
  29. GRB 251208A: AstroSat CZTI detection
  30. Fermi GBM Sub-Threshold Detection of GRB 251205A
  31. GRB 251208A: Glowbug gamma-ray detection
  32. GRB 251208B: COLIBRÍ optical upper limits
  33. EP251118a / GRB 251118C: VLT/MUSE redshift confirmation
  34. GRB 251208C: GECAM-B observation of a short burst
  35. GRB 251208A: GECAM-B observation of a short burst
  36. Fermi GRB 251209A: Global MASTER-Net observations report
  37. Fermi GRB 251208C: Global MASTER-Net observations report
  38. GRB 251206A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  39. GRB 251208B: Swift-XRT afterglow detection
  40. GRB 251208D: LAST optical upper limit
  41. GRB 251208D: LCO analysis of the XRT sources
  42. GRB 251208B: Fermi GBM Observation
  43. GRB 251208B: GROWTH-India Telescope optical upper limits
  44. GRB 251205A: J-band detection with WINTER
  45. GRB 251208D: Swift-XRT observations
  46. GRB 251208A: SVOM/GRM observation of a short burst
  47. GRB 251208C: SVOM/GRM observation of a short burst
  48. GRB 251129A: e-MERLIN C-band observations
  49. GRB 251205A: Liverpool Telescope further optical follow-up observations
  50. GRB 251208D: LCO optical upper limits
  51. GRB 251208B: Swift ToO observations
  52. GRB 251208B: Fermi-LAT detection
  53. GRB 251208B: Swift/BAT-GUANO arcminute localization of a burst
  54. GRB 251208D: SVOM possible detection of a faint burst
  55. GRB 251205A : MITSuME Akeno optical afterglow candidate detection
  56. GRB 251205A: FTW optical and NIR observations
  57. EP-WXT trigger 01709249380: KAIT confirmation of a stellar flare
  58. GRB 251205A: Liverpool Telescope further optical follow-up observations
  59. EP-WXT trigger 01709249380: confirmation of a stellar flare by BOOTES-5
  60. GRB 251205A: ZTF and ATLAS optical afterglow detections
  61. GRB 251205A: GROWTH-India Telescope optical observations
  62. GRB 251205A: Swift-BAT refined analysis
  63. GRB 251205A: Swift/UVOT Detection
  64. GRB 251205A: Liverpool Telescope optical follow-up observations
  65. GRB 251203C: Swift/UVOT Upper Limit
  66. Konus-Wind detection of GRB 251118A
  67. GRB 251205A: Zeiss-1000 Koshka observatory optical observations
  68. GRB 251205A: COLIBRÍ optical observations
  69. GRB 251205A: GOTO optical afterglow detection
  70. GRB 251205A: NOT optical observations
  71. GRB 251205A: GTC/OSIRIS+ redshift z = 1.100
  72. Swift GRB 251205A : MASTER OT detection with host galaxy
  73. GRB 251203A: Insight-HXMT/HE detection
  74. GRB 251203C: SVOM/ECLAIRs refined analysis
  75. GRB 251202A / EP251202a: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 40-cm and 1-m telescopes at McDonald Observatory
  76. GRB 251203C: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  77. GRB 251202A: SVOM/GRM observation
  78. GRB 251203A: GECAM-B observation of a burst
  79. GRB 251203A: SVOM/GRM observation
  80. GRB 251201B: SALT spectroscopic redshift z = 1.599
  81. GRB 251203C: J-band observations with WINTER
  82. GRB 251129B: Glowbug gamma-ray detection of a short burst
  83. GRB 251203A: AstroSat CZTI detection
  84. EP251130a: JinShan near-infrared observations
  85. GRB 251203C: LCO optical afterglow confirmation
  86. GRB 251203C: SVOM/VT optical counterpart
  87. GRB 251203C: EP-FXT follow-up observation
  88. GRB 251129A/EP251129a : SVOM/ECLAIRs refined analysis
  89. GRB 251203B: Swift-XRT observations
  90. GRB 251203B: confirmation of a stellar flare by BOOTES-2
  91. GRB 251203B : SVOM trigger sb25120304 is not a GRB
  92. GRB 251203C: LCO optical upper limits
  93. GRB 251203B: LCO optical upper limits
  94. GRB 251203B: SVOM/VT optical observation
  95. GRB 251202A / EP251202a: Liverpool Telescope optical follow-up observations
  96. GRB 251129A / EP251129a: SVOM/VT optical color bluer
  97. GRB 251201B: Insight-HXMT/HE detection
  98. EP251202a / GRB 251202A: Insight-HXMT/HE detection
  99. EP251130a: MAO/AZT-22 optical observations
  100. EP251202a / GRB251202A: AstroSat CZTI detection

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