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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"

45750 results found.

  1. The EP-WXT trigger 01709251871 is likely a flaring star
  2. Fermi GRB 260120C: Global MASTER-Net observations report
  3. GRB 260120B: Swift-BAT refined analysis
  4. GRB 260120B: Swift-XRT refined Analysis
  5. EP260116a: COLIBRÍ further observations
  6. GRB 251122A / EP251122a: VLT/X-shooter host redshift z = 1.765
  7. GRB 260120B: Fermi GBM Observation
  8. EP260105a: GTC/HiPERCAM optical observations
  9. GRB 260120B: Swift/UVOT Detection
  10. GRB 260120B: COLIBRÍ optical upper limits
  11. SVOM GRB260121.06: Global MASTER-Net observations report
  12. GRB 260120B: Enhanced Swift-XRT position
  13. GRB 260120B: SVOM/C-GFT optical counterpart detection
  14. GRB 260120C: Fermi GBM Final Real-time Localization
  15. GRB 260101A: 239Alferov CubeSat detection
  16. EP260116a: COLIBRÍ observations of a tentative optical rebrightening
  17. GRB 260120B: Swift detection of a burst
  18. Swift GRB260120B: Global MASTER-Net observations report
  19. GRB 260120B: Fermi GBM Final Real-time Localization
  20. EP260119A: Mondy I-Band Observations
  21. Fermi trigger No 790601190: Global MASTER-Net observations report
  22. Fermi trigger No 790570272: Global MASTER-Net observations report
  23. GRB 260114A: Swift/UVOT Upper Limits
  24. EP260119a: Liverpool Telescope optical follow-up observations
  25. GRB 251202A: further radio observations with the VLA
  26. Trigger 1442421: Swift detection of HMXB 1A 1118-61
  27. EP260119A: GTC/OSIRIS+ spectroscopic redshift z = 5.47
  28. EP260119a: KAIT optical observations
  29. GRB 260120A: Fermi GBM Final Real-time Localization
  30. EP260119a: SVOM/VT optical observation
  31. EP260119a: update of EP-FXT follow-up observation
  32. EP260119a: NOT optical observations
  33. EP260119a: SAO RAS optical observations
  34. SVOM GRB260119.92: Global MASTER-Net observations report
  35. SVOM GRB260119.92: Global MASTER-Net observations report
  36. SVOM GRB260119.90: Global MASTER-Net observations report
  37. EP260116a: COLIBRÍ detection of a fading optical source
  38. GRB 251208D: SVOM/ECLAIRs refined analysis
  39. GRB 251208D: SVOM/ECLAIRs refined analysis
  40. GRB 260117A: Swift-XRT afterglow detection
  41. EP260119a: COLIBRÍ photometric redshift z ≈ 5.6
  42. EP260119a: Global MASTER-Net observations report
  43. GRB 260115A: AstroSat CZTI detection
  44. EP260119a: LCO optical observations
  45. GRB 260117A: ZTSh optical upper limit
  46. EP260119a: COLIBRÍ optical counterpart candidate
  47. EP260119a: preliminary result from the EP-FXT observation
  48. GRB 260110A: SVOM detection of a burst through offline search
  49. EP260119a: EP-WXT detection of a fast X-ray transient
  50. Swift GRB260118.48: Global MASTER-Net observations report
  51. GRB 260117A: SVOM/COLIBRÍ (FM-GFT) optical observations
  52. SVOM GRB260117.82: Global MASTER-Net observations report
  53. Fermi-LAT Gamma-ray Observations of IceCube-260115A
  54. Swift trigger on the HMXB 1A 1118-61
  55. GRB 260117A: SVOM/VT optical candidate
  56. GRB 260117A: SVOM/C-GFT upper limit
  57. GRB 260117A: Swift-XRT observations
  58. GRB 260117A: Swift ToO observations
  59. GRB 260117A: SVOM detection of a long faint burst
  60. EP 260116a: COLIBRÍ optical upper limit
  61. Swift triggered on the HMXB 1A 1118-61
  62. GRB 260115A: GECAM-B observation
  63. FRB 20251229A: COLIBRÍ further inspection of the updated localization
  64. EP260116a: Liverpool Telescope upper limits
  65. FRB 20251229A: Updated CHIME/FRB Baseband Localization of FRB 20251229A
  66. EP260116A: 1.3m DFOT optical upper limit
  67. GRB 260114A: VLT/MUSE spectroscopic observations
  68. IceCube-260115A: Upper limits from a search for additional neutrino events in IceCube
  69. EP260116a: Global MASTER-Net observations report
  70. GRB 260111A: COLIBRÍ fading of the optical counterpart candidate
  71. EP260116a: Xinglong optical upper limit
  72. EP260116a: Einstein Probe detection of an X-ray transient
  73. GRB 260114A: VLT/HAWK-I further near-infrared upper limits
  74. IceCube Alert 260115.73: Global MASTER-Net observations report
  75. IceCube-260115A - IceCube observation of a high-energy neutrino candidate track-like event
  76. GRB 260115A: BALROG localization (Fermi Trigger 790192010 / GRB 260115741)
  77. IceCube: GCN Notices for high-energy track alerts now streamed via Kafka
  78. Fermi GRB 260115A: Global MASTER-Net observations report
  79. GRB 260115A: Fermi GBM Final Real-time Localization
  80. GRB260114A: STEP/T80S optical limits
  81. GRB 251222A: radio detection with the VLA
  82. GRB 260114A: VLT/HAWK-I near-infrared upper limits
  83. Konus-Wind detection of GRB 260114A
  84. GRB 260114A: Swift-XRT refined Analysis
  85. GRB 260114A: 6 GHz VLA observations
  86. GRB 260114A: VLT/X-shooter redshift of the putative host galaxy
  87. GRB 260114A : MITSuME Akeno optical upper limits
  88. GRB 260114A: COLIBRÍ optical upper limits
  89. GRB 260114A: TNG NIR upper limit
  90. GRB 260114A: NOT optical observations
  91. Konus-Wind detection of GRB 251230A / EP251230a
  92. GRB 260114A: SVOM/GRM observation of a short burst
  93. Swift GRB 260114A: Global MASTER-Net observations report
  94. GRB 260114A: GECAM-B observation of a short burst
  95. GRB 260114A: Mondy optical observations
  96. GRB 260114A: Fermi GBM observation
  97. GRB 260112B: GECAM-B observation
  98. GRB 260114A: GMG Optical Observation
  99. Fermi-LAT Gamma-ray Observations of IceCube-260111A
  100. GRB 260114A: Swift detection of a short burst

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