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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"

42945 results found.

  1. EP260119a: Mondy and SAO RAS optical upper limits
  2. GRB 260122A: Fermi GBM Final Real-time Localization
  3. IceCube-260115A: No Candidate Transients from the Zwicky Transient Facility
  4. EP260119a: Xinglong optical upper limit
  5. The EP-WXT trigger 01709251871 is likely a flaring star
  6. Fermi GRB 260120C: Global MASTER-Net observations report
  7. GRB 260120B: Swift-BAT refined analysis
  8. GRB 260120B: Swift-XRT refined Analysis
  9. EP260116a: COLIBRÍ further observations
  10. GRB 251122A / EP251122a: VLT/X-shooter host redshift z = 1.765
  11. GRB 260120B: Fermi GBM Observation
  12. EP260105a: GTC/HiPERCAM optical observations
  13. GRB 260120B: Swift/UVOT Detection
  14. GRB 260120B: COLIBRÍ optical upper limits
  15. SVOM GRB260121.06: Global MASTER-Net observations report
  16. GRB 260120B: Enhanced Swift-XRT position
  17. GRB 260120B: SVOM/C-GFT optical counterpart detection
  18. GRB 260120C: Fermi GBM Final Real-time Localization
  19. GRB 260101A: 239Alferov CubeSat detection
  20. EP260116a: COLIBRÍ observations of a tentative optical rebrightening
  21. GRB 260120B: Swift detection of a burst
  22. Swift GRB260120B: Global MASTER-Net observations report
  23. GRB 260120B: Fermi GBM Final Real-time Localization
  24. EP260119A: Mondy I-Band Observations
  25. Fermi trigger No 790601190: Global MASTER-Net observations report
  26. Fermi trigger No 790570272: Global MASTER-Net observations report
  27. GRB 260114A: Swift/UVOT Upper Limits
  28. EP260119a: Liverpool Telescope optical follow-up observations
  29. GRB 251202A: further radio observations with the VLA
  30. Trigger 1442421: Swift detection of HMXB 1A 1118-61
  31. EP260119A: GTC/OSIRIS+ spectroscopic redshift z = 5.47
  32. EP260119a: KAIT optical observations
  33. GRB 260120A: Fermi GBM Final Real-time Localization
  34. EP260119a: SVOM/VT optical observation
  35. EP260119a: update of EP-FXT follow-up observation
  36. EP260119a: NOT optical observations
  37. EP260119a: SAO RAS optical observations
  38. SVOM GRB260119.92: Global MASTER-Net observations report
  39. SVOM GRB260119.92: Global MASTER-Net observations report
  40. SVOM GRB260119.90: Global MASTER-Net observations report
  41. EP260116a: COLIBRÍ detection of a fading optical source
  42. GRB 251208D: SVOM/ECLAIRs refined analysis
  43. GRB 251208D: SVOM/ECLAIRs refined analysis
  44. GRB 260117A: Swift-XRT afterglow detection
  45. EP260119a: COLIBRÍ photometric redshift z ≈ 5.6
  46. EP260119a: Global MASTER-Net observations report
  47. GRB 260115A: AstroSat CZTI detection
  48. EP260119a: LCO optical observations
  49. GRB 260117A: ZTSh optical upper limit
  50. EP260119a: COLIBRÍ optical counterpart candidate
  51. EP260119a: preliminary result from the EP-FXT observation
  52. GRB 260110A: SVOM detection of a burst through offline search
  53. EP260119a: EP-WXT detection of a fast X-ray transient
  54. Swift GRB260118.48: Global MASTER-Net observations report
  55. GRB 260117A: SVOM/COLIBRÍ (FM-GFT) optical observations
  56. SVOM GRB260117.82: Global MASTER-Net observations report
  57. Fermi-LAT Gamma-ray Observations of IceCube-260115A
  58. Swift trigger on the HMXB 1A 1118-61
  59. GRB 260117A: SVOM/VT optical candidate
  60. GRB 260117A: SVOM/C-GFT upper limit
  61. GRB 260117A: Swift-XRT observations
  62. GRB 260117A: Swift ToO observations
  63. GRB 260117A: SVOM detection of a long faint burst
  64. EP 260116a: COLIBRÍ optical upper limit
  65. Swift triggered on the HMXB 1A 1118-61
  66. GRB 260115A: GECAM-B observation
  67. FRB 20251229A: COLIBRÍ further inspection of the updated localization
  68. EP260116a: Liverpool Telescope upper limits
  69. FRB 20251229A: Updated CHIME/FRB Baseband Localization of FRB 20251229A
  70. EP260116A: 1.3m DFOT optical upper limit
  71. GRB 260114A: VLT/MUSE spectroscopic observations
  72. IceCube-260115A: Upper limits from a search for additional neutrino events in IceCube
  73. EP260116a: Global MASTER-Net observations report
  74. GRB 260111A: COLIBRÍ fading of the optical counterpart candidate
  75. EP260116a: Einstein Probe detection of an X-ray transient
  76. GRB 260114A: VLT/HAWK-I further near-infrared upper limits
  77. IceCube Alert 260115.73: Global MASTER-Net observations report
  78. IceCube-260115A - IceCube observation of a high-energy neutrino candidate track-like event
  79. GRB 260115A: BALROG localization (Fermi Trigger 790192010 / GRB 260115741)
  80. IceCube: GCN Notices for high-energy track alerts now streamed via Kafka
  81. Fermi GRB 260115A: Global MASTER-Net observations report
  82. GRB 260115A: Fermi GBM Final Real-time Localization
  83. GRB260114A: STEP/T80S optical limits
  84. GRB 251222A: radio detection with the VLA
  85. GRB 260114A: VLT/HAWK-I near-infrared upper limits
  86. Konus-Wind detection of GRB 260114A
  87. GRB 260114A: Swift-XRT refined Analysis
  88. GRB 260114A: 6 GHz VLA observations
  89. GRB 260114A: VLT/X-shooter redshift of the putative host galaxy
  90. GRB 260114A : MITSuME Akeno optical upper limits
  91. GRB 260114A: COLIBRÍ optical upper limits
  92. GRB 260114A: TNG NIR upper limit
  93. GRB 260114A: NOT optical observations
  94. Konus-Wind detection of GRB 251230A / EP251230a
  95. GRB 260114A: SVOM/GRM observation of a short burst
  96. Swift GRB 260114A: Global MASTER-Net observations report
  97. GRB 260114A: GECAM-B observation of a short burst
  98. GRB 260114A: Mondy optical observations
  99. GRB 260114A: Fermi GBM observation
  100. GRB 260112B: GECAM-B observation

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