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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"

159 results found.

  1. The EP-WXT trigger 01709306297 is likely the known LMXB 4U 1745-203
  2. The EP-WXT trigger 01709291839 is likely the known LMXB 4U 1745-203
  3. GRB 260614A: AstroSat CZTI detection
  4. GRB 260403A: AstroSat CZTI detection
  5. EP251222b/GRB 251222A: SVOM/GRM observation
  6. GRB 250914A: AstroSat CZTI detection
  7. Fermi GRB 250909A: Global MASTER-Net observations report
  8. GRB 250506A: Swift XRT observations and possible counterpart detection
  9. Integral GRB241215.58: Global MASTER-Net observations report
  10. GRB 241105A: Fermi GBM Observation of a Short Burst with Extended Emission
  11. GRB 241025A: Swift-XRT refined Analysis
  12. LIGO/Virgo/KAGRA S240629by: Identification of a GW compact binary merger candidate
  13. LIGO/Virgo S240422ed: Swift-XRT detection of 3 possible counterparts
  14. Fermi GRB 240407A: Global MASTER-Net observations report
  15. Fermi trigger No 722349867: Global MASTER-Net observations report
  16. GRB 230628E: Swift/UVOT Detection
  17. GRB 230628E: Swift detection of a burst
  18. LIGO/Virgo S230616s: Global MASTER-Net observations report
  19. GRB 220711B: Swift/UVOT Upper Limits
  20. Konus-Wind detection of GRB 220613A
  21. GRB 220610B: AstroSat CZTI detection
  22. Fermi GRB 220514A: Global MASTER-Net observations report
  23. Fermi GRB 220309A: Global MASTER-Net observations report
  24. GRB 211206A: AstroSat CZTI detection
  25. GRB 210709A: AstroSat CZTI detection
  26. MAXI GRB210709.93: Global MASTER-Net observations report
  27. Fermi trigger No 642538568: Global MASTER-Net observations report
  28. GRB 210104A: Swift/UVOT Detection
  29. Swift GRB201024.12: Global MASTER-Net observations report
  30. SGR 1830-0645: Swift/UVOT Upper Limits
  31. GRB 200928B: AstroSat CZTI detection
  32. IceCube-200806A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  33. Fermi GRB 200607B: Global MASTER-Net observations report
  34. Swift GRB200303.11: Global MASTER-Net observations report
  35. Swift GRB200216.56: Global MASTER-Net observations report
  36. Konus-Wind observation of GRB 200120A
  37. GRB 200115A: CALET Gamma-Ray Burst Monitor detection
  38. GRB 190719C: Swift/UVOT Upper Limits
  39. GRB 180418A: TAROT La Silla observatory early optical observations
  40. GRB 180324A: Swift/UVOT Upper Limits
  41. Swift triggered on SAX J1806.5-221
  42. GRB 160409A found in Swift BAT ground analysis
  43. GRB 160327A: Swift/UVOT Upper Limits
  44. GRB 151027B: MASTER-NET early OT detection
  45. Trigger 659734: Swift detection of SAX J1750.8-2900 or other source near Galactic center
  46. Swift detection of SAX J1808.4-3658
  47. GRB 150222A: Swift-XRT refined Analysis
  48. GRB 141031A: Fermi GBM detection
  49. Swift detection of SAX J1712.6-3739
  50. GRB 140506A: Swift/UVOT Detection
  51. Konus-Wind observation of GRB 140213A
  52. GRB 130725B: Swift/UVOT Observations
  53. GRB 130725B: Swift/UVOT Detection of an Optical Counterpart
  54. Swift Trigger 558631: AAO optical observations
  55. GRB 130527A: Suzaku WAM observation of the prompt emission
  56. Swift-BAT trigger 536502 is not astrophysical
  57. Swift Trigger 536502 is likely a noise fluctuation in coincidence with SAX J1818.6-1703
  58. Swift-BAT trigger 535733 is not astrophysical
  59. Trigger 535733: Swift possible detection of SAX J1828.5-1037
  60. GRB 120305A: Swift/UVOT Upper Limits
  61. Swift-BAT refined analysis of outburst from 1E 1841-04.5
  62. GRB 110128A: Swift/UVOT observations
  63. GRB101024A: Swift/UVOT
  64. GRB 081125: Fermi GBM detection
  65. GRB 080506: Enhanced Swift-XRT position
  66. SAX J1818.6-1703: Swift detection (trigger 306379)
  67. UVOT observations of SAXJ1810.8-2609
  68. Swift detection of a outburst from SAX J1810.8-2609
  69. GRB 060717: Swift detection of a burst
  70. Bright short hard GRB 060303: IPN localization and Konus spectrum
  71. GRB050813: SWIFT/UVOT observation
  72. GRB 050714B: refined XRT analysis
  73. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  74. BeppoSAX GRB : GRB020409
  75. GRB020322: Candidate Optical Afterglow
  76. Bepposax GRB020322 The second springtime BSAX GRB
  77. GRB 011211 Optical Observations: Likely Afterglow
  78. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  79. GRB011121: BeppoSAX-WFC refined positions
  80. BEPPOSAX GRB011121
  81. The X-ray Flash 011030 ('GRB 011030')
  82. IPN triangulation of GRB010629
  83. Support extension to the BeppoSAX mission
  84. GRB010222: possible optical counterpart
  85. GRB010222
  86. GRB 010214, Optical Observations
  87. GRB000528, Radio Observations
  88. IPN triangulation of GRB000516
  89. BeppoSAX GRB000424
  90. GRB000419 [IPN Position]
  91. 1SAXJ1715.0-7134 refined position
  92. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  93. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  94. Budget cuts in BeppoSAX operations: impact on GRB observations
  95. GRB000226 [IPN Position]
  96. GRB 000210: BATSE Observations
  97. GRB000210, Radio Observations
  98. SAX_WFC_GRB_NOTICE
  99. SAX_WFC_GRB_NOTICE
  100. GCN resumes full operations

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