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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"

157 results found.

  1. GRB 260614A: AstroSat CZTI detection
  2. GRB 260403A: AstroSat CZTI detection
  3. EP251222b/GRB 251222A: SVOM/GRM observation
  4. GRB 250914A: AstroSat CZTI detection
  5. Fermi GRB 250909A: Global MASTER-Net observations report
  6. GRB 250506A: Swift XRT observations and possible counterpart detection
  7. Integral GRB241215.58: Global MASTER-Net observations report
  8. GRB 241105A: Fermi GBM Observation of a Short Burst with Extended Emission
  9. GRB 241025A: Swift-XRT refined Analysis
  10. LIGO/Virgo/KAGRA S240629by: Identification of a GW compact binary merger candidate
  11. LIGO/Virgo S240422ed: Swift-XRT detection of 3 possible counterparts
  12. Fermi GRB 240407A: Global MASTER-Net observations report
  13. Fermi trigger No 722349867: Global MASTER-Net observations report
  14. GRB 230628E: Swift/UVOT Detection
  15. GRB 230628E: Swift detection of a burst
  16. LIGO/Virgo S230616s: Global MASTER-Net observations report
  17. GRB 220711B: Swift/UVOT Upper Limits
  18. Konus-Wind detection of GRB 220613A
  19. GRB 220610B: AstroSat CZTI detection
  20. Fermi GRB 220514A: Global MASTER-Net observations report
  21. Fermi GRB 220309A: Global MASTER-Net observations report
  22. GRB 211206A: AstroSat CZTI detection
  23. GRB 210709A: AstroSat CZTI detection
  24. MAXI GRB210709.93: Global MASTER-Net observations report
  25. Fermi trigger No 642538568: Global MASTER-Net observations report
  26. GRB 210104A: Swift/UVOT Detection
  27. Swift GRB201024.12: Global MASTER-Net observations report
  28. SGR 1830-0645: Swift/UVOT Upper Limits
  29. GRB 200928B: AstroSat CZTI detection
  30. IceCube-200806A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  31. Fermi GRB 200607B: Global MASTER-Net observations report
  32. Swift GRB200303.11: Global MASTER-Net observations report
  33. Swift GRB200216.56: Global MASTER-Net observations report
  34. Konus-Wind observation of GRB 200120A
  35. GRB 200115A: CALET Gamma-Ray Burst Monitor detection
  36. GRB 190719C: Swift/UVOT Upper Limits
  37. GRB 180418A: TAROT La Silla observatory early optical observations
  38. GRB 180324A: Swift/UVOT Upper Limits
  39. Swift triggered on SAX J1806.5-221
  40. GRB 160409A found in Swift BAT ground analysis
  41. GRB 160327A: Swift/UVOT Upper Limits
  42. GRB 151027B: MASTER-NET early OT detection
  43. Trigger 659734: Swift detection of SAX J1750.8-2900 or other source near Galactic center
  44. Swift detection of SAX J1808.4-3658
  45. GRB 150222A: Swift-XRT refined Analysis
  46. GRB 141031A: Fermi GBM detection
  47. Swift detection of SAX J1712.6-3739
  48. GRB 140506A: Swift/UVOT Detection
  49. Konus-Wind observation of GRB 140213A
  50. GRB 130725B: Swift/UVOT Observations
  51. GRB 130725B: Swift/UVOT Detection of an Optical Counterpart
  52. Swift Trigger 558631: AAO optical observations
  53. GRB 130527A: Suzaku WAM observation of the prompt emission
  54. Swift-BAT trigger 536502 is not astrophysical
  55. Swift Trigger 536502 is likely a noise fluctuation in coincidence with SAX J1818.6-1703
  56. Swift-BAT trigger 535733 is not astrophysical
  57. Trigger 535733: Swift possible detection of SAX J1828.5-1037
  58. GRB 120305A: Swift/UVOT Upper Limits
  59. Swift-BAT refined analysis of outburst from 1E 1841-04.5
  60. GRB 110128A: Swift/UVOT observations
  61. GRB101024A: Swift/UVOT
  62. GRB 081125: Fermi GBM detection
  63. GRB 080506: Enhanced Swift-XRT position
  64. SAX J1818.6-1703: Swift detection (trigger 306379)
  65. UVOT observations of SAXJ1810.8-2609
  66. Swift detection of a outburst from SAX J1810.8-2609
  67. GRB 060717: Swift detection of a burst
  68. Bright short hard GRB 060303: IPN localization and Konus spectrum
  69. GRB050813: SWIFT/UVOT observation
  70. GRB 050714B: refined XRT analysis
  71. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  72. BeppoSAX GRB : GRB020409
  73. GRB020322: Candidate Optical Afterglow
  74. Bepposax GRB020322 The second springtime BSAX GRB
  75. GRB 011211 Optical Observations: Likely Afterglow
  76. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  77. GRB011121: BeppoSAX-WFC refined positions
  78. BEPPOSAX GRB011121
  79. The X-ray Flash 011030 ('GRB 011030')
  80. IPN triangulation of GRB010629
  81. Support extension to the BeppoSAX mission
  82. GRB010222: possible optical counterpart
  83. GRB010222
  84. GRB 010214, Optical Observations
  85. GRB000528, Radio Observations
  86. IPN triangulation of GRB000516
  87. BeppoSAX GRB000424
  88. GRB000419 [IPN Position]
  89. 1SAXJ1715.0-7134 refined position
  90. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  91. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  92. Budget cuts in BeppoSAX operations: impact on GRB observations
  93. GRB000226 [IPN Position]
  94. GRB 000210: BATSE Observations
  95. GRB000210, Radio Observations
  96. SAX_WFC_GRB_NOTICE
  97. SAX_WFC_GRB_NOTICE
  98. GCN resumes full operations
  99. IPN error box for GRB991216
  100. GRB 991217 (SAX J2303.2+0015) Optical observations

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