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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').

147 results found.

  1. LIGO/Virgo S240422ed: Swift-XRT detection of 3 possible counterparts
  2. Fermi GRB 240407A: Global MASTER-Net observations report
  3. Fermi trigger No 722349867: Global MASTER-Net observations report
  4. GRB 230628E: Swift/UVOT Detection
  5. GRB 230628E: Swift detection of a burst
  6. LIGO/Virgo S230616s: Global MASTER-Net observations report
  7. GRB 220711B: Swift/UVOT Upper Limits
  8. Konus-Wind detection of GRB 220613A
  9. GRB 220610B: AstroSat CZTI detection
  10. Fermi GRB 220514A: Global MASTER-Net observations report
  11. Fermi GRB 220309A: Global MASTER-Net observations report
  12. GRB 211206A: AstroSat CZTI detection
  13. GRB 210709A: AstroSat CZTI detection
  14. MAXI GRB210709.93: Global MASTER-Net observations report
  15. Fermi trigger No 642538568: Global MASTER-Net observations report
  16. GRB 210104A: Swift/UVOT Detection
  17. Swift GRB201024.12: Global MASTER-Net observations report
  18. SGR 1830-0645: Swift/UVOT Upper Limits
  19. GRB 200928B: AstroSat CZTI detection
  20. IceCube-200806A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  21. Fermi GRB 200607B: Global MASTER-Net observations report
  22. Swift GRB200303.11: Global MASTER-Net observations report
  23. Swift GRB200216.56: Global MASTER-Net observations report
  24. Konus-Wind observation of GRB 200120A
  25. GRB 200115A: CALET Gamma-Ray Burst Monitor detection
  26. GRB 190719C: Swift/UVOT Upper Limits
  27. GRB 180418A: TAROT La Silla observatory early optical observations
  28. GRB 180324A: Swift/UVOT Upper Limits
  29. Swift triggered on SAX J1806.5-221
  30. GRB 160409A found in Swift BAT ground analysis
  31. GRB 160327A: Swift/UVOT Upper Limits
  32. GRB 151027B: MASTER-NET early OT detection
  33. Trigger 659734: Swift detection of SAX J1750.8-2900 or other source near Galactic center
  34. Swift detection of SAX J1808.4-3658
  35. GRB 150222A: Swift-XRT refined Analysis
  36. GRB 141031A: Fermi GBM detection
  37. Swift detection of SAX J1712.6-3739
  38. GRB 140506A: Swift/UVOT Detection
  39. Konus-Wind observation of GRB 140213A
  40. GRB 130725B: Swift/UVOT Observations
  41. GRB 130725B: Swift/UVOT Detection of an Optical Counterpart
  42. Swift Trigger 558631: AAO optical observations
  43. GRB 130527A: Suzaku WAM observation of the prompt emission
  44. Swift-BAT trigger 536502 is not astrophysical
  45. Swift Trigger 536502 is likely a noise fluctuation in coincidence with SAX J1818.6-1703
  46. Swift-BAT trigger 535733 is not astrophysical
  47. Trigger 535733: Swift possible detection of SAX J1828.5-1037
  48. GRB 120305A: Swift/UVOT Upper Limits
  49. Swift-BAT refined analysis of outburst from 1E 1841-04.5
  50. GRB 110128A: Swift/UVOT observations
  51. GRB101024A: Swift/UVOT
  52. GRB 081125: Fermi GBM detection
  53. GRB 080506: Enhanced Swift-XRT position
  54. SAX J1818.6-1703: Swift detection (trigger 306379)
  55. UVOT observations of SAXJ1810.8-2609
  56. Swift detection of a outburst from SAX J1810.8-2609
  57. GRB 060717: Swift detection of a burst
  58. Bright short hard GRB 060303: IPN localization and Konus spectrum
  59. GRB050813: SWIFT/UVOT observation
  60. GRB 050714B: refined XRT analysis
  61. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  62. BeppoSAX GRB : GRB020409
  63. GRB020322: Candidate Optical Afterglow
  64. Bepposax GRB020322 The second springtime BSAX GRB
  65. GRB 011211 Optical Observations: Likely Afterglow
  66. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  67. GRB011121: BeppoSAX-WFC refined positions
  68. BEPPOSAX GRB011121
  69. The X-ray Flash 011030 ('GRB 011030')
  70. IPN triangulation of GRB010629
  71. Support extension to the BeppoSAX mission
  72. GRB010222: possible optical counterpart
  73. GRB010222
  74. GRB 010214, Optical Observations
  75. GRB000528, Radio Observations
  76. IPN triangulation of GRB000516
  77. BeppoSAX GRB000424
  78. GRB000419 [IPN Position]
  79. 1SAXJ1715.0-7134 refined position
  80. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  81. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  82. Budget cuts in BeppoSAX operations: impact on GRB observations
  83. GRB000226 [IPN Position]
  84. GRB 000210: BATSE Observations
  85. GRB000210, Radio Observations
  86. SAX_WFC_GRB_NOTICE
  87. SAX_WFC_GRB_NOTICE
  88. GCN resumes full operations
  89. IPN error box for GRB991216
  90. GRB 991217 (SAX J2303.2+0015) Optical observations
  91. GRB991217/SAX J2303.2+0015, optical observations
  92. SAX J2303.2+0015 Optical observations
  93. GRB 991217 (SAX J2303.2+0015) Optical observations
  94. GRB 991217
  95. SAX J2303.2+0015: an x-ray/GRB?
  96. BeppoSAX NFI Observation of GRB991106
  97. GRB 991105: BATSE Observations
  98. BeppoSAX refined position for GRB991106
  99. GRB991105: SAX-GRBM/-WFC detection
  100. BeppoSAX MAIL n. 99/30: GRB991105 refined position (fwd)

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