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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').

107 results found.

  1. Fermi GRB 210324B: Global MASTER-Net observations report
  2. GRB 201216C: Swift/UVOT Upper Limits
  3. Fermi GRB190425.09 Global MASTER-Net observations report
  4. Swift triggered on SAX J1806.5-221
  5. GRB 160409A found in Swift BAT ground analysis
  6. GRB 160119A: Swift/UVOT Upper Limits
  7. Trigger 659734: Swift detection of SAX J1750.8-2900 or other source near Galactic center
  8. Swift detection of SAX J1808.4-3658
  9. GRB 150110B: Enhanced Swift-XRT position
  10. Swift detection of SAX J1712.6-3739
  11. Swift-BAT trigger 536502 is not astrophysical
  12. Swift Trigger 536502 is likely a noise fluctuation in coincidence with SAX J1818.6-1703
  13. Swift-BAT trigger 535733 is not astrophysical
  14. Trigger 535733: Swift possible detection of SAX J1828.5-1037
  15. SAX J1818.6-1703: Swift detection (trigger 306379)
  16. UVOT observations of SAXJ1810.8-2609
  17. Swift detection of a outburst from SAX J1810.8-2609
  18. GRB050802: TNG optical observations
  19. GRB 050802.422: Fading of the afterglow and detection of the host
  20. GRB050802: Tentative absorption redshift
  21. GRB 050802: Swift/UVOT optical and UV detections
  22. GRB050802: CrAO optical observations
  23. GRB 050802: early Swift XRT analysis results
  24. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  25. BeppoSAX GRB : GRB020409
  26. GRB020322: Candidate Optical Afterglow
  27. Bepposax GRB020322 The second springtime BSAX GRB
  28. GRB 011211 Optical Observations: Likely Afterglow
  29. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  30. GRB011121: BeppoSAX-WFC refined positions
  31. BEPPOSAX GRB011121
  32. The X-ray Flash 011030 ('GRB 011030')
  33. IPN triangulation of GRB010629
  34. Support extension to the BeppoSAX mission
  35. GRB010222: possible optical counterpart
  36. GRB010222
  37. GRB 010214, Optical Observations
  38. GRB000528, Radio Observations
  39. IPN triangulation of GRB000516
  40. BeppoSAX GRB000424
  41. GRB000419 [IPN Position]
  42. 1SAXJ1715.0-7134 refined position
  43. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  44. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  45. Budget cuts in BeppoSAX operations: impact on GRB observations
  46. GRB000226 [IPN Position]
  47. GRB 000210: BATSE Observations
  48. GRB000210, Radio Observations
  49. SAX_WFC_GRB_NOTICE
  50. SAX_WFC_GRB_NOTICE
  51. GCN resumes full operations
  52. IPN error box for GRB991216
  53. GRB 991217 (SAX J2303.2+0015) Optical observations
  54. GRB991217/SAX J2303.2+0015, optical observations
  55. SAX J2303.2+0015 Optical observations
  56. GRB 991217 (SAX J2303.2+0015) Optical observations
  57. GRB 991217
  58. SAX J2303.2+0015: an x-ray/GRB?
  59. BeppoSAX NFI Observation of GRB991106
  60. GRB 991105: BATSE Observations
  61. BeppoSAX refined position for GRB991106
  62. GRB991105: SAX-GRBM/-WFC detection
  63. BeppoSAX MAIL n. 99/30: GRB991105 refined position (fwd)
  64. GRB ALERT: GRB991105
  65. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  66. GRB990908, another BeppoSAX-GRBM/WFC burst detection
  67. GRB990806 BeppoSAX follow up
  68. GRB 990712
  69. Infrared and Optical Observations of GRB990705
  70. GRB990704: SAX-NFI results summary
  71. GRB 990704 X-ray Observations
  72. GRB990705: Intriguing Positional Coincidences
  73. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  74. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  75. Optical report on X-ray/GRB transient
  76. BeppoSAX: A new fast X-ray transient
  77. GRB990123, Probability of gravitational lensing
  78. GRB990123 IPN annulus
  79. GRB990123, refined SAX-WFC position
  80. GRB 981226 Optical Observations
  81. GRB981226 BeppoSAX follow up
  82. GRB980425: X-ray revised positions
  83. GRB980519, Optical Observations
  84. GRB980703, Host galaxy multicolor photometry
  85. GRB 980703 (NFI observations)
  86. BeppoSAX NFI observations of GRB 980703
  87. GRB980703
  88. GRB980613, optical observations
  89. GRB 980613 Optical Observations
  90. GRB980613 BeppoSAX-NFI follow up
  91. GRB980613, BeppoSAX WFC positions
  92. GRB980519 IPN POSITION
  93. GRB980515: SAX-WFC updated position
  94. BSAX Observations of GRB980425 field
  95. GRB980425 BATSE observations
  96. SAX J0840.7+2248 Optical Observations
  97. report on BSAX observations of GRB980425
  98. GRB980329 IPN annulus
  99. GRB980329 near-IR observations
  100. GRB980329 near-IR observations

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