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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"

111 results found.

  1. GRB 240315B: AstroSat CZTI detection
  2. GRB 231129C: AGILE detection
  3. LIGO/Virgo S230525a: Global MASTER-Net observations report
  4. GRB230414B: VIRT Optical Upper Limit
  5. Fermi GRB 210615A: Global MASTER-Net observations report
  6. Fermi GBM observation of a bright burst from magneta
  7. LIGO/Virgo S200208q: Upper limits from Fermi-GBM Observations
  8. LIGO/Virgo S200208q: Identification of a GW compact binary merger candidate
  9. Fermi trigger No 588838851 Global MASTER-Net observations report
  10. GRB180523B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 548793993)
  11. Swift triggered on SAX J1806.5-221
  12. GRB 161214B: Swift detection of a burst
  13. GRB 160409A found in Swift BAT ground analysis
  14. Trigger 659734: Swift detection of SAX J1750.8-2900 or other source near Galactic center
  15. Konus-Wind observation of GRB 151006A
  16. Swift detection of SAX J1808.4-3658
  17. Swift detection of SAX J1712.6-3739
  18. Swift-BAT trigger 536502 is not astrophysical
  19. Swift Trigger 536502 is likely a noise fluctuation in coincidence with SAX J1818.6-1703
  20. Swift-BAT trigger 535733 is not astrophysical
  21. Trigger 535733: Swift possible detection of SAX J1828.5-1037
  22. SAX J1818.6-1703: Swift detection (trigger 306379)
  23. UVOT observations of SAXJ1810.8-2609
  24. Swift detection of a outburst from SAX J1810.8-2609
  25. GRB060604: Swift/UVOT detections
  26. GRB 060206: RAPTOR observations of afterglow candidate variability.
  27. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  28. IPN triangulation of GRB030717 (annulus)
  29. BeppoSAX GRB : GRB020409
  30. GRB020322: Candidate Optical Afterglow
  31. Bepposax GRB020322 The second springtime BSAX GRB
  32. GRB 011211 Optical Observations: Likely Afterglow
  33. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  34. GRB011121: BeppoSAX-WFC refined positions
  35. BEPPOSAX GRB011121
  36. The X-ray Flash 011030 ('GRB 011030')
  37. IPN triangulation of GRB010629
  38. Support extension to the BeppoSAX mission
  39. GRB010222: possible optical counterpart
  40. GRB010222
  41. GRB 010214, Optical Observations
  42. GRB000528, Radio Observations
  43. IPN triangulation of GRB000516
  44. BeppoSAX GRB000424
  45. GRB000419 [IPN Position]
  46. 1SAXJ1715.0-7134 refined position
  47. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  48. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  49. Budget cuts in BeppoSAX operations: impact on GRB observations
  50. GRB000226 [IPN Position]
  51. GRB 000210: BATSE Observations
  52. GRB000210, Radio Observations
  53. SAX_WFC_GRB_NOTICE
  54. SAX_WFC_GRB_NOTICE
  55. GCN resumes full operations
  56. IPN error box for GRB991216
  57. GRB 991217 (SAX J2303.2+0015) Optical observations
  58. GRB991217/SAX J2303.2+0015, optical observations
  59. SAX J2303.2+0015 Optical observations
  60. GRB 991217 (SAX J2303.2+0015) Optical observations
  61. GRB 991217
  62. SAX J2303.2+0015: an x-ray/GRB?
  63. BeppoSAX NFI Observation of GRB991106
  64. GRB 991105: BATSE Observations
  65. BeppoSAX refined position for GRB991106
  66. GRB991105: SAX-GRBM/-WFC detection
  67. BeppoSAX MAIL n. 99/30: GRB991105 refined position (fwd)
  68. GRB ALERT: GRB991105
  69. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  70. GRB990908, another BeppoSAX-GRBM/WFC burst detection
  71. GRB990806 BeppoSAX follow up
  72. GRB 990712
  73. Infrared and Optical Observations of GRB990705
  74. GRB990704: SAX-NFI results summary
  75. GRB 990704 X-ray Observations
  76. GRB990705: Intriguing Positional Coincidences
  77. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  78. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  79. Optical report on X-ray/GRB transient
  80. BeppoSAX: A new fast X-ray transient
  81. GRB990123, Probability of gravitational lensing
  82. GRB990123 IPN annulus
  83. GRB990123, refined SAX-WFC position
  84. GRB 981226 Optical Observations
  85. GRB981226 BeppoSAX follow up
  86. GRB980425: X-ray revised positions
  87. GRB980519, Optical Observations
  88. GRB980703, Host galaxy multicolor photometry
  89. GRB 980703 (NFI observations)
  90. BeppoSAX NFI observations of GRB 980703
  91. GRB980703
  92. GRB980613, optical observations
  93. GRB 980613 Optical Observations
  94. GRB980613 BeppoSAX-NFI follow up
  95. GRB980613, BeppoSAX WFC positions
  96. GRB980519 IPN POSITION
  97. GRB980515: SAX-WFC updated position
  98. BSAX Observations of GRB980425 field
  99. GRB980425 BATSE observations
  100. SAX J0840.7+2248 Optical Observations

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