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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"

24758 results found.

  1. GRB 170428A: TNG optical observations
  2. GRB 170428A: TAROT La Silla observatory optical observations
  3. GRB 170428A: RATIR Afterglow Confirmation
  4. GRB 170428A: GROND detection of the afterglow
  5. GRB 170428A: Swift/UVOT Upper Limits
  6. GRB 170428A: Xinglong 2.16-m upper limit and host galaxy candidate
  7. GRB 170428A: Swift-XRT refined Analysis
  8. GRB 170428A: Swift-BAT refined analysis
  9. Swift Trigger 750337 is probably a noise fluctuation
  10. GRB 170428A: Swift detection of a short burst
  11. GRB170426.95 MASTER-Net OT detection
  12. Swift Trigger 750096 is probably a noise fluctuation
  13. Swift Trigger 750044 is probably a noise fluctuation
  14. GRB 170424A: LCO Observations
  15. GRB 170419A: Swift/UVOT Upper Limits
  16. GRB 170424A: Fermi GBM detection
  17. GRB 170424A: Fermi-LAT detection
  18. GRB 170419A: LCO Observations
  19. GRB 170423A: Fermi GBM detection
  20. Swift Trigger 748858: AbAO and TSHAO optical observations
  21. Swift Trigger 748858: TAROT La Silla observatory optical observations
  22. Swift Trigger 748858: RATIR Optical and NIR Observations
  23. GRB 170419B, Swift-BAT refined analysis
  24. GRB 170419B: Zadko observatory - Gingin optical observations
  25. GRB 170419A: Zadko observatory - Gingin optical observations
  26. GRB 170419A: Swift-XRT refined Analysis
  27. GRB 170419B: Fermi GBM observation
  28. GRB 170419A: Swift-BAT refined analysis
  29. Swift trigger 748858: Swift BAT, XRT, and UVOT refined analysis
  30. GRB 170419A: Enhanced Swift-XRT position
  31. GRB 170419A: Swift detection of a burst
  32. Swift Trigger 748858: Zadko observatory - Gingin optical observations
  33. Swift Trigger 748858: a possible GRB
  34. GRB 170409A: TAROT Reunion observatory optical observations
  35. GRB 170409A: Fermi GBM Observation
  36. GRB 170409A: Fermi-LAT detection
  37. GRB 170405A: SMARTS optical/IR afterglow observations
  38. GRB 170317A: SAO RAS optical observations
  39. GRB170405A, Swift-UVOT Detection
  40. GRB 170405A, Swift-BAT refined analysis
  41. GRB 170405A: Etelman observatory optical observations
  42. GRB 170405A: Swift-XRT refined Analysis
  43. GRB 170405A: RATIR Optical and NIR Observations
  44. Trigger 745966: Swift detection of 4U1850-03
  45. GRB 170405A: ISON/Terskol optical observations
  46. GRB 170405A: Watcher optical detection
  47. GRB 170405A: Redshift from OSIRIS/GTC
  48. GRB 170405A: TAROT Reunion observatory optical observations
  49. GRB 170405A: Enhanced Swift-XRT position
  50. GRB 170405A: Swift detection of a burst with an optical counterpart
  51. LIGO/Virgo G275697: Update on significance from offline analyses
  52. LIGO/Virgo G275404: Update on significance from offline analyses
  53. LIGO/Virgo G275404: European VLBI Network (EVN) follow-up of the near-IR transient in the AGL J1914+1043 field
  54. GRB 170325A: optical observations, possible OT/host detection
  55. Konus-Wind observation of GRB 170403A (short/hard)
  56. IPN Triangulation of GRB 170403A (short)
  57. GRB 170403A: Fermi GBM observation
  58. IceCube-170321A: Konus-Wind upper limits
  59. Swift Trigger 745090 is a noise trigger near NGC 5195
  60. Fermi-LAT Gamma-ray Observations of IceCube-170321
  61. Swift triggered on SAX J1806.5-221
  62. GRB 170330A: Swift-BAT refined analysis
  63. GRB 170331A: Swift-BAT refined analysis
  64. DOAO 1m telescope V, R, I observation of GRB 170317A
  65. GRB 170331A: Swift/UVOT Upper Limits
  66. IceCube-170321A: Swift-XRT observations
  67. GRB 170330A: Swift-XRT refined Analysis
  68. GRB 170331A: Swift-XRT refined Analysis
  69. GRB 170330A: Enhanced Swift-XRT position
  70. GRB 170331A: Enhanced Swift-XRT position
  71. GRB 170330A: Swift/UVOT Detection of a Fading Afterglow
  72. GRB 170330A: LCO Cerro Tololo observations
  73. LIGO/Virgo G275697: LOFAR follow-up
  74. GRB 170331A: LCO Sutherland observations
  75. GRB 170331A: Swift detection of a burst
  76. GRB 170330A: Swift detection of a burst
  77. GRB 170329A: Fermi GBM detection
  78. GRB 170329A: Fermi-LAT detection
  79. LIGO/Virgo G277583: Konus-Wind observations
  80. GRB 170325A, Swift-BAT detection of a short GRB
  81. GRB 170320A: POLAR Observation
  82. LIGO/Virgo G277583: INTEGRAL search for an X-ray and gamma-ray counterpart
  83. LIGO/Virgo G275697: AMI Large Array Search for a Radio Afterglow
  84. INTEGRAL SPI-ACS observation of AMON IceCube EHE 80305071 129307
  85. IPN Triangulation of GRB 170320A (long/intense)
  86. Search for counterpart to IceCube-170321A with ANTARES
  87. GRB 170317A: Mondy optical observations
  88. GRB 170318B: Swift-BAT refined analysis
  89. GRB 170318B: RATIR Optical and NIR Observations
  90. GRB 170317A: RATIR Optical and NIR Observations
  91. GRB 170318B: Swift/UVOT Upper Limits
  92. GRB 170318B: Swift-XRT refined Analysis
  93. GRB 170318A: Swift-XRT refined Analysis
  94. LIGO/Virgo G277583: CALET Observations
  95. GRB 170318A: RATIR Optical and NIR Observations
  96. GRB 170318A: Swift/UVOT Upper Limits
  97. GRB 170318B: Fermi GBM observation
  98. GRB 170318A: Swift-BAT refined analysis
  99. GRB 170317A: RATIR Optical and NIR Observations
  100. GRB 170318B: Enhanced Swift-XRT position

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