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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"

24781 results found.

  1. GRB 170510A: Global MASTER Net possible OT observations
  2. LIGO/Virgo G284239: Konus-Wind observations
  3. GRB 170510A: LCO possible counterpart
  4. GRB 170510A: Swift-XRT observations
  5. GRB 170510A: Fermi GBM observation
  6. LIGO/Virgo G284239: H.E.S.S. very-high energy gamma-ray follow-up
  7. LIGO/Virgo G284239: MAXI/GSC observations
  8. Swift Trigger 752193 is not a GRB
  9. LIGO/Virgo G284239: AstroSat CZTI upper limits
  10. GRB 170423A: TAROT Reunion observatory optical observations
  11. Swift XRT observations of GRB 170424A
  12. LIGO/Virgo G284239:SVOM/Mini-GWAC observations of the initial skymap
  13. LIGO/Virgo G284239: HAWC follow-up
  14. LIGO/Virgo G284239: MASTER automatic follow up and synchronous observations
  15. LIGO/Virgo G284239: Fermi-LAT search for a high-energy gamma-ray counterpart
  16. LIGO/Virgo G284239: TZAC TAROT network observations with TRE/TCA/TCH
  17. LIGO/Virgo: G284239 ANTARES search
  18. LIGO/Virgo G284239: Swift/BAT data search
  19. LIGO/Virgo G284239: AGILE GRID observations
  20. LIGO/Virgo G284239: INTEGRAL search for a prompt gamma-ray counterpart
  21. LIGO/Virgo G284239: AGILE MCAL Observations
  22. LIGO/Virgo G284239: IceCube neutrino observations
  23. GRB 170428A: GTC spectroscopic redshift of candidate host galaxy
  24. GRB 170428A: TNG optical observations
  25. GRB 170428A: TAROT La Silla observatory optical observations
  26. GRB 170428A: RATIR Afterglow Confirmation
  27. GRB 170428A: GROND detection of the afterglow
  28. GRB 170428A: Swift/UVOT Upper Limits
  29. GRB 170428A: Xinglong 2.16-m upper limit and host galaxy candidate
  30. GRB 170428A: Swift-XRT refined Analysis
  31. GRB 170428A: Swift-BAT refined analysis
  32. Swift Trigger 750337 is probably a noise fluctuation
  33. GRB 170428A: Swift detection of a short burst
  34. GRB170426.95 MASTER-Net OT detection
  35. Swift Trigger 750096 is probably a noise fluctuation
  36. Swift Trigger 750044 is probably a noise fluctuation
  37. GRB 170424A: LCO Observations
  38. GRB 170419A: Swift/UVOT Upper Limits
  39. GRB 170424A: Fermi GBM detection
  40. GRB 170424A: Fermi-LAT detection
  41. GRB 170419A: LCO Observations
  42. GRB 170423A: Fermi GBM detection
  43. Swift Trigger 748858: AbAO and TSHAO optical observations
  44. Swift Trigger 748858: TAROT La Silla observatory optical observations
  45. Swift Trigger 748858: RATIR Optical and NIR Observations
  46. GRB 170419B, Swift-BAT refined analysis
  47. GRB 170419B: Zadko observatory - Gingin optical observations
  48. GRB 170419A: Zadko observatory - Gingin optical observations
  49. GRB 170419A: Swift-XRT refined Analysis
  50. GRB 170419B: Fermi GBM observation
  51. GRB 170419A: Swift-BAT refined analysis
  52. Swift trigger 748858: Swift BAT, XRT, and UVOT refined analysis
  53. GRB 170419A: Enhanced Swift-XRT position
  54. GRB 170419A: Swift detection of a burst
  55. Swift Trigger 748858: Zadko observatory - Gingin optical observations
  56. Swift Trigger 748858: a possible GRB
  57. GRB 170409A: TAROT Reunion observatory optical observations
  58. GRB 170409A: Fermi GBM Observation
  59. GRB 170409A: Fermi-LAT detection
  60. GRB 170405A: SMARTS optical/IR afterglow observations
  61. GRB 170317A: SAO RAS optical observations
  62. GRB170405A, Swift-UVOT Detection
  63. GRB 170405A, Swift-BAT refined analysis
  64. GRB 170405A: Etelman observatory optical observations
  65. GRB 170405A: Swift-XRT refined Analysis
  66. GRB 170405A: RATIR Optical and NIR Observations
  67. Trigger 745966: Swift detection of 4U1850-03
  68. GRB 170405A: ISON/Terskol optical observations
  69. GRB 170405A: Watcher optical detection
  70. GRB 170405A: Redshift from OSIRIS/GTC
  71. GRB 170405A: TAROT Reunion observatory optical observations
  72. GRB 170405A: Enhanced Swift-XRT position
  73. GRB 170405A: Swift detection of a burst with an optical counterpart
  74. LIGO/Virgo G275697: Update on significance from offline analyses
  75. LIGO/Virgo G275404: Update on significance from offline analyses
  76. LIGO/Virgo G275404: European VLBI Network (EVN) follow-up of the near-IR transient in the AGL J1914+1043 field
  77. GRB 170325A: optical observations, possible OT/host detection
  78. Konus-Wind observation of GRB 170403A (short/hard)
  79. IPN Triangulation of GRB 170403A (short)
  80. GRB 170403A: Fermi GBM observation
  81. IceCube-170321A: Konus-Wind upper limits
  82. Swift Trigger 745090 is a noise trigger near NGC 5195
  83. Fermi-LAT Gamma-ray Observations of IceCube-170321
  84. Swift triggered on SAX J1806.5-221
  85. GRB 170330A: Swift-BAT refined analysis
  86. GRB 170331A: Swift-BAT refined analysis
  87. DOAO 1m telescope V, R, I observation of GRB 170317A
  88. GRB 170331A: Swift/UVOT Upper Limits
  89. IceCube-170321A: Swift-XRT observations
  90. GRB 170330A: Swift-XRT refined Analysis
  91. GRB 170331A: Swift-XRT refined Analysis
  92. GRB 170330A: Enhanced Swift-XRT position
  93. GRB 170331A: Enhanced Swift-XRT position
  94. GRB 170330A: Swift/UVOT Detection of a Fading Afterglow
  95. GRB 170330A: LCO Cerro Tololo observations
  96. LIGO/Virgo G275697: LOFAR follow-up
  97. GRB 170331A: LCO Sutherland observations
  98. GRB 170331A: Swift detection of a burst
  99. GRB 170330A: Swift detection of a burst
  100. GRB 170329A: Fermi GBM detection

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