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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"

19543 results found.

  1. GRB 170531B: LCO observations
  2. GRB 170531A: Swift-XRT refined Analysis
  3. GROND observations of GRB 170531B
  4. GRB 170531B: Redshift from GTC/OSIRIS
  5. GRB 170531B: Enhanced Swift-XRT position
  6. GRB 170531B: CrAO confirmation of the afterglow
  7. GRB 170531A: Swift/UVOT Observations
  8. GRB 170531B: Swift detection of a burst
  9. GRB 170531A: Swift detection of a burst
  10. GRB 170519A: CrAO optical observations
  11. GRB 170524B: Swift-UVOT/XRT Confirmation of Afterglow
  12. IPN Triangulation of GRB 170529A (long)
  13. GRB 170519A: ISON/Multa optical observations
  14. LIGO/Virgo G268556: optical observations and classification of Pan-STARRS1 transients
  15. GRB 170526A: Swift/UVOT Upper Limits
  16. LIGO/Virgo G268556: VERITAS Very-High-Energy Gamma-Ray Observations
  17. GRB 170524A: RATIR Optical and NIR Observations
  18. GRB 170526A: Enhanced Swift-XRT position
  19. GRB 170526A: Swift detection of a burst
  20. GRB 170524B: MASTER-OAFA observations
  21. GRB 170524A: TSHAO and CrAO optical observations
  22. GRB 170524B: Swift ToO observations
  23. GRB 170524A: Swift-BAT refined analysis
  24. GRB 170524A: Swift/UVOT Upper Limits
  25. IPN Triangulation of GRB 170522A
  26. GRB 170524A: Enhanced Swift-XRT position
  27. GRB 170524A: Swift detection of a burst (or possible new SGR)
  28. GRB 170522A: LCO McDonald observations
  29. GRB 170522A: Global MASTER-Net job
  30. GRB 170522A: Tiled Swift observations
  31. GRB 170522A: Fermi-LAT detection
  32. GRB 170522A: Fermi GBM detection
  33. GRB 170519A: Watcher optical observations
  34. GRB 170519A: Continued RATIR Optical and NIR Observations
  35. GRB 170519A: MITSuME Okayama Optical Observation
  36. GRB 170519A: NOT optical observations
  37. GRB170519A, Swift-UVOT Detection
  38. GRB 170519A: Weihai optical observations
  39. GRB 170510A: LCO Siding Springs early observations
  40. GRB 170519A: RATIR Optical and NIR Observations
  41. GRB 170519A: optical observations
  42. GRB 170519A: Enhanced Swift-XRT position
  43. GRB 170519A: Swift detection of a burst with an optical counterpart
  44. GRB 170510A CALET Gamma-Ray Burst Monitor detection
  45. LIGO/Virgo G277583: UH88/SNIFS classification of ATLAS and PS1 transients
  46. GRB 170510A: Swift-XRT afterglow detection
  47. AXP CXOU J164710.2-455216: Fermi GBM observation
  48. GRB 170516A: Swift/UVOT Upper Limits
  49. GRB 170516A: Enhanced Swift-XRT position
  50. GRB 170516A: Swift detection of a burst
  51. Swift Trigger on AXP CXOU J164710.2-455216
  52. GRB 170510A: AstroSat CZTI(Veto) detection
  53. GRB 170510A: Global MASTER Net possible OT observations
  54. Konus-Wind observation of GRB 170510A
  55. GRB 170510A: LCO possible counterpart
  56. GRB 170510A: Swift-XRT observations
  57. GRB 170510A: Fermi GBM observation
  58. LIGO/Virgo G284239: H.E.S.S. very-high energy gamma-ray follow-up
  59. GRB 170510A: Tiled Swift observations
  60. GRB 170510A: Fermi-LAT detection
  61. Swift Trigger 752193 is not a GRB
  62. LIGO/Virgo G284239: AstroSat CZTI upper limits
  63. GRB 170423A: TAROT Reunion observatory optical observations
  64. Swift XRT observations of GRB 170424A
  65. LIGO/Virgo G284239:SVOM/Mini-GWAC observations of the initial skymap
  66. LIGO/Virgo G284239: HAWC follow-up
  67. LIGO/Virgo G284239: MASTER automatic follow up and synchronous observations
  68. LIGO/Virgo G284239: Fermi-LAT search for a high-energy gamma-ray counterpart
  69. LIGO/Virgo G284239: TZAC TAROT network observations with TRE/TCA/TCH
  70. LIGO/Virgo: G284239 ANTARES search
  71. LIGO/Virgo G284239: Swift/BAT data search
  72. LIGO/Virgo G284239: INTEGRAL search for a prompt gamma-ray counterpart
  73. GRB 170428A: GTC spectroscopic redshift of candidate host galaxy
  74. GRB 170428A: TNG optical observations
  75. GRB 170428A: TAROT La Silla observatory optical observations
  76. GRB 170428A: RATIR Afterglow Confirmation
  77. GRB 170428A: GROND detection of the afterglow
  78. GRB 170428A: Swift/UVOT Upper Limits
  79. GRB 170428A: Xinglong 2.16-m upper limit and host galaxy candidate
  80. GRB 170428A: Swift-XRT refined Analysis
  81. Swift Trigger 750337 is probably a noise fluctuation
  82. GRB 170428A: Swift detection of a short burst
  83. Swift Trigger 750096 is probably a noise fluctuation
  84. Swift Trigger 750044 is probably a noise fluctuation
  85. GRB 170424A: LCO Observations
  86. GRB 170419A: Swift/UVOT Upper Limits
  87. GRB 170424A: Tiled Swift observations
  88. GRB 170419A: LCO Observations
  89. Swift Trigger 748858: AbAO and TSHAO optical observations
  90. Swift Trigger 748858: TAROT La Silla observatory optical observations
  91. Swift Trigger 748858: RATIR Optical and NIR Observations
  92. GRB 170419B: Zadko observatory - Gingin optical observations
  93. GRB 170419A: Zadko observatory - Gingin optical observations
  94. Swift trigger 748858: Swift BAT, XRT, and UVOT refined analysis
  95. GRB 170419A: Enhanced Swift-XRT position
  96. GRB 170419A: Swift detection of a burst
  97. Swift Trigger 748858: Zadko observatory - Gingin optical observations
  98. Swift Trigger 748858: a possible GRB
  99. LIGO/Virgo G275404: DLT40 follow-up observation
  100. GRB 170409A: TAROT Reunion observatory optical observations

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