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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

11836 results found.

  1. LIGO/Virgo S190425z: ZTF19aarykkb Imaging from Las Cumbres Observatory
  2. LIGO/Virgo S190425z: CLU/NED Galaxies in the Localization Volume
  3. LIGO/Virgo S190425z: Lulin Follow-Up Observations
  4. LIGO/Virgo S190425z: J-GEM optical follow-up observations with Subaru/FOCAS
  5. LIGO/Virgo S190425z: AGILE-GRID Observations
  6. LIGO/Virgo S190425z: Lick/KAIT Follow-Up Observations
  7. LIGO/Virgo S190425z: further analysis of INTEGRAL data
  8. LIGO/Virgo S190425z: MAXI/GSC Observations
  9. LIGO/Virgo S190421ar: Fermi-LAT search for a high-energy gamma-ray counterpart
  10. LIGO/VirgoS190425z: HAWC follow-up
  11. Fermi GRB190425.09 Global MASTER-Net observations report
  12. GRB 190424A: Swift detection of a burst
  13. LIGO/Virgo S190421ar: TAROT-GRANDMA observation report.
  14. LIGO/Virgo S190421ar: Lick/KAIT Follow-Up Observations
  15. LIGO/Virgo S190421ar: MAXI/GSC Observations
  16. Swift GRB190422.96 Global MASTER-Net observations report
  17. Fermi GRB190422.67 Global MASTER-Net observations report
  18. LIGO/Virgo S190421ar Global MASTER-Net observations report
  19. LIGO/Virgo S190421ar: HAWC follow-up
  20. Konus-Wind observation of GRB 190415A
  21. Fermi GRB190420.98 Global MASTER-Net observations report
  22. LIGO/Virgo S190412m: SVOM/GWAC observations of the initial skymap
  23. Fermi GRB190419.41 Global MASTER-Net observations report
  24. Fermi trigger 576241792 / GRB 190406B: MASTER optical observation
  25. LIGO/Virgo S190412m: TAROT-GRANDMA observation report.
  26. Fermi GRB190415.17 Global MASTER-Net observations report
  27. LIGO/Virgo S190412m: GOTO optical coverage - no notable counterparts
  28. LIGO/Virgo S190412m: Fermi-LAT search for a high-energy gamma-ray counterpart
  29. LIGO/Virgo S190412m: J-GEM optical/NIR follow-up observations
  30. LIGO/Virgo S190412m: MAXI/GSC Observations
  31. LIGO-Virgo S190412m: AGILE GRID observations
  32. LIGO/Virgo S190412m: HAWC follow-up
  33. LIGO/Virgo S190412m: MASTER early alert observation
  34. LIGO/Virgo S190408an: Pan-STARRS observations and transients in the skymap
  35. LIGO/Virgo S190408an: MAXI/GSC Observations
  36. GRB 190404C: MITSuME Akeno and Okayama optical upper limits
  37. LIGO/Virgo S190408an: TMTS Optical Observation
  38. Konus-Wind observation of GRB 190404B
  39. LIGO/Virgo ST190408an: Fermi-LAT search for a high-energy gamma-ray counterpart
  40. CORRECTED TARGET NAME: GRB 190408A: MAXI/GSC detection
  41. GRB 140408A: MAXI/GSC detection
  42. LIGO-Virgo S190408an: HAWC follow-up
  43. LIGO-Virgo GW S190408an: J-GEM optical/NIR follow-up observations
  44. GRB 190404B: CALET Gamma-Ray Burst Monitor detection
  45. GRB 190331C: AstroSat CZTI detection
  46. GRB190404C: GROWTH-India discovery of optical counterpart
  47. GRB 140404C: MAXI/GSC detection
  48. GRB 140404B: MAXI/GSC detection
  49. GRB 190330A: MITSuME Akeno and Okayama optical upper limits
  50. LIGO/Virgo: Announcing the start of Observing Run 3 (O3) and the beginning of the public gravitational-wave alert era
  51. Konus-Wind observation of GRB 190329A
  52. Fermi-LAT Gamma-ray Observations of IceCube-190331A
  53. GRB 190401A: Insight-HXMT/HE detection
  54. MAGIC follow-up of the X-ray flares of LS I +61�303 dete
  55. Swift Trigger 895257: Detection of GRO J2058+42 in outburst
  56. Konus-Wind observation of GRB 190324A
  57. GRB 190324A: Swift-XRT refined Analysis
  58. GRB 190324A: Swift-XRT observations
  59. SWIFT GRB190323.85 Global MASTER-Net observations report
  60. Swift detection of LS I +61 303
  61. GRB190320A: MASTER GRB counterpart decay
  62. GRB 190320A: Fermi GBM observation
  63. GRB190320A: MASTER OT detection
  64. SWIFT GRB190320.05 Global MASTER-Net observations report
  65. GRB 190320A: Swift detection of a burst
  66. Fermi trigger 574140965 / GRB190313.15: MASTER Global Robotic Net optical observation
  67. GRB 190311A: Swift-BAT refined analysis
  68. GRB190305A: MASTER Global Robotic Net optical observation
  69. Improved Fermi/GBM GRB localizations
  70. GRB 190311A: Swift-XRT refined Analysis
  71. GRB 190311A: Swift detection of a burst with optical counterpart
  72. GRB 190305A: Swift-XRT afterglow detection
  73. Konus-Wind observation of GRB 190304A
  74. Konus-Wind observation of GRB 190305A
  75. GRB 190306A: MAXI/GSC detection
  76. GRB 190305A: Swift-XRT observations
  77. GRB 190305A: MAXI/GSC detection
  78. INTEGRAL observation of IceCube-190221A
  79. Search for additional neutrino events from the direction of IceCube-190221A with IceCube
  80. IceCube-190221A: Fermi-LAT Gamma-ray observations
  81. GRB 190220B: Fermi GBM observation
  82. GRB 190219A: CrAO and AbAO optical upper limit
  83. GRB 190220B: Kitab Observatory optical upper limit
  84. GRB 190220B: BOOTES-4 optical observation
  85. GRB 190220B: a long GRB detected by IBAS
  86. GRB 190219A: NOT optical afterglow candidate
  87. GRB 190219A: Swift-XRT refined Analysis
  88. GRB190219A: MASTER Global Robotic Net optical observation
  89. GRB 190211A: Swift-XRT refined Analysis
  90. GRB 190211A: Swift detection of a burst
  91. Konus-Wind observation of GRB 190206A
  92. IPN Triangulation of GRB 190206A (short/extremely bright)
  93. GRB 190202A: AstroSat CZTI detection
  94. Konus-Wind observation of GRB 190204A
  95. GRB 190203A: AstroSat CZTI detection
  96. GRB 190204A: Swift/UVOT Detection
  97. GRB 190203A: Liverpool Telescope near-IR observations
  98. Konus-Wind observation of GRB 190203A
  99. GRB 190204A: AstroSat CZTI detection
  100. GRB 190204A: Swift detection of a burst with a possible optical counterpart

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