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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"

35963 results found.

  1. Konus-Wind observation of GRB 180806A
  2. GRB 180809A: Fermi GBM observation
  3. GRB 180809A: CALET Gamma-Ray Burst Monitor detection
  4. GRB 180809B: CALET Gamma-Ray Burst Monitor detection
  5. Swift Trigger 852625: a possible GRB
  6. GRB 180809B: VLT optical upper limits
  7. GRB180809B: MASTER Triple Independent Automatic OT Detection
  8. GRB 180809B: LCO Sutherland observations
  9. GRB 180809B: GROND Detection of the NIR Afterglow
  10. GRB 180809B: RATIR Optical Observations and Confirmation of Rapid Fading
  11. GRB 180805B: Teide LCO optical observations
  12. GRB 180809A: iTelescope optical limit
  13. GRB 180809A: Swift-XRT afterglow detection
  14. GRB 180809B: Swift detection of a burst with an optical afterglow
  15. GRB 180809A: Tiled Swift observations
  16. GRB 180809A: MAXI/GSC detection
  17. GRB 180728A: AstroSat CZTI detection
  18. GRB 180724A: AstroSat CZTI detection
  19. GRB 180723A: AstroSat CZTI detection
  20. GRB 180806A: NOT optical observations
  21. GRB 180806A: Swift-XRT afterglow detection
  22. GRB 180806A/180806.98: RATIR Optical Observations of MASTER OT J004613.05+242014.1
  23. GRB 180806A: Fermi GBM detection
  24. GRB 180806A/180806.94: Refined COATLI Photometry of MASTER OT J004613.05+242014.1
  25. GRB 180806A: Swift ToO observations
  26. GRB 180806.94: COATLI Detection of MASTER OT J004613.05+242014.1 and Confirmation of Fading
  27. GRB 180806.94: MASTER possible OT detection in Fermi GMB trigger 555287944 error box
  28. GRB 180805B: ESO/NTT optical observations
  29. GRB 180805B: COATLI Optical Observations
  30. GRB 180805B: 1.5m OSN I-band observation
  31. GRB 180805B: GOTO optical limits
  32. GRB 180805B: VLT optical and near-infrared observations
  33. GRB 180805B: MASTER optical late inspection short GRB with extended emission
  34. GRB 180805A: Swift-XRT refined Analysis
  35. GRB 180805B: Swift-XRT refined Analysis
  36. GRB 180805B: Swift-BAT refined analysis (short GRB with extended emission)
  37. GRB 180805A: Swift-BAT refined analysis
  38. GRB 180805B: Swift/UVOT Upper Limits
  39. GRB 180805B: Fermi GBM detection
  40. GRB 180805B: Enhanced Swift-XRT position
  41. GRB 180805B: Swift detection of a burst
  42. GRB 180805A: Enhanced Swift-XRT position
  43. GRB 180805A: Swift detection of a burst
  44. GMRT radio detection of GRB 180720B
  45. GRB 180727A: Swift/BAT spectral lag result
  46. Fermi Trigger 554765006: MASTER optical inspection
  47. GRB 180728B: GOTO optical search over IPN region
  48. Fermi GBM trigger 554730582/180731493 is not a GRB
  49. GRB 180728A: No evidence of SN in early VLT/X-shooter spectra
  50. GRB 180728A: A long GRB of the X-ray flash (XRF) subclass, expecting supernova appearance
  51. GRB 180728B: MASTER optical observations short GRB IPN error box
  52. GRB 180728A: Swift/UVOT Detection
  53. GRB 180701A/MAXI J2119-045: CALET Gamma-Ray Burst Monitor data search
  54. GRB 180727A: Swift/UVOT Upper Limits
  55. Konus-Wind observation of the bright nearby GRB 180728A
  56. Konus-Wind observation of GRB 180728B
  57. GRB 180715A: CALET CAL gamma-ray analysis
  58. GRB 180703B: CALET CAL gamma-ray analysis
  59. GRB 180728B: Fermi GBM detection
  60. IPN Triangulation of GRB 180728B (short)
  61. GRB 180728A: VLT/X-shooter redshift of a nearby energetic GRB
  62. GRB 180728A: Swift-BAT refined analysis
  63. GRB 180728A: Fermi GBM observation
  64. GRB 180728A: Swift-XRT refined Analysis
  65. GRB 180728A: Enhanced Swift-XRT position
  66. GRB 180728A: MASTER OT J165415.75-540239.27 is the Optical Counterpart of GRB
  67. GRB 180728A: Swift-XRT observations
  68. GRB 180728A: MASTER OT (= new object) detection
  69. GRB 180727A: Swift-BAT refined analysis
  70. GRB 180728A: Swift detection of a bright burst
  71. GRB 180727A: Swift-XRT refined Analysis
  72. GRB 180727A: Fermi GBM observation
  73. GRB 180727A: Swift detection of a burst
  74. GRB 180720B: CALET Gamma-Ray Burst Monitor detection
  75. NuSTAR observations of GRB 180720B
  76. GRB 180720B: OAJ optical observations
  77. GRB 180722B: Insight-HXMT/HE detection
  78. GRB 180724A: Insight-HXMT/HE detection
  79. GRB 180720B: AMI-LA 15.5 GHz observation
  80. GRB 180720B long follow up requested
  81. GRB 180723A: Fermi GBM detection
  82. GRB 180721A: KAIT Optical Upper Limit
  83. GRB 180720B: KAIT Optical Observations
  84. GRB 180722A: Swift-XRT observations
  85. GRB 180718B: Swift-XRT observations
  86. GRB 180718A: Swift-XRT observations
  87. GRB 180723A: CALET Gamma-Ray Burst Monitor detection
  88. GRB 180722B: CALET Gamma-Ray Burst Monitor detection
  89. GRB 180723.13: MASTER optical observation of the short Fermi GBM trigger number 554008254
  90. GRB 180722A: MASTER second inspection
  91. GRB 180723.76: MASTER optical observation of the bright long Fermi GBM trigger number 554062193
  92. GRB 180720B: D50 optical observations
  93. GRB 180720B: MASTER Global Net OT observations
  94. GRB 180721A: MITSuME Akeno optical upper limits
  95. GRB 180720B: REM photometry
  96. GRB 180720B: ISON-Castelgrande optical observations
  97. GRB 180720B: Testing the universality of the newly born neutron star in BdHNe
  98. GRB 180721A: BOOTES-5/JGT optical observations
  99. GRB 180720B: COATLI Optical Detection
  100. GRB 180720C: BOOTES-2/TELMA optical observations

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