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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"

603 results found.

  1. Fermi GRB190520.6 Global MASTER-Net observations report
  2. LIGO/Virgo S190517h: CALET Observations
  3. LIGO/Virgo S190517h: INTEGRAL prompt observation
  4. LIGO/Virgo S190517h: INTEGRAL/SPI-ACS prompt observation
  5. LIGO/Virgo S190510g: J-GEM optical/NIR follow-up observations
  6. LIGO/Virgo S190412m: Further J-GEM optical/NIR observations
  7. GRB 190427A, Swift-BAT refined analysis
  8. LIGO/Virgo S190426c: CNEOST Optical Observations
  9. LIGO/Virgo S190425z: CNEOST Optical Observations
  10. LIGO/Virgo S190426c: SAO optical observation
  11. Fermi GRB190415.17 Global MASTER-Net observations report
  12. MAGIC follow-up of the X-ray flares of LS I +61�303 dete
  13. Swift detection of LS I +61 303
  14. IceCube-190221A: Swift-XRT Follow-up Observations
  15. GRB 190203A: MASTER OT detection
  16. Konus-Wind observation of GRB 190114C
  17. SWIFT GRB190106.57 Global MASTER-Net OT detection
  18. GRB 181126A: Swift/UVOT Upper Limits
  19. GRB 181027A: Fermi GBM detection
  20. GRB 181020A: Swift-XRT refined Analysis
  21. GRB 181010A: REM optical and NIR afterglow detection
  22. Konus-Wind observation of GRB 180828A
  23. GRB 180728B: MASTER optical observations short GRB IPN error box
  24. GRB 180728B: Fermi GBM detection
  25. GRB 180728A: MASTER OT (= new object) detection
  26. GRB 180722A: MASTER second inspection
  27. GRB 180720B: MASTER Global Net OT observations
  28. FRB 180714: MASTER optical inspection of the Fast Rado Burst Transient
  29. GRB 180718A: Fermi GBM detection
  30. Konus-Wind observation of GRB 180623A
  31. GRB 180623A: Swift detection of a burst
  32. GRB 180618A: MASTER OT observation (a short GRB with extended emission)
  33. GRB 180605A: Fermi GBM observation
  34. Konus-Wind observation of GRB 180523A
  35. GRB 180504A: Swift-BAT refined analysis
  36. Konus-Wind observation of GRB 180427A
  37. Konus-Wind observation of GRB 180316A
  38. GRB 180325A: Swift-XRT refined Analysis
  39. GRB 180224A: Swift/UVOT Detection
  40. Konus-Wind observation of GRB 180111A
  41. GRB 180113A: Swift-BAT refined analysis
  42. GRB 180102A: Swift-BAT refined analysis
  43. IceCube-171106A: Konus-Wind upper limits
  44. GRB 171209A: Swift-BAT refined analysis
  45. GRB 171112A: MAXI/GSC detection
  46. IceCube-171106A: Swift Observations
  47. GRB 171027A, Swift-BAT refined analysis
  48. Swift trigger 781740: Further analysis from Swift and Fermi/GBM
  49. Numerous Fermi-GBM Subthreshold Notices are due to Swift J0243.6+6
  50. Swift Trigger 775946 is a Galactic transient, not GRB 171003
  51. GRB 171003A: LT early optical observations
  52. GRB 170903A: Swift-BAT refined analysis
  53. Konus-Wind observation of GRB 170822A
  54. LIGO/Virgo G298048: ATCA observations of candidate host galaxies
  55. Konus-Wind observation of GRB 170728B
  56. GRB 170714A, Swift-BAT refined analysis
  57. Fermi GBM Detection of possible burst from AXP 4U 0142+61
  58. GRB 170710B: Fermi GBM observation
  59. Konus-Wind observation of GRB 170705A
  60. LIGO/Virgo G268556: optical observations and classification of Pan-STARRS1 transients
  61. GRB 170524A: Swift-BAT refined analysis
  62. Swift trigger 748858: Swift BAT, XRT, and UVOT refined analysis
  63. GRB 170405A: Swift detection of a burst with an optical counterpart
  64. LIGO/Virgo G270580: optical observations and classification of PS and MASTER sources
  65. LIGO/Virgo G275697: Updated localization from LIGO data
  66. LIGO/Virgo G275697: Swift-XRT sources
  67. Konus-Wind observation of GRB 170206A
  68. LIGO/Virgo G270580: Pan-STARRS coverage and 124 optical transients
  69. LIGO/Virgo G268556: Pan-STARRS1 observations and summary of transient sources
  70. LIGO/Virgo G268556: GWAC_F60B (60cm) follow-up two events of EWE001 and EWE002
  71. LIGO/Virgo G268556/GW170104: Asiago Observations
  72. LIGO/Virgo G268556: ATLAS17aeu - an unusual transient within the skymap
  73. GRB 161220A: Swift-BAT refined analysis
  74. GRB 161214A: fading optical afterglow candidate with the LT
  75. Konus-Wind observation of GRB 161202A
  76. GRB 161113A: Swift/UVOT Upper Limits
  77. GRB 161109A: Swift-XRT observations
  78. Konus-Wind observation of GRB 161020B
  79. GRB 161004A: Swift-BAT refined analysis
  80. GRB 160927A: Swift-BAT refined analysis
  81. GRB 160821B: Fermi GBM Detection
  82. IPN Triangulation of GRB 160720A
  83. GRB 160629A: SAO RAS independent OT detection
  84. GRB 160625B CALET Gamma-Ray Burst Monitor detection
  85. Konus-Wind observation of GRB 160625B
  86. Konus-Wind observation of GRB 160530A
  87. Konus-Wind observation of GRB 160521B
  88. SGR 1935+2154: AbAO optical upper limit
  89. GRB 160504A: Swift detection of a burst
  90. GRB 160424A: Swift-BAT refined analysis
  91. GRB 160412A: Swift-BAT refined analysis
  92. GRB 160303A, Swift-BAT refined analysis
  93. GRB 160221A: MASTER-SAAO early observations
  94. Konus-Wind observation of GRB 160220B
  95. LIGO/Virgo G211117: Further Swift-XRT sources
  96. Konus-Wind observation of GRB 151231A
  97. Konus-Wind observation of GRB 151225A
  98. GRB 160104A: MITSuME Akeno Optical Observation
  99. GRB 151231A: Fermi GBM observation
  100. GRB 151228B: Swift-BAT refined analysis

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