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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"

2677 results found.

  1. GRB 170607B: AstroSat CZTI detection
  2. GRB 170607A: MASTER-Tavrida early OT observations
  3. GRB 170519A: TShAO and AbAO optical observations
  4. Swift Trigger 755873: MASTER Net optical observations
  5. GRB 170531A: MASTER Net job
  6. LIGO/Virgo G268556: optical observations and classification of Pan-STARRS1 transients
  7. LIGO/Virgo G268556/GW170104: Konus-Wind observations
  8. GRB 170524B: MASTER-OAFA observations
  9. IPN Triangulation of GRB 170522B (long/intense)
  10. Konus-Wind observation of GRB 170522A
  11. AXP CXOU J164710.2-455216: Fermi GBM observation
  12. Konus-Wind observation of GRB 170510A
  13. Short GRB 170428A: MASTER-OAFA final reduction of the optical observations
  14. GRB 170428A: Swift detection of a short burst
  15. Swift Trigger 750044 is probably a noise fluctuation
  16. Konus-Wind observation of GRB 170424A
  17. GRB 170412A CALET Gamma-Ray Burst Monitor detection
  18. Konus-Wind observation of GRB 170409A
  19. GRB 170409A: Fermi GBM Observation
  20. Fermi trigger 512347439/GRB 170327A: MASTER-SAAO possible OT detection
  21. GRB 170331A: Swift detection of a burst
  22. Konus-Wind observation of GRB 170320A
  23. GRB 170320A: POLAR Observation
  24. IPN Triangulation of GRB 170320A (long/intense)
  25. IceCube-170312A: MASTER follow-up observations
  26. LIGO/Virgo G277583: ATLAS coverage and transients over the first 2 days
  27. GRB 170311A: Swift detection of a burst
  28. GRB170306A: SALT observations
  29. LIGO/Virgo G275404: REM optical/NIR observations
  30. LIGO/Virgo G275404: Swift-XRT sources
  31. LIGO/Virgo G275404: SVOM/Mini-GWAC: Observations of initial skymap
  32. LIGO/Virgo G274296: J-GEM optical/NIR follow-up observations
  33. LIGO/Virgo G274296: iPTF Optical Transient Candidates
  34. LIGO/Virgo G274296: Asiago 1.82m Optical Observations
  35. IPN Triangulation of GRB 170219A (short/hard)
  36. LIGO/Virgo G274296: Pan-STARRS imaging and discovery of 70 transients
  37. Konus-Wind observation of GRB 170207A
  38. IPN Triangulation of GRB 170207A (long/very bright)
  39. LIGO/Virgo G270580: Las Cumbres Observatory Follow-up Observations
  40. GRB 170126A: AstroSat CZTI detection
  41. GRB 170126A: Swift detection of a burst with an optical counterpart
  42. LIGO/Virgo G270580: Pan-STARRS coverage and 124 optical transients
  43. LIGO/Virgo G270580: Observations of initial skymap by Project Mini-GWAC of SVOM
  44. Trigger 731535: Swift detection of GRS 1716-249/GRO J1719-24/V2293 Oph
  45. LIGO/Virgo G268556: Pan-STARRS1 observations and summary of transient sources
  46. Trigger 731257: Another Swift-BAT detection of GRS 1716-249/GRO J1719-24/V2293 Oph
  47. Trigger 731183: Swift detection of GRS 1716-249/GRO J1719-24/V2293 Oph
  48. LIGO/Virgo G268556/GW170104: Lomonosov BDRG observations
  49. LIGO/Virgo G268556: ATLAS imaging of the skymap
  50. LIGO/Virgo G211117 / GW151226: LOFAR follow-up
  51. GRS 1716-249/GRO J1719-24/V2293 Oph, Swift-BAT refined analysis
  52. GRB161219.78 MASTER-Net OT detection
  53. GRB 161219B: Watcher optical observations
  54. IPN Triangulation of GRB 161218B (long/very bright)
  55. GRB 161219B: GROND afterglow observations
  56. GRB 161207A: POLAR observation
  57. GRB 161117A: MASTER-OAFA (Argentina) prompt OT observations
  58. GRB 161117B: Enhanced Swift-XRT position
  59. GRB 161117B: Swift detection of a burst
  60. GRB 161113A: Swift-XRT refined Analysis
  61. GRB 161105A: MASTER-IAC early optical observations
  62. GRB 161104A: Swift detection of a short burst
  63. GRB 161017A: MITSuME Akeno Optical Observation
  64. GRB 161007A: MASTER-net early optical observations
  65. GRB 160925A: Kottamia R-band observation
  66. GRB 160917A: Swift/UVOT Detection
  67. GRB 160917A: Mondy optical observations
  68. GRB 160912A: Fermi GBM detection
  69. GRB160821A: Astrosat CZTI (veto) detection
  70. GRB 160816A: MASTER inspection
  71. IPN Triangulation of GRB 160806A
  72. FACT follow-up of IceCube20160731
  73. Swift Trigger 704444 is probably not an astrophysical event.
  74. GRB 160623A: optical astrometry, photometry, and redshift
  75. GRB 160709A CALET Gamma-Ray Burst Monitor detection
  76. IPN Triangulation of GRB 160702A (short/hard)
  77. SGR 1935+2154: CALET Gamma-Ray Burst Monitor detections
  78. GRB 160705B: RATIR Optical and NIR Observations and Confirmation of the Fading Afterglow
  79. GRB 160705B: Swift-BAT refined analysis
  80. GRB 160705B: LT optical candidate
  81. GRB 160705B: Swift detection of a burst
  82. GRB 160625B: RTT150 optical observations
  83. GRB 160625B: Fermi-LAT refined analysis
  84. GRB 160623A: RATIR Optical and NIR Observations, Afterglow Confirmation
  85. GRB 160623A: Mondy optical observations
  86. GRB 160623A: Swift-XRT afterglow detection
  87. Konus-Wind observation of GRB 160607A
  88. GRB160601A: Kanata Telescope I- and Ks-bands upper limits
  89. Another Swift detection of SGR 1935+2154 (trigger #687124)
  90. GRB 160501A MASTER-NET early observations
  91. GRB 160501A: Swift detection of a burst
  92. MASTER search for counterpart to the IceCube event 67093193 (run 127853)
  93. LIGO/Virgo G211117: EWE for NOWT of 12 days follow-up of northern sky
  94. GRB 160412A: Swift detection of a burst
  95. GRB 160410A: GROND optical detection
  96. LIGO/Virgo G211117: LOFAR follow-up
  97. GRB 160324A: CALET Gamma-Ray Burst Monitor detection
  98. GRB 160325A, Swift-BAT refined analysis
  99. GRB 160325A: Swift detection of a burst
  100. GRB 160321A: Swift detection of a probable burst

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