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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"

2724 results found.

  1. LIGO/Virgo G277583: ERRATUM LV GCN 20871: TAROT Calern (TCA) observations
  2. LIGO/Virgo G277583: TAROT Calern (TCA) observations
  3. LIGO/Virgo G277583: SVOM/Mini-GWAC observations of the initial skymap
  4. LIGO/Virgo G270580: optical observations and classification of PS and MASTER sources
  5. IPN Triangulation of GRB 170305A (short)
  6. LIGO/Virgo G275697: Further Swift-XRT sources
  7. LIGO/Virgo G275697: SVOM/Mini-GWAC observations of the initial skymap
  8. LIGO/Virgo G275697: iPTF Optical Transient Candidates
  9. LIGO/Virgo G275404: iPTF Optical Transient Candidates
  10. LIGO/Virgo G275404: CNEOST optical observations
  11. GRB 170220A: POLAR Observation
  12. LIGO/Virgo G274296: J-GEM optical/NIR follow-up observations
  13. LIGO/Virgo G274296: Asiago 1.82m Optical Observations
  14. LIGO/Virgo G274296: PESSTO classification of 9 Pan-STARRS transients
  15. Konus-Wind observation of GRB 170219A (short/hard)
  16. LIGO/Virgo G274296: Pan-STARRS imaging and discovery of 70 transients
  17. GRB 170210A: POLAR observation
  18. IPN Triangulation of GRB 170210A
  19. GRB 170210A: Fermi GBM observation
  20. Konus-Wind observation of GRB 170209A
  21. GRB 170208A: Swift-BAT refined analysis
  22. GRB 170202A: SQUEAN Observation
  23. LIGO/Virgo G270580: Las Cumbres Observatory Follow-up Observations
  24. GRB 170115B: AGILE/SuperAGILE localisation
  25. LIGO/Virgo G270580: Liverpool Telescope classification of EM candidates
  26. LIGO/Virgo G270580: Pan-STARRS coverage and 124 optical transients
  27. GRB 170121B: MASTER early optical observations of the Swift possible XT
  28. LIGO/Virgo G268556/GW170104: MAXI/GSC observations
  29. GRB 170121B/Fermi trigger 506702667 MASTER-Amur OT detection
  30. LIGO/Virgo G270580: Observations of initial skymap by Project Mini-GWAC of SVOM
  31. GRB 170112A : AbAO optical observations
  32. GRB 170113A: Fermi GBM observations
  33. GRB 170112A: MASTER-OAFA (Argentina) early optical observations
  34. LIGO/Virgo G268556: Pan-STARRS1 observations and summary of transient sources
  35. LIGO/Virgo G268556/GW170104: Lomonosov BDRG observations
  36. LIGO/Virgo G268556: Continued iPTF Observations and Additional Optical Transient Candidates
  37. LIGO/Virgo G268556: SWASP optical imaging
  38. LIGO/Virgo G211117 / GW151226: LOFAR follow-up
  39. LIGO/Virgo G268556: Swift-XRT sources
  40. GRB 170101B: POLAR observation
  41. GRB 170101B: Lomonosov BDRG gamma ray discovery
  42. GRB 170101B: Astrosat CZTI detection
  43. GRB 170101B: Fermi GBM detection
  44. GRB 161214A: MASTER-IAC early optical observations
  45. GRB161219.78 MASTER-Net OT detection
  46. GRB 161219B: Rapid ALMA Observations & Detection
  47. GRB 161220A: Swift-XRT refined Analysis
  48. GRB 161219B: VLA Detection
  49. GRB 161219B: Swift/UVOT Detection
  50. GRB 161219B: LCO Sutherland observations
  51. GRB 161219B: Enhanced Swift-XRT position
  52. GRB 161219B: Swift detection of a burst with an optical afterglow
  53. GRB 161218A: CALET Gamma-Ray Burst Monitor detection
  54. Konus-Wind observation of GRB 161218A
  55. GRB 161218A: POLAR observation
  56. GRB 161218A: Swift detection of a burst
  57. GRB 161129A: ISON/UAFO optical observations
  58. GRB 161117A: SMARTS optical/IR afterglow observations
  59. GRB 161119A: MASTER-SAAO possible OT detection during Fermi Alert
  60. Konus-Wind observation of GRB 161117A
  61. GRB 161108A: NOT redshift
  62. IceCube-161103: MASTER follow-up observations
  63. GRB 161023A: LCOGT-FTS optical observations
  64. GRB 161023A (Integral trigger 7613) MASTER-Net bright OT detection
  65. Swift Trigger 718766 is not an astrophysical event.
  66. GRB 161017A: Lomonosov Gamma Ray and MASTER Optical prompt observations
  67. GRB 161014A: AROMA-N Optical Observation
  68. GRB 161014A : Xinglong TNT optical observation
  69. GRB 161010A: Swift/UVOT Possible Detection
  70. GRB 161010A: Swift-XRT afterglow detection
  71. GRB 160927A: 15 GHz upper limits from AMI
  72. GRB 161001A: MASTER-OAFA and MASTER-SAAO early optical observations
  73. GRB 161001A: GROND afterglow candidate
  74. GRB 161001A: X-shooter spectroscopy, candidate host galaxy and redshift
  75. GRB 161001A: Prompt enhanced Swift-XRT position
  76. GRB 160917A: Fermi GBM observation
  77. GRB 160910A: Swift-XRT afterglow detection
  78. GRB 160910A: Fermi GBM observation
  79. GRB 160905A: Swift detection of a burst with an optical counterpart
  80. Konus-Wind observation of GRB 160821A
  81. GRB 160816A: TSHAO optical observations
  82. BAT detection and localization of GRB 160819A
  83. GRB 160816A: ISON/UAFO optical observations
  84. IceCube 160806A: Lomonosov BDRG gamma ray prompt observations
  85. IPN Triangulation of GRB 160806A
  86. Swift Trigger 707545 is likely 4U 1850-03/GS1843-02
  87. Swift Trigger 707517 is probably not a GRB
  88. IPN Triangulation of GRB 160802A
  89. GRB 160804A: Swift detection of a burst
  90. GRB 160714A: MASTER early optical observations
  91. GRB 160714A: Swift-XRT observations
  92. GRB 160712A: Swift-XRT observations
  93. GRB 160625B: Global MASTER-Crimea prompt optical emission detection (fwd)
  94. GRB 160705A/MAXI J0748-149: MAXI/GSC detection
  95. GRB 160629A: AbAO optical observations
  96. GRB 160525B: Mondy optical upper limit
  97. Swift detection of SGR 1935+2154
  98. GRB 160521B: Fermi-LAT detection
  99. GRB 160521B: Fermi GBM detection
  100. GRB 160509A: VLA Detection

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