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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"

5833 results found.

  1. LIGO/Virgo G274296: Global MASTER Net SN bright detection during GW error box inspection
  2. LIGO/Virgo G274296: Observations of initial skymap by project Mini-GWAC of SVOM
  3. LIGO/Virgo G274296: REM optical/NIR observations
  4. GRB 170214A: GROND detection in all bands
  5. GRB 170208B: SMARTS optical/IR observations
  6. IPN Triangulation of GRB 170209A
  7. Correction to GCN 20640: GRB 170208B: GROND observations
  8. Fermi Trigger 508295323: MASTER-OAFA possible OT detection
  9. GRB 170208B: GROND observations
  10. GRB 170208B: Swift detection of a burst
  11. LIGO/Virgo G270580: Gemini-South Spectroscopic Classification of Optical Transients
  12. GRB 170205A: Swift detection of a burst with an optical counterpart
  13. GRB 170202A: SQUEAN Observation (2nd night)
  14. GRB 170202A: Swift detection of a burst with an optical afterglow
  15. LIGO/Virgo G270580: Las Cumbres Observatory Follow-up Observations
  16. LIGO/Virgo G270580: Swift/UVOT follow-up of PS17yt
  17. LIGO/Virgo G270580: Pan-STARRS coverage and 124 optical transients
  18. LIGO/Virgo G270580: A third optical transient from CNEOST
  19. LIGO/Virgo G270580: INTEGRAL search of temporally coincident prompt hard X-ray
  20. LIGO/Virgo G270580: Swift-XRT sources
  21. LIGO/Virgo G268556: Global MASTER Net 21 OTs detection
  22. LIGO/Virgo G270580: Observations of initial skymap by Project Mini-GWAC of SVOM
  23. GRB 170113A: Swift detection of a burst with an optical counterpart
  24. LIGO/Virgo G268556: Additional GROWTH follow up observation of iPTF Optical Transient Candidates
  25. LIGO/Virgo G268556: Liverpool Telescope Spectroscopy of iPTF17bv and iPTF17ck
  26. GRB 170109A: POLAR Observation
  27. LIGO/Virgo G268556: NOWT of EWE, Xinglong 0.6/0.9m, Xuyi 1m optical upper limits of ATLAS17aeu and a reminder of GCN 20394
  28. LIGO/Virgo G268556: Pan-STARRS1 observations and summary of transient sources
  29. LIGO/Virgo G268556: GWAC_F60B (60cm) follow-up two events of EWE001 and EWE002
  30. LIGO/Virgo G268556: Continued iPTF Observations and Additional Optical Transient Candidates
  31. LIGO/Virgo G268556: iPTF Optical Transient Candidates
  32. LIGO/Virgo G268556/GW170104: Asiago Observations
  33. LIGO/Virgo G268556: ATLAS17aeu - an unusual transient within the skymap
  34. LIGO/Virgo G268556/GW170104: Global MASTER Net observations and first OT detection
  35. LIGO/Virgo G268556: ATLAS imaging of the skymap
  36. LIGO/Virgo G211117 / GW151226: LOFAR follow-up
  37. LIGO/Virgo G268556: observation regions by Project Mini-GWAC of SVOM
  38. GRB 161220A: Swift detection of a burst
  39. GRB 161214B: Swift detection of a burst
  40. MASTER: Optical Blazar Flare Detection during Fermi trigger 502272781 inspection
  41. GRB 161202A: MITSuME Okayama upper limits
  42. GRB 161202A: Swift detection of a burst
  43. GRB 161129A: MITSuME Okayama Ks-band Observation
  44. GRB 161129A: MITSuME Okayama Optical Observation
  45. GRB 161123A: MAXI/GSC detection
  46. GRB 161117B: Swift detection of a burst
  47. GRB 161117A: Swift detection of a burst with an optical counterpart
  48. GRB 161108A: continued TSHAO optical observations
  49. GRB 161109A: Lomonosov BDRG gamma ray discovery
  50. GRB 161109A: Fermi-LAT detection
  51. GRB 161108A: Swift detection of a burst
  52. Fermi LAT Gamma-ray Observations of IceCube-161103
  53. IceCube-161103: Konus-Wind upper limits
  54. GRB 161105A: Swift detection of a burst
  55. IceCube-161103: Swift-XRT observations
  56. GRB 161104A: Swift detection of a short burst
  57. INTEGRAL SPI-ACS and IBIS/Veto observation of IceCube-161103
  58. IceCube-161103: MASTER follow-up observations
  59. HAWC follow up of IceCube-161103
  60. IceCube-161103: IceCube observation of a very-high-energy neutrino
  61. GRB 161023A: LCOGT-FTS optical observations
  62. Swift Trigger 718919 is not an astrophysical event.
  63. Swift Trigger 718766 is not an astrophysical event.
  64. GRB161017A optical R band observations with SARA-RM
  65. GRB 161017A: Lomonosov Gamma Ray and MASTER Optical prompt observations
  66. GRB 161017A: Swift/UVOT Detection
  67. GRB 161017A: Swift detection of a burst with a bright optical afterglow
  68. GRB161017.74 MASTER-Net OT detection
  69. GRB 161014A: Swift detection of a burst
  70. GRB 161007A: NOT optical observations
  71. GRB 161007A: Swift detection of a burst
  72. GRB 160925A: Kottamia R-band observation
  73. GRB 161004B: Swift detection of a burst
  74. GRB 161001A: MASTER-OAFA and MASTER-SAAO early optical observations
  75. GRB 161001A: GROND afterglow candidate
  76. GRB 160927A: NOT optical observations
  77. GRB 160927A: GROND Observations
  78. GRB 160925A/MASTER optical transient: Mondy optical observations
  79. GRB 160925A: MITSuME Akeno Optical Observations
  80. GRB 160925A: Bassano Bresciano Photometry of MASTER optical transient
  81. GRB 160925A: Optical spectroscopy of MASTER optical transient
  82. GRB 160925A / Fermi 496473540: Global MASTER Net OT discovery
  83. GRB 160917A: Mondy afterglow confirmation
  84. GRB 160910A: TSHAO optical observations
  85. GRB 160917A: RATIR Optical and NIR Observations
  86. GRB 160917A: Mondy optical observations
  87. GRB 160910A: Maidanak optical observations
  88. GRB 160912A: RATIR Optical and NIR Observations
  89. GRB 160912A: Mondy optical observations
  90. GRB 160910A: Mondy optical observations
  91. GRB 160910A: Global MASTER Net OT detection before LAT alert
  92. GRB 160912A: Swift detection of a burst
  93. IceCube HESE 160814: MASTER OT J130845.02-323254.9 as the possible source of the high energy neutrino
  94. GRB 160905A: Swift detection of a burst with an optical counterpart
  95. GRB 160827A: Swift detection of a burst
  96. GRB 160825A: not localized by Swift
  97. IPN Triangulation of GRB 160820A (short/hard)
  98. GRB 160821B: Swift detection of a short burst
  99. GRB 160814A: MAXI/GSC detection
  100. Swift Trigger 707545 is likely 4U 1850-03/GS1843-02

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