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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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').
Advanced Search

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"
  1. IPN triangulation of GRB 190510A (short)
  2. LIGO/Virgo S190510g: DOAO Observation
  3. LIGO/Virgo S190510g: CALET Observations
  4. GRB 190511A: Swift/UVOT Detection
  5. LIGO/Virgo S190510g: KMTNet observation of DECam-GROWTH and DESGW candidates
  6. GRB 190511A: NOT optical afterglow
  7. LIGO/Virgo S190510g: OT MASTER142812.05-013615.2 retraction as the kilonova candidate in GCN 24490
  8. LIGO/Virgo S190510g: MASTER OT detection inside low surface brightness galaxy
  9. LIGO/Virgo S190510g: Update on candidate significance
  10. LIGO/Virgo S190510g: Las Cumbres Observatory Galaxy Targeted Counterpart Search
  11. LIGO/Virgo S190510g: Non-detection of the OT in PGC 094244
  12. LIGO/Virgo S190426c: VLA Follow-Up Observations of ZTF19aassfws
  13. LIGO/Virgo S190510g: GRAWITA REM and Loiano optical observations
  14. LIGO/Virgo S190510g: GRAWITA VST-ESO PARANAL optical observations
  15. GRB 190511A: Fermi-LAT detection
  16. GRB 190511A: Fermi GBM observation
  17. GRB 190511A: Enhanced Swift-XRT position
  18. LIGO/Virgo S190510g: DESGW counterpart candidates over 80% of the GW localization area
  19. LIGO/Virgo S190510g : Xinglong-60cm upper limit of the GRAWITA REM's OT
  20. LIGO/Virgo S190510g: MASTER OT independ detection in WISE J060606.26-353233.9 galaxy at desgw-190510a position.
  21. LIGO/Virgo S190510g: Unconfirmed OT in PGC 094244
  22. LIGO/Virgo S190510g: Dabancheng/HMT Follow-Up Observations
  23. LIGO/Virgo S190510g: Xinglong/Schmidt Follow-Up Observations
  24. LIGO/Virgo S190510g: DESGW counterpart candidate (desgw-190510a)
  25. LIGO/Virgo S190510g: Pierre Auger Observatory follow-up
  26. GRB 190511A: Swift detection of a burst
  27. GRB 190511A: Fermi GBM Final Real-time Localization
  28. LIGO/Virgo S190510g: MASTER possible OT in PGC094244 galaxy
  29. LIGO/Virgo S190510g: Insight-HXMT/HE updated observation
  30. LIGO/Virgo S190510g: SOAR/Goodman follow-up observations
  31. LIGO/Virgo S190510g: Optical Counterpart Candidates from DECam-GROWTH
  32. LIGO/Virgo S190510g: KMTNet observation
  33. LIGO/Virgo S190510g: CNEOST Follow-Up Observations
  34. LIGO/Virgo S190510g: J-GEM optical/NIR follow-up observations
  35. LIGO/Virgo S190510g: Lick/KAIT Follow-Up Observations
  36. LIGO/Virgo S190510g: Updated classification and data quality report
  37. LIGO/Virgo S190510g: Lulin Optical Follow-up Observations
  38. LIGO/Virgo S190510g: Fermi-LAT search for a high-energy gamma-ray counterpart
  39. LIGO/Virgo S190425z: CAHA-GRANDMA Observation of the Swift UVOT Source
  40. LIGO-Virgo S190426c: Pan-STARRS non-detection of ZTF19aassfws
  41. LIGO-Virgo S190510g: AGILE GRID observations
  42. LIGO/Virgo S190510g: Potential host galaxies on the updated skymap from the GLADE catalog
  43. LIGO/Virgo S190510g: GRAWITA REM optical observations
  44. LIGO/Virgo S190510g: Swift/BAT Counterpart Search
  45. LIGO/Virgo S190510g: CLU/NED Galaxies in the Localization Volume
  46. Konus-Wind observation of GRB 190501A
  47. LIGO/Virgo S190510g: Insight-HXMT/HE observation
  48. LIGO/Virgo S190510g: HSC Y-band follow-up observation
  49. GRB 190510A: Fermi GBM Final Real-time Localization
  50. LIGO/Virgo S190510g: Updated localization from LIGO and Virgo data
  51. LIGO/Virgo S190510g: MAXI/GSC Observations
  52. LIGO/Virgo S190510g: ANTARES neutrino search
  53. S190510g: INTEGRAL inactive at the time of the event
  54. LIGO/Virgo S190510g: Potential host galaxies from the GLADE catalog
  55. LIGO/Virgo S190510g: Public DECam Observations
  56. LIGO/Virgo S190510g: Identification of a GW compact binary merger candidate
  57. LIGO/Virgo S190510g: HAWC follow-up
  58. LIGO/Virgo S190426c: Archival VLASS Observations of ZTF19aassfws 14 days prior to Merger
  59. Fermi GRB190510.12 Global MASTER-Net observations report
  60. LIGO/Virgo S190510g: Fermi GBM Observations
  61. LIGO-Virgo S190510g: AGILE MCAL observations
  62. LIGO/Virgo S190510g Global MASTER-Net observations report
  63. LIGO/Virgo S190510g: IceCube Neutrino Search
  64. LIGO/Virgo S190426c: Correction to typo in GCN 24433
  65. LIGO/Virgo S190426c: INT Observations of ZTF19aassfws
  66. GRB 190508A: GOTO optical search - no counterparts
  67. LIGO/Virgo S190503bf: TAROT-GRANDMA observation report
  68. LIGO/Virgo S190426c: Discovery Channel Telescope Follow-Up of ZTF19aassfws
  69. GRB 190508B: Fermi GBM Final Real-time Localization
  70. Fermi GRB190508.81 Global MASTER-Net observations report
  71. GRB 190508A: Fermi GBM Final Real-time Localization
  72. Fermi GRB190507.71 Global MASTER-Net observations report
  73. GRB 190507B: GOTO optical counterpart search
  74. Fermi GRB190508.11 Global MASTER-Net observations report
  75. Fermi GRB190507.97 Global MASTER-Net observations report
  76. GRB 190507B: Fermi GBM Final Real-time Localization
  77. Fermi GRB190507.27 Global MASTER-Net observations report
  78. LIGO/Virgo S190426c (BHNS candidate): Implications from Numerical Relativity
  79. GRB 190501A: Swift XRT and UVOT Observations
  80. LIGO/Virgo S190426c: Konus-Wind observations
  81. LIGO/Virgo S190425z: Konus-Wind observations
  82. IceCube-190504A: MASTER optical monitoring analysis
  83. LIGO/Virgo S190503bf: AstroSat CZTI upper limits
  84. Fermi Trigger 578903308 / GRB 190507270 / GRB190507A: BALROG localization
  85. GRB 190507A: Fermi GBM Final Real-time Localization
  86. Fermi GRB190506.58 Global MASTER-Net observations report
  87. LIGO/Virgo S190426c: Update on Source Classification
  88. Search for additional neutrino events from the direction of IceCube-190504A with IceCube
  89. Search for additional neutrino events from the direction of IceCube-190503A with IceCube
  90. Update to the Fermi GBM GCN Reporting
  91. IceCube-190504A: Insight-HXMT/HE observation
  92. GRB 190501A: CALET Gamma-Ray Burst Monitor detection
  93. IceCube-190504A: Swift-XRT Follow-up Observations
  94. IceCube-190503A: Swift-XRT Follow-up Observations
  95. LIGO/Virgo S190503bf: CALET Observations
  96. Fermi GRB190505.82 Global MASTER-Net observations report
  97. Fermi-LAT Gamma-ray Observations of IceCube-190504A
  98. Search for counterpart to IceCube-190504A with ANTARES
  99. IceCube-190503A: Insight-HXMT/HE observation
  100. Fermi GRB190505.05 Global MASTER-Net observations report

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