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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"

15404 results found.

  1. GRB 190511A: NOT optical afterglow
  2. LIGO/Virgo S190510g: Update on candidate significance
  3. LIGO/Virgo S190510g: GRAWITA REM and Loiano optical observations
  4. GRB 190511A: Fermi-LAT detection
  5. LIGO/Virgo S190510g: DESGW counterpart candidates over 80% of the GW localization area
  6. LIGO/Virgo S190510g : Xinglong-60cm upper limit of the GRAWITA REM's OT
  7. LIGO/Virgo S190510g: Dabancheng/HMT Follow-Up Observations
  8. LIGO/Virgo S190510g: Xinglong/Schmidt Follow-Up Observations
  9. LIGO/Virgo S190510g: DESGW counterpart candidate (desgw-190510a)
  10. LIGO/Virgo S190510g: Pierre Auger Observatory follow-up
  11. LIGO/Virgo S190510g: Insight-HXMT/HE updated observation
  12. LIGO/Virgo S190510g: SOAR/Goodman follow-up observations
  13. LIGO/Virgo S190510g: Optical Counterpart Candidates from DECam-GROWTH
  14. LIGO/Virgo S190510g: CNEOST Follow-Up Observations
  15. LIGO/Virgo S190510g: Fermi-LAT search for a high-energy gamma-ray counterpart
  16. LIGO-Virgo S190510g: AGILE GRID observations
  17. LIGO/Virgo S190510g: Potential host galaxies on the updated skymap from the GLADE catalog
  18. LIGO/Virgo S190510g: Swift/BAT Counterpart Search
  19. LIGO/Virgo S190510g: CLU/NED Galaxies in the Localization Volume
  20. Konus-Wind observation of GRB 190501A
  21. LIGO/Virgo S190510g: Insight-HXMT/HE observation
  22. LIGO/Virgo S190510g: HSC Y-band follow-up observation
  23. LIGO/Virgo S190510g: MAXI/GSC Observations
  24. LIGO/Virgo S190510g: ANTARES neutrino search
  25. LIGO/Virgo S190510g: Potential host galaxies from the GLADE catalog
  26. LIGO/Virgo S190510g: Public DECam Observations
  27. LIGO/Virgo S190510g: HAWC follow-up
  28. LIGO/Virgo S190426c: Archival VLASS Observations of ZTF19aassfws 14 days prior to Merger
  29. LIGO-Virgo S190510g: AGILE MCAL observations
  30. LIGO/Virgo S190426c: Correction to typo in GCN 24433
  31. GRB 190507B: GOTO optical counterpart search
  32. LIGO/Virgo S190503bf: AstroSat CZTI upper limits
  33. IceCube-190504A: Insight-HXMT/HE observation
  34. IceCube-190504A: Swift-XRT Follow-up Observations
  35. LIGO/Virgo S190503bf: CALET Observations
  36. Fermi-LAT Gamma-ray Observations of IceCube-190504A
  37. Search for counterpart to IceCube-190504A with ANTARES
  38. IceCube-190503A: Insight-HXMT/HE observation
  39. IPN triangulation of GRB 190504A (short)
  40. IceCube-190504A - IceCube observation of a high-energy neutrino candidate event
  41. LIGO/Virgo S190503bf: Swift/BAT Counterpart Search
  42. LIGO/Virgo S190503bf: Fermi-LAT search for a high-energy gamma-ray counterpart
  43. IceCube-190503A: Insight-HXMT/HE observation
  44. LIGO/Virgo S190503bf: ANTARES neutrino search
  45. Fermi-LAT Gamma-ray Observations of IceCube-190503A
  46. LIGO/Virgo S190503bf: Fermi-GBM Observations
  47. LIGO/Virgo S190503bf: MAXI/GSC Observations
  48. LIGO/Virgo S190503bf: AGILE-GRID Observations
  49. IceCube-190503A: INTEGRAL prompt observation
  50. LIGO/Virgo S190503bf: INTEGRAL prompt observation
  51. LIGO/Virgo S190503bf: AGILE MCAL observations
  52. IceCube-190503A - IceCube observation of a high-energy neutrino candidate event
  53. GRB 190501B: AstroSat CZTI detection
  54. IPN Triangulation of GRB 190501A (long/bright)
  55. GRB 190501A: Swift ToO observations
  56. GRB 190501A: GOTO optical counterpart search
  57. LIGO/Virgo S190425z: Insight-HXMT observation and counterpart search
  58. GRB 190501A: refined position from AGILE/GRID analysis
  59. GRB 190501A: AGILE/GRID detection
  60. GRB 190501A: AGILE/MCAL and scientific ratemeters detection of a burst
  61. LIGO/Virgo S190426c: ZTF19aaslzjf, ZTF19aasmftm and ZTF19aasmddt 1.5m OSN and 10.4m GTC observations
  62. LIGO/Virgo S190426c: Swift rapid follow-up observations of S190425z and S190426c and URL for observation log for all future events
  63. GRB 190429A: AstroSat CZTI detection
  64. LIGO/Virgo S190426c: GROWTH India follow-up of GRAWITA transient
  65. LIGO/Virgo S190426c: PS1 historical detections and ZTF photometry of Gaia19boq AT2019egk
  66. LIGO/Virgo S190425z: 1.3-m optical imaging of UVOT transient field
  67. LIGO/Virgo S190426c: YAHPT Optical Observation
  68. LIGO/Virgo S190426c: Fermi-LAT search for a high-energy gamma-ray counterpart
  69. LIGO/Virgo S190425z: DECam Observations of the UVOT Candidate Region
  70. LIGO/Virgo S190425z: RATIR non-detection of the Swift/UVOT source
  71. LIGO/Virgo S190425z: VISTA K-band observations of the Swift/UVOT Transient
  72. LIGO/Virgo S190426c: OAJ-GRANDMA observation report
  73. LIGO/Virgo S190425z: 1.5m OSN and 10.4m imaging of the UVOT source field
  74. LIGO/Virgo S190425z: Spectroscopic observations of two ZTF candidates with SOAR
  75. LIGO/Virgo S190425z: NOT photometry of ZTF19aasckkq
  76. LIGO/Virgo S190425z: No source found at UVOT source location at 6 hrs after LVC report
  77. LIGO/Virgo S190426c: DG19ytre and DG19kplb 1.5m OSN imaging and 10.4m GTC spectroscopy
  78. LIGO/Virgo S190425z: No Optical Detection of the Swift/UVOT Transient in ASAS-SN observations hours before and after discovery
  79. LIGO/Virgo S190425z: Pre-discovery NIR limits of the UVOT transient candidate from Gattini-IR
  80. GRB 190419A: AstroSat CZTI detection
  81. LIGO/Virgo S190425z: Further confirmation for the classification of PS19qp/AT 2019ebq as a supernova
  82. GRB 190427A: Fermi GBM detection
  83. LIGO/Virgo S190426c: GOTO optical coverage - no notable counterparts
  84. LIGO/Virgo S190426c: CNEOST Optical Observations
  85. LIGO/Virgo S190425z: CNEOST Optical Observations
  86. LIGO/Virgo S190426c: Optical Wide-field Search with the Zwicky Transient Facility
  87. LIGO/Virgo S190426c: Nanshan/NEXT Observation of Galaxies
  88. LIGO/Virgo S190426c: Insight-HXMT/HE observation
  89. LIGO/Virgo S190426c: CALET Observations
  90. LIGO/Virgo S190426c: Imaging confirmation and host spectroscopy of DG19vkgf
  91. GRB 190427A: BOOTES-1 and BOOTES-5/JGT early follow-up observations
  92. ANTARES follow-up of the GW candidate S190426c
  93. LIGO/Virgo S190426c: Red and blue transients identified with DECam
  94. LIGO/Virgo S190425z: Lijiang 2.4-m Telescope Follow-up Observations
  95. LIGO/Virgo S190425z: Fermi-LAT search for a high-energy gamma-ray counterpart
  96. LIGO/Virgo S190426c: MAXI/GSC Observations
  97. LIGO/Virgo S190426c: Public DECam Observations
  98. LIGO/Virgo S190426c: Swift/BAT Counterpart Search
  99. LIGO/Virgo S190425z: GRAWITA LBT spectroscopic observations
  100. LIGO/Virgo S190426c: Nemo is Unrelated

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