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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"

28050 results found.

  1. LIGO/Virgo S190512at: CALET Observations
  2. LIGO/Virgo S190513bm: MAXI/GSC Observations
  3. LIGO/Virgo S190510g: Further KMTNet observation of DECam-GROWTH and DESGW candidates
  4. LIGO/Virgo S190513bm: AGILE GRID observations
  5. LIGO/Virgo S190513bm: INTEGRAL prompt observation
  6. LIGO/Virgo S190513bm: AGILE MCAL observation
  7. LIGO/Virgo S190513bm: HAWC follow-up
  8. LIGO/Virgo S190513bm: Identification of a GW compact binary merger candidate
  9. LIGO/Virgo S190512at: Insight-HXMT/HE observation
  10. GRB 190512A: Swift-BAT refined analysis
  11. LIGO-Virgo S190512at: AGILE GRID observations
  12. LIGO/Virgo S190512at: Swift/BAT Counterpart Search
  13. LIGO/Virgo S190510g: Pan-STARRS and ATLAS observations and candidates
  14. LIGO/Virgo S190512at: ANTARES neutrino search
  15. LIGO/Virgo S190512at: Fermi-LAT search for a high-energy gamma-ray counterpart
  16. LIGO/Virgo S190512at: MAXI/GSC Observations
  17. LIGO/Virgo S190512at: Fermi GBM Observations
  18. LIGO/Virgo S190510g: Spectroscopic Classification of DECam-GROWTH and DES-GW Candidate DG19fqqk/desgw-190510c with Magellan
  19. GRB 190512A: Fermi GBM observation
  20. LIGO/Virgo S190512at: Identification of a GW compact binary merger candidate
  21. GRB 190511A: Swift-BAT refined analysis
  22. GRB 190511A: Swift-XRT refined Analysis
  23. IPN triangulation of GRB 190510A (short)
  24. LIGO/Virgo S190510g: DOAO Observation
  25. LIGO/Virgo S190510g: CALET Observations
  26. GRB 190511A: Swift/UVOT Detection
  27. LIGO/Virgo S190510g: KMTNet observation of DECam-GROWTH and DESGW candidates
  28. GRB 190511A: NOT optical afterglow
  29. LIGO/Virgo S190510g: Update on candidate significance
  30. LIGO/Virgo S190426c: VLA Follow-Up Observations of ZTF19aassfws
  31. LIGO/Virgo S190510g: GRAWITA VST-ESO PARANAL optical observations
  32. GRB 190511A: Enhanced Swift-XRT position
  33. LIGO/Virgo S190510g : Xinglong-60cm upper limit of the GRAWITA REM's OT
  34. LIGO/Virgo S190510g: Unconfirmed OT in PGC 094244
  35. LIGO/Virgo S190510g: Dabancheng/HMT Follow-Up Observations
  36. LIGO/Virgo S190510g: Xinglong/Schmidt Follow-Up Observations
  37. LIGO/Virgo S190510g: Pierre Auger Observatory follow-up
  38. GRB 190511A: Swift detection of a burst
  39. LIGO/Virgo S190510g: Insight-HXMT/HE updated observation
  40. LIGO/Virgo S190510g: SOAR/Goodman follow-up observations
  41. LIGO/Virgo S190510g: Optical Counterpart Candidates from DECam-GROWTH
  42. LIGO/Virgo S190510g: CNEOST Follow-Up Observations
  43. LIGO/Virgo S190510g: J-GEM optical/NIR follow-up observations
  44. LIGO/Virgo S190510g: Lick/KAIT Follow-Up Observations
  45. LIGO/Virgo S190510g: Updated classification and data quality report
  46. LIGO/Virgo S190510g: Fermi-LAT search for a high-energy gamma-ray counterpart
  47. LIGO-Virgo S190510g: AGILE GRID observations
  48. LIGO/Virgo S190510g: Potential host galaxies on the updated skymap from the GLADE catalog
  49. LIGO/Virgo S190510g: GRAWITA REM optical observations
  50. LIGO/Virgo S190510g: Swift/BAT Counterpart Search
  51. LIGO/Virgo S190510g: Insight-HXMT/HE observation
  52. LIGO/Virgo S190510g: HSC Y-band follow-up observation
  53. LIGO/Virgo S190510g: Updated localization from LIGO and Virgo data
  54. LIGO/Virgo S190510g: MAXI/GSC Observations
  55. LIGO/Virgo S190510g: ANTARES neutrino search
  56. LIGO/Virgo S190510g: Potential host galaxies from the GLADE catalog
  57. LIGO/Virgo S190510g: Identification of a GW compact binary merger candidate
  58. LIGO/Virgo S190510g: HAWC follow-up
  59. LIGO/Virgo S190426c: Archival VLASS Observations of ZTF19aassfws 14 days prior to Merger
  60. LIGO-Virgo S190510g: AGILE MCAL observations
  61. LIGO/Virgo S190510g: IceCube Neutrino Search
  62. GRB 190508A: GOTO optical search - no counterparts
  63. Fermi GRB190507.71 Global MASTER-Net observations report
  64. GRB 190507B: GOTO optical counterpart search
  65. LIGO/Virgo S190426c (BHNS candidate): Implications from Numerical Relativity
  66. GRB 190501A: Swift XRT and UVOT Observations
  67. LIGO/Virgo S190426c: Konus-Wind observations
  68. LIGO/Virgo S190425z: Konus-Wind observations
  69. IceCube-190504A: MASTER optical monitoring analysis
  70. Fermi Trigger 578903308 / GRB 190507270 / GRB190507A: BALROG localization
  71. LIGO/Virgo S190426c: Update on Source Classification
  72. IceCube-190504A: Insight-HXMT/HE observation
  73. GRB 190501A: CALET Gamma-Ray Burst Monitor detection
  74. IceCube-190504A: Swift-XRT Follow-up Observations
  75. IceCube-190503A: Swift-XRT Follow-up Observations
  76. Fermi-LAT Gamma-ray Observations of IceCube-190504A
  77. Search for counterpart to IceCube-190504A with ANTARES
  78. IceCube-190503A: Insight-HXMT/HE observation
  79. LIGO/Virgo S190503bf Global MASTER-Net observations report
  80. LIGO/Virgo S190503bf: Swift/BAT Counterpart Search
  81. LIGO/Virgo S190503bf: Fermi-LAT search for a high-energy gamma-ray counterpart
  82. IceCube-190503A: Insight-HXMT/HE observation
  83. LIGO/Virgo S190503bf: ANTARES neutrino search
  84. Fermi-LAT Gamma-ray Observations of IceCube-190503A
  85. LIGO/Virgo S190503bf: Fermi-GBM Observations
  86. LIGO/Virgo S190503bf: MAXI/GSC Observations
  87. LIGO/Virgo S190503bf: AGILE-GRID Observations
  88. IceCube-190503A: INTEGRAL prompt observation
  89. LIGO/Virgo S190503bf: INTEGRAL prompt observation
  90. LIGO/Virgo S190503bf: Identification of a GW compact binary merger candidate
  91. LIGO/Virgo S190421ar: Updated localization and classification from LIGO and Virgo data
  92. GRB 190501A: GOTO optical counterpart search
  93. LIGO/Virgo S190425z: Insight-HXMT observation and counterpart search
  94. LIGO/Virgo S190426c: Gaia19boq 0.6m BOOTES-5/JGT, 1.5m OSN and 10.4m GTC observations
  95. Fermi Trigger 578462495 / GRB 190502168 / GRB190502A: BALROG localization
  96. GRB 190501A: AGILE/GRID detection
  97. LIGO/Virgo S190426c: ZTF19aaslzjf, ZTF19aasmftm and ZTF19aasmddt 1.5m OSN and 10.4m GTC observations
  98. LIGO/Virgo S190425z: Gaia Photometric Alerts transient candidates
  99. LIGO/Virgo S190426c: Swift rapid follow-up observations of S190425z and S190426c and URL for observation log for all future events
  100. LIGO/Virgo S190426c: GROWTH India follow-up of GRAWITA transient

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