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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"

28047 results found.

  1. LIGO/Virgo S190513bm: AGILE GRID observations
  2. LIGO/Virgo S190513bm: INTEGRAL prompt observation
  3. LIGO/Virgo S190513bm: AGILE MCAL observation
  4. LIGO/Virgo S190513bm: HAWC follow-up
  5. LIGO/Virgo S190513bm: Identification of a GW compact binary merger candidate
  6. LIGO/Virgo S190512at: Insight-HXMT/HE observation
  7. GRB 190512A: Swift-BAT refined analysis
  8. LIGO-Virgo S190512at: AGILE GRID observations
  9. LIGO/Virgo S190512at: Swift/BAT Counterpart Search
  10. LIGO/Virgo S190510g: Pan-STARRS and ATLAS observations and candidates
  11. LIGO/Virgo S190512at: ANTARES neutrino search
  12. LIGO/Virgo S190512at: Fermi-LAT search for a high-energy gamma-ray counterpart
  13. LIGO/Virgo S190512at: MAXI/GSC Observations
  14. LIGO/Virgo S190512at: Fermi GBM Observations
  15. LIGO/Virgo S190510g: Spectroscopic Classification of DECam-GROWTH and DES-GW Candidate DG19fqqk/desgw-190510c with Magellan
  16. GRB 190512A: Fermi GBM observation
  17. LIGO/Virgo S190512at: Identification of a GW compact binary merger candidate
  18. GRB 190511A: Swift-BAT refined analysis
  19. GRB 190511A: Swift-XRT refined Analysis
  20. IPN triangulation of GRB 190510A (short)
  21. LIGO/Virgo S190510g: DOAO Observation
  22. LIGO/Virgo S190510g: CALET Observations
  23. GRB 190511A: Swift/UVOT Detection
  24. LIGO/Virgo S190510g: KMTNet observation of DECam-GROWTH and DESGW candidates
  25. GRB 190511A: NOT optical afterglow
  26. LIGO/Virgo S190510g: Update on candidate significance
  27. LIGO/Virgo S190426c: VLA Follow-Up Observations of ZTF19aassfws
  28. LIGO/Virgo S190510g: GRAWITA VST-ESO PARANAL optical observations
  29. GRB 190511A: Enhanced Swift-XRT position
  30. LIGO/Virgo S190510g : Xinglong-60cm upper limit of the GRAWITA REM's OT
  31. LIGO/Virgo S190510g: Unconfirmed OT in PGC 094244
  32. LIGO/Virgo S190510g: Dabancheng/HMT Follow-Up Observations
  33. LIGO/Virgo S190510g: Xinglong/Schmidt Follow-Up Observations
  34. LIGO/Virgo S190510g: Pierre Auger Observatory follow-up
  35. GRB 190511A: Swift detection of a burst
  36. LIGO/Virgo S190510g: Insight-HXMT/HE updated observation
  37. LIGO/Virgo S190510g: SOAR/Goodman follow-up observations
  38. LIGO/Virgo S190510g: Optical Counterpart Candidates from DECam-GROWTH
  39. LIGO/Virgo S190510g: CNEOST Follow-Up Observations
  40. LIGO/Virgo S190510g: J-GEM optical/NIR follow-up observations
  41. LIGO/Virgo S190510g: Lick/KAIT Follow-Up Observations
  42. LIGO/Virgo S190510g: Updated classification and data quality report
  43. LIGO/Virgo S190510g: Fermi-LAT search for a high-energy gamma-ray counterpart
  44. LIGO-Virgo S190510g: AGILE GRID observations
  45. LIGO/Virgo S190510g: Potential host galaxies on the updated skymap from the GLADE catalog
  46. LIGO/Virgo S190510g: GRAWITA REM optical observations
  47. LIGO/Virgo S190510g: Swift/BAT Counterpart Search
  48. LIGO/Virgo S190510g: Insight-HXMT/HE observation
  49. LIGO/Virgo S190510g: HSC Y-band follow-up observation
  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. LIGO/Virgo S190510g: Potential host galaxies from the GLADE catalog
  54. LIGO/Virgo S190510g: Identification of a GW compact binary merger candidate
  55. LIGO/Virgo S190510g: HAWC follow-up
  56. LIGO/Virgo S190426c: Archival VLASS Observations of ZTF19aassfws 14 days prior to Merger
  57. LIGO-Virgo S190510g: AGILE MCAL observations
  58. LIGO/Virgo S190510g: IceCube Neutrino Search
  59. GRB 190508A: GOTO optical search - no counterparts
  60. Fermi GRB190507.71 Global MASTER-Net observations report
  61. GRB 190507B: GOTO optical counterpart search
  62. LIGO/Virgo S190426c (BHNS candidate): Implications from Numerical Relativity
  63. GRB 190501A: Swift XRT and UVOT Observations
  64. LIGO/Virgo S190426c: Konus-Wind observations
  65. LIGO/Virgo S190425z: Konus-Wind observations
  66. IceCube-190504A: MASTER optical monitoring analysis
  67. Fermi Trigger 578903308 / GRB 190507270 / GRB190507A: BALROG localization
  68. LIGO/Virgo S190426c: Update on Source Classification
  69. IceCube-190504A: Insight-HXMT/HE observation
  70. GRB 190501A: CALET Gamma-Ray Burst Monitor detection
  71. IceCube-190504A: Swift-XRT Follow-up Observations
  72. IceCube-190503A: Swift-XRT Follow-up Observations
  73. Fermi-LAT Gamma-ray Observations of IceCube-190504A
  74. Search for counterpart to IceCube-190504A with ANTARES
  75. IceCube-190503A: Insight-HXMT/HE observation
  76. LIGO/Virgo S190503bf Global MASTER-Net observations report
  77. LIGO/Virgo S190503bf: Swift/BAT Counterpart Search
  78. LIGO/Virgo S190503bf: Fermi-LAT search for a high-energy gamma-ray counterpart
  79. IceCube-190503A: Insight-HXMT/HE observation
  80. LIGO/Virgo S190503bf: ANTARES neutrino search
  81. Fermi-LAT Gamma-ray Observations of IceCube-190503A
  82. LIGO/Virgo S190503bf: Fermi-GBM Observations
  83. LIGO/Virgo S190503bf: MAXI/GSC Observations
  84. LIGO/Virgo S190503bf: AGILE-GRID Observations
  85. IceCube-190503A: INTEGRAL prompt observation
  86. LIGO/Virgo S190503bf: INTEGRAL prompt observation
  87. LIGO/Virgo S190503bf: Identification of a GW compact binary merger candidate
  88. LIGO/Virgo S190421ar: Updated localization and classification from LIGO and Virgo data
  89. GRB 190501A: GOTO optical counterpart search
  90. LIGO/Virgo S190425z: Insight-HXMT observation and counterpart search
  91. LIGO/Virgo S190426c: Gaia19boq 0.6m BOOTES-5/JGT, 1.5m OSN and 10.4m GTC observations
  92. Fermi Trigger 578462495 / GRB 190502168 / GRB190502A: BALROG localization
  93. GRB 190501A: AGILE/GRID detection
  94. LIGO/Virgo S190426c: ZTF19aaslzjf, ZTF19aasmftm and ZTF19aasmddt 1.5m OSN and 10.4m GTC observations
  95. LIGO/Virgo S190425z: Gaia Photometric Alerts transient candidates
  96. LIGO/Virgo S190426c: Swift rapid follow-up observations of S190425z and S190426c and URL for observation log for all future events
  97. LIGO/Virgo S190426c: GROWTH India follow-up of GRAWITA transient
  98. LIGO/Virgo S190412m: Further J-GEM optical/NIR observations
  99. LIGO/Virgo S190425z: 1.3-m optical imaging of UVOT transient field
  100. LIGO/Virgo S190426c: Fermi-LAT search for a high-energy gamma-ray counterpart

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