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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"

15246 results found.

  1. GRB 151122A: Swift ToO observations
  2. Konus-Wind observation of GRB 151120A
  3. GRB 151120A: Fermi GBM observation
  4. LIGO/Virgo G194575: Updated significance from offline GW analysis
  5. GRB 151120A: Swift ToO observations
  6. GRB 151120A: A long GRB detected by INTEGRAL
  7. LIGO/Virgo G194575: Fermi GBM Observations
  8. GRB 151027A: SAO RAS and Mt. Terskol observations
  9. GRB 151114A: GROND Detection of the Optical/NIR Afterglow Candidate
  10. GRB 151111A: GROND confirmation of the afterglow and photometric redshift estimate
  11. GRB 151112A: GROND Detection of the Optical/NIR Afterglow Candidate
  12. GRB 151111A: GROND marginal detection of a afterglow candidate
  13. GRB 151111A: Fermi GBM observation
  14. LIGO/Virgo G194575: Liverpool Telescope observations of iPTF-15dld and iPTF-15dni
  15. LIGO/Virgo G194575: La Silla QUEST, Pan-STARRS and PESSTO observations of iPTF15dld
  16. GRB 151107B
  17. GRB 151107A, Swift-BAT refined analysis
  18. GRB 151027A: Hankasalmi optical observations
  19. LIGO/Virgo G194575: INAF-TNG/Asiago Telescope follow-up of iPTF15dld
  20. LIGO/Virgo G194575: INAF-Asiago Telescope further analysis of iPTF candidates
  21. LIGO/Virgo G194575: INAF-Asiago Telescope follow-up of iPTF candidates
  22. LIGO/Virgo G194575: VLA follow-up
  23. GRB 151027A: Mondy optical observations
  24. GRB 151027A: the missing GeV component
  25. GRB 151029A: FRAM optical afterglow detection
  26. GRB 151027A: Correction to GCN 18519
  27. GRB 151031A: GROND observation
  28. LIGO/Virgo G194575: LT Spectroscopy of iPTF candidates
  29. GRB 151031A
  30. GRB 151030A: Fermi GBM observation
  31. LIGO/Virgo G194575: INAF-TNG follow-up of iPTF15dkm and iPTF15dlj
  32. GRB 151029A: MITSuME Ishigakijima upper limits
  33. GRB 151027B: Swift UVOT detection
  34. LIGO/Virgo G194575: VLA follow-up
  35. GRB 151027A: NOT optical and NIR observations
  36. Konus-Wind observation of GRB 151027A
  37. GRB 151027B: RATIR Observations
  38. GRB 151027B: GROND Optical/NIR Afterglow Detection
  39. GRB 151027A: UVOT Observations
  40. GRB 151027A: Early RAPTOR Observations
  41. LIGO/Virgo G194575: MASTER Optical Inspection
  42. GRB 151027A: Fermi GBM observation
  43. GRB 151027A: MITSuME Akeno Optical observation
  44. LIGO/Virgo G194575: Swift observations of LSQ15bjb
  45. LIGO/Virgo G194575: INAF-TNG spectra of LSQ15bjb
  46. LIGO/Virgo G194575: GROND multi-color observations
  47. GRB 151027A: P60 afterglow confirmation and rebrightening
  48. GRB 151027A: KAIT optical afterglow confirmation
  49. LIGO/Virgo G194575: INAF-TNG follow-up of LSQ15bjb
  50. LIGO/Virgo G194575 : La Silla - QUEST followup
  51. GRB 151021A: Skynet PROMPT-CTIO/DSO17 observations of the optical afterglow
  52. GRB 151023A
  53. Possible Fermi-LAT Gamma-ray counterpart for LIGO/Virgo G194575
  54. LIGO/Virgo G194575: LOFAR follow-up
  55. LIGO/Virgo G194575: INTEGRAL search of temporally coincident prompt hard X-ray emission
  56. LIGO/Virgo G194575: more details on transients from Pan-STARRS in the RA=1hr localisation region
  57. LIGO/Virgo G194575: Fermi GBM Observations
  58. LIGO/Virgo G194575: Identification of a GW CBC Candidate
  59. GRB 151022A: Kanata/HOWPol optical observation
  60. GRB 151021B: Fermi GBM detection
  61. Konus-Wind observation of GRB 151021A
  62. GRB 151021A: MITSuME Okayama upper limits
  63. LIGO/Virgo G184098: LOFAR follow-up
  64. GRB 151004A: Swift-XRT follow-up observations
  65. Trigger 659734: Swift detection of SAX J1750.8-2900 or other source near Galactic center
  66. Konus-Wind observation of GRB 151006A
  67. GRB 151006A: Fermi-LAT detection
  68. Konus-Wind observation of GRB 151001B
  69. GRB 151006A: Kanata/HOWPol optical imaging polarimetry
  70. Trigger 657564 / GRB 151004A: Swift BAT and XRT refined analysis
  71. LIGO/Virgo G184098: ongoing Pan-STARRS search for optical transients
  72. GRB 151001A: Fermi GBM detection
  73. LIGO/Virgo G184098: Update to LT Spectroscopy of PS15ccx
  74. LIGO/Virgo G184098: Liverpool Telescope Spectroscopy of PS15ccx
  75. LIGO/Virgo G184098: LOFAR follow-up
  76. LIGO/Virgo G184098: ongoing Pan-STARRS search for optical transients
  77. Konus-Wind observation of GRB 150922A
  78. GRB 150922A: Fermi GBM observation
  79. Konus-Wind observation of GRB 150919A
  80. LIGO/Virgo G184098: INTEGRAL search of temporally coincident prompt hard X-ray emission
  81. ANTARES neutrino detection: Fermi GBM Observations
  82. LIGO/Virgo G184098: DESGW followup program
  83. LIGO/Virgo G184098: TAROT network optical observations
  84. LIGO/Virgo G184098: La Silla - QUEST Followup
  85. LIGO/Virgo G184098: Swift follow-up observations
  86. LIGO/Virgo G184098: DESGW followup program
  87. LIGO/Virgo G184098: Keck II DEIMOS Spectra of iPTF Optical Candidates
  88. LIGO/Virgo G184098: Fermi-GBM ground-based follow-up
  89. LIGO/Virgo G184098: Pan-STARRS1 observations of the northern sky region
  90. LIGO/Virgo G184098: TAROT La Silla Observatory optical observations (TZAC)
  91. Konus-Wind observation of GRB 150911A
  92. GRB150915A : IRSF NIR upper limits
  93. GRB 150915A: NOT observations of a brightening afterglow
  94. GRB 150906B: Further analysis of the Konus-Wind data
  95. GRB 150911A: GROND Upper Limits
  96. GRB 150907A: Swift-XRT afterglow detection
  97. GRB 150910A: MITSuME Ishigakijima Optical Observation after 2 days
  98. GRB 150912A: Fermi GBM observation
  99. GRB 150912A: Swift ToO observations
  100. GRB 150906B: theoretical estimation of redshift and isotropic energy

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