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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').
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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"

43933 results found.

  1. GRB 170121B: AbAO optical observations
  2. LIGO/Virgo G270580: UL50 observations
  3. GRB 170121B: MASTER early optical observations of the Swift possible XT
  4. LIGO/Virgo G270580: CALET Observations
  5. LIGO/Virgo G270580: Pan-STARRS coverage and bright, rising transient PS17yt
  6. GRB 170121B: AstroSat CZTI detection
  7. GRB 170121B: Swift-XRT and UVOT observations
  8. LIGO/Virgo G270580/GW170120 : Asiago observations
  9. GRB 170121B: LCO FTN observations
  10. LIGO/Virgo G268556/GW170104: MAXI/GSC observations
  11. LIGO/Virgo G270580: A third optical transient from CNEOST
  12. GRB 170121B: Fermi GBM detection
  13. GRB 170121B: Swift ToO observations
  14. LIGO/Virgo G270580: ATLAS coverage and 4 optical transients
  15. GRB 170121B/Fermi trigger 506702667 MASTER-Amur OT detection
  16. GRB 170121A: POLAR Observation
  17. GRB 170120A: POLAR Observation
  18. LIGO/Virgo G270580: Fermi-LAT search for a high-energy gamma-ray counterpart
  19. LIGO/Virgo G270580: Two optical counterpart candidates from CNEOST
  20. LIGO/Virgo G270580: INTEGRAL search of temporally coincident prompt hard X-ray
  21. LIGO/Virgo G270580: Swift-XRT sources
  22. LIGO/Virgo G270580: Swift/BAT data search
  23. LIGO/Virgo G268556: Global MASTER Net 21 OTs detection
  24. LIGO/Virgo G270580: Pan-STARRS and ATLAS observations of the skymap
  25. LIGO/Virgo G270580: Observations of initial skymap by Project Mini-GWAC of SVOM
  26. LIGO/Virgo G270580: AGILE MCAL and Super-AGILE Observations
  27. LIGO/Virgo G270580 ANTARES search
  28. LIGO/Virgo G270580: Identification of a GW Burst Candidate
  29. LIGO/Virgo G268556: RATIR Observation of iPTF Candidates
  30. GRB 170117A: Swift/UVOT Upper Limits
  31. GRB 170115B: CALET Gamma-Ray Burst Monitor detection
  32. GRB 170117A: Swift-XRT observations
  33. GRB 170117A: Swift ToO observations
  34. Swift Trigger #733426: possible detection of a burst or transient
  35. GRB 170115A : AbAO optical upper limit
  36. GRB 170115B: Swift-XRT observations
  37. Konus-Wind observation of GRB 170115B
  38. IPN Triangulation of GRB 170115B
  39. GRB 170115B: AGILE detection
  40. LIGO/Virgo G268556: Swift-XRT observations of iPTF17cw
  41. GRB 170112A : AbAO optical observations
  42. GRB 170115A: Swift-BAT refined analysis
  43. GRB 170115A: Swift-XRT refined Analysis
  44. GRB 170114B: POLAR Observation
  45. GRB 170114A: POLAR Observation
  46. GRB 170115B: Tiled Swift observations
  47. GRB 170115B: AstroSat CZTI (Veto) detection
  48. GRB 170115A: Enhanced Swift-XRT position
  49. GRB 170115B: Fermi-LAT detection
  50. GRB 170115B: Fermi GBM detection
  51. GRB 170115A: Swift detection of a burst
  52. GRB 170114A: Fermi GBM detection
  53. GRB 170112B: POLAR observation
  54. LIGO/Virgo G268556: spectra of two nuclear transients PS17fr and PS17er
  55. GRB 170113A: VLT/X-shooter redshift
  56. GRB 170113A: GROND afterglow observations
  57. GRB 170113A: Swift-BAT refined analysis
  58. GRB 170113A: Swift/UVOT Observations
  59. GRB 170113A: Swift-XRT refined Analysis
  60. GRB 161214B: 15 GHz upper limits from AMI
  61. GRB 170113A: Fermi GBM observations
  62. GRB 170113A: Enhanced Swift-XRT position
  63. GRB 170101A: 15 GHz upper limits from AMI
  64. GRB 170113A: LCO Sutherland observations
  65. GRB 161217A: 15 GHz upper limits from AMI
  66. GRB 170113A: Swift detection of a burst with an optical counterpart
  67. LIGO/Virgo G268556: TZAC TAROT network observations with TRE/TCA/TCH
  68. GRB 170112A: RATIR Optical and NIR Observations
  69. GRB 170112A: Swift-BAT refined analysis
  70. GRB 161219B: afterglow and SN2016jca optical observations
  71. GRB 170111A: Swift/UVOT Upper Limits
  72. GRB 170112A: Swift-XRT observations
  73. GRB 170112A: MASTER-OAFA (Argentina) early optical observations
  74. GRB 170112A: REM optical/NIR observations
  75. LIGO/Virgo G268556: Gemini spectra of Pan-STARRS1 transients
  76. GRB 170112A: Swift detection of a short burst
  77. GRB170111A: REM optical/NIR observations
  78. GRB 170111A: Swift-BAT refined analysis
  79. GRB 170111A: SMARTS optical/IR observations
  80. GRB 170111A: Swift-XRT refined Analysis
  81. GRB 161230A: POLAR Observation
  82. LIGO/Virgo G268556: VLA follow-up of iPTF17cw
  83. GRB 170111A: MASTER-OAFA (Argentina) prompt OT observations
  84. LIGO/Virgo G268556/GW170104: Campo Imperatore Observatory observations
  85. LIGO/Virgo G268556: AMI 15 GHz detection of ATLAS17aeu
  86. GRB 170111A: Enhanced Swift-XRT position
  87. GRB 170111A: Swift detection of a burst
  88. LIGO/Virgo G268556: Swift/BAT data search
  89. LIGO/Virgo G268556: Lijiang Observatory GMG Telescope Upper Limit on ATLAS17aeu
  90. LIGO/Virgo G268556: Liverpool Telescope Spectroscopy of iPTF17bv and iPTF17ck
  91. LIGO/Virgo G268556: Spectroscopic observations of ATLAS17aeu and iPTF17cw
  92. GRB 170109A: POLAR Observation
  93. LIGO/Virgo G268556: NOWT of EWE, Xinglong 0.6/0.9m, Xuyi 1m optical upper limits of ATLAS17aeu and a reminder of GCN 20394
  94. LIGO/Virgo G268556/GW170104: TNG observations of ATLAS17aeu
  95. LIGO/Virgo G268556: Swift-XRT confirms that ATLAS17aeu is fading in X-rays
  96. Trigger 731535: Swift detection of GRS 1716-249/GRO J1719-24/V2293 Oph
  97. LIGO/Virgo G268556: ATLAS17aeu position is consistent with GRB170105A
  98. GRB170105A: AstroSat CZTI localisation
  99. LIGO/Virgo G268556: Liverpool Telescope Spectroscopy of iPTF candidates
  100. LIGO/Virgo G268556: Pan-STARRS1 observations and summary of transient sources

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