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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"

43918 results found.

  1. GRB 170121A: POLAR Observation
  2. GRB 170120A: POLAR Observation
  3. LIGO/Virgo G270580: Fermi-LAT search for a high-energy gamma-ray counterpart
  4. LIGO/Virgo G270580: Two optical counterpart candidates from CNEOST
  5. LIGO/Virgo G270580: INTEGRAL search of temporally coincident prompt hard X-ray
  6. LIGO/Virgo G270580: Swift-XRT sources
  7. LIGO/Virgo G270580: Swift/BAT data search
  8. LIGO/Virgo G268556: Global MASTER Net 21 OTs detection
  9. LIGO/Virgo G270580: Pan-STARRS and ATLAS observations of the skymap
  10. LIGO/Virgo G270580: Observations of initial skymap by Project Mini-GWAC of SVOM
  11. LIGO/Virgo G270580: AGILE MCAL and Super-AGILE Observations
  12. LIGO/Virgo G270580 ANTARES search
  13. LIGO/Virgo G270580: Identification of a GW Burst Candidate
  14. LIGO/Virgo G268556: RATIR Observation of iPTF Candidates
  15. GRB 170117A: Swift/UVOT Upper Limits
  16. GRB 170115B: CALET Gamma-Ray Burst Monitor detection
  17. GRB 170117A: Swift-XRT observations
  18. GRB 170117A: Swift ToO observations
  19. Swift Trigger #733426: possible detection of a burst or transient
  20. GRB 170115A : AbAO optical upper limit
  21. GRB 170115B: Swift-XRT observations
  22. Konus-Wind observation of GRB 170115B
  23. IPN Triangulation of GRB 170115B
  24. GRB 170115B: AGILE detection
  25. LIGO/Virgo G268556: Swift-XRT observations of iPTF17cw
  26. GRB 170112A : AbAO optical observations
  27. GRB 170115A: Swift-BAT refined analysis
  28. GRB 170115A: Swift-XRT refined Analysis
  29. GRB 170114B: POLAR Observation
  30. GRB 170114A: POLAR Observation
  31. GRB 170115B: Tiled Swift observations
  32. GRB 170115B: AstroSat CZTI (Veto) detection
  33. GRB 170115A: Enhanced Swift-XRT position
  34. GRB 170115B: Fermi-LAT detection
  35. GRB 170115B: Fermi GBM detection
  36. GRB 170115A: Swift detection of a burst
  37. GRB 170114A: Fermi GBM detection
  38. GRB 170112B: POLAR observation
  39. LIGO/Virgo G268556: spectra of two nuclear transients PS17fr and PS17er
  40. GRB 170113A: VLT/X-shooter redshift
  41. GRB 170113A: GROND afterglow observations
  42. GRB 170113A: Swift-BAT refined analysis
  43. GRB 170113A: Swift/UVOT Observations
  44. GRB 170113A: Swift-XRT refined Analysis
  45. GRB 161214B: 15 GHz upper limits from AMI
  46. GRB 170113A: Fermi GBM observations
  47. GRB 170113A: Enhanced Swift-XRT position
  48. GRB 170101A: 15 GHz upper limits from AMI
  49. GRB 170113A: LCO Sutherland observations
  50. GRB 161217A: 15 GHz upper limits from AMI
  51. GRB 170113A: Swift detection of a burst with an optical counterpart
  52. LIGO/Virgo G268556: TZAC TAROT network observations with TRE/TCA/TCH
  53. GRB 170112A: RATIR Optical and NIR Observations
  54. GRB 170112A: Swift-BAT refined analysis
  55. GRB 161219B: afterglow and SN2016jca optical observations
  56. GRB 170111A: Swift/UVOT Upper Limits
  57. GRB 170112A: Swift-XRT observations
  58. GRB 170112A: MASTER-OAFA (Argentina) early optical observations
  59. GRB 170112A: REM optical/NIR observations
  60. LIGO/Virgo G268556: Gemini spectra of Pan-STARRS1 transients
  61. GRB 170112A: Swift detection of a short burst
  62. GRB170111A: REM optical/NIR observations
  63. GRB 170111A: Swift-BAT refined analysis
  64. GRB 170111A: SMARTS optical/IR observations
  65. GRB 170111A: Swift-XRT refined Analysis
  66. GRB 161230A: POLAR Observation
  67. LIGO/Virgo G268556: VLA follow-up of iPTF17cw
  68. GRB 170111A: MASTER-OAFA (Argentina) prompt OT observations
  69. LIGO/Virgo G268556/GW170104: Campo Imperatore Observatory observations
  70. LIGO/Virgo G268556: AMI 15 GHz detection of ATLAS17aeu
  71. GRB 170111A: Enhanced Swift-XRT position
  72. GRB 170111A: Swift detection of a burst
  73. LIGO/Virgo G268556: Swift/BAT data search
  74. LIGO/Virgo G268556: Lijiang Observatory GMG Telescope Upper Limit on ATLAS17aeu
  75. LIGO/Virgo G268556: Liverpool Telescope Spectroscopy of iPTF17bv and iPTF17ck
  76. LIGO/Virgo G268556: Spectroscopic observations of ATLAS17aeu and iPTF17cw
  77. GRB 170109A: POLAR Observation
  78. LIGO/Virgo G268556: NOWT of EWE, Xinglong 0.6/0.9m, Xuyi 1m optical upper limits of ATLAS17aeu and a reminder of GCN 20394
  79. LIGO/Virgo G268556/GW170104: TNG observations of ATLAS17aeu
  80. LIGO/Virgo G268556: Swift-XRT confirms that ATLAS17aeu is fading in X-rays
  81. Trigger 731535: Swift detection of GRS 1716-249/GRO J1719-24/V2293 Oph
  82. LIGO/Virgo G268556: ATLAS17aeu position is consistent with GRB170105A
  83. GRB170105A: AstroSat CZTI localisation
  84. LIGO/Virgo G268556: Liverpool Telescope Spectroscopy of iPTF candidates
  85. LIGO/Virgo G268556: Pan-STARRS1 observations and summary of transient sources
  86. LIGO/Virgo G268556/GW170104: 10.4m GTC spectroscopic observations of iPTF17fs
  87. LIGO/Virgo G268556/GW170104: TNG spectroscopic observations of iPTF17ck and iPTF17dz
  88. LIGO/Virgo G268556: Gemini spectrum and Pan-STARRS observations of ATLAS17aeu
  89. LIGO/Virgo G268556: IPN Triangulation of GRB 170105A (association with ATLAS17aeu)
  90. Trigger 731257: Another Swift-BAT detection of GRS 1716-249/GRO J1719-24/V2293 Oph
  91. LIGO/Virgo G268556: GWAC_F60B (60cm) follow-up two events of EWE001 and EWE002
  92. Trigger 731183: Swift detection of GRS 1716-249/GRO J1719-24/V2293 Oph
  93. LIGO/Virgo G268556/GW170104: Lomonosov BDRG observations
  94. LIGO/Virgo G268556: Continued iPTF Observations and Additional Optical Transient Candidates
  95. LIGO/Virgo G268556: Swift/UVOT observations of ATLAS17aeu
  96. LIGO/Virgo G268556: CALET Observations
  97. LIGO/Virgo G268556: iPTF Optical Transient Candidates
  98. Discovery Channel Telescope Imaging of ATLAS17aeu (LVCG268556)
  99. LIGO/Virgo G268556: VLA follow-up of ATLAS17aeu
  100. LIGO/Virgo G268556: AGILE-GRID preliminary analysis

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