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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"

20983 results found.

  1. LIGO/Virgo G268556: Additional GROWTH follow up observation of iPTF Optical Transient Candidates
  2. LIGO/Virgo G268556: VLA follow-up of iPTF17cw
  3. GRB 170111A: MASTER-OAFA (Argentina) prompt OT observations
  4. LIGO/Virgo G268556/GW170104: Campo Imperatore Observatory observations
  5. LIGO/Virgo G268556: Spectroscopic observations of ATLAS17aeu and iPTF17cw
  6. LIGO/Virgo G268556: NOWT of EWE, Xinglong 0.6/0.9m, Xuyi 1m optical upper limits of ATLAS17aeu and a reminder of GCN 20394
  7. LIGO/Virgo G268556/GW170104: TNG observations of ATLAS17aeu
  8. LIGO/Virgo G268556: Swift-XRT confirms that ATLAS17aeu is fading in X-rays
  9. Trigger 731535: Swift detection of GRS 1716-249/GRO J1719-24/V2293 Oph
  10. LIGO/Virgo G268556: Pan-STARRS1 observations and summary of transient sources
  11. LIGO/Virgo G268556/GW170104: 10.4m GTC spectroscopic observations of iPTF17fs
  12. LIGO/Virgo G268556/GW170104: TNG spectroscopic observations of iPTF17ck and iPTF17dz
  13. LIGO/Virgo G268556: Gemini spectrum and Pan-STARRS observations of ATLAS17aeu
  14. Trigger 731183: Swift detection of GRS 1716-249/GRO J1719-24/V2293 Oph
  15. LIGO/Virgo G268556/GW170104: Lomonosov BDRG observations
  16. LIGO/Virgo G268556: Continued iPTF Observations and Additional Optical Transient Candidates
  17. LIGO/Virgo G268556: Swift/UVOT observations of ATLAS17aeu
  18. LIGO/Virgo G268556: CALET Observations
  19. LIGO/Virgo G268556: iPTF Optical Transient Candidates
  20. Discovery Channel Telescope Imaging of ATLAS17aeu (LVCG268556)
  21. LIGO/Virgo G268556: VLA follow-up of ATLAS17aeu
  22. LIGO/Virgo G268556/GW170104: Global MASTER Net second OT detection
  23. LIGO/Virgo G268556: Swift-XRT detection of ATLAS17aeu
  24. LIGO/Virgo G268556: SWASP optical imaging
  25. LIGO/Virgo G268556/GW170104: Asiago Observations
  26. LIGO/Virgo G268556: Pan-STARRS1 observations of the skymap
  27. LIGO/Virgo G268556/GW170104: Global MASTER Net observations and first OT detection
  28. LIGO/Virgo G268556: ATLAS imaging of the skymap
  29. LIGO/Virgo G268556: DESGW/DECam observations
  30. LIGO/Virgo G268556: AGILE MCAL and Super-AGILE Observations
  31. LIGO/Virgo G268556: Mini-MegaTORTORA follow-up observations
  32. LIGO/Virgo G211117 / GW151226: LOFAR follow-up
  33. LIGO/Virgo G268556: Swift-XRT sources
  34. LIGO/Virgo G268556: observation regions by Project Mini-GWAC of SVOM
  35. LIGO/Virgo G268556: INTEGRAL search of temporally coincident prompt hard X-ray emission
  36. LIGO/Virgo G268556: Fermi GBM Observations
  37. GRB 170101A: POLAR observation
  38. Trigger 729410: Swift detection of V2293 Oph
  39. GRB161219B - Anticipated hyperluminal evidence
  40. GRB 161214B: MASTER-Kislovodsk early optical observations
  41. GMRT radio detection of GRB 161219B
  42. GRB 161214A: MASTER-IAC early optical observations
  43. GRB 161219B: Spectroscopic detection of the associated SN with OSIRIS/GTC
  44. GRB 161224A: TSHAO optical observations
  45. GRB 161224A: Swift/UVOT Upper limits
  46. Trigger 728094, Swift-BAT refined analysis
  47. GRB 161219B: UKIRT near-IR afterglow detection
  48. GRB 161219B: Rapid ALMA Observations & Detection
  49. GRB 161219B: SALT observations
  50. GRB 161219B: VLT/X-shooter redshift
  51. GRB 161214B: optical spectroscopy of the foreground SDSS object
  52. GRB 161202A: 15 GHz upper limits from AMI
  53. GRB 161129A: 15 GHz upper limits from AMI
  54. GRB 161220A: LCO-FTS observations
  55. GRB 161219B: VLA Detection
  56. GRB 161220A: GROND Upper Limits
  57. GRB 161219B: ISON/Terskol optical observations
  58. GRB 161220A: Swift/UVOT Upper Limits
  59. GRB 161219B: Swift/UVOT Detection
  60. GRB 161219B: Watcher optical observations
  61. GRB 161219B: LCO Sutherland observations
  62. GRB 161219B: GROND afterglow observations
  63. GRB 161218A: TAROT Calern observatory optical observations
  64. GRB 161217A: TAROT Calern observatory optical observations
  65. GRB 161218B: POLAR observation
  66. GRB 161218A: POLAR observation
  67. GRB 161217A: Swift/UVOT Upper Limits
  68. GRB 161214B: AbAO and ISON/Terskol optical observations
  69. GRB 161214B: Mondy optical observations
  70. Fermi-LAT Gamma-ray Observations of IceCube-161210
  71. GRB 161214B: Swift/UVOT Afterglow Confirmation
  72. IceCube-161210: Kanata/HONIR near-infrared follow-up observation
  73. GRB 161214B: RATIR Optical and Near-Infrared Observations
  74. GRB 161214B: TAROT Calern observatory optical observations
  75. GRB 161214B: Chante-perdrix observatory optical observations
  76. GRB 161214B: Swift/UVOT Observations
  77. GRB 161214B: NOT optical observations, possible counterpart
  78. GRB 161214A: NOT observations of the afterglow
  79. GRB 161214A: GROND afterglow observations
  80. GRB 161214A: TAROT Calern observatory optical observations
  81. INTEGRAL SPI-ACS and IBIS/Veto observation of IceCube-161210
  82. GRB 161129A: GTC redshift of the likely host galaxy
  83. GRB 161129A: NOT optical observations and candidate host galaxy
  84. GRB 161129A: KWFC z-band photometry
  85. MASTER: Optical Blazar Flare Detection during Fermi trigger 502272781 inspection
  86. GRB 161202A: RATIR Optical and NIR Observations
  87. GRB 161202A: Swift/UVOT Upper Limits
  88. GRB 161129A: Mondy optical observations
  89. GRB 161129A: ISON/UAFO optical observations
  90. GRB 161129A: MITSuME Okayama Ks-band Observation
  91. GRB 160821B: HST detection of the optical and IR counterpart
  92. GRB 161129A: Swift/UVOT Detection
  93. GRB 161129A: Tautenburg Ic-band observations
  94. GRB 161129A: TSHAO optical observations / possible afterglow+host galaxy
  95. GRB 161123A: Swift-XRT observations
  96. GRB 161123A: Tiled Swift observations
  97. GRB 161117A: SMARTS optical/IR afterglow observations
  98. GRB 161119A: MASTER-SAAO possible OT detection during Fermi Alert
  99. GRB 161108A: 15 GHz upper limits from AMI
  100. GRB 161117A: MASTER-OAFA (Argentina) prompt OT observations

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