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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"

20967 results found.

  1. LIGO/Virgo G268556: Swift/UVOT observations of ATLAS17aeu
  2. LIGO/Virgo G268556: CALET Observations
  3. LIGO/Virgo G268556: iPTF Optical Transient Candidates
  4. Discovery Channel Telescope Imaging of ATLAS17aeu (LVCG268556)
  5. LIGO/Virgo G268556: VLA follow-up of ATLAS17aeu
  6. LIGO/Virgo G268556/GW170104: Global MASTER Net second OT detection
  7. LIGO/Virgo G268556: Swift-XRT detection of ATLAS17aeu
  8. LIGO/Virgo G268556: SWASP optical imaging
  9. LIGO/Virgo G268556/GW170104: Asiago Observations
  10. LIGO/Virgo G268556: Pan-STARRS1 observations of the skymap
  11. LIGO/Virgo G268556/GW170104: Global MASTER Net observations and first OT detection
  12. LIGO/Virgo G268556: ATLAS imaging of the skymap
  13. LIGO/Virgo G268556: DESGW/DECam observations
  14. LIGO/Virgo G268556: AGILE MCAL and Super-AGILE Observations
  15. LIGO/Virgo G268556: Mini-MegaTORTORA follow-up observations
  16. LIGO/Virgo G211117 / GW151226: LOFAR follow-up
  17. LIGO/Virgo G268556: Swift-XRT sources
  18. LIGO/Virgo G268556: observation regions by Project Mini-GWAC of SVOM
  19. LIGO/Virgo G268556: INTEGRAL search of temporally coincident prompt hard X-ray emission
  20. LIGO/Virgo G268556: Fermi GBM Observations
  21. GRB 170101A: POLAR observation
  22. Trigger 729410: Swift detection of V2293 Oph
  23. GRB161219B - Anticipated hyperluminal evidence
  24. GRB 161214B: MASTER-Kislovodsk early optical observations
  25. GMRT radio detection of GRB 161219B
  26. GRB 161214A: MASTER-IAC early optical observations
  27. GRB 161219B: Spectroscopic detection of the associated SN with OSIRIS/GTC
  28. GRB 161224A: TSHAO optical observations
  29. GRB 161224A: Swift/UVOT Upper limits
  30. Trigger 728094, Swift-BAT refined analysis
  31. GRB 161219B: UKIRT near-IR afterglow detection
  32. GRB 161219B: Rapid ALMA Observations & Detection
  33. GRB 161219B: SALT observations
  34. GRB 161219B: VLT/X-shooter redshift
  35. GRB 161214B: optical spectroscopy of the foreground SDSS object
  36. GRB 161202A: 15 GHz upper limits from AMI
  37. GRB 161129A: 15 GHz upper limits from AMI
  38. GRB 161220A: LCO-FTS observations
  39. GRB 161219B: VLA Detection
  40. GRB 161220A: GROND Upper Limits
  41. GRB 161219B: ISON/Terskol optical observations
  42. GRB 161220A: Swift/UVOT Upper Limits
  43. GRB 161219B: Swift/UVOT Detection
  44. GRB 161219B: Watcher optical observations
  45. GRB 161219B: LCO Sutherland observations
  46. GRB 161219B: GROND afterglow observations
  47. GRB 161218A: TAROT Calern observatory optical observations
  48. GRB 161217A: TAROT Calern observatory optical observations
  49. GRB 161218B: POLAR observation
  50. GRB 161218A: POLAR observation
  51. GRB 161217A: Swift/UVOT Upper Limits
  52. GRB 161214B: AbAO and ISON/Terskol optical observations
  53. GRB 161214B: Mondy optical observations
  54. Fermi-LAT Gamma-ray Observations of IceCube-161210
  55. GRB 161214B: Swift/UVOT Afterglow Confirmation
  56. IceCube-161210: Kanata/HONIR near-infrared follow-up observation
  57. GRB 161214B: RATIR Optical and Near-Infrared Observations
  58. GRB 161214B: TAROT Calern observatory optical observations
  59. GRB 161214B: Chante-perdrix observatory optical observations
  60. GRB 161214B: Swift/UVOT Observations
  61. GRB 161214B: NOT optical observations, possible counterpart
  62. GRB 161214A: NOT observations of the afterglow
  63. GRB 161214A: GROND afterglow observations
  64. GRB 161214A: TAROT Calern observatory optical observations
  65. INTEGRAL SPI-ACS and IBIS/Veto observation of IceCube-161210
  66. GRB 161129A: GTC redshift of the likely host galaxy
  67. GRB 161129A: NOT optical observations and candidate host galaxy
  68. GRB 161129A: KWFC z-band photometry
  69. MASTER: Optical Blazar Flare Detection during Fermi trigger 502272781 inspection
  70. GRB 161202A: RATIR Optical and NIR Observations
  71. GRB 161202A: Swift/UVOT Upper Limits
  72. GRB 161129A: Mondy optical observations
  73. GRB 161129A: ISON/UAFO optical observations
  74. GRB 161129A: MITSuME Okayama Ks-band Observation
  75. GRB 160821B: HST detection of the optical and IR counterpart
  76. GRB 161129A: Swift/UVOT Detection
  77. GRB 161129A: Tautenburg Ic-band observations
  78. GRB 161129A: TSHAO optical observations / possible afterglow+host galaxy
  79. GRB 161123A: Swift-XRT observations
  80. GRB 161123A: Tiled Swift observations
  81. GRB 161117A: SMARTS optical/IR afterglow observations
  82. GRB 161119A: MASTER-SAAO possible OT detection during Fermi Alert
  83. GRB 161108A: 15 GHz upper limits from AMI
  84. GRB 161117A: MASTER-OAFA (Argentina) prompt OT observations
  85. GRB 161117A: TAROT La Silla observatory optical observations
  86. GRB 161117A: GMG observation limit
  87. GRB 161117B: Swift/UVOT Upper Limits
  88. GRB 161117A: Swift/UVOT Detection
  89. GRB 161117B: LCO optical observations
  90. GRB161117A: REM optical and NIR afterglow detection
  91. GRB 161113A: Swift/UVOT Upper Limits
  92. GRB 161113A: RATIR Optical and NIR Observations
  93. GRB 161109A: Swift/UVOT Upper Limits
  94. GRB 161104A: Magellan imaging and spectroscopy
  95. GRB 161108A: continued TSHAO optical observations
  96. GRB 161104A: Chandra X-ray observations
  97. GRB 161109A: Swift-XRT observations
  98. GRB 161108A: TSHAO optical observations
  99. GRB 161108A: Swift/UVOT Upper Limits
  100. GRB 161109A: Tiled Swift observations

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