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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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subject:"Swift"
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21027 results found.

  1. GRB 171011A: MASTER-SAAO optical observations
  2. GRB 171010A: LCO 1m telescope observations
  3. GRB 171010A: Swift-XRT afterglow detection
  4. GRB 171010A: optical observations
  5. GRB 171010A: Swift ToO observations
  6. GRB 171007A: Swift/UVOT Upper Limits
  7. LIGO/Virgo G298048: Mid-Infrared Spitzer/IRAC Observations at 3.6 and 4.5 microns
  8. GRB 171007A: RATIR Optical and NIR Observations
  9. LIGO/Virgo G298048: LWA radio observations
  10. GRB 171004A: Swift/UVOT Upper Limits
  11. LIGO/Virgo G299232: SWASP optical imaging coverage
  12. GRB 171004A: RATIR Optical and NIR Observations
  13. GRB 170710A: LCO Observations
  14. LIGO/Virgo G299232: MAGIC Cherenkov Telescopes observations
  15. Swift Trigger 775946 is a Galactic transient, not GRB 171003
  16. LIGO/Virgo G299232: LOFAR follow-up
  17. GRB 171003A: LT early optical observations
  18. GRB 171003A: Swift detection of a burst or a Galactic Transient
  19. GRB 171001A: RATIR Optical and NIR Observations
  20. GRB 171001A: Nanshan-0.36m optical afterglow detections
  21. GRB 171001A: Swift/UVOT Detection
  22. GRB 171001A: IRSF Observation
  23. GRB 170921A: 15 GHz upper limits from AMI
  24. GRB 170903A: 15 GHz upper limits from AMI
  25. GRB 170906C: 15 GHz upper limits from AMI
  26. GRB 170823A: 15 GHz upper limits from AMI
  27. GRB 170822A: 15 GHz upper limits from AMI
  28. LIGO/VIRGO G299232: AMI-LA Observations of the optical transient Swift J014008.5+343403.6
  29. 3.6m Devasthal Optical Telescope observations of GRB 170428A
  30. Further Swift-XRT observations of IceCube 170922A
  31. LIGO/Virgo G298048: Record of all e-MERLIN results to date on SSS17a
  32. LIGO/Virgo G298048: Further European VLBI Network (EVN) observations of SSS17a
  33. LIGO/Virgo G299232/GW170825: serendipitous XMM-Newton slew observations
  34. LIGO/Virgo G298936/GW170823: serendipitous XMM-Newton slew observations
  35. LIGO/VIRGO G298048: VLA detection of the radio counterpart at 6 GHz
  36. LIGO/VIRGO G298048: Further MeerKAT observations of SSS17a
  37. LIGO/Virgo G298048: Summary of Pi of the Sky observations
  38. IceCube-170922A: Swift-XRT observations
  39. LIGO/VIRGO G298048: Latest 3 GHz Detection of Radio Counterpart to SSS17a
  40. LIGO/Virgo G298048: Limits from further FRB searches of SSS17a
  41. LIGO/Virgo G298048: MWA Observations of Error Region
  42. LIGO/Virgo G298048: Effelsberg 100-m Radio Telescope observations of SSS17a
  43. GRB 170921A: RATIR Optical Afterglow Detection and NIR Observations
  44. LIGO/Virgo G298048: SRT observations of SSS17a in NGC 4993
  45. GRB 170921A: Swift/UVOT Upper Limits
  46. GRB 170921A: LCO 2m telescope observations
  47. GRB 170921A: NOT optical observations
  48. LIGO/Virgo G298048: LCO FLOYDS and Gemini Spectroscopy
  49. GRB 170921A: TAROT Calern observatory optical observations
  50. LIGO/Virgo G298048: ATCA monitoring of SSS17a in NGC 4993
  51. LIGO/Virgo G298048: Limits from an FRB search of SSS17a with the Parkes 64m Radio Telescope
  52. LIGO/Virgo G298048: SSS17a photometry of CHILESCOPE observatory
  53. LIGO/Virgo G298048: Milliarcsecond imaging of the NGC 4993 central radio source
  54. LIGO/Virgo G298048: TOROS photometry of SSS17a
  55. LIGO/Virgo G298048: Desert Fireball Network simultaneous optical observations of the SSS17a/DLT17ck.
  56. LIGO/VIRGO G298048: MeerKAT observations of SSS17a
  57. LIGO/Virgo G297595: NIR Observations following GW170814
  58. LIGO/Virgo G298048: Danish Telescope Observations of SSS17a/DLT17ck
  59. LIGO/Virgo G297595: PIRATE observations
  60. LIGO/Virgo G298048: AST3-2 observations of SSS17a/DLT17ck from Antarctica
  61. LIGO/Virgo G298048: ATCA monitoring of SSS17a in NGC 4993
  62. GRB 170912B: Swift/UVOT Upper Limits
  63. LIGO/Virgo G299232: Khureltogot observations
  64. GRB 170912A: Swift/UVOT Upper-Limits
  65. GRB 170912B: Fermi GBM observations
  66. LIGO/Virgo G298936: Konus-Wind observations
  67. LIGO/Virgo G299232: Konus-Wind observations
  68. LIGO/Virgo G297595: Las Cumbres Observatory Optical Follow-Up
  69. LIGO/Virgo G298048: VLA radio non-detection
  70. LIGO/Virgo G298048: VLBA upper limits at 8.7GHz for the GW counterpart SSS17a/DLT17ck on August 20-21 UT
  71. Swift Triggered on MAXI J1535-571
  72. LIGO/Virgo G298048: LWA Detection
  73. GRB 170906A: Swift/UVOT Detection
  74. GRB 170906B: Swift/UVOT Upper Limits
  75. LIGO/Virgo G299232: Swift-XRT sources
  76. GRB 170906C: optical observations
  77. LIGO/Virgo G298048: ATCA observations of of SSS17a in NGC 4993
  78. GRB 170906C: COATLI Observations
  79. GRB 170906C: Swift/UVOT Upper Limits
  80. LIGO/Virgo G298048 GRAWITA: VST-ESO PARANAL follow up of SSS17a in NGC4993.
  81. GRB 170906A: MASTER-OAFA (Argentina) early automatic OT detection
  82. GRB 170906C: Swift-XRT observations
  83. GRB 170906A: REM optical/NIR observations
  84. LIGO/Virgo G299232: Lulin Observations of Possible OTs
  85. LIGO/VIRGO G298048: Radio detection of SSS17a at 6 GHz with the VLA
  86. LIGO/VIRGO G298048: Radio detection of SSS17a at 3GHz with the VLA/JAGWAR
  87. LIGO/Virgo G299232: Maidanak observations of optical transient SwiftJ014008.5+343403.6
  88. LIGO/Virgo G299232: LOFAR follow-up
  89. Swift Trigger on continued activity of MAXI J1535-571
  90. GRB 170827A: LCO Observations
  91. GRB 170903A: Swift/UVOT Upper Limits
  92. LIGO/Virgo G298048: e-MERLIN upper limits on 5 GHz compact emission from SSS17a
  93. LIGO/Virgo G298048: ATCA monitoring of SSS17a in NGC 4993
  94. LIGO/Virgo G299232: RoboPol observations of MASTER OT J033744.97+723159.0
  95. GRB 170903A: Host galaxy redshift from OSIRIS/GTC
  96. LIGO/Virgo G298048: Chandra X-ray Update on GW170817
  97. GRB 170903A: Swift-XRT observations
  98. LIGO/Virgo G297595: DECam observations of BBH merger region of interest
  99. GRB 170902A: Swift detection of a burst or possible Galactic transient
  100. LIGO/Virgo G298048: Chandra monitoring of the X-ray emission from SSS17a

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