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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').
Advanced Search

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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

19663 results found.

  1. GRB 171027A: Swift detection of a burst
  2. Swift trigger 781740: Further analysis from Swift and Fermi/GBM
  3. Numerous Fermi-GBM Subthreshold Notices are due to Swift J0243.6+6
  4. GRB 171022A: Fermi-LAT detection
  5. Swift Trigger 781740 is not a burst
  6. GRB 171020A: TAROT Calern observatory optical observations
  7. GRB 171020A: Swift/UVOT Upper Limits
  8. GRB 171020A: Swift-BAT refined analysis
  9. GRB 171020A: Swift-XRT refined Analysis
  10. GRB 171020A: Enhanced Swift-XRT position
  11. GRB 171020A: LT observations
  12. GRB 171020A: Mini-MegaTORTORA upper limits on simultaneous optical emission
  13. GRB 171020A: Swift detection of a burst
  14. Fermi-GBM Detection of possible burst from AXP CXOU J164710.2-455216/PSR J1647-4552
  15. Trigger 780207: Swift triggers again on AXP CXOU J164710.2-455216/PSR J1647-4552
  16. Swift Trigger on AXP CXOU J164710.2-455216/PSR J1647-4552
  17. GRB 171010B: Swift-XRT afterglow detection
  18. Trigger 779762: Swift detection of Vela X-1
  19. Trigger 779351: Swift detection of Swift J0243.6+6124
  20. Swift trigger 779171 is probably a noise fluctuation
  21. GRB 171010A: VLA Detection
  22. BAT trigger 778435 is not a GRB.
  23. GRB 171010B: Swift-XRT observations
  24. GRB 171013A: TAROT Calern observatory optical observations
  25. GRB 171013A: Swift detection of a possible burst
  26. GRB 171011A: Swift-BAT refined analysis
  27. GRB 171010A: Swift/UVOT Detection
  28. GRB 171010B: Fermi GBM detection
  29. IPN Triangulation of GRB 171011B (long/very bright)
  30. GRB 171010B: Swift ToO observations
  31. GRB 171011A: TAROT Calern observatory optical observations
  32. GRB 171010B: Swift detection of a burst
  33. GRB 171011A: MASTER-SAAO optical observations
  34. GRB 171011A: Swift detection of a burst
  35. GRB 171010A: Fermi GBM observation
  36. GRB 171010A: LCO 1m telescope observations
  37. GRB 171010A: Swift-XRT afterglow detection
  38. GRB 171010A: OT, spectrum, and possible host galaxy
  39. GRB 171010A: Swift ToO observations
  40. GRB 171010A: Fermi-LAT detection
  41. GRB 171007A: Swift/UVOT Upper Limits
  42. GRB 171007A: Swift-BAT refined analysis
  43. GRB 171007A: Fermi GBM observation
  44. GRB 171007A: Enhanced Swift-XRT position
  45. GRB 171007A: Swift-XRT refined Analysis
  46. GRB 171007A: RATIR Optical and NIR Observations
  47. GRB 171007A: Swift detection of a burst
  48. GRB 171004A: Swift/UVOT Upper Limits
  49. GRB 171004A: Swift-BAT refined analysis
  50. GRB 171004A: Swift-XRT refined Analysis
  51. GRB 171004A: Enhanced Swift-XRT position
  52. LIGO/Virgo G299232: SWASP optical imaging coverage
  53. GRB 171004A: RATIR Optical and NIR Observations
  54. GRB 171004A: Swift detection of a burst
  55. GRB 171003A: Enhanced Swift-XRT position
  56. LIGO/Virgo G299232: MAGIC Cherenkov Telescopes observations
  57. Swift Trigger 775946 is a Galactic transient, not GRB 171003
  58. LIGO/Virgo G299232: LOFAR follow-up
  59. GRB 171003A: LT early optical observations
  60. GRB 171003A: Swift detection of a burst or a Galactic Transient
  61. GRB 171001A: Swift-BAT refined analysis
  62. GRB 171001A: Swift-XRT refined Analysis
  63. GRB 171001A: Swift/UVOT Detection
  64. GRB171001A: D50 optical limit
  65. GRB 171001A: Enhanced Swift-XRT position
  66. GRB 170921A: 15 GHz upper limits from AMI
  67. GRB 170903A: 15 GHz upper limits from AMI
  68. GRB 170906C: 15 GHz upper limits from AMI
  69. GRB 170823A: 15 GHz upper limits from AMI
  70. GRB 170822A: 15 GHz upper limits from AMI
  71. GRB 171001A: Swift detection of a burst
  72. LIGO/VIRGO G299232: AMI-LA Observations of the optical transient Swift J014008.5+343403.6
  73. 3.6m Devasthal Optical Telescope observations of GRB 170428A
  74. Further Swift-XRT observations of IceCube 170922A
  75. LIGO/Virgo G299232/GW170825: serendipitous XMM-Newton slew observations
  76. LIGO/Virgo G298936/GW170823: serendipitous XMM-Newton slew observations
  77. IceCube-170922A: Swift-XRT observations
  78. Correction to GCN Circular 21919: GRB 170921C: Insight-HXMT detection
  79. GRB 170906A: Insight-HXMT detection
  80. IPN Triangulation of GRB 170921B
  81. GRB 170921A: RATIR Optical Afterglow Detection and NIR Observations
  82. GRB 170921A: Swift/UVOT Upper Limits
  83. GRB 170921A: Swift-BAT refined analysis
  84. GRB 170921A: LCO 2m telescope observations
  85. GRB 170921A: Enhanced Swift-XRT position
  86. GRB 170921A: Swift-XRT refined Analysis
  87. GRB 170921A: TAROT Calern observatory optical observations
  88. GRB 170921A: Swift detection of a burst
  89. LIGO/Virgo G298048: ATCA monitoring of SSS17a in NGC 4993
  90. Swift trigger 773082 is probably not astrophysical
  91. LIGO/Virgo G298048: ATCA monitoring of SSS17a in NGC 4993
  92. GRB 170912B: Swift/UVOT Upper Limits
  93. GRB 170912B: Swift-BAT refined analysis
  94. GRB 170912A: Swift-BAT refined analysis
  95. GRB 170912A: Swift-XRT refined Analysis
  96. GRB 170912A: Swift/UVOT Upper-Limits
  97. GRB 170912B: Swift-XRT refined Analysis
  98. GRB 170912B: Fermi GBM observations
  99. GRB 170912B: Enhanced Swift-XRT position
  100. GRB 170912B: Swift detection of a burst

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