Skip to main content
Updates to LVK & CHIME Notices, Schema v7.2.3! See news and announcements

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').
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"

19565 results found.

  1. GRB 171123A: Swift detection of a burst
  2. GRB 171120A: Xinglong-2.16m optical upper limit
  3. GRB 171120A: Swift/UVOT Upper Limits
  4. GRB 171120A: Enhanced Swift-XRT position
  5. GRB 171120A: Swift detection of a burst
  6. Fermi-LAT Gamma-ray Observations of IceCube-171106A
  7. GRB 171115A: RATIR Optical and NIR Observations
  8. GRB 171115A: Enhanced Swift-XRT position
  9. GRB 171115A: Swift detection of a burst
  10. IPN Triangulation of GRB 171108A (short)
  11. IceCube-171106A: Swift Observations
  12. HAWC follow-up of IceCube-171106A
  13. GRB 171010A: afterglow and SN 2017htp optical observations
  14. GRB 171108A: Fermi GBM detection
  15. INTEGRAL observation of IceCube-171106A
  16. GRB 171010A: possible SN component
  17. GRB 171103A: Swift-BAT refined analysis of a short GRB
  18. GRB 171102B: AbAO optical upper limit
  19. GRB 171102B: TShAO optical upper limit
  20. IPN Triangulation of GRB 171102A
  21. GRB 171102B: Nanshan 0.36m and 0.60m optical upper limits
  22. GRB 171102B: RATIR Optical and NIR Observations
  23. GRB 171102B: Swift/UVOT Upper Limits
  24. GRB 171102B: Enhanced Swift-XRT position
  25. GRB 171102B: Swift detection of a burst
  26. GRB 171030A: Swift non-localization with BAT, XRT and UVOT
  27. GRB 171030A: Swift ToO observations
  28. IPN Triangulation of GRB 171030A (short)
  29. Swift Trigger 783893: KAIT Optical Observations
  30. Swift Triggers 784159 and 784160 are not bursts
  31. Swift Trigger 783893: LCO 1-m telescope observations
  32. Swift Trigger 783893 is probably not a GRB
  33. GRB 171027A: Swift/UVOT Upper Limits
  34. GRB 171027A: Enhanced Swift-XRT position
  35. GRB 171027A: RATIR Confirmation of Fading and Photo-z
  36. GRB 171027A: VLT optical upper limits
  37. GRB 171027A: RATIR Detection of a NIR Afterglow Candidate
  38. GROND observations of GRB 171027A
  39. GRB 171027A: Swift detection of a burst
  40. Swift Trigger 781740 is not a burst
  41. Fermi GBM Observations of IceCube-171015A
  42. GRB 171020A: Continued RATIR Optical and NIR Observation
  43. GRB 171020A: TAROT Calern observatory optical observations
  44. GRB 171020A: Swift/UVOT Upper Limits
  45. GRB 171020A: RATIR Optical and NIR Observations
  46. GRB 171020A: Enhanced Swift-XRT position
  47. GRB 171020A: Confirmation of OT fading
  48. GRB 171020A: Mini-MegaTORTORA upper limits on simultaneous optical emission
  49. GRB 171020A: NOT optical afterglow detection
  50. GRB 171020A: Swift detection of a burst
  51. Swift Trigger on AXP CXOU J164710.2-455216/PSR J1647-4552
  52. GRB 171010B: Swift-XRT afterglow detection
  53. Trigger 779762: Swift detection of Vela X-1
  54. Trigger 779351: Swift detection of Swift J0243.6+6124
  55. INTEGRAL SPI-ACS observation of IceCube-171015A
  56. Swift trigger 779171 is probably a noise fluctuation
  57. GRB 171010A : Optical observations from HCT
  58. GRB 171010A: RATIR Optical and NIR Observations
  59. BAT trigger 778435 is not a GRB.
  60. GRB 171013A: TAROT Calern observatory optical observations
  61. GRB 171013A: Swift detection of a possible burst
  62. GRB 171010A: Swift/UVOT Detection
  63. Konus-Wind observation of GRB 171010A
  64. IPN Triangulation of GRB 171011B (long/very bright)
  65. GRB 171010B: Swift ToO observations
  66. GRB 171011A: TAROT Calern observatory optical observations
  67. GRB 171010A: Swift-XRT afterglow detection
  68. GRB 171010A: optical observations
  69. GRB 171010A: OT, spectrum, and possible host galaxy
  70. GRB 171010A: Swift ToO observations
  71. GRB 171010A: Fermi-LAT detection
  72. GRB 171007A: Swift/UVOT Upper Limits
  73. LIGO/Virgo G298048/GW170817: updated localization from parameter estimation
  74. GRB 171007A: Enhanced Swift-XRT position
  75. GRB 171007A: Swift-XRT refined Analysis
  76. GRB 171007A: RATIR Optical and NIR Observations
  77. GRB 171007A: Swift detection of a burst
  78. LIGO/Virgo G298048: LWA radio observations
  79. GRB 171004A: Swift/UVOT Upper Limits
  80. GRB 171004A: Enhanced Swift-XRT position
  81. GRB 171004A: RATIR Optical and NIR Observations
  82. GRB 170710A: LCO Observations
  83. GRB 171004A: Swift detection of a burst
  84. GRB 171003A: Enhanced Swift-XRT position
  85. LIGO/Virgo G299232: MAGIC Cherenkov Telescopes observations
  86. LIGO/Virgo G299232: LOFAR follow-up
  87. GRB 171003A: LT early optical observations
  88. GRB 171003A: Swift detection of a burst or a Galactic Transient
  89. GRB 171001A: RATIR Optical and NIR Observations
  90. GRB 171001A: Nanshan-0.36m optical afterglow detections
  91. GRB 171001A: Swift/UVOT Detection
  92. GRB 171001A: IRSF Observation
  93. GRB171001A: D50 optical limit
  94. GRB 171001A: Enhanced Swift-XRT position
  95. GRB 171001A: Swift detection of a burst
  96. GRB 170728B: Kottamia R-band observation
  97. LIGO/Virgo G298048: Summary of Pi of the Sky observations
  98. IceCube-170922A: Swift-XRT observations
  99. LIGO/Virgo G298048: MWA Observations of Error Region
  100. IceCube-170922A: HAWC follow-up

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Looking for U.S. government information and services? Visit USA.gov