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"

12321 results found.

  1. Swift observations of the X-ray transient in NGC 2770 (aka SN2008D)
  2. Refined Swift-XRT analysis of the transient in NGC 2770
  3. Refined Swift UVOT Analysis of SN 2008D (Transient in NGC 2770)
  4. GRB071227: Swift/UVOT refined analysis
  5. GRB 071227: REM NIR and Optical observations
  6. GRB 071227: Swift detection of a burst
  7. GRB 070429B: Possible UVOT Detection of an Optical Afterglow
  8. GRB071122: Swift/UVOT Observations
  9. GRB 071122: Swift detection of a burst
  10. GRB 071118: P60 Observations
  11. GRB 071117: VLT observations and probable redshift
  12. Swift/UVOT observations of GRB071118
  13. Swift XRT follow-up observations of GRB071008
  14. Swift/UVOT upper limits for GRB 071117
  15. GRB 071118: Swift detection of a burst
  16. VLT FORS2 observations of short hard GRB071112B
  17. GRB 071117: Initial Swift/UVOT observations
  18. Swift detection of MXB 0656-072
  19. VLA radio upper limit on GRB 071112C
  20. GRB 071112C: Optical and NIR data observed with KANATA
  21. GRB 071112C: SARA upper limit
  22. GRB 071112C: Swift/UVOT observations
  23. Swift UVOT upper limits of GRB071112B
  24. GRB 071112B: Swift-XRT preliminary analysis
  25. Swift XRT follow-up observations of GRB071028B
  26. GRB071109: Super-LOTIS observations
  27. Swift/UVOT initial analysis of GRB071109
  28. GRB 071109: further Swift-XRT analysis
  29. GRB 071104: Swift-XRT Team Refined Analysis
  30. Swift XRT and UVOT observations of GRB071028B
  31. GRB071101: Optical and NIR upper limits by KANATA
  32. GRB071101 LOAO B,V,R,I observation
  33. GRB 071101: Swift detection of a burst
  34. GRB 071031: Swift/UVOT detection of afterglow
  35. GRB 071020: MITSuME Akeno optical observations
  36. GRB 071031: REM NIR and Optical observation
  37. GRB071025: Optical+NIR observations
  38. Swift UVOT upper limits to GRB071028
  39. GRB071028: Xinglong EST V-band upper limit
  40. GRB071021: MARGE Optical Limits
  41. GRB071020, optical upper limit
  42. GRB 071025: SARA VRI upper limits
  43. GRB 071025 Milagro GeV/TeV Observations
  44. Swift UVOT upper limits
  45. GRB071025: Xinglong TNT I-band upper limit
  46. GRB 060602A: host redshift
  47. GRB 071025: Early Super-LOTIS Observations
  48. GRB 071025: ROTSE-III Refined Analysis
  49. GRB 071025: Swift detection of a burst
  50. GRB071021: Optical+NIR observations
  51. GRB 071021: (Relatively shallow) IR non-detections; motivation for optical spectroscopy
  52. GRB071021: MITSuME Okayama Optical Upper Limits
  53. GRB 071021: Xinglong TNT optical Upper Limit
  54. Konus-Wind observation of GRB 071020
  55. GRB 071017 - Swift XRT observations
  56. GRB 071013: TLS Upper Limit
  57. GRB 20071013: Xinglong TNT optical Upper Limit
  58. GRB 071011: Optical Limit after 13.95hrs
  59. GRB 071011: Kanazawa Optical limits
  60. GRB 071010B: Super-LOTIS upper limit
  61. GRB 071010B: Keck/LRIS Spectroscopy
  62. GRB 071010: Keck/LRIS Spectroscopy
  63. GRB070920A: MAGIC telescope GeV observation
  64. GRB 070810B: further XRT analysis
  65. GRB 071003: Keck HIRES spectroscopy
  66. VLA observation of GRB 070923
  67. GRB 070917: MITSuME Akeno Ic upper limit
  68. GRB 070917: R band observations
  69. IPN search for a GRB associated with TAROT transient on August 31
  70. GRB 070731: Swift/UVOT Upper Limit
  71. GRB070810B: Swift/UVOT Upper Limits
  72. GRB 070809: Swift/UVOT Corrected Photometry
  73. GRB 070810B: Xinglong TNT optical Upper Limit
  74. GRB 070809: Swift/UVOT Upper Limits
  75. GRB 070810B: Swift detection of a short burst
  76. VLA upper limit on the short hard burst GRB 070729
  77. GRB 070810: Swift detection of a burst
  78. GRB 070808: Swift/UVOT upper limits
  79. GRB 070808: OPTIMA-Burst optical upper limit
  80. GRB 070808: Xinglong TNT optical Upper Limit
  81. GRB 070808: Swift detection of a burst
  82. GRB070612A: Radio upper limit from GMRT
  83. Swift/UVOT observations of GRB070805
  84. GRB 070805: Swift XRT initial analysis.
  85. GRB 070805: Swift/UVOT initial analysis
  86. UVOT observations of SAXJ1810.8-2609
  87. GRB070802: Swift/UVOT upper limits
  88. GRB 070802: Swift detection of a burst
  89. Swift/UVOT detection of GRB070714B
  90. VLA upper limit on short hard burst GRB 070714B
  91. GRB070729: Swift/UVOT upper limits
  92. GRB 070729: Swift-XRT refined analysis
  93. GRB 070729: Swift detection of a short hard burst
  94. GRB 070724B: Swift/UVOT Upper limits
  95. Swift/UVOT refined analysis of GRB070724
  96. GRB 070724: Swift detection of a burst
  97. Swift/UVOT observations of GRB070721B optical afterglow.
  98. Swift/UVOT Observations of GRB070721A
  99. GRB 070721B : Faulkes Telescope South observations
  100. GRB 070721A : Faulkes Telescope South optical limit

Advanced

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