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"

20364 results found.

  1. GRB 110128A: Swift/UVOT observations
  2. GRB 110128A: WHT redshifts of nearby field galaxies
  3. GRB 110128A: Enhanced Swift-XRT position
  4. GRB 110128A: Afterglow detection from NOT
  5. GRB 110128A: TAROT Calern observatory upper limits
  6. GRB 110128A: Swift detection of a burst
  7. GRB 110106B, radio observations
  8. GRB 110120A: MASTER optical observations
  9. IPN triangulation of GRB 110120A
  10. GRB 101225A: CQUEAN optical observation
  11. GRB 110106A: CrAO optical observations
  12. GRB 110112A: optical upper limit
  13. GRB110119: Swift/UVOT Detection
  14. GRB110119A: MITSuME Okayama optical upper limits
  15. GRB 110119A: Swift-BAT refined analysis
  16. GRB 110119A: PAIRITEL NIR Afterglow Detection
  17. GRB 110119A: Enhanced Swift-XRT position
  18. GRB 110119A: Swift detection of a burst with an optical detection
  19. GRB 101219B: tentative redshift and spectroscopic supernova detection
  20. GRB 101219B: GROND detection of a SN signature
  21. Swift-BAT trigger 442771 is a noise fluctuation
  22. GRB 101219B: Likely the GRB host emission dominates now in the uvw2 filter
  23. New feature in Fermi GBM GRB Ground Position Notices
  24. Swift-BAT Trigger 442539 is not a GRB
  25. Swift Trigger 442539 is probably not a GRB
  26. Short GRB 110112B : early optical limit by "Pi of the Sky"
  27. GRB 110112B: Swift XRT and UVOT observations of the INTEGRAL burst
  28. GRB 110112A: MITSuME Akeno and Okayama optical upper limits
  29. GRB 110107A: Swift-XRT afterglow confirmation
  30. GRB 110112A: Swift/UVOT upper limits
  31. GRB 110112A: WHT candidate afterglow/host galaxy
  32. GRB 110112A: Enhanced Swift-XRT position
  33. GRB 110112A: Swift detection of a possible short burst
  34. GRB 110107A: Swift/UVOT upper limits
  35. GRB 101225a
  36. GRB 101219b. Possible radio afterglow detection.
  37. GRB 110107A: Swift-XRT Afterglow Candidate
  38. Short GRB 110106A: MASTER OT observations
  39. GRB 110106A: TNG NIR observations
  40. GRB 110106A: ISAS-Kanazawa optical upper limit
  41. GRB 110106A: MITSuME Okayama optical upper limits
  42. GRB 110106B: Enhanced Swift-XRT position
  43. GRB 110106A: Swift/UVOT Upper Limits
  44. GRB 110106A: Enhanced Swift-XRT position
  45. GRB 110106B: Swift detection of a burst
  46. GRB 110106A: TNG optical observations and candidate counterparts
  47. GRB 110106A: Swift detection of a burst
  48. GRB 101225A: Host galaxy
  49. GRB110102A: Swift/UVOT observations
  50. GRB110102A: MITSuME Okayama Optical Observation
  51. GRB 110102A: Enhanced Swift-XRT position
  52. GRB 110102A: Swift detection of a burst with an optical detection
  53. GRB 101225A: P60 Observations
  54. GRB 101225A: MAXI/GSC observations
  55. GRB 101225A Late-time emission observed by Swift-BAT
  56. GRB 101225A, Swift-BAT refined analysis
  57. GRB 101225A: Swift/UVOT Detection
  58. GRB 101225A: Enhanced Swift-XRT position
  59. Trigger 441015 / GRB 101225A: Further NOT optical observation
  60. Trigger 441015 / GRB 101225A: NOT optical afterglow candidate
  61. GRB 101225A (Swift trigger 441015): optical upper limit
  62. Trigger 441015: Swift detection of a possible burst or transient
  63. GRB 101224A: NOT optical observation
  64. GRB 101224A: Pre-event imaging from DeepSky; Detection of a source in the XRT error circle
  65. GRB 101224A: Swift/UVOT Upper Limits
  66. GRB 101224A: Swift-XRT refined Analysis
  67. GRB101224A: MITSuME Okayama optical upper limits
  68. GRB 101224A - UVOT-enhanced XRT position
  69. GRB 101224A: Swift detection of a short burst
  70. GRB 101219A: Chandra Observations
  71. GRB 101219B: Swift/UVOT refined analysis
  72. GRB 101219B: Enhanced Swift-XRT position
  73. GRB 101219A: MITSuME Ishigakijima Optical upper limits
  74. GRB 101219B: GROND Detection of the Optical/NIR Afterglow
  75. GRB 101219A: IAC80 optical observations
  76. GRB 101219B: Swift detection of a burst with an optical afterglow
  77. GRB 101219A: Swift/UVOT Upper Limits
  78. GRB 101219A: GROND Upper limits
  79. GRB 101219A: Magellan NIR observations
  80. GRB 101219A: Further Gemini-South Imaging
  81. GRB 101219A - NOT observation - upper limit
  82. GRB 101219A: SARA-N Upper Limit
  83. GRB 101219A: REM optical and NIR observations
  84. GRB 101219A: Swift detection of a short hard burst
  85. XRF 101117A, RIMOTS optical upper limits
  86. GRB 101213A: Fermi GBM observation
  87. GRB 101213A: Swift/UVOT Upper Limits
  88. GRB 101213A: Enhanced Swift-XRT position
  89. GRB 101213: object within the X-ray error circle
  90. GRB 101213A: Swift detection of a burst
  91. GRB101204A: Swift/UVOT observations
  92. GRB 101204A: Swift-XRT refined Analysis
  93. GRB101204A GROND Detection of the Optical/NIR Afterglow
  94. GRB 101204A Afterglow Candidate, VATT Observations
  95. GRB 101204A Swift-XRT/UVOT afterglow candidate
  96. GRB 101204A detected in ground analysis of BAT data
  97. GRB101030A
  98. GRB 101201A: Swift-XRT refined Analysis
  99. GRB 101201A: Swift/UVOT Detection
  100. GRB 101201A: GROND Detection of the Optical/NIR Afterglow

Advanced

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