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"

28050 results found.

  1. GRB 110402A: Swift detection of a burst
  2. GRB 110328A / Swift J164449.3+57345: Correction to GCN 11850
  3. GRB 110328A / Swift J164449.3+573451: Radio-optical/NIR Astrometry
  4. GRB 110328A / Swift J164449.3+573451: Mondy optical observations
  5. GRB 110328A / Swift J164449.3+573451: KASINICS K-band Observation
  6. GRB 110328A / Swift J164449.3+573451: X-ray analysis and a mini-blazar analogy
  7. GRB 110328A / Swift J164449.3+573451: PAIRITEL NIR Detection in 2nd Epoch
  8. GRB 110328A / Swift J164449.3+573451: No optical variability of the optical counterpart
  9. GRB 110328A / Swift J164449.3+573451: Konkoly observations
  10. GRB 110328A / Swift J164449.3+573451: LOAO R-band Observation
  11. GRB 110328A / Swift J164449.3+573451: PAIRITEL NIR Upper Limits
  12. GRB 110328A / Swift J164449.3+573451: optical observations
  13. GRB 110328A / Swift J164449.3+573451: EVLA Detection
  14. GRB 110328A / Swift J164449.3+573451: optical spectroscopy from GTC
  15. GRB 110213A, the review of the sky area in plate archives
  16. GRB 110328B: Fermi GBM detection
  17. GRB 110328A / Swift J164449.3+573451: NOT optical observations.
  18. GRB / X-ray transient 110328A: MITSuME OkayamaOptical upper limits
  19. GRB 110328A / Swift J164449.3+573451: PTF Quiescent Optical Counterpart
  20. GRB 110328A: Enhanced Swift-XRT position
  21. GRB 110328A: Swift detection of a burst
  22. GRB 110319B Swift-XRT afterglow confirmation
  23. GRB 110319B BAT refined analysis
  24. GRB 110319B: Swift/UVOT Upper Limits
  25. GRB 110318B: Swift/UVOT Upper Limits
  26. GRB 110319B: GROND upper limits
  27. GRB 110319B: Swift-XRT afterglow candidate.
  28. GRB 110319B found in ground analysis of Swift-BAT data
  29. GRB 110319A: Swift/UVOT Detection
  30. GRB 110319A: Swift-BAT refined analysis
  31. GRB 110319A: Swift-XRT refined Analysis
  32. GRB 110318B: GROND upper limits
  33. GRB 110319A: Enhanced Swift-XRT position
  34. GRB 110319A: Swift detection of a burst
  35. GRB 110318B: Swift-XRT refined Analysis
  36. GRB 110318A: Fermi GBM detection
  37. GRB 110318B: Swift-BAT refined analysis
  38. GRB 110318B: Enhanced Swift-XRT position
  39. GRB 110318A: Swift-BAT refined analysis
  40. GRB 110318B: Swift/UVOT Non-Detection of an Afterglow
  41. GRB 110318B: Swift detection of a burst
  42. GRB 110315A: RTT150 optical observations
  43. GRB 110315A: Swift/UVOT Upper Limits
  44. GRB 110315A: Swift-XRT refined Analysis
  45. GRB 110315A: Swift-BAT refined analysis
  46. GRB 110315A: Enhanced Swift-XRT position
  47. GRB 110315A: MASTER early optical observations
  48. GRB 110315A: Swift detection of a burst
  49. GRB110312A: MITSuME Okayama Optical upper limits
  50. GRB 110312A: RTT150 optical observations
  51. GRB 110312A: Swift/UVOT Upper Limits
  52. GRB 110312A: Swift-XRT refined Analysis
  53. GRB 110312A: GROND Upper Limits
  54. GRB 110312A: Enhanced Swift-XRT position
  55. GRB 110312A: Swift-BAT refined analysis
  56. GRB 110312A: Swift detection of a burst
  57. GRB 110305A: REM detection of a possible NIR afterglow
  58. GRB110305A: MITSuME Ishigakijima Optical upper limits
  59. GRB 110305A: Swift/UVOT Upper Limits
  60. GRB 110305A: Swift-XRT refined Analysis
  61. GRB 110305A: Enhanced Swift-XRT position
  62. GRB 110305A: Swift-BAT refined analysis
  63. GRB 110305A: GROND Detection of Optical Afterglow
  64. GRB 110305A: Swift detection of a burst
  65. GRB 110223A: optical upper limits
  66. GRB 110301A: Fermi GBM detection
  67. Swift/UVOT observations of GRB110223A
  68. No IPN GRB detected in conjunction with candidate GRB 110215
  69. IBAS distribution of coordinates for low significance INTEGRAL GRB triggers
  70. Swift/UVOT observations of GRB110223b
  71. GRB 110223A: Swift-BAT refined analysis
  72. GRB 110223A : early optical limit by "Pi of the Sky"
  73. GRB 110223A: Liverpool Telescope observations
  74. GRB 110223A: Swift-XRT refined Analysis
  75. GRB 110223B: Swift-XRT refined Analysis
  76. GRB 110223A: Enhanced Swift-XRT position
  77. GRB 110223B: Enhanced Swift-XRT position
  78. GRB 110223B: Swift-BAT refined analysis
  79. GRB 110223B: GROND Detection of Optical Afterglow Candidate
  80. GRB 110223B: Swift detection of a burst
  81. GRB 110223A: Swift detection of a burst
  82. GRB 101225A, the review of the sky area in plate archives
  83. OT 110215: Further NIR observations from NOT of the GRB candidate
  84. GRB 110213B: Swift/UVOT observations
  85. Fermi GBM detection of an SGR-like burst
  86. Swift XRT and UVOT Observations of OT 110215
  87. OT 110215: NIR observations from NOT of GRB candidate
  88. GRB 110213A: optical observations in CrAO
  89. GRB 110213B: GROND observations of the optical/NIR afterglow
  90. OT 110215: possible GRB from 2MASS J00264184+8324093
  91. Swift/UVOT observations of GRB110210a.
  92. GRB 110210A: optical upper limit
  93. GRB 110210A: ROVOR Upper Limit
  94. GRB110213A: RAPTOR Early Optical Peak and Plateau Measurements
  95. GRB 110212A: Swift XRT and UVOT observations
  96. GRB 110205A: Konkoly optical observations
  97. GRB 110213B: Swift XRT observation
  98. GRB 110213A: MITSuME Akeno Optical Observation
  99. Konus-Wind observation of GRB 110213B
  100. GRB 110213A: Swift-XRT refined Analysis

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Questions or comments?
Contact GCN directly.
Have you found a bug in GCN?
Open an issue.
Want to contribute code to GCN?
Get involved on GitHub.

gcn.nasa.gov

A service of the Astrophysics Science Division at NASA Goddard Space Flight Center

Looking for U.S. government information and services? Visit USA.gov