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"

2797 results found.

  1. IPN triangulation of GRB 110820B (very long duration, extremely intense)
  2. IPN triangulation of GRB110802A (short/hard burst)
  3. GRB 110715A optical observations
  4. Swift Trigger 457076: a possible GRB
  5. GRB 110708A: Konkoly observations
  6. GRB 110709B: Swift/UVOT Detection of Possible Optical Flaring
  7. GRB 110709B : A possible source in USNO B 1.0
  8. GRB 110709B: possible quiescent source in DSS
  9. GRB 110708A: Liverpool Telescope observations
  10. GRB 110708A: Lick observations
  11. GRB 110625A, the review of the sky area in plate archives
  12. Swift Trigger 456659 is probably not astrophysical
  13. GRB 110625A: 1.23m CAHA I-band observations
  14. IPN triangulation of GRB110618A (long duration, extremely intense)
  15. GRB 110604A: Suzaku WAM observation of the prompt emission
  16. GRB 110530A: optical observations in Mondy observatory
  17. GMRT detection of GRB 110328A
  18. GRB 110503A optical observation
  19. GRB 110503A optical observations
  20. GRB 110428A : Swift-XRT observations
  21. GRB 110422A: correction to the GCN circ. 11958
  22. GRB 110414A: GROND upper limits
  23. GRB 100407A : Errata of afterglow position in GCN 11899
  24. GRB 110406A: An exceptionally bright burst detected by INTEGRAL SPI-ACS
  25. GRB110328A/Swift J164449.3+573451: Fermi LAT Observations
  26. GRB 110328A / Swift J164449.3+573451: BAT refined analysis
  27. GRB 110213A, the review of the sky area in plate archives
  28. GRB 110328A / Swift J164449.3+573451: NOT optical observations.
  29. GRB 110318B: Swift detection of a burst
  30. GRB 110305A: REM detection of a possible NIR afterglow
  31. IBAS distribution of coordinates for low significance INTEGRAL GRB triggers
  32. GRB 101225A, the review of the sky area in plate archives
  33. OT 110215: possible GRB from 2MASS J00264184+8324093
  34. GRB 110213B: Possible Host Galaxy in SDSS Stripe 82 Imaging
  35. GRB 110213B: P60 Optical Afterglow Candidate
  36. GRB 110206A: SMARTS optical/IR afterglow candidate observations
  37. GRB 101225A is likely at z~0
  38. GRB 110205A: Possible Lick/Kast redshift
  39. GRB 101224A, the review of the sky area in plate archives
  40. GRB 101219B: GROND detection of a SN signature
  41. GRB 101219B: correction
  42. New feature in Fermi GBM GRB Ground Position Notices
  43. GRB 110112A: WHT candidate afterglow/host galaxy
  44. GRB 110112A: Swift detection of a possible short burst
  45. GRB 101219b. Possible radio afterglow detection.
  46. GRB 110106B: Gemini-North / WHT detection of a fading afterglow
  47. GRB 101225: Optical follow-up of the Christmas burst
  48. GRB 101225A: Swift-XRT refined Analysis
  49. Trigger 441015: Swift detection of a possible burst or transient
  50. GRB 101224A: Swift detection of a short burst
  51. Redshift solution(s) for GRB101213A from Swift-XRT data
  52. GRB 101204A Afterglow Candidate, VATT Observations
  53. IPN Localization of GRB101130 (possible short duration burst)
  54. GRB101030A
  55. Optical observation of GRB 101024A
  56. GRB 101117B: Swift-BAT refined analysis
  57. Possible detection of INTEGRAL burst GRB 101112A by the EVLA
  58. GRB 090113, the review of the sky area in plate archives
  59. GRB 101030A: Swift-BAT refined analysis
  60. GRB 101030A: Swift detection of a burst
  61. GRB 090111, the review of the sky area in plate archives (1976-1996)
  62. GRB 101008A: correction to the GCN 11352
  63. GRB 101017A: Swift detection of a burst with optical counterpart
  64. GRB 101011A: Swift/UVOT Observations of a Possible Optical Afterglow
  65. GRB 101008A: MASTER prompt optical observations
  66. GRB 101008A: SAO RAS optical observations
  67. GRB 100924A: Fermi GBM observation
  68. GRB 100925A / MAXI J1659-152: Optical observation with the Kottamia 188cm telescope
  69. GRB 100925A/MAXI J1659-152: Submm observations from APEX
  70. GRB 100915A: Correction to Swift-BAT refined analysis
  71. GRB 100901A: errata of GRB name in GCN 11270
  72. GRB 100905A: UKIRT zJHK Observation
  73. GRB 100901A: Possible WSRT Radio Detection
  74. Optical observations of GRB 100901A
  75. GRB 100902A: GROND observations; afterglow candidate
  76. GRB 100901A: optical observation at Mt.Terskol
  77. GRB 100816A: 10.4-m GTC redshift confirmation
  78. GRB 100816A: VLT and Gemini-N revised redshift
  79. GRB 100816A : Lulin r'-band observation
  80. GRB 100816A: Swift detection of a possibly short burst with optical afterglow
  81. GRB 100805A: the 4-th epoch of SAO RAS optical observations
  82. GRB 100805A: Swift/UVOT Observations of a Possible Late-Time Brightening
  83. GRB 100805A: Swift-BAT refined analysis
  84. Trigger 430975: Swift detection of a possible burst
  85. GRB 100802A: Swift/UVOT Possible Optical Afterglow
  86. GRB 100802A: Liverpool Telescope observations
  87. GRB 100802A: Possible Swift/UVOT Detection of Optical Afterglow
  88. GRB 100728A, Swift-BAT refined analysis
  89. GRB 100728B: Swift detection of a burst with an optical counterpart
  90. GRB 100727A: Swift detection of a burst
  91. GRB 100725B: refined XRT analysis
  92. GRB 100713A: optical observation in Maidanak
  93. GRB 100628A: Keck/LRIS Spectroscopy of Host Galaxy Candidate
  94. GRB 100628A: Near-IR sources coincident with the possible X-ray afterglow
  95. GRB 100628A: Swift XRT/UVOT refined analysis
  96. GRB 100615A: Additional Gemini/NIRI observations
  97. GRB 100702A, Swift-BAT refined analysis
  98. GRB 100628A: GROND optical/NIR observations of the host candidate
  99. GRB100625A: GROND confirmation of constant source
  100. GRB100628A: RTT150 optical observations

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