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"

45448 results found.

  1. IPN localization of GRB000429
  2. GRB 000418, UBVRI field photometry
  3. GRB000418, Radio detection
  4. GRB000418, K'-band photometry
  5. GRB 000418, Optical Observation
  6. GRB 000418, optical observation
  7. GRB000424 Optical Observations
  8. GRB 000418, Optical Observation
  9. GRB000424, optical observations
  10. GRB000424, optical observations
  11. GRB 000424, Optical Observations
  12. GRB 000418, Optical Observation
  13. GRB000418, near-infrared observations
  14. BeppoSAX GRB000424
  15. Correction to IPN error box for GRB000419
  16. IPN error box for GRB000418
  17. GRB000419 [IPN Position]
  18. GRB000416 Optical Observations
  19. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  20. GRB000416 BRJK observations
  21. 1SAXJ1715.0-7134 refined position
  22. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  23. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  24. Budget cuts in BeppoSAX operations: impact on GRB observations
  25. GRB 000408, optical observations
  26. Refined IPN error box for GRB000408
  27. GRB 991208, UBVRI field photometry
  28. GRB000301c results
  29. GRB000408: Optical CCD Observations from MIRO
  30. GRB000408, lotis optical observations
  31. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  32. GRB000408 [IPN Position]
  33. GRB000326 Optical Observations
  34. GRB000301C - Addendum to GCN 623
  35. GRB000301C - R magnitude lower limit
  36. GRB000326, Further VLA observations
  37. GRB 000323, optical observations
  38. GRB 000326: Optical Observations
  39. GRB000326, Radio observations
  40. GRB000326 [IPN Position]
  41. GRB 000307 optical observations
  42. GRB000323 [IPN Position]
  43. Single error box for GRB000315
  44. GRB000315 [IPN Positions]
  45. GRB000313, Radio observations
  46. GRB 000313 - optical transient in the BATSE error box
  47. GRB000301C - B and R photometry
  48. GRB000301C - R photometry
  49. GRB 000307, Optical Observations
  50. GRB 000307, BVRI Field Photometry
  51. GRB 000301C: Optical Spectrum and Redshift
  52. GRB 000301C: Optical Spectrum and Redshift
  53. GRB 000301C: A Precise Redshift Determination
  54. GRB 000301C, Optical Observation
  55. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  56. GRB 000301C: HST/STIS CCD Imaging of the field
  57. IPN error box for GRB000307
  58. GRB 000301c: K' observations
  59. GRB000301C, optical R-band observations
  60. GRB000301c - R photometry and nearby faint source confirmation
  61. GRB 000301C, Optical Observation
  62. GRB 000301c: K' observations
  63. GRB 000301C Optical Observations
  64. GRB 000301C: K' Observations
  65. GRB000301C OT candidate optical observations
  66. GRB000301C - Host galaxy not detected in R (?)
  67. Optical observations of GRB000301c
  68. GRB000301C, Radio observations
  69. GRB000301C, Radio observations
  70. GRB000301C optical observations
  71. GRB000301C, near-infrared observations (JHK' imaging)
  72. GRB 000301c near-IR observations
  73. GRB 000301C, Optical Color
  74. GRB000301C, Optical Spectroscopy
  75. GRB 000301C, UBVRI field photometry
  76. GRB 000301C, Optical Observation
  77. GRB000301C, optical observations
  78. GRB000301C 250 GHz detection
  79. GRB 000301C R-band observation
  80. GRB 000301C, Optical Observation
  81. GRB000301C, near-infrared observations (JHK' photometry)
  82. GRB 000301C: OT confirmed
  83. GRB000301c optical observations
  84. GRB 000301A, Radio Observations
  85. GRB000301C, optical observations
  86. GRB000301c, near-infrared observations
  87. GRB000301C
  88. GRB 000301C : Optical Candidate
  89. Radio observations of the error box of GRB000301A
  90. GRB000301C: RXTE/ASM and IPN localizations
  91. GRB000226 [IPN Position]
  92. HST Observations of GRB 990712
  93. GRB 000214 near-IR observations
  94. GRB 000115 Optical observations
  95. GRB 000214, Radio Observations
  96. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  97. GRB000210, Radio Observations
  98. Correction to GCN 557 (GRB000214: BeppoSAX GRBM and WFC Detection)
  99. GRB 000115, BVRI field photometry
  100. GRB000214: BeppoSAX GRBM and WFC Detection

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