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"

36132 results found.

  1. The redshift of GRB 000418
  2. GRB 000429, optical observation
  3. GRB 000429, UBVRI field photometry
  4. IPN localization of GRB000429
  5. GRB 000418, UBVRI field photometry
  6. GRB000418, K'-band photometry
  7. GRB 000418, Optical Observation
  8. GRB 000418, optical observation
  9. GRB000424 Optical Observations
  10. GRB 000418, Optical Observation
  11. GRB 000424, Optical Observations
  12. GRB 000418, Optical Observation
  13. GRB000418, near-infrared observations
  14. Correction to IPN error box for GRB000419
  15. IPN error box for GRB000418
  16. GRB000419 [IPN Position]
  17. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  18. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  19. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  20. Budget cuts in BeppoSAX operations: impact on GRB observations
  21. GRB 000408, optical observations
  22. Refined IPN error box for GRB000408
  23. GRB 991208, UBVRI field photometry
  24. GRB000301c results
  25. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  26. GRB000408 [IPN Position]
  27. GRB000326 Optical Observations
  28. GRB000301C - Addendum to GCN 623
  29. GRB000301C - R magnitude lower limit
  30. GRB 000323, optical observations
  31. GRB 000326: Optical Observations
  32. GRB000326, Radio observations
  33. GRB000326 [IPN Position]
  34. GRB 000307 optical observations
  35. GRB000323 [IPN Position]
  36. GRB000315 [IPN Positions]
  37. GRB 000313 - optical transient in the BATSE error box
  38. GRB000301C - B and R photometry
  39. GRB000301C - R photometry
  40. GRB 000307, Optical Observations
  41. GRB 000307, BVRI Field Photometry
  42. GRB 000301C: Optical Spectrum and Redshift
  43. GRB 000301C: Optical Spectrum and Redshift
  44. GRB 000301C: A Precise Redshift Determination
  45. GRB 000301C, Optical Observation
  46. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  47. GRB 000301C: HST/STIS CCD Imaging of the field
  48. IPN error box for GRB000307
  49. GRB 000301c: K' observations
  50. GRB000301C, optical R-band observations
  51. GRB000301c - R photometry and nearby faint source confirmation
  52. GRB 000301C, Optical Observation
  53. GRB 000301c: K' observations
  54. GRB 000301C Optical Observations
  55. GRB 000301C: K' Observations
  56. GRB000301C - Host galaxy not detected in R (?)
  57. Optical observations of GRB000301c
  58. GRB000301C optical observations
  59. GRB 000301c near-IR observations
  60. GRB 000301C, Optical Color
  61. GRB000301C, Optical Spectroscopy
  62. GRB 000301C, UBVRI field photometry
  63. GRB 000301C, Optical Observation
  64. GRB000301C 250 GHz detection
  65. GRB 000301C R-band observation
  66. GRB 000301C, Optical Observation
  67. GRB000301C, near-infrared observations (JHK' photometry)
  68. GRB 000301C: OT confirmed
  69. GRB000301c optical observations
  70. GRB 000301A, Radio Observations
  71. GRB000301C, optical observations
  72. GRB000301c, near-infrared observations
  73. GRB000301C
  74. GRB 000301C : Optical Candidate
  75. GRB000301C: RXTE/ASM and IPN localizations
  76. GRB000226 [IPN Position]
  77. HST Observations of GRB 990712
  78. GRB 000214 near-IR observations
  79. GRB 000115 Optical observations
  80. GRB 000214, Radio Observations
  81. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  82. GRB 000115, BVRI field photometry
  83. IPN annulus for GRB000214
  84. BATSE GRB trigger criterion changed
  85. GRB000210 X-ray afterglow
  86. GRB000214: X-ray afterglow candidate
  87. BeppoSAX GRB000214 ("S. Valentine's day GRB")
  88. GRB 000210: BATSE Observations
  89. Optical observations of the Chandra X-ray source for GRB000210
  90. Chandra Observations of GRB000210 X-ray Afterglow
  91. IPN triangulation of GRB000210
  92. GRB 000201: TAROT optical observations
  93. GRB 000131 Optical Observations
  94. GRB000126 Optical Observations
  95. BATSE GRB trigger criteria changed
  96. GRB 991208, radio observations
  97. BATSE+IPN location of GRB000131
  98. IPN localization of GRB000131
  99. GRB 000126, optical observations
  100. GRB000126, 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