Skip to main content
New! BOOM Notices and Schema v7.0.0. 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"

35422 results found.

  1. GRB 000424, Optical Observations
  2. GRB 000418, Optical Observation
  3. GRB000418, near-infrared observations
  4. Correction to IPN error box for GRB000419
  5. IPN error box for GRB000418
  6. GRB000419 [IPN Position]
  7. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  8. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  9. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  10. Budget cuts in BeppoSAX operations: impact on GRB observations
  11. GRB 000408, optical observations
  12. Refined IPN error box for GRB000408
  13. GRB 991208, UBVRI field photometry
  14. GRB000301c results
  15. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  16. GRB000408 [IPN Position]
  17. GRB000326 Optical Observations
  18. GRB000301C - Addendum to GCN 623
  19. GRB000301C - R magnitude lower limit
  20. GRB 000323, optical observations
  21. GRB 000326: Optical Observations
  22. GRB000326, Radio observations
  23. GRB000326 [IPN Position]
  24. GRB 000307 optical observations
  25. GRB000323 [IPN Position]
  26. GRB000315 [IPN Positions]
  27. GRB 000313 - optical transient in the BATSE error box
  28. GRB000301C - B and R photometry
  29. GRB000301C - R photometry
  30. GRB 000307, Optical Observations
  31. GRB 000307, BVRI Field Photometry
  32. GRB 000301C: Optical Spectrum and Redshift
  33. GRB 000301C: Optical Spectrum and Redshift
  34. GRB 000301C: A Precise Redshift Determination
  35. GRB 000301C, Optical Observation
  36. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  37. GRB 000301C: HST/STIS CCD Imaging of the field
  38. IPN error box for GRB000307
  39. GRB 000301c: K' observations
  40. GRB000301C, optical R-band observations
  41. GRB000301c - R photometry and nearby faint source confirmation
  42. GRB 000301C, Optical Observation
  43. GRB 000301c: K' observations
  44. GRB 000301C Optical Observations
  45. GRB 000301C: K' Observations
  46. GRB000301C - Host galaxy not detected in R (?)
  47. Optical observations of GRB000301c
  48. GRB000301C optical observations
  49. GRB 000301c near-IR observations
  50. GRB 000301C, Optical Color
  51. GRB000301C, Optical Spectroscopy
  52. GRB 000301C, UBVRI field photometry
  53. GRB 000301C, Optical Observation
  54. GRB000301C 250 GHz detection
  55. GRB 000301C R-band observation
  56. GRB 000301C, Optical Observation
  57. GRB000301C, near-infrared observations (JHK' photometry)
  58. GRB 000301C: OT confirmed
  59. GRB000301c optical observations
  60. GRB 000301A, Radio Observations
  61. GRB000301C, optical observations
  62. GRB000301c, near-infrared observations
  63. GRB000301C
  64. GRB 000301C : Optical Candidate
  65. GRB000301C: RXTE/ASM and IPN localizations
  66. GRB000226 [IPN Position]
  67. HST Observations of GRB 990712
  68. GRB 000214 near-IR observations
  69. GRB 000115 Optical observations
  70. GRB 000214, Radio Observations
  71. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  72. GRB 000115, BVRI field photometry
  73. IPN annulus for GRB000214
  74. BATSE GRB trigger criterion changed
  75. GRB000210 X-ray afterglow
  76. GRB000214: X-ray afterglow candidate
  77. BeppoSAX GRB000214 ("S. Valentine's day GRB")
  78. GRB 000210: BATSE Observations
  79. Optical observations of the Chandra X-ray source for GRB000210
  80. Chandra Observations of GRB000210 X-ray Afterglow
  81. IPN triangulation of GRB000210
  82. GRB 000201: TAROT optical observations
  83. GRB 000131 Optical Observations
  84. GRB000126 Optical Observations
  85. BATSE GRB trigger criteria changed
  86. GRB 991208, radio observations
  87. BATSE+IPN location of GRB000131
  88. IPN localization of GRB000131
  89. GRB 000126, optical observations
  90. GRB000126, optical observations
  91. BATSE location of GRB000126
  92. IPN localization of GRB000126
  93. GRB 000115 Optical observations
  94. BATSE Observations of GRB000115
  95. Second RXTE Observation of GRB 000115
  96. GRB991216, UBVRIJHK field photometry
  97. Single IPN error box for GRB991229
  98. GCN resumes full operations
  99. GRB 991216 VLBA Observations
  100. BEPPOSAX GRBM Localization of GRB991226

Advanced

Download all Circulars as a .tar.gz archive:
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