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"

37497 results found.

  1. GRB000326 [IPN Position]
  2. GRB 000307 optical observations
  3. GRB000323 [IPN Position]
  4. GRB000315 [IPN Positions]
  5. GRB 000313 - optical transient in the BATSE error box
  6. GRB000301C - B and R photometry
  7. GRB000301C - R photometry
  8. GRB 000307, Optical Observations
  9. GRB 000307, BVRI Field Photometry
  10. GRB 000301C: Optical Spectrum and Redshift
  11. GRB 000301C: Optical Spectrum and Redshift
  12. GRB 000301C: A Precise Redshift Determination
  13. GRB 000301C, Optical Observation
  14. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  15. GRB 000301C: HST/STIS CCD Imaging of the field
  16. IPN error box for GRB000307
  17. GRB 000301c: K' observations
  18. GRB000301C, optical R-band observations
  19. GRB000301c - R photometry and nearby faint source confirmation
  20. GRB 000301C, Optical Observation
  21. GRB 000301c: K' observations
  22. GRB 000301C Optical Observations
  23. GRB 000301C: K' Observations
  24. GRB000301C - Host galaxy not detected in R (?)
  25. GRB000301C optical observations
  26. GRB 000301c near-IR observations
  27. GRB 000301C, Optical Color
  28. GRB000301C, Optical Spectroscopy
  29. GRB 000301C, UBVRI field photometry
  30. GRB 000301C, Optical Observation
  31. GRB000301C 250 GHz detection
  32. GRB 000301C R-band observation
  33. GRB 000301C, Optical Observation
  34. GRB000301C, near-infrared observations (JHK' photometry)
  35. GRB 000301C: OT confirmed
  36. GRB000301c optical observations
  37. GRB 000301A, Radio Observations
  38. GRB000301C, optical observations
  39. GRB000301c, near-infrared observations
  40. GRB000301C
  41. GRB 000301C : Optical Candidate
  42. GRB000301C: RXTE/ASM and IPN localizations
  43. GRB000226 [IPN Position]
  44. HST Observations of GRB 990712
  45. GRB 000214 near-IR observations
  46. GRB 000115 Optical observations
  47. GRB 000214, Radio Observations
  48. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  49. GRB 000115, BVRI field photometry
  50. IPN annulus for GRB000214
  51. BATSE GRB trigger criterion changed
  52. GRB000210 X-ray afterglow
  53. GRB000214: X-ray afterglow candidate
  54. BeppoSAX GRB000214 ("S. Valentine's day GRB")
  55. GRB 000210: BATSE Observations
  56. Optical observations of the Chandra X-ray source for GRB000210
  57. Chandra Observations of GRB000210 X-ray Afterglow
  58. IPN triangulation of GRB000210
  59. GRB 000201: TAROT optical observations
  60. GRB 000131 Optical Observations
  61. GRB000126 Optical Observations
  62. BATSE GRB trigger criteria changed
  63. GRB 991208, radio observations
  64. BATSE+IPN location of GRB000131
  65. IPN localization of GRB000131
  66. GRB 000126, optical observations
  67. GRB000126, optical observations
  68. BATSE location of GRB000126
  69. IPN localization of GRB000126
  70. GRB 000115 Optical observations
  71. BATSE Observations of GRB000115
  72. Second RXTE Observation of GRB 000115
  73. GRB991216, UBVRIJHK field photometry
  74. Single IPN error box for GRB991229
  75. GRB 991216 VLBA Observations
  76. BEPPOSAX GRBM Localization of GRB991226
  77. IPN error boxes for GRB991229
  78. GRB 991216: J band spectrophotometry
  79. GRB 991216: Detection of the Host and/or Absorber Galaxy
  80. IPN localization of GRB991226
  81. Single IPN error box for GRB991221
  82. IPN error boxes for GRB991221
  83. GRB 991216 RXTE ASM Observations
  84. IPN error box for GRB991216
  85. GRB 991216: Updated BATSE parameters
  86. Lowell/Perkins observation of GRB 991216
  87. GRB 991217 (SAX J2303.2+0015) Optical observations
  88. Chandra observation of the X-ray afterglow of GRB991216
  89. GRB 991216, optical observations
  90. GRB 991216 Optical Observations
  91. GRB 991216 Optical spectroscopy/imaging
  92. K observations of GRB991216
  93. GRB 991217 (SAX J2303.2+0015) Optical observations
  94. GRB991216 Spectroscopy
  95. Lowell/Perkins observation of GRB 991216
  96. GRB991216, optical observations
  97. Refined IPN localization of GRB991216
  98. GRB 991216 Radio Observations
  99. GRB 991217
  100. GRB 991208 Keck Spectroscopy

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