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"

24366 results found.

  1. GRB000926 - Optical observations
  2. GRB000911: VLT infrared observation
  3. GRB000911: optical VLT observations
  4. GRB000926 K'-band Observation
  5. J and K band observations of GRB 000926
  6. IPN triangulation of GRB000911
  7. False GRB alarm from RXTE/ASM on 8 Sept 2000
  8. GRB000830: Optical observations
  9. GRB000830, TNG B-band observations
  10. IPN localization of GRB000820
  11. GRB000812, TNG R-band observations
  12. GRB000730, Gamma Ray Observations
  13. IPN localization of GRB000812
  14. IPN localization of GRB000811
  15. GRB000801, Gamma Ray Observations
  16. IPN localization of GRB000801
  17. IPN localization of GRB000801
  18. IPN localization of GRB000730B
  19. IPN localization of GRB000730B
  20. IPN localization of GRB000730
  21. GRB 990510: Possible detection of a host galaxy
  22. GRB 990510 Host Galaxy Discovery
  23. IPN localization of GRB000727
  24. GRB 990712: Late time HST/STIS Observations
  25. GRB 991216, HST/STIS observations
  26. GRB 000630: Detection of the Optical Afterglow
  27. GRB000630, Optical Observations
  28. GRB000630, optical observations
  29. GRB000418, HST/STIS Observations
  30. GRB990123: Late-time HST/STIS observations of the host
  31. GRB 990506, HST/STIS Observations of the Host Galaxy
  32. GRB000623
  33. GRB 000620: J-band observations
  34. GRB000620, optical observations
  35. GRB000607, optical observations
  36. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  37. GRB000616 [IPN Position]
  38. GRB 000615: NIR observations
  39. GRB980425, HST/STIS observations of the host galaxy
  40. The Hosts of GRB 980703 and GRB 971214
  41. GRB 000301C: Further Late-Time HST/STIS observations
  42. GRB000528: follow-up X-ray measurements and update of IPN annulus
  43. GRB000607, Radio Observations
  44. GRB000607, A SHORT, HARD BURST
  45. IPN localization and time history of GRB000528
  46. New IPN localization of GRB000529
  47. IPN localization of GRB000529
  48. GRB000528: BeppoSAX GRBM observations
  49. Possible GRB-related phenomenon
  50. RXTE/ASM and IPN localization of GRB 000508B
  51. GRB 000424 Optical Observations
  52. IPN localization of GRB000429
  53. GRB 000418, optical observation
  54. GRB000424 Optical Observations
  55. GRB000424, optical observations
  56. GRB 000424, Optical Observations
  57. Correction to IPN error box for GRB000419
  58. GRB000416 Optical Observations
  59. GRB000416 BRJK observations
  60. GRB000301c results
  61. GRB000408, lotis optical observations
  62. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  63. GRB000408 [IPN Position]
  64. GRB000301C - R magnitude lower limit
  65. GRB 000313 - optical transient in the BATSE error box
  66. GRB 000301C: Optical Spectrum and Redshift
  67. GRB 000301C: Optical Spectrum and Redshift
  68. GRB 000301C: HST/STIS CCD Imaging of the field
  69. GRB 000301C, Optical Observation
  70. GRB 000301c: K' observations
  71. GRB 000301C: K' Observations
  72. GRB000301C - Host galaxy not detected in R (?)
  73. GRB000301C, near-infrared observations (JHK' imaging)
  74. GRB 000301c near-IR observations
  75. GRB 000301C, Optical Color
  76. GRB000301C 250 GHz detection
  77. GRB000301C, optical observations
  78. GRB000301C
  79. GRB000301C: RXTE/ASM and IPN localizations
  80. GRB000301A [IPN Position]
  81. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  82. GRB000210 X-ray afterglow
  83. BeppoSAX GRB000214 ("S. Valentine's day GRB")
  84. GRB 000210: BATSE Observations
  85. Optical candidate for GRB000210
  86. SAX_WFC_GRB_NOTICE
  87. SAX_WFC_GRB_NOTICE
  88. GRB000201 Optical Observations
  89. BATSE+IPN location of GRB000131
  90. IPN localization of GRB000131
  91. GRB 000126, optical observations
  92. BATSE location of GRB000126
  93. IPN localization of GRB000126
  94. BATSE Observations of GRB000115
  95. Second RXTE Observation of GRB 000115
  96. GRB991216 late optical observation
  97. Single IPN error box for GRB991229
  98. GCN resumes full operations
  99. BEPPOSAX GRBM Localization of GRB991226
  100. GRB 991216: J band spectrophotometry

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