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"

36786 results found.

  1. GRB 000623, optical observations
  2. GRB 000620, optical observations
  3. GRB000418, HST/STIS Observations
  4. GRB990123: Late-time HST/STIS observations of the host
  5. GRB 990506, HST/STIS Observations of the Host Galaxy
  6. GRB000623
  7. GRB 000620: J-band observations
  8. GRB990308, HST/STIS observations of the host galaxy
  9. IPN annulus for GRB000620
  10. GRB000615, Radio observations
  11. GRB000607, optical observations
  12. GRB 000615: NIR further observations
  13. BeppoSAX ALERT: GRB000620
  14. GRB000620: BeppoSAX Alert
  15. GRB990123, HST/STIS observations of the host galaxy
  16. GRB 000615, near-infrared observations
  17. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  18. GRB000616 [IPN Position]
  19. GRB000615B [IPN Position]
  20. GRB000615, further R-band photometry
  21. GRB 000615: NIR observations
  22. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  23. GRB000615, R-band photometry
  24. GRB980425, HST/STIS observations of the host galaxy
  25. GRB000615: BeppoSAX GRB Alert
  26. The Hosts of GRB 980703 and GRB 971214
  27. GRB 000301C: Further Late-Time HST/STIS observations
  28. GRB000528: follow-up X-ray measurements and update of IPN annulus
  29. GRB980519, HST/STIS observations of the host galaxy
  30. GRB000607, Radio Observations
  31. GRB000604 - Optical observations
  32. GRB000607, A SHORT, HARD BURST
  33. GRB000604, optical observations
  34. GRB000528, optical observations at ESO
  35. GRB 000604 optical observations
  36. GRB 000418: Detection of the Host Galaxy
  37. GRB000604, optical observations, comparison with DPOSS
  38. GRB000604 [IPN Position]
  39. X-ray Afterglow of GRB 000529
  40. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  41. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  42. IPN localization and time history of GRB000528
  43. New IPN localization of GRB000529
  44. GRB 000528 - WFC measurements
  45. GRB000528: BeppoSAX GRBM observations
  46. GRB 000528 Optical Observations
  47. GRB000519, BVRI field photometry
  48. IPN triangulation of GRB000519
  49. IPN triangulation of GRB000516
  50. Re: GRB000508B : Optical observations
  51. GRB 000418, Optical observation
  52. GRB000508B, optical photometry
  53. GRB000508B, BVR field photometry
  54. Possible GRB-related phenomenon
  55. RXTE/ASM and IPN localization of GRB 000508B
  56. GRB000424, UBVRI field photometry
  57. GRB 000424 Optical Observations
  58. GRB000418, UBVRI field photometry update
  59. The redshift of GRB 000418
  60. GRB 000429, optical observation
  61. GRB 000429, UBVRI field photometry
  62. IPN localization of GRB000429
  63. GRB 000418, UBVRI field photometry
  64. GRB000418, K'-band photometry
  65. GRB 000418, Optical Observation
  66. GRB 000418, optical observation
  67. GRB000424 Optical Observations
  68. GRB 000418, Optical Observation
  69. GRB 000424, Optical Observations
  70. GRB 000418, Optical Observation
  71. GRB000418, near-infrared observations
  72. Correction to IPN error box for GRB000419
  73. IPN error box for GRB000418
  74. GRB000419 [IPN Position]
  75. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  76. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  77. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  78. Budget cuts in BeppoSAX operations: impact on GRB observations
  79. GRB 000408, optical observations
  80. Refined IPN error box for GRB000408
  81. GRB 991208, UBVRI field photometry
  82. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  83. GRB000408 [IPN Position]
  84. GRB000326 Optical Observations
  85. GRB000301C - Addendum to GCN 623
  86. GRB000301C - R magnitude lower limit
  87. GRB 000323, optical observations
  88. GRB 000326: Optical Observations
  89. GRB000326, Radio observations
  90. GRB000326 [IPN Position]
  91. GRB 000307 optical observations
  92. GRB000323 [IPN Position]
  93. GRB000315 [IPN Positions]
  94. GRB 000313 - optical transient in the BATSE error box
  95. GRB000301C - B and R photometry
  96. GRB000301C - R photometry
  97. GRB 000307, Optical Observations
  98. GRB 000307, BVRI Field Photometry
  99. GRB 000301C: Optical Spectrum and Redshift
  100. GRB 000301C: Optical Spectrum and Redshift

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