Skip to main content
Circulars over Kafka event name backfill. 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').

32062 results found.

  1. Public availability of BeppoSAX data of GRB000926
  2. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  3. GRB 000926, Optical Decay
  4. GRB000911: VLT infrared observation
  5. GRB000926 - Optical observations
  6. GRB000926 - Optical observations
  7. GRB 000926: optical observations
  8. GRB 000926, Optical Observations
  9. GRB000911: optical VLT observations
  10. GRB000926 K'-band Observation
  11. GRB000926 : increasing optical decay slope
  12. GRB000926 optical observations
  13. GRB000926 - Optical observations
  14. Re: GRB 000926, optical observation by Oksanen (vsnet-grb)
  15. J and K band observations of GRB 000926
  16. GRB 000926: Lightcurve Update and Predictions
  17. GRB 000926, optical observation by Oksanen (vsnet-grb)
  18. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  19. CONCAM crude optical limits before and after GRB000926
  20. GRB 000926: Preliminary R-band Lightcurve
  21. GRB 000926 HST/Chandra TOO Status
  22. Spectroscopic Redshift of GRB 000926
  23. GRB 000926, Optical Observation
  24. GRB 000926: Optical candidate
  25. Optical candidate for GRB000926
  26. IPN triangulation of GRB000926
  27. GRB 000911, BVRI field photometry
  28. GRB000911: Sub-millimeter observations
  29. IPN triangulation of GRB000925
  30. IPN triangulation of GRB000911
  31. IPN triangulation of GRB000910
  32. False GRB alarm from RXTE/ASM on 8 Sept 2000
  33. GRB 000830: Optical observations
  34. GRB000830: Optical observations
  35. GRB000830, TNG B-band observations
  36. GRB000830, BVRI field photometry
  37. GRB000830: Optical observations
  38. GRB000210, Optical observations
  39. Chandra Position of GRB000210
  40. "Snapshot" afterglow IDs and GRB 000830
  41. IPN triangulation of GRB000830
  42. HST/STIS observations of the host galaxy of GRB 980329
  43. HST/STIS observations of the chaotic environment of GRB 980613
  44. IPN localization of GRB000820
  45. GRB000801 & GRB000730, Gamma Ray Observations
  46. GRB000730, Gamma Ray Observations
  47. GRB000812, Radio observations
  48. IPN localization of GRB000812
  49. IPN localization of GRB000811
  50. GRB000801, Gamma Ray Observations
  51. GRB000801, VLT-Antu R-band observations
  52. GRB 991208 Host Galaxy Imaging
  53. Updated IPN coordinates for GRB000801
  54. IPN localization of GRB000801
  55. IPN localization of GRB000730B
  56. IPN localization of GRB000730B
  57. IPN localization of GRB000730
  58. GRB 990510: Possible detection of a host galaxy
  59. GRB 990510 Host Galaxy Discovery
  60. GRB 000727, optical observations
  61. IPN localization of GRB000727
  62. GRB 990705, HST/STIS observations of the host galaxy
  63. GRB 990712: Late time HST/STIS Observations
  64. GRB 991216, HST/STIS observations
  65. GRB981226, HST/STIS observations of the host galaxy
  66. GRB 000630: Detection of the Optical Afterglow
  67. GRB000630, Revised BVRI Field Photometry
  68. GRB000630, Optical Observations
  69. GRB000630, optical observations
  70. GRB000630, BVRI Field Photometry
  71. GRB000630, optical observations
  72. GRB000630: Optical observations
  73. possible optical counterpart of GRB 000630
  74. IPN triangulation of GRB000630
  75. GRB 000623, optical observations
  76. GRB 000620, optical observations
  77. GRB000418, HST/STIS Observations
  78. GRB990123: Late-time HST/STIS observations of the host
  79. GRB 990506, HST/STIS Observations of the Host Galaxy
  80. GRB000623
  81. GRB 000620: J-band observations
  82. GRB990308, HST/STIS observations of the host galaxy
  83. IPN annulus for GRB000620
  84. GRB000615, Radio observations
  85. GRB000607, optical observations
  86. GRB 000615: NIR further observations
  87. BeppoSAX ALERT: GRB000620
  88. GRB000620: BeppoSAX Alert
  89. GRB990123, HST/STIS observations of the host galaxy
  90. GRB 000615, near-infrared observations
  91. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  92. GRB000616 [IPN Position]
  93. GRB000615B [IPN Position]
  94. GRB000615, further R-band photometry
  95. GRB 000615: NIR observations
  96. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  97. GRB000615, R-band photometry
  98. GRB980425, HST/STIS observations of the host galaxy
  99. GRB000615: BeppoSAX GRB Alert
  100. The Hosts of GRB 980703 and GRB 971214

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