Skip to main content
New Announcement Feature, Code of Conduct, Circular Revisions. 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').

9654 results found.

  1. IPN/RXTE TRIANGULATION OF GRB010126
  2. GRB010126 optical observations
  3. IPN/RXTE TRIANGULATION OF GRB010126
  4. IPN TRIANGULATION OF GRB010115
  5. IPN triangulation of GRB001219
  6. GRB 001212 optical observation
  7. IPN triangulation of GRB001120
  8. GRB 001109 X-ray afterglow with BeppoSAX
  9. GRB001109: Optical observations
  10. GRB001109: BeppoSAX/NFI Observations
  11. XMM-Newton observation of GRB001025
  12. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  13. CORRECTION TO IPN/RXTE ERROR BOX FOR GRB001025
  14. ASM Localization of GRB 001025
  15. GRB001018, Gamma Ray Observations
  16. IPN TRIANGULATION OF GRB001019
  17. GRB 000926 Chandra Observation
  18. IPN triangulation of GRB 001004
  19. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  20. GRB000926 K'-band Observation
  21. IPN triangulation of GRB000925
  22. IPN triangulation of GRB000910
  23. IPN triangulation of GRB000830
  24. HST/STIS observations of the host galaxy of GRB 980329
  25. SGR 1806-20 burst activity
  26. GRB000801 & GRB000730, Gamma Ray Observations
  27. GRB000730, Gamma Ray Observations
  28. GRB000801, Gamma Ray Observations
  29. possible optical counterpart of GRB 000630
  30. IPN triangulation of GRB000630
  31. GRB 000623, optical observations
  32. GRB000620, optical observations
  33. GRB000620: BeppoSAX WFC and GRBM detection
  34. BeppoSAX ALERT: GRB000620
  35. GRB000620: BeppoSAX Alert
  36. GRB000616 [IPN Position]
  37. GRB000615B [IPN Position]
  38. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  39. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  40. GRB000519: Optical observations
  41. IPN triangulation of GRB000516
  42. GRB 000429, optical observation
  43. GRB 000418, UBVRI field photometry
  44. GRB 000418, Optical Observation
  45. GRB 000418, optical observation
  46. GRB 000418, Optical Observation
  47. GRB 000418, Optical Observation
  48. GRB000418, near-infrared observations
  49. IPN error box for GRB000418
  50. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  51. GRB 000408, optical observations
  52. GRB000313, Radio observations
  53. GRB000301C - B and R photometry
  54. GRB 000307, BVRI Field Photometry
  55. IPN error box for GRB000307
  56. GRB 000301C, UBVRI field photometry
  57. GRB 000301C, Optical Observation
  58. GRB 000301A, Radio Observations
  59. GRB 000301C : Optical Candidate
  60. GRB000226 [IPN Position]
  61. GRB 000115 Optical observations
  62. BATSE GRB trigger criterion changed
  63. GRB 000210: BATSE Observations
  64. GRB000210: BeppoSAX GRBM and WFC Detection
  65. GRB000201 Optical Observations
  66. BATSE Observations of GRB000115
  67. GCN resumes full operations
  68. Chandra observation of the X-ray afterglow of GRB991216
  69. GRB 991216 Optical spectroscopy/imaging
  70. GRB 991216 Optical Observation
  71. GRB 991216: Extremely bright BATSE burst
  72. IPN localization of GRB991208
  73. GRB 991105: BATSE Observations
  74. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  75. GRB 990915 optical observations
  76. BATSE GRB trigger criteria
  77. GRB990907: BeppoSAX follow up and X-ray afterglow
  78. GRB990806: BATSE Observations
  79. GRB 990705, R-band observations
  80. Infrared and Optical Observations of GRB990705
  81. GRB990704
  82. Refined BeppoSAX-WFC position of GRB990704
  83. GRB990704: BeppoSAX detection
  84. IPN error box for GRB990527
  85. Late Afterglows of GRBs 990510, 990123
  86. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  87. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  88. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  89. BeppoSAX: A new fast X-ray transient
  90. VLT spectrum of GRB990510
  91. GRB 990510: BATSE Observations
  92. GRB990510
  93. GRB 990506: BATSE Observations
  94. GRB 990506, optical observations
  95. GRB990506 Optical observations
  96. New IPN/RXTE error box for GRB990506
  97. GRB 970228: Redshift and properties of the host galaxy
  98. GRB980425 Optical observations of exponential decline at late time
  99. GRB990323 PRECISE IPN POSITION
  100. GRB990321 IPN TRIANGULATION

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