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"

41682 results found.

  1. GRB981220
  2. GRB981220, Correction to GCN 179
  3. GRB981220, Optical Observations
  4. GRB 981220 Optical observations
  5. GRB 981226 Optical Observations
  6. GRB 980613: Spectroscopy of the host galaxy
  7. GRB981226, sub-millimeter observations
  8. GRB981220, sub-millimeter observations
  9. GRB 981220 and GRB 981226, optical observations
  10. GRB981226 Optical Observations
  11. GRB981226 BeppoSAX follow up
  12. GRB 981226 radio observations
  13. GRB 981226
  14. GRB 981226 optical observations
  15. radio observations of GRB 981226
  16. GRB981220 B, R and I band observations
  17. Optical Observations of GRB981226
  18. GRB 981220:Optical Observations
  19. GRB 981220 optical R and I observations
  20. GRB981226, BeppoSAX Christmas GRB
  21. GRB 981226 - Infrared Observations
  22. GRB 981226 optical observations
  23. GRB 981220
  24. GRB 981220, radio observations
  25. GRB981226 Optical Observation
  26. GRB 981220, radio observations
  27. GRB 981220: BeppoSAX/GRBM results
  28. GRB981220 I-band Observations
  29. GRB981220 Optical Observations
  30. GRB 981220
  31. GRB 981220 Optical Observations
  32. GRB 981220, optical observations
  33. GRB 980326/Host Galaxy
  34. GRB981220 IPN error box
  35. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  36. BeppoSAX NFI Observation of GRB980425
  37. GRB980329 R,I flux calibration and R,I,K upper limits
  38. GRB980425 Optical Follow-up
  39. GRB980425: X-ray revised positions
  40. GRB 980923 BATSE Observations
  41. SGR1900+14, BeppoSAX-GRBM observations
  42. GRB980703 Very Long Baseline Interferometry
  43. GRB970508 optical observations
  44. GRB971214, association with a Galactic star?
  45. Optical Observations of the Host Galaxy of GRB 980519
  46. GRB980519, Optical Observations
  47. GRB980703, Host galaxy multicolor photometry
  48. GRB980703 - BeppoSAX/GRBM detection
  49. GRB 980703 (NFI observations)
  50. GRB980703 optical photometry
  51. GRB 980703: BATSE Observations
  52. GRB980703 optical observations
  53. GRB980703: Radio transient
  54. GRB980703 H-band Observations
  55. GRB 980703: Spectrum of the proposed optical counterpart
  56. RXTE Observation of GRB 980706
  57. GRB980703: Spectrum of the proposed optical counterpart
  58. GRB980703 Transient Optical Follow-Up
  59. GRB980703: LOTIS observation at early times
  60. GRB980613 Optical Observations
  61. GRB 980703
  62. GRB980703 (I band observations)
  63. GRB 980703 H-band Observations
  64. GRB980703 (optical R observations)
  65. GRB980703: radio source/optical transient
  66. BeppoSAX NFI observations of GRB 980703
  67. GRB 980703: ASM Position & Intensity
  68. GRB980519 observation report
  69. GRB980703 optical followup
  70. Radio observations of SGRs
  71. SGR1900+14 field optical observations
  72. GRB 980613 Near-IR observations
  73. GRB980613, optical observations
  74. GRB 980613: Optical transient and its host galaxy
  75. SGR1627-41, RXTE/ASM observations
  76. SGR1627-41, Refined IPN annulus location
  77. GRB 980613: Detection of the probable host galaxy
  78. Reduced error box of SGR 1627-41
  79. GRB 980613: BATSE Observations
  80. SGR1627-41, BeppoSAX-GRBM detections
  81. GRB 980613 Optical Observations
  82. GRB 980613 optical observations
  83. Discovery of a new SGR source, SGR1627-41
  84. GRB980613 Optical Observations
  85. GRB980613 observations from Palomar
  86. GRB980613 BeppoSAX-NFI follow up
  87. GRB 980613 new optical/IR observations
  88. GRB 980613 optical/IR obs.
  89. GRB980613 Near Infra-Red Observations
  90. GRB971214 Secondary Standards
  91. SGR 1900+14
  92. GRB980519 Secondary Standards
  93. SGR1900+14
  94. SGR1900+14
  95. BATSE on-board GRB trigger change
  96. GRB 980519 Optical Observations
  97. GRB980519 optical observations
  98. GRB980519 I-band observations
  99. GRB 980519
  100. GRB980519 optical observations

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