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"

28056 results found.

  1. GRB 990316 optical observations
  2. GRB990316: simultaneous optical observation
  3. GRB990316 - Optical null results
  4. GRB990308 not a new SGR
  5. GRB 990308a and GRB 990308b
  6. GRB990308, Possible new SGR~0209+70
  7. GRB 990123, Field Photometry
  8. GRB 990217 Optical Observations
  9. BATSE Flight Anomaly
  10. GRB990217: BeppoSAX/GRBM data
  11. GRB990123 observations
  12. GRB990217 Optical observation
  13. GRB990123, Optical Observation
  14. GRB 990123: Discovery of the Probable Host Galaxy
  15. GRB 990123: Reduced HST Images
  16. GRB19990123 observations
  17. GRB 990123: BVRI standards in the field
  18. GRB981220, field photometry
  19. GRB990123, Optical observation
  20. GRB990123, 15-GHz limits
  21. GRB 990123: New Constraints on Possible Foreground Galaxies
  22. GRB990123 Optical Observations
  23. GRB990123, Probability of gravitational lensing
  24. GRB 990123: Detection of the IR Transient, and the Light Curve Fits
  25. GRB990123, Preliminary Lens Search Results
  26. On the Lensing Interpretation of GRB 990123
  27. Search for Potential Images of GRB 990123
  28. Search for Potential Images of GRB 990123
  29. GRB990123, Optical BVRI Observations
  30. GRB 990123: near-infrared observations.
  31. GRB990123, OSSE observations
  32. GRB990123: NIR Observation
  33. GRB990123, ASCA X-ray observation of afterglow
  34. "GRB 990123: New BV Observations"
  35. GRB 990123 Optical Follow-Up
  36. GRB 990123: BATSE Observations
  37. GRB990123 Optical Observations
  38. GRB 990123: New Optical Observations, Decay Measure
  39. GRB 990123 Optical Follow-Up
  40. GRB 990123: Possible Gravitationally Lensed Burst?
  41. GRB990123, optical observation
  42. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  43. GRB990123, Optical observation
  44. GRB 990123: Optical Decay Slope
  45. GRB 990123 r-band photometry
  46. GRB 990123 Optical Follow-up
  47. GRB990123, early optical counterpart detection
  48. GRB990123 Optical Observation
  49. Possible identification of SN1999E with GRB980910
  50. Optical Observations of GRB 981220
  51. GRB 981226: radio variable
  52. GRB981220
  53. GRB981220, Correction to GCN 179
  54. GRB 981220 Optical observations
  55. GRB 981226 Optical Observations
  56. GRB 981220 and GRB 981226, optical observations
  57. GRB981226 Optical Observations
  58. GRB981226 BeppoSAX follow up
  59. GRB 981226
  60. GRB 981226 optical observations
  61. GRB981220 B, R and I band observations
  62. Optical Observations of GRB981226
  63. GRB 981220:Optical Observations
  64. GRB 981226 optical observations
  65. GRB 981220
  66. GRB 981220, radio observations
  67. GRB981220 I-band Observations
  68. GRB 981220
  69. GRB 980326/Host Galaxy
  70. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  71. BeppoSAX NFI Observation of GRB980425
  72. GRB980329 R,I flux calibration and R,I,K upper limits
  73. GRB980425 Optical Follow-up
  74. GRB 980923 BATSE Observations
  75. SGR1900+14, BeppoSAX-GRBM observations
  76. GRB970508 optical observations
  77. GRB971214, association with a Galactic star?
  78. GRB980519, Optical Observations
  79. GRB980703 - BeppoSAX/GRBM detection
  80. GRB980703 optical photometry
  81. GRB 980703: BATSE Observations
  82. GRB980703 optical observations
  83. GRB980703: Radio transient
  84. GRB 980703: Spectrum of the proposed optical counterpart
  85. GRB980703 Transient Optical Follow-Up
  86. GRB980703: LOTIS observation at early times
  87. GRB980613 Optical Observations
  88. GRB980703 (I band observations)
  89. BeppoSAX NFI observations of GRB 980703
  90. GRB980519 observation report
  91. GRB980703 optical followup
  92. Radio observations of SGRs
  93. SGR1900+14 field optical observations
  94. GRB980613, optical observations
  95. GRB 980613: Optical transient and its host galaxy
  96. SGR1627-41, RXTE/ASM observations
  97. GRB 980613: Detection of the probable host galaxy
  98. Reduced error box of SGR 1627-41
  99. GRB 980613: BATSE Observations
  100. GRB 980613 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