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"

37520 results found.

  1. GRB010412: Optical observations
  2. GRB010412: Optical observations
  3. IPN Triangulation of GRB010412
  4. BeppoSAX GRB: extension of BSAX operations upto April 30, 2002
  5. BeppoSAX GRB ALERT: GRB010412
  6. GRB Observation Report
  7. GRB010324, revised field photometry
  8. REVISED LOCATION OF GRB010326A
  9. GRB 980326: Late-time HST/STIS observations
  10. GRB010324, field photometry
  11. GRB010326B, field photometry
  12. GRB010326, field photometry
  13. GRB010220, field photometry
  14. Further Optical Observations of GRB 010324
  15. GRB 010326A: Further optical observations
  16. GRB010324: BeppoSAX/GRBM data
  17. GRB 010326B: Optical observations
  18. GRB010324, optical observations
  19. GRB010326B: Localization by HETE (2nd GRB for this date)
  20. GRB 010326: Optical observations
  21. GRB 010326 optical observations
  22. GRB010326: Refined Localization by HETE
  23. GRB010326: Localization by HETE
  24. Duration, ECT, peak flux and fluence of GRB010324
  25. Optical Observations of GRB 010324
  26. IPN TRIANGULATION OF GRB010324
  27. GRB990705, VLT-FORS1 observations of the host galaxy
  28. GRB010222, late-time optical observation
  29. Support extension to the BeppoSAX mission
  30. GRB 010222 - HEGRA GeV/TeV Observations
  31. Congratulate Scott on the 1000th GRB Coordinates Network Circular!
  32. GRB010222: Chandra X-ray Observatory Observation
  33. GRB010222: Sub-millimeter vanishing act
  34. GRB 010222, Optical Observations
  35. GRB 010222: High-Resolution Keck Spectroscopy
  36. GRB 010214, I-band data
  37. Sub-millimeter Excess/GRB 010222
  38. GRB 010222
  39. GRB 010222 HST/Chandra TOO
  40. GRB 010222
  41. GRB010222 further R-band photometry
  42. GRB010222: R-band data
  43. GRB010222 Optical observations
  44. GRB 010222: Keck Spectroscopy
  45. GRB010214, field photometry
  46. GRB010222, field photometry
  47. GRB010222 further R-band photometry
  48. GRB010222, possible increase of optical decay slope
  49. GRB 010222 Kyoto optical observation
  50. GRB010222: fading behavior
  51. GRB 010222 BV optical observations
  52. GRB 010220: Near-IR Observations
  53. GRB010214 follow-up from Hanle
  54. GRB 010222: Near-IR Observations
  55. GRB 010222: Optical Observations
  56. GRB 010222, Decay Slope Confirmed
  57. GRB010222: Another absorption line system
  58. GRB010222: Optical decay slope
  59. GRB 010214, Optical Observations
  60. GRB010222: Sub-millimeter detection
  61. GRB010222: R-band fading behavior
  62. GRB010222: Optical Observations
  63. GRB010222, optical observations
  64. GRB010222: BeppoSAX/NFI Observations
  65. Redshift of the Optical Transient of GRB010222
  66. GRB010214B,Gamma Ray Observations
  67. GRB010222
  68. ALERT: GRB010222: the brightest GRB observed by BeppoSAX
  69. GRB 010220, simultaneous optical observations
  70. GRB010220: BeppoSAX WFC and GRBM preliminary data
  71. BeppoSAX ALERT: GRB010220
  72. GRB010214: BeppoSAX WFC and GRBM preliminary data
  73. GRB 010214: X-Ray afterglow
  74. GRB 010214, Optical Observations
  75. GRB 010214 optical observation
  76. GRB010213 Optical Observation
  77. J-Band Observation of GRB 010214.
  78. GRB010213, Near-IR observations
  79. Possible InfraRed Transient of GRB 010214.
  80. GRB010214 Optical Observation
  81. GRB010214: BeppoSAX/NFI Observations
  82. GRB010213 (HETE) TAROT observations
  83. GRB 010214, optical observations
  84. BeppoSAX ALERT: GRB010214
  85. IPN Status Report
  86. HETE Status
  87. GRB010126 opt. obs.
  88. IPN/RXTE TRIANGULATION OF GRB010126
  89. GRB010126: CONCAM crude optical limits during GRB
  90. GRB010126, TNG R-band observations
  91. IPN TRIANGULATION OF GRB010126
  92. IPN/RXTE TRIANGULATION OF GRB010126
  93. GRB 010119, optical observations
  94. GRB010119: Optical observations
  95. Optical Observations of GRB 001018 at Keck
  96. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  97. Optical observations of GRB 001018 with JCAM
  98. IPN TRIANGULATION OF GRB010115
  99. IPN TRIANGULATION OF GRB010109
  100. GRB010103, 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