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"

28042 results found.

  1. GRB 000418, optical observation
  2. GRB 000418, Optical Observation
  3. GRB000418, near-infrared observations
  4. Correction to IPN error box for GRB000419
  5. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  6. GRB000416 BRJK observations
  7. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  8. GRB 000408, optical observations
  9. GRB 991208, UBVRI field photometry
  10. GRB000408, lotis optical observations
  11. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  12. GRB000301C - Addendum to GCN 623
  13. GRB 000323, optical observations
  14. GRB 000326: Optical Observations
  15. GRB000326, Radio observations
  16. GRB000313, Radio observations
  17. GRB 000313 - optical transient in the BATSE error box
  18. GRB 000307, Optical Observations
  19. GRB 000307, BVRI Field Photometry
  20. GRB 000301C: A Precise Redshift Determination
  21. GRB 000301C, Optical Observation
  22. GRB 000301C: HST/STIS CCD Imaging of the field
  23. IPN error box for GRB000307
  24. GRB000301C, optical R-band observations
  25. GRB 000301C Optical Observations
  26. GRB 000301C: K' Observations
  27. GRB000301C OT candidate optical observations
  28. GRB000301C - Host galaxy not detected in R (?)
  29. Optical observations of GRB000301c
  30. GRB000301C, Radio observations
  31. GRB000301C, Radio observations
  32. GRB000301C, near-infrared observations (JHK' imaging)
  33. GRB 000301c near-IR observations
  34. GRB 000301C, UBVRI field photometry
  35. GRB 000301C: OT confirmed
  36. GRB000301c optical observations
  37. GRB000301C, optical observations
  38. GRB000301C
  39. GRB 000301C : Optical Candidate
  40. GRB000301C: RXTE/ASM and IPN localizations
  41. GRB000226 [IPN Position]
  42. HST Observations of GRB 990712
  43. GRB 000214 near-IR observations
  44. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  45. GRB000210, Radio Observations
  46. GRB 000115, BVRI field photometry
  47. GRB000214: BeppoSAX GRBM and WFC Detection
  48. Optical observations of GRB000210
  49. GRB000210 X-ray afterglow
  50. GRB000214: X-ray afterglow candidate
  51. GRB000214 refined BeppoSAX-WFC position
  52. GRB 000210: BATSE Observations
  53. Optical observations of the Chandra X-ray source for GRB000210
  54. GRB000210, Radio Observations
  55. IPN triangulation of GRB000210
  56. GRB000210: possible afterglow detection with BeppoSAX NFI
  57. GRB000201, Radio Observations
  58. GRB000210: BeppoSAX GRBM and WFC Detection
  59. SAX_WFC_GRB_NOTICE
  60. SAX_WFC_GRB_NOTICE
  61. GRB000201 Optical Observations
  62. GRB 000201: TAROT optical observations
  63. GRB 991208, radio observations
  64. BATSE+IPN location of GRB000131
  65. IPN localization of GRB000131
  66. GRB 000126, optical observations
  67. BATSE Observations of GRB000115
  68. Second RXTE Observation of GRB 000115
  69. GRB991216, UBVRIJHK field photometry
  70. GCN resumes full operations
  71. GRB 991216 VLBA Observations
  72. GRB 991216: J band spectrophotometry
  73. GRB 991216: Detection of the Host and/or Absorber Galaxy
  74. IPN localization of GRB991226
  75. GRB 991216 RXTE ASM Observations
  76. GRB 991216: Updated BATSE parameters
  77. GRB 991217 (SAX J2303.2+0015) Optical observations
  78. Chandra observation of the X-ray afterglow of GRB991216
  79. GRB 991216, optical observations
  80. GRB 991216 Optical spectroscopy/imaging
  81. SAX J2303.2+0015 Optical observations
  82. IR observations of GRB991216
  83. GRB 991217 (SAX J2303.2+0015) Optical observations
  84. GRB991216 Optical and infrared observations of Beethoven Burst
  85. GRB 991216 Radio Observations
  86. GRB 991208 Keck Spectroscopy
  87. GRB 991208 Infrared Detection
  88. GRB991216
  89. GRB 991216--Summary of RXTE Observations
  90. GRB 991216 Optical Observations
  91. GRB 991216, optical observations
  92. GRB 991208 SAO-RAS Spectroscopy
  93. SAX J2303.2+0015: an x-ray/GRB?
  94. GRB 991216, Optical Transient
  95. GRB991216 ('Beethoven Burst') B, R, and K Observations
  96. GRB991216, infrared observations
  97. GRB 991208 optical observations
  98. GRB 991216 Optical Observation
  99. GRB 991216: Extremely bright BATSE burst
  100. R-band Observations of GRB991208 at TNG

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