Skip to main content
Circulars over Kafka event name backfill. 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"

24605 results found.

  1. IPN triangulation of GRB020910
  2. IPN GCN Circulars now to be issued without restriction
  3. Single IPN error box for GRB020904
  4. XRF 020903: optical observation at Kyoto
  5. GRB020322 : HST/STIS observations
  6. XRF 020903: Optical observations
  7. IPN triangulation of GRB020904
  8. INTEGRAL GRBs added to GCN
  9. SGR1900+14 burst localized by HETE
  10. GRB020813: High-resolution optical spectroscopy
  11. GRB020812: negative optical observations
  12. GRB 020812: optical observation at Kyoto University
  13. Second epoch K band imaging of GRB 020819
  14. GRB 020813 : HST observations
  15. GRB 020812: early time optical observation at Ouda Station
  16. GRB020813: Magellan BVRI Photometry
  17. GRB 020819: Optical observations
  18. K band observation of GRB 020819
  19. GRB020813: optical and NIR observations
  20. GRB020813: Fading X-ray Afterglow Observed with Chandra
  21. GRB020813, UBVRI field calibration
  22. GRB020812: NIR observations
  23. Polarimetry of GRB020813: evidence for variability
  24. GRB020813 IRAM millimeter observations
  25. GRB020812: optical observations
  26. GRB020813: High-Resolution Optical Observations
  27. GRB 020812: optical observation at Bisei
  28. GRB020813: Early Time Magnitude
  29. Millimeter observation of GRB 020813
  30. GRB020812: optical observations
  31. GRB 020813 : KISO multiband optical observations
  32. GRB020813, optical observations
  33. IPN error box for GRB020813
  34. GRB020813, astrometric position
  35. Spectropolarimetry of GRB 020813
  36. GRB 020812 optical observation
  37. GRB020812(=H2257): A Long Burst Localized by HETE in Near-Real Time
  38. GRB020801: Imaging of Suggested OT Counterpart at the Magellan
  39. HST Imaging of the Host of GRB 011121
  40. GRB020801, optical afterglow candidate
  41. GRB020331: Late-time Optical Light Curve (re-submission)
  42. GRB020331: Late-time Optical Light Curve
  43. IPN triangulation of GRB020714
  44. IPN triangulation of GRB020715 (=GRB150702)
  45. IPN triangulation of GRB020714
  46. IPN triangulation of GRB150702
  47. GRB 020410: Discovery of Probable OT by HST
  48. GRB 020124, HST observations of the fading afterglow
  49. IPN triangulation of GRB020708
  50. IPN triangulation of GRB020708
  51. Correction to IPN error box for GRB020706
  52. IPN triangulation of GRB020706
  53. GRB 020705: Optical observations
  54. GRB 020625, optical observations
  55. GRB 020625: Optical observations
  56. GRB 020531: optical photometry of Chandra sources
  57. GRB020625 (=H2081): A Long Burst Localized by HETE
  58. The Probable Host Galaxy of GRB/XRF 020427
  59. GRB/XRF 020427, detection of an underlying system with the VLT
  60. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  61. AXP 1E2259+586 optical observations
  62. Fading Optical Source in the Field of GRB020531
  63. GRB 020531, INT+WFC deep optical upper limits
  64. SGR-like Bursts from the AXP 1E 2259+586
  65. GRB020405: polarimetric observations
  66. GRB 020531, simultaneous optical observations
  67. GRB 020531/Candidate Redshift
  68. GRB020531: Detection of Candidate Host Galaxy
  69. GRB020531: Second epoch Chandra observations
  70. GRB020604, optical observations
  71. GRB020604, BVRcIc field photometry
  72. GRB020603, BVRcIc field observations
  73. GRB020531, BVRcIc field photometry
  74. GRB020531 Optical Observations
  75. GRB020531: Observations with the Chandra X-ray Observatory
  76. GRB020531, optical observations
  77. GRB020531: optical observations
  78. GRB020531(=H2042): Optical Observations
  79. GRB020531(=H2042): Optical Observations
  80. GRB020531: Optical observations
  81. GRB020531(=H2042): A Short, Hard Burst Localized by HETE
  82. GRB020525, optical observations
  83. HETE Observations of GX354-0 (= MXB1728-34, so-called "Slow
  84. XRF020427: Chandra Identification of a Likely X-ray Counterpart
  85. HST detection of the likely host galaxy of GRB 020124
  86. GRB020405 field photometry at ESO
  87. XRF020427: Chandra Observations and Candidate X-ray Counterparts
  88. GRB(XRF) 020427: X-ray afterglow with BeppoSAX
  89. GRB020321 : Optical observations.
  90. XRF 020427
  91. GRB 020124: Optical observations
  92. IPN triangulation of GRB020418
  93. GRB020405: VLT observations of the OT environment
  94. IPN triangulation of GRB020413
  95. GRB020405: predicted break
  96. GRB 020409: No Evidence for an Optical Afterglow
  97. GRB 020331 Kyoto observation on March 31
  98. GRB020410: BeppoSAX NFI observation
  99. X-ray afterglow of GRB020321
  100. GRB020331 optical observations with RIMOTS

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