Skip to main content
New! Browse Circulars by Event, Advanced Search, Sample Codes, Schema Release. 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"

25087 results found.

  1. GRB020813: optical and NIR observations
  2. GRB020813: Fading X-ray Afterglow Observed with Chandra
  3. GRB020813, UBVRI field calibration
  4. GRB020812: NIR observations
  5. Polarimetry of GRB020813: evidence for variability
  6. GRB020813 IRAM millimeter observations
  7. GRB020812: optical observations
  8. GRB020813: High-Resolution Optical Observations
  9. GRB 020812: optical observation at Bisei
  10. GRB020813: Early Time Magnitude
  11. Millimeter observation of GRB 020813
  12. GRB020812: optical observations
  13. GRB 020813 : KISO multiband optical observations
  14. GRB020813, optical observations
  15. IPN error box for GRB020813
  16. GRB020813, astrometric position
  17. Spectropolarimetry of GRB 020813
  18. GRB 020812 optical observation
  19. GRB020812(=H2257): A Long Burst Localized by HETE in Near-Real Time
  20. GRB020801: Imaging of Suggested OT Counterpart at the Magellan
  21. HST Imaging of the Host of GRB 011121
  22. GRB020801, optical afterglow candidate
  23. GRB020331: Late-time Optical Light Curve (re-submission)
  24. GRB020331: Late-time Optical Light Curve
  25. IPN triangulation of GRB020714
  26. IPN triangulation of GRB020715 (=GRB150702)
  27. IPN triangulation of GRB020714
  28. IPN triangulation of GRB150702
  29. GRB 020410: Discovery of Probable OT by HST
  30. GRB 020124, HST observations of the fading afterglow
  31. IPN triangulation of GRB020708
  32. IPN triangulation of GRB020708
  33. Correction to IPN error box for GRB020706
  34. IPN triangulation of GRB020706
  35. GRB 020705: Optical observations
  36. GRB 020625, optical observations
  37. GRB 020625: Optical observations
  38. GRB 020531: optical photometry of Chandra sources
  39. GRB020625 (=H2081): A Long Burst Localized by HETE
  40. The Probable Host Galaxy of GRB/XRF 020427
  41. GRB/XRF 020427, detection of an underlying system with the VLT
  42. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  43. AXP 1E2259+586 optical observations
  44. Fading Optical Source in the Field of GRB020531
  45. GRB 020531, INT+WFC deep optical upper limits
  46. SGR-like Bursts from the AXP 1E 2259+586
  47. GRB020405: polarimetric observations
  48. GRB 020531, simultaneous optical observations
  49. GRB 020531/Candidate Redshift
  50. GRB020531: Detection of Candidate Host Galaxy
  51. GRB020531: Second epoch Chandra observations
  52. GRB020604, optical observations
  53. GRB020604, BVRcIc field photometry
  54. GRB020603, BVRcIc field observations
  55. GRB020531, BVRcIc field photometry
  56. GRB020531 Optical Observations
  57. GRB020531: Observations with the Chandra X-ray Observatory
  58. GRB020531, optical observations
  59. GRB020531: optical observations
  60. GRB020531(=H2042): Optical Observations
  61. GRB020531(=H2042): Optical Observations
  62. GRB020531: Optical observations
  63. GRB020531(=H2042): A Short, Hard Burst Localized by HETE
  64. GRB020525, optical observations
  65. HETE Observations of GX354-0 (= MXB1728-34, so-called "Slow
  66. XRF020427: Chandra Identification of a Likely X-ray Counterpart
  67. HST detection of the likely host galaxy of GRB 020124
  68. GRB020405 field photometry at ESO
  69. XRF020427: Chandra Observations and Candidate X-ray Counterparts
  70. GRB(XRF) 020427: X-ray afterglow with BeppoSAX
  71. GRB020321 : Optical observations.
  72. XRF 020427
  73. GRB 020124: Optical observations
  74. IPN triangulation of GRB020418
  75. GRB020405: VLT observations of the OT environment
  76. IPN triangulation of GRB020413
  77. GRB020405: predicted break
  78. GRB 020409: No Evidence for an Optical Afterglow
  79. GRB 020331 Kyoto observation on March 31
  80. GRB020410: BeppoSAX NFI observation
  81. X-ray afterglow of GRB020321
  82. GRB020331 optical observations with RIMOTS
  83. GRB020124 optical observations with RIBOTS/RIMOTS
  84. GRB 020321: Candidate X-ray Counterparts
  85. GRB020406(?), optical observations
  86. GRB 020405: Decay index
  87. Short RXTE/ASM transient 020406; may be a GRB
  88. GRB020405, Radio Observations
  89. GRB 020405, U-band observations
  90. GRB011212: Optical Observations
  91. GRB 020331: NIR Observations
  92. GRB020331 NIR observation at KPNO (re-submission)
  93. GRB02033 NIR observation at KPNO
  94. GRB020331 field photometry
  95. GRB 020331, NIR observations
  96. GRB020331(=H1963): The "Easter" Burst Detected by HETE
  97. GRB 020322: BeppoSAX observations of the X-ray afterglow
  98. GRB011211: HST Observations of Optical Afterglow and Host Galaxy
  99. Near-Infrared Observations of GRB020322 at TIRGO
  100. GRB 020321, Radio Observations

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