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"

28049 results found.

  1. IPN triangulation of GRB050403 (small error box)
  2. GRB 030329: BVRI photometry at Asiago
  3. GRB 030329: VLT V-band photometry
  4. Kiso observation of the GRB030329 at April 6
  5. GRB 030329, color evolution
  6. GRB030328, UBVRcIc field photometry
  7. GRB 030329 Optical observations
  8. GRB030329: Kiso B and R band observations
  9. GRB030328: R upper limit after 6 hours by MASTER
  10. SDSS 0.5m PT observations of GRB030329 (correction)
  11. SDSS 0.5m PT observations of GRB030329
  12. GRB030329: final R-band light curve by MASTER
  13. GRB030329, optical observation
  14. GRB030329, new UBVRcIc field photometry
  15. GRB 030329, light curve and SN prediction
  16. GRB 030329, BRI photometry
  17. GRB030328: Full Observation, X-ray Fading and Spectrum Measured
  18. GRB030329: Optical observations at Teramo
  19. GRB 030329: Radio observations at GMRT
  20. Further AAVSO V,B,R observations of GRB030329
  21. GRB 030329: Additional Mt. Laguna Optical Observations
  22. GRB 030329: Observations with ANDICAM
  23. GRB030329: further optical photometry and evidence for a light curve discontinuity
  24. triangulation of GRB 030331 (single error box)
  25. GRB 030329: optical observations
  26. Photometry of GRB030329 - Constant OT Magnitude
  27. GRB030329 - OT brightens
  28. GRB 030329, optical photometry
  29. GRB 030324: Optical and NIR Observations
  30. GRB030329: R band light curve by MASTER
  31. GRB030329 - Light curve flattening
  32. GRB 030324, optical search
  33. GRB 030329, optical observations
  34. GRB030328: X-ray Fading and Spectrum Measured with Chandra
  35. GRB030329a: detection by Konus-Wind
  36. GRB030329b: detection by Konus-Wind and Helicon-CoronasF
  37. GRB030329, BVRcIc field photometry
  38. GRB030329, SPM optical observations
  39. GRB 030329: Optical decay and synthesis
  40. GRB030329 optical observations
  41. GRB 030329: Optical pre-Imaging
  42. GRB 030329: Upper limit from 5.6 hours before trigger
  43. GRB030328: X-ray Afterglow Observed with Chandra
  44. GRB 030329, R-band observations
  45. GRB 030329: OT B and R photometry, decline rate
  46. GRB030329: Upper limits from recent and historical observations.
  47. GRB030329 (=H2652): A Long, Extremely Bright GRB Localized by the HETE WXM and SXC
  48. GRB 030329: Optical Afterglow Observations
  49. GRB 030328: optical observations
  50. GRB 030329: Optical afterglow fading
  51. GRB 030328: OT photometry
  52. GRB030328: optical spectroscopy at TNG
  53. GRB030328: optical photometry at the TNG
  54. VLT spectra of GRB 030328
  55. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  56. GRB 030328: Optical observations
  57. GRB030324 optical observation
  58. GRB030131, BVRcIc field photometry
  59. Possible GRB030323 localized by INTEGRAL
  60. GRB030323: Detection on 2003/03/24
  61. IPN triangulation of GRB030326 (single small error box)
  62. IPN triangulation of GRB030325 (two small error boxes)
  63. GRB030323: V, R, I photometry
  64. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  65. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  66. VLT/FORS2 spectra of GRB 030323
  67. GRB030323, optical observations
  68. GRB030324, BVRcIc field photometry
  69. GRB030323, BVRcIc field calibration
  70. IPN triangulation of GRB030320 (small error box)
  71. Possible GRB 030320 localized by INTEGRAL
  72. IPN triangulation of GRB030306 (single small error box - REVISED)
  73. IPN triangulation of GRB030306 (single small error box)
  74. IPN triangulation of GRB030306 (two small error boxes)
  75. GRB030226, BVRc observations
  76. Chandra detection of the X-ray afterglow of GRB 030226
  77. GRB030227: Kiso optical upper limit
  78. GRB030227, BVRcIc field photometry
  79. GRB030226, BVRcIc field calibration
  80. GRB 030228, optical observations
  81. GRB 030227: Confirmed Optical Afterglow (S1-A)
  82. GRB 030227: fading of candidate optical afterglow 'S1-A'
  83. GRB030227:Optical observations
  84. GRB 030227, possible optical counterpart of XMM-Newton source
  85. GRB030227 - faint tentative OT candidate
  86. GRB 030226, optical observations
  87. XMM-Newton observation of GRB030227
  88. GRB030227: Kiso optical observations
  89. GRB 030227: Kyoto optical observation
  90. GRB 030226, optical light curve
  91. GRB030227 localized by INTEGRAL
  92. GRB 030226 : Predicted light curve
  93. GRB030226: ESI spectroscopy
  94. GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
  95. GRB 030226 simultaneous optical observations
  96. GRB 030226, optical observations
  97. GRB030226: Optical decay index
  98. GRB 030226 Optical Spectra and R,I,z' Imaging
  99. GRB: Non-Referencing of GCN Circulars.
  100. IPN triangulation of GRB030217 (small error box)

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