Skip to main content
New! BOOM Notices and Schema v7.0.0. 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"

27395 results found.

  1. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  2. GRB 030328: Optical observations
  3. GRB030324 optical observation
  4. GRB030131, BVRcIc field photometry
  5. Possible GRB030323 localized by INTEGRAL
  6. GRB030323: Detection on 2003/03/24
  7. IPN triangulation of GRB030326 (single small error box)
  8. IPN triangulation of GRB030325 (two small error boxes)
  9. GRB030323: V, R, I photometry
  10. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  11. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  12. VLT/FORS2 spectra of GRB 030323
  13. GRB030323, optical observations
  14. GRB030324, BVRcIc field photometry
  15. GRB030323, BVRcIc field calibration
  16. IPN triangulation of GRB030320 (small error box)
  17. Possible GRB 030320 localized by INTEGRAL
  18. IPN triangulation of GRB030306 (single small error box - REVISED)
  19. IPN triangulation of GRB030306 (single small error box)
  20. IPN triangulation of GRB030306 (two small error boxes)
  21. GRB030226, BVRc observations
  22. Chandra detection of the X-ray afterglow of GRB 030226
  23. GRB030227: Kiso optical upper limit
  24. GRB030227, BVRcIc field photometry
  25. GRB030226, BVRcIc field calibration
  26. GRB 030228, optical observations
  27. GRB 030227: Confirmed Optical Afterglow (S1-A)
  28. GRB 030227: fading of candidate optical afterglow 'S1-A'
  29. GRB030227:Optical observations
  30. GRB 030227, possible optical counterpart of XMM-Newton source
  31. GRB030227 - faint tentative OT candidate
  32. GRB 030226, optical observations
  33. XMM-Newton observation of GRB030227
  34. GRB030227: Kiso optical observations
  35. GRB 030227: Kyoto optical observation
  36. GRB 030226, optical light curve
  37. GRB030227 localized by INTEGRAL
  38. GRB 030226 : Predicted light curve
  39. GRB030226: ESI spectroscopy
  40. GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
  41. GRB 030226 simultaneous optical observations
  42. GRB 030226, optical observations
  43. GRB030226: Optical decay index
  44. GRB 030226 Optical Spectra and R,I,z' Imaging
  45. GRB: Non-Referencing of GCN Circulars.
  46. IPN triangulation of GRB030217 (small error box)
  47. GRB 030131: marginal optical detection
  48. GRB 030204: Optical Observations
  49. GRB030204 field photometry
  50. GRB020819: Kiso R and I band observations
  51. GRB030131: Candidate Optical Afterglow
  52. IPN triangulation of GRB030204 (small error box)
  53. GRB 030131, optical observations
  54. GRB 030131: afterglow candidate
  55. GRB 030115, late-time optical observations
  56. GRB030131: corrected INTEGRAL position
  57. GRB 020819: Host galaxy at Radio Position
  58. IPN triangulation of GRB030131
  59. GRB 030131 optical observations
  60. GRB 030131 optical observations
  61. A long GRB detected by INTEGRAL
  62. GRB030115: 1.2 mm upper limits with MAMBO @ IRAM 30m
  63. GRB 030115, simultaneous observations by BOOTES-1
  64. GRB 030115: IR observations with IRSF/SIRIUS
  65. IPN triangulation of GRB030115C (large error box)
  66. GRB030115, afterglow candidate
  67. GRB 021211: R-band observations at late-time
  68. GRB030115: Optical Observations, Swiss Telescope at La Silla (ESO, Chile)
  69. GRB 030115 : Possible IR counterpart
  70. GRB030115 (=H2533): A Long GRB Localized by the HETE WXM and SXC
  71. Distribution of INTEGRAL SPI-ACS triggers for GRB bursts
  72. GRB 030115: APO Optical Observations
  73. Information about where HETE will be pointing
  74. VLT spectroscopy of the probable host of GRB 021211
  75. IPN triangulation of GRB030101 (two large error boxes)
  76. GRB 021211: Probable Host and Underlying Supernova
  77. GRB 021112: Evidence for Another Dark Optical Afterglow
  78. GRB 021219: OSN optical observations
  79. GRB021219, optical observations
  80. GRB021219, optical observation by MASTER
  81. VLT spectra of GRB 021211 revisited
  82. GRB021219: a long GRB localized by INTEGRAL
  83. GRB021211: APO optical observations
  84. XRF 020903 : HST observations
  85. GRB 021201: Optical Observations
  86. GRB 021211: CTIO observations
  87. GRB021211, BVRI field photometry
  88. GRB021211: Optical observations in CrAO
  89. GRB 021211, optical observations
  90. GRB021211: Kiso Observations
  91. GRB 021201, optical observations
  92. GRB021211: Optical observations
  93. GRB 021201 (short/hard), NOT observations
  94. SUB-MM SEARCH FOR GRB 021211
  95. Chandra observation of the IPN error box of GRB021201 (short/hard)
  96. GRB 021211, R- and I-band observations
  97. GRB021211 - Upper limits from recent and historical observations
  98. GRB021211 (=H2493): A Bright, Long GRB Localized by HETE-2 in Near-Real Time
  99. IPN triangulation of GRB021206 (small error box)
  100. IPN triangulation of GRB021205 (large error box)

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