Skip to main content
JSON Notices via Email, Kafka Cron Jobs, Submitter Profile, GCN is Hiring. See news and announcements

GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"
  1. Increase of SGR 1806-20 activity
  2. GRB040825A: optical observations
  3. GRB040825B: optical observations
  4. GRB040825B (=H3510): An XRF Localized in Real Time by HETE
  5. GRB 040825A: Optical observations.
  6. MASTER: GRB040825a optical observation
  7. MASTER: GRB040825b optical observation
  8. GRB040825B: Correction to GCN 2657
  9. GRB 040825: Optical observations
  10. XRF040812: possible afterglow second Chandra observation
  11. GRB 040812: Second epoch CXO Observations
  12. GRB040823,optical observation
  13. XRF040812: GMRT observations
  14. Triangulation of GRB 040816 (Konus-Wind - Helicon-Coronas-F)
  15. XRF 040812: optical observation at VLT
  16. GRB 040812: Optical counterparts of CXO sources
  17. XRF040812: possible afterglow
  18. CXO observation of GRB 040812
  19. Bursting activity from SGR 1806-20 detected with IBAS
  20. IPN/HETE localizations of GRB040810 (=H3489)
  21. GRB 040812: Keck and LCO optical observations
  22. GRB 040812: Keck and LCO observations
  23. GRB 040812: radio observations
  24. GRB040812, optical/IR observations
  25. Konus-Wind observation of GRB040810 (=H3489)
  26. GRB 040812: a long GRB detected by INTEGRAL
  27. GRB 040810: Optical observations of a limited region
  28. XRF040701: Optical Observations at ESO
  29. IPN/HETE triangulation of GRB040802 (=H3485)
  30. GRB 040730, infrared observations
  31. GRB 040730: Optical observations
  32. GRB 040730: a long GRB detected with INTEGRAL
  33. Ongoing activity of SGR 1806-20
  34. GRB040624: optical monitoring at TNG
  35. XRF 040701 - optical observations of the decaying Chandra source
  36. XRF040701: Second-Epoch Chandra Observations
  37. Cancellation of IBAS/INTEGRAL GRB alerts
  38. XRF040701: VLA Observations
  39. XRF040701: Magellan Spectroscopy of Chandra Source #2 Associated Galaxy
  40. XRF040701: First-Epoch Chandra Observations
  41. IBAS Alert 1836: NOT a real GRB
  42. GRB040709 J,H-band observations
  43. GRB040624, optical observations
  44. GRB040706:observation at University of Miyazaki
  45. XRF 040701, optical observations
  46. XRF040701 (=U11548): a bright XRF detected by HETE
  47. GRB 040624: optical observations
  48. Optical Observations of GRB040624
  49. GRB 040624: optical observations at TNG and VLT
  50. MASTER: GRB 040624 optical observation after 0,48d
  51. GRB 040624: R-band observations
  52. GRB 040624, optical observations
  53. GRB 040624 - A long GRB detected with INTEGRAL
  54. GRB 030329: Rebrightening of hyperluminal ejecta.
  55. IPN Summary of SGR1806-20 Activity in 2004
  56. GRB040511: Retraction of redshift identification
  57. SGR 1806-20: no IR variability of the proposed counterparts
  58. MASTER:HETE Alert 3259 (SRG1806-20) optical observation
  59. SGR 1806-20, potential NIR counterpart
  60. GRB 040606: Optical observations
  61. MASTER: HETE Alert 3274 optical observation
  62. Activivty of SGR 1806-20
  63. IPN triangulation of an intense intermediate burst from SGR1806-20
  64. GRB 040511, very fast decay?
  65. GRB 030324: Detection and Color of Host Galaxy
  66. GRB 040511: NIR observations with REM
  67. GRB040511: Redshift identifcation
  68. GRB 040511: Optical limit
  69. GRB040511: Candidate optical/NIR afterglow
  70. IBAS GRB Alerts n.1785 to 1791
  71. GRB 040511: ROTSE-III Rapid Optical Upper Limits
  72. GRB 040511: Second Epoch Optical Observations
  73. IBAS GRB Alerts 1781-4
  74. GRB 040511: Optical observations
  75. GRB 040511: Optical Observations
  76. GRB040511: Optical Observations
  77. GRB040511: Optical Observations
  78. GRB040511 (=H3218): A Long GRB Localized by HETE WXM and SXC
  79. IBAS GRB Alert number 1774: NOT a real GRB
  80. Type Ic SN2001em (off-axis GRB jet?), optical spectrum
  81. IBAS Alerts 1771 and 1772: NOT a real GRB
  82. GRB and XRF on April 27, 2004. Detection by Konus-Wind and Helicon (Coronas-F)
  83. IPN triangulation of GRB040425 (=H3183)
  84. On Line Availability of Archival HETE Fregate Data and Lightcurves
  85. GRB040422: optical observations at Xinglong Observatory
  86. GRB040422: optical observations at CrAO
  87. GRB 040423 (=H3175): A Long GRB Localized by HETE
  88. GRB040422, optical observations at Loiano
  89. GRB040422 : I-band follow-up observation at Lulin Observatory
  90. GRB 040422: ROTSE-IIIb Prompt Optical Limits
  91. GRB040422, BVRcIc field calibration
  92. GRB 040422,optical observation
  93. GRB040422: optical and NIR observations at the VLT
  94. GRB 040422: a long GRB detected with INTEGRAL
  95. GRB 040403, deep optical observations
  96. MASTER: HETE Alert 3163, 3167 technical optical observation
  97. INTEGRAL-SPI/ACS GRB data: timing correction
  98. IBAS GRB alerts 1739, 1740, 1741
  99. HETE/IPN localization of GRB040403A (=H3143, a long burst) and GRB040403B(=H3144, a short/hard burst)
  100. GRB 040403: Optical Observations

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