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"

6791 results found.

  1. GRB 040730: Optical observations
  2. XRF 040701, optical observations
  3. SGR 1806-20: no IR variability of the proposed counterparts
  4. SGR 1806-20, potential NIR counterpart
  5. GRB 040511: NIR observations with REM
  6. GRB 040511: Optical Observations
  7. GRB040422 : I-band follow-up observation at Lulin Observatory
  8. GRB 040403: Optical Observations
  9. GRB 040323, a dark GRB ?
  10. GRB 040323: a long GRB detected with INTEGRAL
  11. GRB040223: Deep NIR NTT data re-analysis
  12. GRB040228 : KISO optical follow-up observation
  13. GRB 040223: Deep NIR NTT observations
  14. GRB 040223 : Optical observation (non-detection)
  15. GRB 040223: REM IJK Observations
  16. GRB 040223 XMM-Newton observation ...
  17. GRB 031203 XMM-Newton observation
  18. GRB031203: ROSAT upper limits suggest XMM-S1 source as the transient
  19. XMM-Newton Observation of GRB031203
  20. GRB 031203: Deep NIR NTT & VLT observations
  21. XMM-Newton Observation of GRB031203
  22. GRB 031203: IR NTTobservations do not confirm REM detection
  23. GRB031203 : Optical Observation of Lulin Observatory
  24. GRB 031203: z ~ 10 or Fragmented Dust in the Circumburst Environment?
  25. GRB 031203: IR REM Observations
  26. GRB 031203 XMM-Newton observation
  27. IPN/HETE localization of GRB031109 (=H2917; large error box)
  28. GRB 031111: Optical observations
  29. Lulin optical follow-up observations of GRB031026
  30. GRB031026 : KISO optical follow-up observation
  31. XRF 030824: additional observations at CFHT
  32. XRF 030824: observations at CFHT
  33. Magellan Observations of GRB030725 (=H2779)
  34. XRF030723: Palomar observations and proposed counterpart
  35. XRF 030723, optical observations
  36. Konus-Wind detection of the bursts from SGR1806-20 region
  37. GRB030329: second XMM-Newton observation
  38. GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
  39. GRB 030528: Infrared Observations and the Proposed IR Counterpart
  40. GRB 030528: tentative NIR counterpart
  41. GRB 030416: Optical Observations
  42. GRB 030329: Optical limit (contemporaneous photography)
  43. GRB 030429: IR photometry with IRSF/SIRIUS
  44. GRB030501: TAROT candidate afterglow present in archival images
  45. GRB 030429: confirmation of afterglow candidate
  46. GRB 030329 Oprical observations in Rozhen observatory
  47. GRB030418: Kiso near infrared observations
  48. IPN triangulation of GRB030410 (annulus)
  49. GRB030329: Near Infrared Observations at Gunma
  50. GRB 030329 Optical observations
  51. GRB 030329, BVRI photometry
  52. GRB030329: Optical observations
  53. GRB030329, optical observation
  54. GRB030329, optical observation
  55. GRB 030329, BRI photometry
  56. GRB 030329: fading X-ray afterglow with RXTE
  57. GRB 030324: Optical and NIR Observations
  58. GRB030329: R and B observations
  59. GRB 030329: OT B and R photometry, decline rate
  60. GRB030329: Upper limits from recent and historical observations.
  61. GRB 030328: optical observations
  62. GRB 030328: OT photometry
  63. GRB030323: Detection on 2003/03/24
  64. GRB 030320: Optical Observations
  65. GRB 030324, optical observations
  66. GRB030226, addendum to GCN 1892
  67. GRB 030226 Optical observations
  68. GRB 030226: Ic Observations
  69. XMM-Newton observation of GRB030227
  70. GRB 030226: Confirmed decay index
  71. GRB030217: optical observations
  72. GRB 030204: Optical Observations
  73. GRB020819: Kiso R and I band observations
  74. GRB 030204, optical observations
  75. GRB030131: Kiso optical limit for corrected position
  76. GRB030131: Kiso Observations
  77. GRB 030115: Further IR observations with IRSF/SIRIUS
  78. GRB 030115: IR observations with IRSF/SIRIUS
  79. GRB 021219: OSN optical observations
  80. GRB021211: Kiso Observations
  81. GRB021204: Kiso Observations
  82. Chandra observation of the IPN error box of GRB021201 (short/hard)
  83. GRB021113: Kiso Observations
  84. Detection of activity from SGR 1900+14 with the RXTE/PCA
  85. GRB 021023: Curious K-band Source(s) Just Outside of IPN Localization
  86. GRB021004: High-resolution optical spectroscopy
  87. XRF 020903 spectrum
  88. GRB 021004 redshift
  89. HETE fluences for GRB021004
  90. GRB 021004: Optical Observations
  91. GRB021004: Optical Spectroscopy
  92. XRF 020903: Correction to GCN 1560
  93. XRF 020903: VRI observations
  94. GRB020812: optical observations
  95. GRB 020813 multiband optical observations
  96. GRB/XRF 020427, detection of an underlying system with the VLT
  97. SGR-like X-ray Bursts from AXP 1E 2259+586: follow-up
  98. SGR-like Bursts from the AXP 1E 2259+586
  99. GRB 020531/Candidate Redshift
  100. GRB 020418, optical/near-IR 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