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"

8476 results found.

  1. GRB040323: NIR Observations and Variable Object
  2. GRB 031203: spectoscopic evidence for a 1998bw-like SN
  3. MASTER: RXTE GRB040308 optical observation
  4. RXTE GRB040229 optical observation: no candidate
  5. GRB 040228 Optical observations
  6. GRB031220: 2nd Chandra observation and X-ray afterglow candidate
  7. GRB031203: Chandra Observations
  8. GRB040106: Second Epoch Optical Observations
  9. GRB 031220: Optical observations of Chandra X-ray sources
  10. GRB031220 : Optical Observation of Lulin Observatory
  11. GRB 031203 I-band monitoring
  12. GRB 2974 follow-up observations
  13. GRB 021203: A Normal GRB viewed far off axis?
  14. GRB 031203: z ~ 10 or Fragmented Dust in the Circumburst Environment?
  15. GRB 031111: Optical observations
  16. SN 2003jd (SN/GRB?) - possible association with GRB 030929
  17. GRB 031026 (=H2882): Evidence for High Redshift from Prompt
  18. GRB030913: Subaru Optical Observations
  19. GRB030913, candidate afterglow observations
  20. GRB 030913, optical candidate
  21. GRB 030824: Candidate Follow-Up
  22. XRF030824: optical observations
  23. XRF030824: Palomar observations
  24. GRB 030824: Candidate Afterglow (or Variable/Flare Star?)
  25. RAPTOR observations of GRB030823
  26. Summary of recent IPN and HETE detections of SGR bursts
  27. GRB 021206 Optical Observations
  28. GRB030725: Optical observations
  29. XRF030723: Re-analysis of ROTSE-III early images
  30. GRB030725, optical transient observations
  31. XRF 030723: VLT spectra
  32. XRF030723: Palomar observations and proposed counterpart
  33. GRB030725 (=H2779): A Bright GRB Localized by HETE
  34. RXTE PCA Observations of SGR1806-20 Region
  35. GRB 021206, Radio afterglow candidate
  36. GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
  37. GRB 030519B: optical observations.
  38. GRB 030528: Optical observations at RIKEN
  39. GRB 030329: HST ACS Observations of the Host
  40. GRB030324: Further Observations of the Candidate Optical Afterglow
  41. GRB 030418: Second Epoch Optical Observations with Magellan
  42. GRB030429: RTT150 optical observations, a possible host galaxy
  43. GRB030329: RTT150 optical observations and upper limit for a host
  44. GRB 030429: IR photometry with IRSF/SIRIUS
  45. GRB030501: TAROT candidate afterglow present in archival images
  46. GRB 030501: TAROT possible candidate counterpart
  47. GRB 030429: confirmation of afterglow candidate
  48. GRB030429, possible optical counterpart
  49. GRB 030429: ROTSE-III observations
  50. GRB030329, SPM optical observations
  51. Optical Observations of GRB 030418 with Magellan
  52. GRB 030418: Optical afterglow
  53. GRB 030418: Finder for afterglow candidate
  54. GRB 030418: Optical afterglow candidate
  55. GRB030324: Candidate Optical Afterglow (Erratum)
  56. GRB030324: Candidate Optical Afterglow
  57. GRB030329: HET spectroscopic monitoring
  58. GRB 030329: precise position from Kyoto images
  59. GRB 030329: Optical afterglow fading
  60. GRB 030329 follow-up
  61. GRB 030329: Optical afterglow candidate
  62. GRB 030329: OT candidate
  63. GRB 030329: Optical afterglow candidate
  64. GRB 030328: Finding chart
  65. GRB 030328: Optical afterglow candidate
  66. GRB030324 optical observation
  67. GRB030131, BVRcIc field photometry
  68. GRB030324, optical observations
  69. GRB030324, optical observations
  70. GRB030323: V, R, I photometry
  71. VLT/FORS2 spectra of GRB 030323
  72. GRB030323, ROTSE-III detection of possible optical counterpart
  73. GRB030323, optical observations
  74. GRB030323, possible optical counterpart
  75. IPN upper limit to a GRB associated with SN2003L
  76. GRB 030227 optical afterglow
  77. GRB 030227: Confirmed Optical Afterglow (S1-A)
  78. GRB 030227: fading of candidate optical afterglow 'S1-A'
  79. GRB 030227, possible optical counterpart of XMM-Newton source
  80. GRB030227 - faint tentative OT candidate
  81. GRB 030226: Optical afterglow
  82. GRB030226: Candidate optical afterglow
  83. GRB: Non-Referencing of GCN Circulars.
  84. GRB 030131: marginal optical detection
  85. GRB030131: Candidate Optical Afterglow
  86. GRB 030131, optical observations
  87. GRB030131: Kiso optical limit for corrected position
  88. GRB030131: Optical limits for corrected position
  89. GRB 030131: afterglow candidate
  90. GRB 020819: afterglow candidate
  91. GRB030115: 1.2 mm upper limits with MAMBO @ IRAM 30m
  92. GRB030115 submm upper limit
  93. GRB 030115: Further IR observations with IRSF/SIRIUS
  94. Publicizing GRB Discoveries - A Message from NASA HQ
  95. GRB 030115: Radio detection of IR candidate
  96. GRB 030115: IR observations with IRSF/SIRIUS
  97. GRB030115: R-band counterpart of IR candidate
  98. GRB030115, afterglow candidate
  99. GRB 021211: R-band observations at late-time
  100. GRB 030115, no optical candidate

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