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"

31730 results found.

  1. GRB 030418: Second Epoch Optical Observations with Magellan
  2. GRB030519B (=H2716): A Long, Bright GRB Localized by the HETE WXM
  3. HETE GRB030329, correction to Rc Observations in Loiano
  4. GRB 030329: Optical limit (contemporaneous imaging)
  5. GRB 030501: final TAROT limits
  6. IPN triangulation of GRB030509 (small errror box)
  7. IPN triangulation of GRB030509 - correction
  8. GRB030329: RTT150 optical observations
  9. GRB030329, BVRI photometry
  10. GRB030429, refiend optical brightness
  11. GRB 030329: Optical limit (contemporaneous photography)
  12. GRB030418, BVRcIc field photometry
  13. GRB 030429: Redshift of neighbor galaxy
  14. GRB030429, BVRcIc field photometry
  15. GRB030429: RTT150 optical obs., correction to GCN 2208
  16. GRB 030329: High-Resolution Spectroscopy of the Host
  17. GRB030429 (=H2695): A Long GRB Localized by the HETE WXM and SXC
  18. GRB030418 (=H2686): A Long, X-Ray-Rich GRB Localized by the HETE WXM
  19. XRF030416 (=U10897): An X-Ray Flash Localized by the HETE WXM
  20. GRB030429: RTT150 optical observations, a possible host galaxy
  21. GRB030329: RTT150 optical observations and upper limit for a host
  22. GRB030501, optical observation
  23. GRB030501 observation report
  24. GRB030501 triangulation (correction to GCN 2194)
  25. GRB030329: RTT150 optical observations and upper limit for a host
  26. GRB 030429: Radio Observations
  27. GRB 030429: redshift from VLT spectroscopy
  28. GRB 030429: IR photometry with IRSF/SIRIUS
  29. GRB030501B triangulation (single error box)
  30. GRB 030329 Optical Observations
  31. GRB030328, optical observation
  32. GRB 030329, BVRI photometry
  33. GRB030429: Optical Observations
  34. GRB030501: TAROT candidate afterglow present in archival images
  35. GRB 030501: TAROT possible candidate counterpart
  36. IPN triangulation of GRB030501 (IBIS event; annulus)
  37. GRB 030429: confirmation of afterglow candidate
  38. GRB030425: CrAO optical observation
  39. GRB 030329 Oprical observations in Rozhen observatory
  40. GRB 030324: Radio Observations
  41. GRB030329 observed as a sudden ionospheric disturbance (SID)
  42. GRB030329, SPM optical observations
  43. GRB 030329, the review of the sky area in plate archive (1950-1998)
  44. GRB 030329: Spectral Evolution of SN 2003dh
  45. GRB 030329: optical spectropolarimetry at VLT
  46. GRB030329: optical polarization
  47. GRB030329, optical observation
  48. GRB030329: 444 AAVSO Measurements
  49. ROTSE-III prompt optical detections of GRB 030418
  50. GRB030418: Upper limits from recent and historical observations.
  51. GRB 030418: Optical afterglow
  52. GRB 030418: Finder for afterglow candidate
  53. GRB 030329 OT position
  54. GRB030329: Optical Observations
  55. OT GRB 030329: early UBVRcIc spectral evolution
  56. GRB030329, UBVRI polarimetry, R-polarization
  57. GRB 030329: SARA Optical Observations
  58. OT GRB 030329: early spectrum
  59. GRB030329: VR Photometry at TNG
  60. GRB030324: Candidate Optical Afterglow
  61. GRB 030413: Optical Observations
  62. GRB 030329 Rc observations
  63. Superluminal motion in GRB 030329 (Correction)
  64. Superluminal motion in GRB 030329
  65. GRB 030329 and SN 2003dh
  66. GRB030329, optical position
  67. GRB 030329 VLBA Observations
  68. GRB 030329: BVRI photometry at Asiago
  69. GRB 030329, light curve flattens
  70. GRB 030329: VLT V-band photometry
  71. If the SN/GRB connection confirmed
  72. GRB 030329: Supernova Confirmed
  73. GRB030329: RTT150 optical observations
  74. GRB030329: Near Infrared Observations at Gunma
  75. GRB030329: HET spectroscopic monitoring
  76. GRB 030329, color evolution
  77. GRB030328, UBVRcIc field photometry
  78. GRB030329: Optical observcations
  79. GRB030329: BV photographic observations
  80. GRB 030329 Optical observations
  81. GRB 030329, color evolution
  82. GRB 030329: possible color change
  83. GRB030329: RTT150 optical observations
  84. GRB 030329: Supernova Spectrum Emerging
  85. GRB030329: RTT150 optical observation
  86. GRB030329: More AAVSO VR obs
  87. GRB030328: R upper limit after 6 hours by MASTER
  88. GRB 030329: BV photographic observations
  89. GRB 030329: SARA Optical Observations
  90. GRB 030329: SARA Optical Observations
  91. GRB030329, fading resumes
  92. GRB 030329, BVRI photometry
  93. GRB030329: Optical observations
  94. SDSS 0.5m PT observations of GRB030329 (correction)
  95. SDSS 0.5m PT observations of GRB030329
  96. GRB 030329, Optical observations
  97. GRB 030329, nearby galaxies
  98. GRB030329, cessation of fading
  99. GRB030329: final R-band light curve by MASTER
  100. GRB030329 Radio 23/43/90 GHz observations at Nobeyama

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