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"

28039 results found.

  1. XRF030723, BVRcIc field photometry update
  2. IPN triangulation of GRB030801 (large error box)
  3. GRB021206 optical counterpart upper limit
  4. IPN triangulation of GRB030726 (large error box)
  5. IPN triangulation of GRB030721 (large error box)
  6. XRF030723 Radio Observations
  7. XRF 030723: confirmation of fading optical counterpart
  8. XRF030723(=H2777): Chandra Observations
  9. GRB030723: Upper limits from historical observations
  10. XRF030723: Palomar observations and proposed counterpart
  11. GRB030725 (=H2779): A Bright GRB Localized by HETE
  12. XRF030723 (= H2777): Chandra Observations Scheduled
  13. XRF030723, BVRcIc field photometry correction
  14. XRF030723, ROTSE-III Early Observations
  15. XRF030723, BVRcIc field photometry
  16. XRF 030723, optical observations
  17. XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and
  18. Konus-Wind detection of the bursts from SGR1806-20 region
  19. SGR 1806-20, submm observations
  20. RXTE PCA Observations of SGR1806-20 Region
  21. IPN triangulation of GRB030714 (two large error boxes)
  22. IPN triangulation of GRB030715 (two large error boxes)
  23. GRB030706 triangulation (single large error box)
  24. GRB030329, optical observation in May
  25. IPN triangulation of GRB030626 (single large error box)
  26. IPN triangulation of GRB030626 (two large error boxes)
  27. GRB030329: second XMM-Newton observation
  28. GRB030329 -- RATAN-600 data in April-May
  29. GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
  30. IPN triangulation of GRB030606 (two alternate error boxes)
  31. GRB 030528: Infrared Observations and the Proposed IR Counterpart
  32. GRB 030528: tentative NIR counterpart
  33. GRB030528(=H2724): Observations with the Chandra X-ray Observatory
  34. GRB030528, BVRI field photometry
  35. GRB030329, SPM optical observations
  36. GRB030528: Chandra TOO Planned
  37. GRB030528(=H2724): Revised SXC Localization
  38. GRB 030528 Bisei optical observation
  39. GRB030528 (H2724): A long GRB localized by HETE
  40. GRB 030329: Correction to GCN 2254
  41. GRB 030329: Optical Observations
  42. GRB 030528 (=H2724) Kyoto optical observation
  43. GRB 030416: Optical Observations
  44. GRB 030329 Optical Observations
  45. GRB030329: XMM-Newton observation
  46. GRB 021004: HST observations
  47. GRB030324: Further Observations of the Candidate Optical Afterglow
  48. GRB030519B (=H2716): Peak Fluxes, Fluences, and Energy Spectrum
  49. IPN triangulation of GRB030519B=H2716 (small error box)
  50. HETE GRB030329, correction to Rc Observations in Loiano
  51. GRB 030329: Optical limit (contemporaneous imaging)
  52. IPN triangulation of GRB030509 (small errror box)
  53. GRB030329, BVRI photometry
  54. GRB030429, refiend optical brightness
  55. GRB 030329: Optical limit (contemporaneous photography)
  56. GRB030418, BVRcIc field photometry
  57. GRB030429, BVRcIc field photometry
  58. GRB030429 (=H2695): A Long GRB Localized by the HETE WXM and SXC
  59. XRF030416 (=U10897): An X-Ray Flash Localized by the HETE WXM
  60. GRB030329: RTT150 optical observations and upper limit for a host
  61. GRB030501, optical observation
  62. GRB030501 triangulation (correction to GCN 2194)
  63. GRB030329: RTT150 optical observations and upper limit for a host
  64. GRB 030429: redshift from VLT spectroscopy
  65. GRB030501B triangulation (single error box)
  66. GRB 030329, BVRI photometry
  67. GRB030429: Optical Observations
  68. GRB030501: TAROT candidate afterglow present in archival images
  69. GRB 030429: confirmation of afterglow candidate
  70. GRB 030329 Oprical observations in Rozhen observatory
  71. SNeIa AS THE POSSIBLE PROGENITORS OF SHORT-DURATION GRBs.
  72. IPN triangulation of GRB030425 (single error box)
  73. GRB 030329, the review of the sky area in plate archive (1950-1998)
  74. GRB 030329: optical spectropolarimetry at VLT
  75. GRB 030329: wide-field photograph by R. Tamura 1 hr after the burst
  76. GRB030329: optical polarization
  77. IPN triangulation of GRB030422 (two large error boxes)
  78. GRB030329, optical observation
  79. MASTER:optical observations GRB030418
  80. MASTER:optical observations probable GRB030414
  81. GRB030418: Kiso near infrared observations
  82. GRB 030418: Optical afterglow
  83. OT GRB 030329: early UBVRcIc spectral evolution
  84. OT GRB 030329: early spectrum
  85. IPN triangulation of GRB030414 (small error box)
  86. IPN triangulation of GRB030413 (small error box)
  87. Superluminal motion in GRB 030329 (Correction)
  88. Superluminal motion in GRB 030329
  89. GRB030329, optical position
  90. IPN triangulation of GRB030406 (small error box)
  91. IPN triangulation of GRB050403 (small error box)
  92. GRB 030329: BVRI photometry at Asiago
  93. GRB 030329: VLT V-band photometry
  94. Kiso observation of the GRB030329 at April 6
  95. GRB 030329, color evolution
  96. GRB030328, UBVRcIc field photometry
  97. GRB 030329 Optical observations
  98. GRB030329: Kiso B and R band observations
  99. GRB030328: R upper limit after 6 hours by MASTER
  100. SDSS 0.5m PT observations of GRB030329 (correction)

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