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"

16159 results found.

  1. GRB 051221A: RAPTOR Fading Counterpart Constraint
  2. GRB 051221B: BOOTES optical observations.
  3. GRB 051211A: Evidence This Is a Short Burst from Analysis of Spectral
  4. GRB 051221: Discovery of fading optical afterglow
  5. GRB 051221: Possible nearby cluster
  6. GRB 051221: IR Observations at GRB+1hr
  7. GRB051211A (=H3979): Refined Analysis
  8. GRB 051211B: optical afterglow
  9. GRB051211A: possible optical candidate
  10. GRB051105: optical observations
  11. GRB 051211B, optical observation
  12. GRB 051211a: RTT150 optical observations
  13. GRB051211B, RBO optical observations
  14. GRB 051211A: Swift/UVOT upper limits
  15. GRB 051211A,optical observation
  16. GRB 051211B: Swift XRT confirmation of the afterglow
  17. GRB051211B: Liverpool Telescope observation
  18. GRB 051211b: RTT150 optical observations
  19. GRB 051211A and GRB051211B: BOOTES simultaneous observations
  20. GRB 051211B: Swift XRT Observations
  21. GRB 051211: TAROT optical limits
  22. GRB 051211B: a possible optical detection by TAROT
  23. GRB 051211:IAC80 optical observations
  24. HETE SXC localization of GRB 051211 (=H3979)
  25. GRB 051210: Optical imaging from Las Campanas
  26. GRB051210: Swift UVOT Observation
  27. GRB051117B: optical observation
  28. GRB051111: optical observaion
  29. GRB051117b: No Swift/UVOT Detection
  30. GRB051111: Rc optical observations: correction
  31. GRB051111: Rc optical observations
  32. GRB 051109B: GAO 150cm telescope Optical limit
  33. GRB 051109A : GAO 150cm telescope Rc-band detection
  34. GRB 051021 Optical Observations
  35. GRB 051117B: MARGE Optical Limits
  36. GRB 051117B,optical observation
  37. GRB 051117B: Optical observations
  38. GRB 051117B: ROTSE-III Optical Limits
  39. GRB 051028 Optical Observations
  40. GRB050925: analysis of the XMM-Newton observation
  41. GRB051109A optical observations
  42. GRB 051111: Radio afterglow
  43. GRB 051111: AEOS optical observations
  44. GRB051111: Swift/UVOT Observations
  45. GRB 051111A : R-band temporal decay index based on Lulin
  46. GRB051111: XRT preliminary analysis
  47. GRB 051109A Optical Observations
  48. GRB 051111A : Lulin BVRI multi band afterglow observation
  49. GRB 051111A: KAIT optical observations
  50. GRB 051111: ROTSE-III Analysis of Prompt Counterpart
  51. GRB 051109A
  52. GRB 051105a: GETS optical limit
  53. GRB 051109A: KAIT optical observations
  54. Early RAPTOR measurements of GRB 051109a - the movie.
  55. GRB 051109B: ROTSE-III Optical Limits
  56. GRB 051109A: Swift-UVOT Observations
  57. GRB 051109B : Lulin Optical Observations
  58. GRB 051109A : Lulin BVRI Optical afterglow observation
  59. GRB051109A: XRT refined analysis
  60. GRB 051109a: BOOTES R & I-band detection of the early afterglow
  61. GRB 051109B Kiso optical follow-up observation
  62. GRB051105B: REM Optical observation
  63. GRB 051109: HET Optical Spectrum and Absorption Redshift
  64. GRB 051109: Rc and Ic observations
  65. GRB 051109a: IR Photometry and Astrometry
  66. GRB 051109A: ROTSE-III Decline rate for Optical Counterpart
  67. GRB051105B: Swift/XRT upper limit
  68. GRB051103: optical observations
  69. GRB 051103, optical observations
  70. GRB051103: MASTER: OT limit and host galaxy candidates
  71. GRB051028: Swift-XRT refined analysis
  72. GRB 051105a, observation from Naini Tal and OSN
  73. GRB 051105A, 2nd epoch optical observations
  74. GRB 051105A: TNG optical observations
  75. GRB051105A: Swift/UVOT Observations
  76. GRB 051105A, optical observations
  77. GRB 051105b: ART optical limits
  78. GRB 051105B (INTEGRAL 2701): Optical observation
  79. GRB 051105: Optical limit
  80. GRB 051016B host spectroscopy and redshift
  81. GRB051016B: optical observation
  82. Recent GRB UBVRcIc field photometry
  83. GRB 051022: RTT150 optical observations
  84. GRB 051021A: RTT150 optical observations
  85. GRB051028: optical observations
  86. GRB051028: confirmation of the afterglow
  87. GRB051028: WHT optical candidate
  88. GRB 051028 (=H3951): A GRB localized by HETE
  89. GRB051028:MASTER optical observations
  90. GRB 051022: XRT Refined Spectral and Temporal Analysis--Correction
  91. SGR 1806-20: continued moderate activity seen with INTEGRAL
  92. GRB 051021, Optical Observations
  93. GRB 051022: XRT Refined Spectral and Temporal Analysis
  94. GRB 051022, refined optical astrometry
  95. GRB051021B: Swift XRT refined analysis
  96. GRB051021a: optical observations
  97. GRB051021A: Swift XRT refined analysis
  98. GRB051022: Optical Observations
  99. GRB 051022: Spectral Analysis Indicates That The Spectrum Is Absorbed
  100. GRB 051021, SMARTS optical/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