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"

16155 results found.

  1. GRB 110503A: optical observation in CrAO
  2. GRB 110503A: Millimeter observation from SMA
  3. GRB 110503A: Swift/UVOT Observations
  4. GRB 110503A: PAIRITEL NIR Detection
  5. GRB 110503A: redshift confirmation from TNG
  6. GRB 110503A: NOT afterglow photometry
  7. GRB 110503A: Swift detection of a burst with a bright optical counterpart
  8. GRB 110428A : X-ray afterglow confirmation
  9. GRB 110422A: optical observations in CrAO
  10. GRB 110422A: Update of Herschel FIR observation schedule
  11. GRB 110422A: optical observations in CrAO, second epoch
  12. GRB110422A: NOT optical follow-ups
  13. GRB 110422A: optical observations in CrAO
  14. GRB110422A: MITSuME Ishigakijima Optical Observation
  15. GRB 110422A: Further NOT observation
  16. GRB 110422A: Swift/UVOT Detection of optical afterglow
  17. GRB 110422A: THO optical observations
  18. GRB 110422A: TNG optical observations
  19. GRB 110422A: SAO RAS optical observations
  20. GRB 110422A: NOT optical observation
  21. GRB 110422A: MASTER earlier OT polarization observations
  22. GRB 110422A: Mondy optical observations
  23. GRB 110328A/Swift J164449.3+573451: Maidanak Optical Observation
  24. GRB 110420B: Swift/UVOT Upper Limits
  25. GRB110420A: GROND detection of the Optical/NIR Afterglow Candidate
  26. GRB 110420A Swift/UVOT Observations
  27. GRB 110420A: Swift detection of a burst with optical counterpart
  28. GRB110414A: MITSuME Ishigakijima Optical upper limits
  29. GRB 110414A: GROND upper limits
  30. GRB110414A: MITSuME Okayama Optical upper limits
  31. GRB 110414A: Swift/UVOT Upper limits
  32. GRB 110411A: PAIRITEL NIR Upper Limits
  33. GRB 110411A: optical limits from OSN
  34. GRB 110411A: Swift/UVOT Upper Limits
  35. GRB 110411A: MASTER prompt and follow-up optical limits
  36. GRB 110411A : Xinglong TNT OT candidate
  37. GRB 110411A: MASTER optical observations
  38. GRB 110328A / Swift J164449.3+573451: R-band Monitoring
  39. GRB 110328A / Swift J164449.3+573451: MASTER pre, prompt and follow-up observations
  40. GRB 110328A / Swift J164449.3+573451: optical observations
  41. GRB 110407A: SMARTS optical limit
  42. GRB 110407A: MASTER optical observations
  43. GRB110407A: UVOT Upper Limits
  44. GRB 110407A: GROND Detection of the Optical Afterglow
  45. GRB 110407A: MITSuME Okayama and Ishigakijima Optical upper limits
  46. GRB 110407A: NOT optical observations
  47. GRB 100407A : Errata of afterglow position in GCN 11899
  48. GRB 110407A : Lulin optical afterglow detection
  49. GRB 110407A: MASTER early optical observations
  50. GRB 110402A: fading optical afterglow
  51. GRB 110328/Swift J164449.3+573451: Chandra observations
  52. GRB 110402A: LOAO Optical Observation
  53. GRB 110328A / Swift J164449.3+573451: Keck LRIS R-band photometry
  54. GRB 110328A / Swift J164449.3+573451, HST Observations
  55. GRB 110402A: optical observations in Mondy
  56. GRB 110328A / Swift J164449.3+573451: Keck/DEIMOS Optical Spectroscopy
  57. GRB 110402A: MITSuME Okayama and Ishigakijima Optical upper limits
  58. GRB 110328A/Swift J164449.3+573451: SARA-N detection
  59. GRB 110402A: early optical limit by "Pi of the Sky"
  60. GRB 110402A: further NOT observations
  61. GRB110328A/Swift J164449.3+573451: Fermi LAT Observations
  62. GRB 110402A: PAIRITEL NIR Upper Limits
  63. GRB 110402A: NOT afterglow confirmation
  64. GRB 110328A / Swift J164449.3+573451: KASINICS NIR Observation
  65. GRB 110328A / Swift J164449.3+573451: Radio-optical/NIR Astrometry
  66. GRB 110328A / Swift J164449.3+573451: Infrared transient
  67. GRB 110328A / Swift J164449.3+573451: Mondy optical observations
  68. GRB 110328A / Swift J164449.3+573451: EVLA observations of a brightening radio source
  69. GRB 110328A / Swift J164449.3+573451: PAIRITEL NIR Detection in 2nd Epoch
  70. GRB 110328A / Swift J164449.3+573451: No optical variability of the optical counterpart
  71. GRB 110328A / Swift J164449.3+573451: BAT refined analysis
  72. GRB 110328A / Swift J164449.3+573451: LOAO R-band Observation
  73. GRB 110328A / Swift J164449.3+573451: PAIRITEL NIR Upper Limits
  74. GRB 110328A / Swift J164449.3+573451: optical observations
  75. GRB 110328A / Swift J164449.3+573451: EVLA Detection
  76. GRB 110328A / Swift J164449.3+573451: optical spectroscopy from GTC
  77. GRB 110328A: Gemini spectroscopic observations
  78. GRB 110328A / Swift J164449.3+573451: NOT optical observations.
  79. GRB 110328A/ Swift J164449.3+573451 : Xinglong TNT Upper limit
  80. GRB / X-ray transient 110328A: MITSuME OkayamaOptical upper limits
  81. GRB 110328A / Swift J164449.3+573451: PTF Quiescent Optical Counterpart
  82. GRB / X-ray transient 110328A: Gemini optical observations
  83. GRB110318B : MOA optical upper limit
  84. GRB 101225A: revised analysis of narrow band imaging
  85. GRB 110319B: Swift/UVOT Upper Limits
  86. GRB 110318B: Swift/UVOT Upper Limits
  87. GRB 110319A: Swift/UVOT Detection
  88. GRB 110315A: RTT150 optical observations
  89. GRB 110315A: Swift/UVOT Upper Limits
  90. GRB 110315A: MASTER early optical observations
  91. GRB110312A: MITSuME Okayama Optical upper limits
  92. GRB 110312A: RTT150 optical observations
  93. GRB 110312A: Swift/UVOT Upper Limits
  94. GRB 110312A: GROND Upper Limits
  95. GRB 110305A: REM detection of a possible NIR afterglow
  96. GRB110305A: MITSuME Ishigakijima Optical upper limits
  97. GRB 110305A: Swift/UVOT Upper Limits
  98. GRB 110305A: GROND Detection of Optical Afterglow
  99. GRB 110223A: optical upper limits
  100. Swift/UVOT observations of GRB110223A

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