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"

20901 results found.

  1. GRB 130603B: Afterglow detection from NOT
  2. GRB 130603B: WHT optical afterglow candidate
  3. Swift/UVOT observations of GRB130603A
  4. GRB 130603A: Swift-XRT observations
  5. GRB 130529A: GROND upper limits
  6. GRB 130529A: Swift/UVOT Upper Limits
  7. GRB 130528A: Swift/UVOT Upper Limits
  8. GRB 130527A: Swift/UVOT Upper Limits
  9. GRB 130521A: Skynet/PROMPT detection of an extremely red afterglow
  10. GRB 130527A: NOT optical counterpart
  11. GRB 130527A: RATIR Optical and NIR Observations
  12. GRB 130527A: BOOTES-2 & 3.5m CAHA opt/nIR observations
  13. Swift Trigger 556533 is not an astrophysical event
  14. GRB 130521A: Skynet/PROMPT observations
  15. GRB 130514B: Further Swift-XRT Observations
  16. GRB 130521A: TAROT La Silla observatory optical observations
  17. GRB 130518A: mm detection at PdBI
  18. GRB 130518A: Gemini Redshift confirmation
  19. GRB 130427A / SN 2013cq: Hubble Space Telescope Observations
  20. GRB 130518A: 10.4m GTC/OSIRIS redshift
  21. GRB 130518A: Continued RATIR Optical Observations - Fading
  22. GRB 130518A: Confirmation of the X-ray afterglow.
  23. GRB 130518A: P60 Afterglow Observations
  24. GRB 130518A: RATIR Optical and NIR Observations
  25. GRB 130518A: Swift XRT and UVOT possible afterglow
  26. VLT observations of GRB 130427A
  27. GRB 130427A: Konkoly optical observations
  28. GRB 130515A: Further Gemini Observations
  29. GRB 130427A:: BTA spectroscopic observations on May 10/11.
  30. GRB 130515A: FORS2 spectroscopy of candidate counterpart
  31. GRB 130427A: Continued RATIR Optical and NIR Observations - Photometric Evidence for a New Component
  32. GRB 130514B: RATIR Optical and NIR Observations
  33. GRB 130427A: Skynet detections of a possible supernova
  34. GRB 130515A: Swift/UVOT Upper Limits
  35. GRB 130514B Swift-BAT observations
  36. GRB 130514B: GROND observations
  37. GRB 130515A: Gemini/GMOS Observations
  38. GRB 130515A: GROND Observations
  39. GRB 130514B: Swift-XRT Observations
  40. GRB 130514A: Skynet/PROMPT/DSO Detections
  41. GRB 130513A: Bassano Bresciano optical upper limit
  42. GRB 130427A: Spectroscopic detection of the SN from the 10.4m GTC
  43. GRB 130427A: optical observations
  44. GRB130514B: MASTER-Net optical observations.
  45. GRB 130514A: RATIR Optical and NIR Observations
  46. GRB 130513A: RATIR Optical and NIR Observations
  47. GRB 130513A: Swift/UVOT Upper Limits
  48. GRB 130514A: Swift/UVOT Upper Limits
  49. GRB 130513A: GROND observations
  50. GRB 130514A: GROND optical-NIR afterglow discovery and photo-z
  51. GRB 130514A: P60 Observations
  52. GRB 130427A: Tautenburg 2nd epoch: No break, no clear SN
  53. GRB130508A: MASTER-Net optical observations
  54. GRB 130511A: Kanata/HOWPol optical observation
  55. GRB 130508A: Swift/UVOT Upper Limits
  56. GRB 130427A: host galaxy observations
  57. GRB 130508A: RATIR Optical and NIR Observations
  58. GRB 130427A: Keck/LRIS Observations
  59. GRB 130427A: Ten nights of Skynet/PROMPT/GORT observations
  60. GRB 130427A: Continued RATIR Optical and NIR Observations
  61. GRB 130505B: Further Swift observations
  62. GRB 130427A: Excess optical emission consistent with an emerging supernova
  63. GRB 130427A: Amateur observations from Sweden
  64. GRB 130505A: RATIR Optical and NIR Observations
  65. GRB 130505B: Swift Candidate Afterglow
  66. GRB 130505A: Tautenburg afterglow observations
  67. GRB 130427A: Tautenburg afterglow observations
  68. GRB 130427A: RHESSI observations
  69. GRB 130504C: further Swift-XRT observations
  70. GRB 130505A: optical observations
  71. GRB 130504C: Swift-XRT observations
  72. GRB 130427A: optical observations in CrAO
  73. Swift/UVOT observations of GRB130505A
  74. GRB 130505A: iTelescope T12 optical observations
  75. GRB 130505A: Xinglong TNT optical observations
  76. GRB 130505A; Weihai optical observations
  77. GRB 130504A: IAC80 optical candidate
  78. GRB 130504A: Bassano Bresciano Observatory optical upper limit
  79. GRB 130504A: Swift/UVOT Upper Limits
  80. GRB 130502B: possible TNG counterpart
  81. GRB 130427A: Non-observation of VHE emission with HAWC
  82. GRB130502A: MASTER-Net optical observations
  83. GRB 130502B: Swift/UVOT Upper Limits
  84. GRB 130502A: Swift/UVOT Upper Limits
  85. GRB 130502B: P60 Observations
  86. GRB 130502B Swift-XRT observations
  87. GRB 130502A: RATIR Optical and NIR Observations
  88. GRB 130427A: Pan-STARRS 1 optical observations
  89. GRB 130418A: TNG NIR observations
  90. GRB 130502A: OSN and IAC80 I-band observations
  91. GRB 130502A: z-band observations from GTC
  92. GRB 130502A: TNG candidate counterpart
  93. GRB 130502A: T100 Observations
  94. GRB 130427A: Predictions about the occurrence of a supernova
  95. GRB 130427A: KAIT optical observations
  96. GRB 130427A: SARA-N optical observations
  97. GRB 130427A: VLA 20 GHz detection
  98. GRB 130427A: ABT optical observations
  99. GRB 130427A: GMRT radio detection
  100. GRB 130427A: Continued GMG optical 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