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"

31731 results found.

  1. Further Swift-BAT analysis of GRB 071227
  2. Konus-Wind observation of GRB 071227
  3. GRB 071227: Magellan redshift confirmation
  4. GRB 071227: Swift-XRT refined analysis
  5. GRB 071227: VLT probable redshift of the candidate host galaxy
  6. GRB 071227: Magellan observations
  7. GRB071227: Swift/UVOT refined analysis
  8. GRB 071227: REM NIR and Optical observations
  9. Swift-BAT refined analysis of short GRB 071227
  10. GRB071020: optical observations
  11. GRB 070429B: Possible UVOT Detection of an Optical Afterglow
  12. Swift-BAT trigger 298308 is not a GRB
  13. GRB 071125: Suzaku WAM observation of the prompt emission
  14. GRB 070429B: Probable host galaxy and redshift
  15. GRB 071129, Swift-BAT refined analysis
  16. Konus-Wind and Konus-A observations of GRB 071125
  17. GRB 071112C: Optical/NIR observations
  18. Disregard the "GRB 071126" position
  19. VLA radio detection of GRB 071122
  20. GRB071122: Swift/UVOT Observations
  21. GRB071104: NIR Afterglow Candidate at TNG
  22. GRB 071122: MASTER optical observation
  23. GRB 071122, Swift-BAT refined analysis
  24. GRB 071122 Swift XRT position update sent in error.
  25. GRB 071122 Swift-XRT refined analysis
  26. GRB 071122: Corrected P60 Coordinates
  27. GRB071122: Gemini Absorption redshift
  28. GRB 071122: P60 Optical Afterglow Candidate
  29. GRB 071122: ROTSE-III Optical Limits
  30. GRB 071118: P60 Observations
  31. GRB071118 MITSuME OAO optical observation
  32. GRB 071118: Observations from OSN
  33. GRB 071117: VLT observations and probable redshift
  34. Swift/UVOT observations of GRB071118
  35. GRB 071117: Swift-XRT revised position
  36. Konus-Wind and Konus-A observations of GRB 071117
  37. Swift XRT follow-up observations of GRB071008
  38. Swift/UVOT upper limits for GRB 071117
  39. GRB071118: Swift XRT refined analysis
  40. GRB 071117: Gemini Optical Afterglow Discovery
  41. GRB 071118, Swift-BAT refined analysis
  42. GRB 071112B: Gemini Image Differencing
  43. GRB 071117: Gemini Observations
  44. GRB 071117: Swift-XRT refined analysis
  45. GRB 071117, Swift-BAT refined analysis
  46. VLT FORS2 observations of short hard GRB071112B
  47. GRB 071117: Swift/XRT position
  48. VLA radio upper limit on GRB 071112C
  49. ATCA radio observations of short hard burst GRB 071112B
  50. GRB 071112C: Optical and NIR data observed with KANATA
  51. Correction to the Swift-BAT Transient Identification (trigger=296683)
  52. GRB 071112C: WSRT Radio Observations
  53. GRB071112C: Errata of MITSuME Ic band photometry
  54. GRB 071112C: optical observation
  55. GRB 071112C: optical observation
  56. GRB 071112C: emission lines and refined VLT redshift
  57. GRB 071112C MITSuME Akeno early optical observation
  58. GRB 071112C: Gemini Absorption Redshift
  59. GRB 071112B: 2nd epoch of Magellan i-band imaging
  60. GRB 071112C: SARA upper limit
  61. GRB 071112C : Second Epoch Lulin R-band observations
  62. GRB071112C MITSuME Okayama Optical Observation
  63. GRB 071112C: Swift-BAT refined analysis
  64. GRB 071112C: Swift/UVOT observations
  65. GRB 071112C: Swift XRT refined analysis
  66. GRB 071112C: Optical observations at Crni Vrh
  67. Swift UVOT upper limits of GRB071112B
  68. GRB 071112C: VLT redshift
  69. GRB 071112B: Magellan i-band imaging
  70. GRB 071112B: Gemini Optical Imaging (Correction)
  71. GRB 071112B: Gemini Optical Imaging
  72. GRB 071112B: Swift-XRT preliminary analysis
  73. GRB 071112B, Swift-BAT partial refined analysis of the SHB
  74. GRB071112C: NOT observations
  75. GRB 071112C: Palomar Pre-Imaging
  76. Swift-BAT trigger 296491 is not a GRB
  77. GRB 071112C : Lulin R-band observation
  78. GRB 071112C: RTT150 optical observations
  79. Swift XRT follow-up observations of GRB071028B
  80. GRB071112C Xinglong_TNT_and_EST_afterglow observations
  81. GRB 071112C: Optical and NIR afterglows observed with KANATA
  82. GRB 071112C: ROTSE-III Confirmation of Optical Counterpart
  83. GRB 071112B: ROTSE-III Rapid Optical Limits
  84. GRB071109: Super-LOTIS observations
  85. VLA IInd observation of INTEGRAL burst GRB 071109
  86. Swift/UVOT initial analysis of GRB071109
  87. GRB 071109: further Swift-XRT analysis
  88. No radio detection at Swift-XRT position
  89. GRB 071109: Swift-XRT possible X-ray counterpart
  90. VLA prompt radio detection of the INTEGRAL burst 071109
  91. GRB 071109: IBIS refined analysis
  92. GRB 071109: BOOTES-2 prompt optical observations
  93. GRB 071104: Swift-XRT Team Refined Analysis
  94. GRB 071104: Possible Swift UVOT Afterglow Candidate
  95. GRB 071104: Swift-XRT position
  96. GRB071010b: optical observation
  97. Swift XRT and UVOT observations of GRB071028B
  98. GRB 071101, Swift-BAT refined analysis
  99. GRB 071101: Swift-XRT Team refined analysis
  100. GRB071101: Optical and NIR upper limits by KANATA

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