Skip to main content
JSON Notices via Email, Kafka Cron Jobs, Submitter Profile, GCN is Hiring. See news and announcements

GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

16272 results found.

  1. Fermi 424934131 / iPTF14cva: Discovery and Redshift of Optical Afterglow
  2. GRB 140610A: TShAO optical upper limit
  3. GRB 140619A: Swift detection of a burst with a possible optical counterpart
  4. GRB 140606A: BTA and OSN optical observations
  5. GRB 140614C: 1.23m CAHA (+EDIPO) observations
  6. GRB 140614B: MITSuME Akeno upper limits
  7. GRB 140614B: MITSuME Okayama upper limits
  8. GRB 140606B / iPTF 14bfu: Mondy optical observations
  9. GRB 140614A: X-shooter redshift
  10. GRB 140614B: Swift/UVOT Upper Limits
  11. GRB 140614B: RATIR Optical and NIR Observations
  12. GRB 140606B / iPTF 14bfu: AAO optical observations
  13. GRB 140614A: Swift/UVOT Upper Limits
  14. GRB 140606B / iPTF 14bfu: MOSFIRE NIR imaging
  15. GRB 140610A: RATIR Optical and NIR Observations
  16. GRB 140610A: MASTER optical observations
  17. GRB 140610A: Swift/UVOT Upper Limits
  18. GRB140606B: DCT time of observation correction
  19. GRB 140606B: Swift XRT refined analysis
  20. GRB 140521A: AAO optical upper limit
  21. GRB 140606A: AAO optical upper limit
  22. IPN Triangulation of GRB 140606B
  23. GRB 140606B: Swift/UVOT Upper Limits
  24. GRB140606B/iPTF14bfu: Discovery Channel Telescope Optical Detection
  25. GRB 140606B / Fermi 432717114 / iPTF 14bfu: Keck redshift
  26. GRB 140606B: Fermi GBM detection
  27. GRB 140606A: BOOTES-2 optical upper limit
  28. Fermi423717114: iPTF optical transient candidates
  29. GRB 140606A: Nanshan optical upper limit
  30. GRB 140606A: Swift/UVOT Upper Limits
  31. GRB 140529A: Swift/UVOT Upper Limits
  32. Chandra late-time observations of GRB140515A
  33. Swift Trigger 600114: Optical spectroscopy from GTC
  34. GRB 140523A: NOT observation
  35. GRB 140523A: Nanshan optical upper limit
  36. GRB 140521A : Xinglong TNT upper limit
  37. GRB 140423A: TShAO optical observations
  38. GRB 140521A: AAO optical observations
  39. GRB 140521A: AROMA-N Optical Observation
  40. GRB 140521A: MITSuME Okayama upper limits
  41. GRB 140521A: MASTER optical observations
  42. GRB 140518A: T100 observations
  43. GRB 140518A: Continued RATIR Optical and NIR Observations
  44. GRB 140512A: MASTER prompt and afterglow optical observations
  45. GRB 140518A: Skynet GORT Detections of the Optical Afterglow
  46. GRB 140518A: Swift/UVOT Upper Limits
  47. GRB 140518A: RATIR Optical and NIR Observations
  48. GRB 140518A: Gemini-N redshift
  49. GRB 140518A: KAIT optical candidate
  50. GRB 140516A: RATIR Optical and NIR Observations
  51. GRB 140516A: Gemini-North limit on an optical afterglow
  52. GRB 140516A: Swift/UVOT Upper Limits
  53. GRB 140516A: NOT optical observations
  54. GRB 140516A: MASTER early optical observations
  55. GRB 140516A: ISON-Kislovodsk optical observations
  56. GRB 140516A: TNG optical observations
  57. GRB 140515A: VLA Detection
  58. GRB 140419A: Continued Mondy optical observations
  59. GRB 140515A: Optical observations from the 2.5 m NOT
  60. GRB 140515A: KAIT Optical Upper Limit
  61. GRB 140515A: Gemini-North imaging
  62. GRB 140515A: Swift/UVOT Upper Limits
  63. GRB 140423A: HCT optical observations
  64. GRB 140515A: MITSuME Akeno upper limits
  65. GRB 140423A: AAO optical upper limits
  66. GRB 140512A: Continued UVOT Observations
  67. GRB 140512A: Xinglong TNT optical observation
  68. GRB 140508A: Mondy upper limit
  69. GRB 140508A: MITSuME Akeno Optical observation
  70. GRB140512A : GROND observations
  71. GRB 140512A: Optical observations from the 2.5 m NOT
  72. GRB 140512A: Mondy optical detection
  73. GRB 140512A: Swift detection of a burst with an optical counterpart
  74. GRB 140512A: MASTER optical observations
  75. GRB 140423A: Mondy optical observations
  76. GRB 140508A: Continued RATIR Optical and NIR Observations
  77. GRB 140508A: ​HCT spectroscopy
  78. GRB 140508A: Swift/UVOT Detection
  79. GRB 140508A: RATIR Optical and NIR Observations
  80. GRB 140508A: Optical Observations via Virtual Telescope
  81. GRB 140508A: Swift-XRT observations
  82. GRB 140509A: Swift detection of a burst with an optical counterpart
  83. GRB 140508A: NOT photometry and spectroscopy
  84. GRB 140508A: SAO RAS and MASTER photometric and spectroscopic observations
  85. GRB 140508A: 1.23m CAHA BVRI-band observations
  86. GRB 140508A: iPTF optical transient candidate
  87. GRB 140430A: MITSuME Akeno upper limits
  88. GRB 140502A: ISON-NM early optical limit
  89. GRB 140506A: VLT/X-shooter spectroscopy
  90. GRB 140506A: Swift detection of a burst with an optical counterpart
  91. GRB 140430A: iTelescope.Net T16 Optical Observation
  92. GRB 140502A: MITSuME Okayama upper limits
  93. GRB 140430A: BVR-band IAC80 observations
  94. GRB 140430A: Further VATT Optical Observations
  95. GRB 140430A: VATT Optical Observations
  96. GRB 140430A: VLT/X-shooter redshift
  97. GRB 140430A: NOT optical observations
  98. GRB 140430A : Liverpool Telescope optical afterglow observations
  99. GRB140430A: Swift detection of a burst with an optical counterpart
  100. GRB 140428A: Swift/UVOT Upper Limits

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Looking for U.S. government information and services? Visit USA.gov