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"

20994 results found.

  1. GRB 070412: further NOT observations
  2. GRB 070412: IAC80 optical afterglow candidate
  3. GRB 070411: Magellan/Clay photometry
  4. GRB 070411: Magellan/IMACS photometry
  5. GRB 070412: NOT observations
  6. GRB 070411: IAC80 optical observations
  7. GRB 070411 : Liverpool Telescope Observations
  8. GRB 070411: Optical observations at Crni Vrh
  9. GRB 070411: ROTSE-III Detection of Optical Counterpart
  10. GRB 070411: Tautenburg RRM Afterglow Confirmation
  11. GRB 070406: "Star" in XRT error circle S2 is an AGN?
  12. GRB 070406: Swift XRT team further analysis
  13. GRB 070406: Bright galaxy in XRT error circle is a quasar
  14. GRB 070406: Gemini South Imaging and XRT analysis
  15. GRB070406: Swift UVOT observations
  16. Short GRB 070406 - Possible Bright Host Galaxy
  17. GRB 070406: Swift XRT Team analysis - Possible X-ray counterpart
  18. GRB 070406: NOT observations
  19. GRB 070311, deep optical photometry
  20. Konus-Wind and Konus-A observations of GRB 070402
  21. INTEGRAL ToO Observation of SGR1806-20
  22. UVOT observations of GRB070330
  23. GRB 070330, SMARTS optical/IR observations
  24. GRB 070330: TAROT La Silla observatory optical observations
  25. GRB 070330 - Watcher Observations
  26. GRB070220: optical observations
  27. GRB070208: optical observations
  28. GRB070223: confirmation of nIR and optical afterglow
  29. GRB070318: Swift UVOT indicates unusual optical/UV afterglow
  30. GRB 070311, deep optical photometry
  31. Short-Hard GRB 070209: PROMPT Observations
  32. GRB 070318: Gemini + Magellan spectra
  33. GRB 070318: absorption-line redshift
  34. GRB070318: Swift UVOT continuing observations
  35. GRB 070318: Swift/UVOT Continued Observations
  36. GRB 070311: MDM Optical Monitoring
  37. GRB 070311: Tautenburg sees afterglow fading
  38. GRB 070311: Optical Brightening
  39. GRB 070306: possible emission-line redshift
  40. GRB 070311: SARA upper limit
  41. GRB 070309: variability of the XRT afterglow candidate
  42. GRB 070311: P60 Observations
  43. GRB 070311: MDM Optical Detection
  44. GRB 070311: REM candidate afterglow
  45. GRB060901: Candidate optical afterglow
  46. GRB070309: Swift/XRT possible afterglow detection
  47. GRB 070125: Chandra X-ray Confirmation of Jet Break
  48. GRB 070125: X-ray light curve analysis
  49. GRB 070306: NOT observations
  50. GRB070306: confirmation of near infrared afterglow
  51. GRB 070306: IR observations and candidate afterglow
  52. GRB 070306: Optical and IR observations with KANATA
  53. GRB070306 - SDSS Pre-burst Observations
  54. GRB 070223: NIR observations at WHT
  55. GRB070227: Swift-XRT refined analysis
  56. GRB 070227: optical observations
  57. GRB 070223: Optical Observations
  58. GRB 070227: optical observations
  59. GRB 070227: Swift/UVOT Upper Limits
  60. GRB 070227: TAROT La Silla observatory optical observations
  61. GRB070227: possible X-ray afterglow detection
  62. GRB 920925C: optical afterglow candidate
  63. GRB 070224: Swift/UVOT Upper Limits
  64. GRB070224: Magellan Imaging Observations
  65. GRB 070224: MDM Observations
  66. GRB070224: Gemini Imaging Observations
  67. GRB 070224: SARA upper limit
  68. GRB 070224: optical afterglow candidate
  69. GRB 070224: MASTER-VWF-Kislovodsk observations
  70. GRB 070224: MASTER observations
  71. GRB 070223: Optical observations
  72. GRB070223: Swift/UVOT refined analysis
  73. GRB070223: MASTER-VWF-Kislovodsk observations
  74. GRB070223 - SDSS Pre-Burst Observations
  75. GRB 070223: Liverpool Telescope Possible Afterglow Candidate
  76. GRB 070223: MDM Observations
  77. Konus-Wind and Konus-A observations of GRB 070220
  78. Swift/UVOT refined analysis of GRB070220
  79. GRB 070219: Gemini Observations
  80. GRB 070220 : Faulkes Telescope North optical limit
  81. GRB070219: MASTER-VWF-Kislovodsk observations
  82. GRB 070219: Swift/UVOT Upper limits
  83. GRB 070219: I-band observations
  84. GRB 070219: optical TNG observations
  85. GRB 070219: Liverpool Telescope Observations
  86. GRB070219 - SDSS Pre-Burst Observations
  87. GRB 070125 observations with the GMRT
  88. GRB 060927: PROMPT Observations
  89. GRB 070125: Break in Optical Decay
  90. GRB070208: optical observations
  91. GRB 070208: MARGE Optical Observations
  92. GRB070208 - SDSS Pre-Burst Observations
  93. GRB070208: Faulkes Telescope North Afterglow Identification
  94. GRB 070208: MDM Observations
  95. GRB 070125: Redshift z>~1.54 from Gemini Afterglow Spectrum
  96. GRB 070129: afterglow confirmation
  97. GRB 070125: further AAVSO optical observations
  98. GRB 070129: Swift/UVOT Upper limits
  99. GRB 070125: optical observation
  100. GRB 070125: WSRT Radio Detection

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