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"

35987 results found.

  1. GRB 050319: NIR afterglow candidate
  2. GRB 050319:Near IR afterglow
  3. GRB 050318: SWIFT-UVOT refined analysis
  4. GRB 050318: Absorption redshift from Magellan
  5. GRB 050319: Optical observation
  6. GRB 050319 : Confirmation of optical afterglow decay
  7. GRB 050319: Swift-BAT refined analysis
  8. GRB050319,optical observation
  9. Swift Detection of GRB 050319
  10. GRB 050319: Detection of Possible Optical Counterpart
  11. GRB 050318: Swift/UVOT detection of afterglow emission
  12. GRB 050318: Magellan optical afterglow identification
  13. GRB050318: Swift XRT position
  14. RXTE Observations of GRB050318
  15. Swift-BAT detection of GRB 050318
  16. GRB 050315, SMARTS optical afterglow decay
  17. GRB050316: MASTER before, simultanious and follow up optical
  18. GRB 050306: ROTSE-III early limits
  19. GRB050316: MASTER optical observations
  20. GRB 050315: Swift-BAT further refined analysis
  21. GRB 050315, SMARTS optical/IR afterglow observations
  22. GRB 050315 I-band observations
  23. GRB050315: Radio afterglow
  24. GRB 050315: Absorption redshift
  25. GRB 050315: Optical afterglow identification
  26. GRB050315: Swift-BAT Refined analysis
  27. Non-detection of GRB050315 in ATCA Radio Observations
  28. GRB 050315: Swift XRT Position
  29. GRB 050219b: Gemini/GNIRS near-infrared spectroscopy
  30. GRB 050315: Early Observations with Swift/UVOT
  31. Swift-BAT detection of GRB 050315
  32. GRB 050306: Radio Observations
  33. GRB050306: 250 GHz upper limit with MAMBO at the IRAM 30m
  34. GRB050309: CONCAM pre-trigger and trigger coincident optical
  35. GRB 050306: optical afterglow
  36. GRB 050126: Redshift determination
  37. Swift-BAT trigger 107873: No Swift XRT counterpart
  38. GRB 050306: Confirmation of X-ray afterglow
  39. GRB 050309, Early optical limits from RAPTOR
  40. GRB 050306: further TAROT optical data
  41. GRB050309: Early optical limit from P60
  42. Swift-BAT trigger 107873 (GRB050309): possible X-ray counterparts
  43. GRB 050309 : Lulin R-band observation
  44. Swift 107873: P60 Optical Observations
  45. GRB 050306: CORRECTION to date of observation
  46. GRB 050306: R-band observations
  47. GRB 050306: No Swift UVOT Optical Counterpart Detected
  48. GRB 050306: REM optical-infrared observations
  49. GRB 050306: Possible X-ray Afterglow Position from the Swift
  50. Swift trigger 107518: optical observation
  51. GRB 050306: TAROT optical observations
  52. GRB 050306,optical observation
  53. GRB 050306: Swift-BAT detection of a long burst
  54. GRB 050126: Confirmation of the NIR afterglow candidate
  55. PROMPT VRcIc Observations of GRB 050223
  56. XRF/GRB 050215B: Radio Observations
  57. XMM-Newton Images of GRB 050223
  58. GRB 050219b: candidate NIR afterglow
  59. IBAS GRB Alert #2321
  60. GRB 050223: optical observations
  61. INTEGRAL detection of GRB 050223
  62. GRB 050223 : Planned XMM-Newton observation
  63. GRB050223: ROTSE-III Optical Observations
  64. GRB 050223 Swift/BAT detection of a burst
  65. GRB 050223: Swift XRT Position
  66. HETE-2 Observations of GRB 050215b (=U11570): A Likely X-Ray Flash
  67. GRB 050219b: CORRECTION to refined XRT position
  68. GRB 050219a: Optical observations from LCO
  69. GRB 050219b: Optical and near-IR observations from LCO
  70. GRB 050219b: Refined XRT position
  71. GRB 050219b: Swift-BAT detection of a burst
  72. GRB 050219b: CORRECTION: Swift XRT Position
  73. GRB 050219b: Swift XRT Position
  74. GRB 050219a, optical observations
  75. GRB 050219a: Refined XRT position
  76. GRB 050219: Swift-BAT detection of a burst
  77. GRB050215b: Swift UVOT Detection of Afterglow Emission
  78. GRB 050219: Prompt X-ray position
  79. GRB 050215B: Radio Observations
  80. GRB 050215b: XRT confirmation of IR afterglow candidate
  81. GRB050215b: P60 Optical Observations
  82. GRB 050215b: Swift XRT Source Variability
  83. GRB 050215B: candidate afterglow
  84. GRB 050215b : Lulin follow-up observation
  85. GRB 050215b, BOOTES-2 simultaneous optical observations
  86. GRB 050215B: UKIRT K-band imaging
  87. GRB 050215b: Swift XRT Observations
  88. GRB 050215b, BOOTES-1B optical limit
  89. GRB050215A: ROTSE-III Optical Observations
  90. GRB050209: TAROT optical observations
  91. GRB 050209(=U11568): Duration and spectrum
  92. short/hard GRB 050202, optical observations
  93. GRB050209: REM optical observations
  94. GRB 050209 I-band observation
  95. GRB 050209 Optical observations
  96. GRB050209: P60 Optical Observations
  97. GRB050209 (=U11568): A Long GRB Detected by HETE
  98. GRB 050209: Optical observation
  99. GRB 050128: Radio observations
  100. Further analysis of the short Swift-BAT GRB 050202

Advanced

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