Skip to main content
New! Super-Kamiokande JSON Notices and Schema v4.5.0. 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"

20537 results found.

  1. GRB 050730: RTT150 optical observations
  2. GRB 050730: Swift XRT afterglow observations
  3. GRB 050730: PROMPT VRcIc Observations
  4. GRB050730, afterglow observations
  5. GRB050730: confirmation of redshift
  6. GRB 050730: Redshift Measurement based on Magellan/MIKE Observations
  7. GRB 050730, SMARTS optical/IR afterglow observations
  8. GRB050730: Liverpool Telescope optical observations
  9. GRB050730: Swift-BAT detection of a weak burst
  10. GRB 050709: PROMPT Rc Observations
  11. GRB050713b: Maidanak optical observations
  12. GRB 050724: Secure Host Redshift from Keck
  13. GRB 050724: WHT optical observations
  14. GRB050726: Swift UVOT observations
  15. GRB 050724: Chandra Observations of the X-ray Afterglow
  16. GRB050724: Refined Radio Position
  17. GRB 050724, SMARTS optical/IR afterglow observations
  18. GRB 050726, SMARTS optical/IR observations
  19. GRB 050727: RTT150 optical observations
  20. GRB050724: VLT observations of the variable source
  21. GRB 050726: PROMPT Rc Observations
  22. GRB 050724: dust-scattered X-ray halo detected in SWIFT/XRT observation
  23. GRB050724: Further Radio Observations
  24. GRB 050726: early Swift XRT analysis results
  25. GRB050726: Swift-BAT detection of a weak burst
  26. GRB 050724: Optical Variability in Nearby Galaxy
  27. GRB 050724: J-band observations
  28. GRB 050724: GMOS Imaging and Spectroscopy
  29. GRB050724: Radio Observation
  30. GRB 050724: spectroscopy of object in the XRT error circle
  31. GRB 050724: optical and near-IR observations
  32. GRB 050724: Optical imaging/astrometry
  33. GRB 050724: RTT150 optical observations
  34. GRB 050724 : Lulin early R-band monitoring observations
  35. GRB 050724: possible host galaxy in DSS
  36. GRB 050721: early afterglow light curve
  37. GRB 050721: optical afterglow confirmed
  38. GRB 050721a: Optical Observations
  39. GRB 050717: PROMPT RcIc Observations
  40. GRB050712: Radio Observations
  41. GRB 050712, Tautenburg optical afterglow observations
  42. Swift-BAT detection of a possible GRB
  43. GRB 050714B: VLT R-band observations
  44. GRB 050717: Additional LCO observations
  45. GRB 050716; J-band observations
  46. GRB 050717: LCO near-IR observations
  47. Swift/UVOT Observations of GRB 050717
  48. GRB 050717: Refined XRT analysis.
  49. Swift detection of GRB 050717
  50. GRB 050716 - UKIRT identification of candidate afterglow
  51. Swift UVOT Observations of GRB 050716
  52. GRB 050716: Refined XRT analysis.
  53. GRB 050716: Lulin B and R band optical observations
  54. GRB 050716: Optical Observations
  55. GRB050716: Faulkes North Telescope observation
  56. Swift/BAT detection of GRB 050716
  57. Swift UVOT Observations of GRB 050714B
  58. GRB 050714B: refined XRT analysis
  59. GRB 050713b: RTT150 optical observations
  60. Swift detection of a long transient (GRB 050714B?)
  61. GRB 050709: optical afterglow candidate
  62. GRB 050714, optical observations
  63. GRB 050709: Spectroscopy
  64. GRB050713B :Swift/UVOT observations
  65. GRB050712: TNG R-band observations
  66. GRB050712: Swift UVOT Observation of Afterglow Emission
  67. GRB 050713A : Lulin R-band observation
  68. GRB 050713b : Lulin R-band observations
  69. GRB050713B: Faulkes North Telescope observation
  70. RBO RI observations of GRB 050713A
  71. GRB 050713B
  72. GRB050713: Liverpool Telescope prompt observations
  73. GRB 050712, optical observations
  74. GRB050709: Candidate X-ray Afterglow from Chandra
  75. GRB 050713, R-band observations at NOT
  76. GRB 050713: ARC NIR Detections and Identification of Fading
  77. GRB 050713: Swift detection of Bright Burst
  78. GRB050709: Radio Observations
  79. GRB 050709: Swift UVOT and XRT observations
  80. GRB 050712: Swift detection of a weak burst
  81. GRB 050709: LCO40 Observations
  82. GRB050709, optical observations
  83. PROMPT Rc Observations of GRB 050709
  84. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  85. GRB 050525a: ARC 3.5-Meter SPIcam Field Calibration
  86. GRB 050626 optical observations
  87. GRB 050626: Swift XRT observations
  88. GRB 050701, optical observations
  89. GRB 050408: ARC 3.5-meter NIR Observations
  90. Swift UVOT observations of GRB 050701
  91. GRB 050607, radio observations
  92. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  93. GRB 050525A: Swift Late-Time Decay Rate
  94. GRB050525a: HST Observations
  95. CORRECTION: GRB050603 Swift UVOT Afterglow Observations
  96. H3800 and H3801 on 2005 June 11: two bursts from SGR1806-20 localized by HETE
  97. XRF 050509c: Optical monitoring
  98. XRF050509c: Radio Detection
  99. GRB 050416(a): Host Galaxy Redshift Determination
  100. GRB 050607: MDM Observation

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