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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"

33873 results found.

  1. GRB 050813: I-band observations
  2. GRB050813, SDSS pre-burst observations
  3. GRB 050813: KAIT optical limit
  4. GRB 050813: Swift-BAT refined analysis
  5. GRB 050813: Photometry of object in XRT error circle
  6. GRB 050813: Swift XRT afterglow localization
  7. RBO GRB 050714A and GRB 050716 observations
  8. GRB 050813: Possible Short Swift-BAT GRB
  9. Swift-BAT trigger 150131 is not a GRB
  10. GRB050807(=H3889): An X-Ray Rich GRB Localized by HETE
  11. Ongoing activity of SGR 1806-20: an intermediate burst 050811
  12. GRB050803: CrAO optical observations, no OT candidate
  13. GRB 050730: WSRT Radio Observations
  14. GRB 050803: PROMPT BVRcIc Observations
  15. GRB 050807: ROTSE-III Optical Limits
  16. GRB 050730, optical observation
  17. GRB050805b: CrAO optical limit
  18. GRB050805a : Null detection report
  19. GRB050730, optical observations
  20. GRB050803, optical observations
  21. Swift-BAT trigger 149118 is very likely not a GRB
  22. Retraction of Swift Trigger 149131 (GRB 050805B)
  23. GRB 050805b: OHP optical limits
  24. GRB 050805b: TAROT optical limits
  25. GRB050805b: MASTER optical observations
  26. Possible GRB 050805B: Swift-BAT trigger 149131 may be a burst
  27. GRB050805a: MASTER optical candidat
  28. Swift-BAT trigger 149118 is probably not a GRB
  29. GRB 050803: RTT150 optical observations
  30. GRB050803: CrAO optical observations, possible OT candidate
  31. GRB 050803: Keck Observations
  32. GRB 050803: Swift-BAT refined analysis
  33. GRB 050802.422: Fading of the afterglow and detection of the host
  34. GRB050803: MASTER further analys
  35. GRB 050803, optical observations
  36. GRB 050803: Magellan Observations
  37. GRB 050803: early Swift XRT analysis results
  38. GRB 050803: TAROT optical limits
  39. GRB050803: MASTER optical observations
  40. GRB050802: Tentative absorption redshift
  41. GCN GRB observation 050713A
  42. GRB050730: FORS1 and UVES/VLT low- and high-resolution spectroscopy
  43. GRB 050802: Swift/UVOT optical and UV detections
  44. GRB050802: CrAO optical observations
  45. GRB050801: Unchanged decay slope
  46. GRB 050730: OHP optical observations
  47. GRB 050802: early Swift XRT analysis results
  48. GRB 050802: Swift/UVOT observations
  49. GRB 050802 : Lulin Optical follow-up observation
  50. GRB 050802: Swift-BAT refined analysis
  51. GRB050801: Optical photometry and decay index
  52. GRB 050802: XRT position
  53. GRB 050802: Swift Gamma-ray Burst
  54. GRB 050730: Preliminary Analysis of MIKE Spectrum
  55. GCN 050801: early Swift XRT analysis results
  56. GRB 050801: Swift-BAT refined analysis
  57. GRB 050801, SMARTS optical/IR afterglow observations
  58. GRB 050801, afterglow observations
  59. GRB 050730, corrected photometry and break?
  60. GRB 050801: ROTSE-III Early Afterglow Break
  61. GRB050801: Swift-BAT detection of a burst
  62. GRB 050801: ROTSE-III Detection of Possible Counterpart
  63. GRB 050730: XRT refined analysis
  64. Correction to GCN Circ 3476 on GRB050525A
  65. GRB 050730: early TAROT optical observations
  66. GRB 050726: PROMPT Rc Observations
  67. GRB 050730: RTT150 optical observations
  68. GRB 050730, spectra and optical photometry
  69. GRB050730: Refined BAT analysis of the Swift-BAT burst
  70. GRB 050730: Swift XRT afterglow observations
  71. GRB 050730 XMM-Newton observation
  72. GRB 050730: PROMPT VRcIc Observations
  73. GRB050730, afterglow observations
  74. GRB050730: confirmation of redshift
  75. GRB 050730: Redshift Measurement based on Magellan/MIKE Observations
  76. GRB 050730, SMARTS optical/IR afterglow observations
  77. GRB 050730 : Planned XMM-Newton observation
  78. GRB050730: Liverpool Telescope optical observations
  79. GRB 050730, optical candidate
  80. GRB050730: Swift-BAT detection of a weak burst
  81. GRB 050713A: Swift XRT extended light curve
  82. GRB 050709: PROMPT Rc Observations
  83. GRB050713b: Maidanak optical observations
  84. GRB 050724: Secure Host Redshift from Keck
  85. GRB 050724: WHT optical observations
  86. GRB 050724: Chandra Observations of the X-ray Afterglow
  87. GRB050713: analysis of the XMM-Newton observation
  88. GRB 050724, SMARTS optical/IR afterglow observations
  89. GRB 050726, SMARTS optical/IR observations
  90. Swift-BAT trigger 147918 is not a real GRB
  91. GRB 050727: RTT150 optical observations
  92. GRB050724: VLT observations of the variable source
  93. GRB050727: KAIT optical limit
  94. GRB050709: Second Epoch Chandra Observation
  95. GRB 050726: PROMPT Rc Observations
  96. GRB050709: Second Epoch Chandra Observation
  97. GRB 050724: dust-scattered X-ray halo detected in SWIFT/XRT observation
  98. GRB 050726: early Swift XRT analysis results
  99. GRB 050724: Optical Variability in Nearby Galaxy
  100. GRB 050724: J-band observations

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