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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"

36350 results found.

  1. GRB 050807: ROTSE-III Optical Limits
  2. GRB 050730, optical observation
  3. GRB050805b: CrAO optical limit
  4. GRB050805a : Null detection report
  5. GRB050730, optical observations
  6. GRB050803, optical observations
  7. Swift-BAT trigger 149118 is very likely not a GRB
  8. Retraction of Swift Trigger 149131 (GRB 050805B)
  9. GRB 050805b: OHP optical limits
  10. GRB 050805b: TAROT optical limits
  11. GRB050805b: MASTER optical observations
  12. Possible GRB 050805B: Swift-BAT trigger 149131 may be a burst
  13. GRB050805a: MASTER optical candidat
  14. Swift-BAT trigger 149118 is probably not a GRB
  15. GRB 050803: RTT150 optical observations
  16. GRB050803: CrAO optical observations, possible OT candidate
  17. GRB 050803: Keck Observations
  18. GRB 050803: Swift-BAT refined analysis
  19. GRB 050802.422: Fading of the afterglow and detection of the host
  20. GRB050803: MASTER further analys
  21. GRB 050803, optical observations
  22. GRB 050803: Magellan Observations
  23. GRB 050803: early Swift XRT analysis results
  24. GRB 050803: TAROT optical limits
  25. GRB050803: MASTER optical observations
  26. GRB050802: Tentative absorption redshift
  27. GCN GRB observation 050713A
  28. GRB050730: FORS1 and UVES/VLT low- and high-resolution spectroscopy
  29. GRB 050802: Swift/UVOT optical and UV detections
  30. GRB050802: CrAO optical observations
  31. GRB050801: Unchanged decay slope
  32. GRB 050730: OHP optical observations
  33. GRB 050802: early Swift XRT analysis results
  34. GRB 050802: Swift/UVOT observations
  35. GRB 050802 : Lulin Optical follow-up observation
  36. GRB 050802: Swift-BAT refined analysis
  37. GRB050801: Optical photometry and decay index
  38. GRB 050802: XRT position
  39. GRB 050802: Swift Gamma-ray Burst
  40. GRB 050730: Preliminary Analysis of MIKE Spectrum
  41. GCN 050801: early Swift XRT analysis results
  42. GRB 050801: Swift-BAT refined analysis
  43. GRB 050801, SMARTS optical/IR afterglow observations
  44. GRB 050801, afterglow observations
  45. GRB 050730, corrected photometry and break?
  46. GRB 050801: ROTSE-III Early Afterglow Break
  47. GRB050801: Swift-BAT detection of a burst
  48. GRB 050801: ROTSE-III Detection of Possible Counterpart
  49. GRB 050730: XRT refined analysis
  50. Correction to GCN Circ 3476 on GRB050525A
  51. GRB 050730: early TAROT optical observations
  52. GRB 050726: PROMPT Rc Observations
  53. GRB 050730: RTT150 optical observations
  54. GRB 050730, spectra and optical photometry
  55. GRB050730: Refined BAT analysis of the Swift-BAT burst
  56. GRB 050730: Swift XRT afterglow observations
  57. GRB 050730 XMM-Newton observation
  58. GRB 050730: PROMPT VRcIc Observations
  59. GRB050730, afterglow observations
  60. GRB050730: confirmation of redshift
  61. GRB 050730: Redshift Measurement based on Magellan/MIKE Observations
  62. GRB 050730, SMARTS optical/IR afterglow observations
  63. GRB 050730 : Planned XMM-Newton observation
  64. GRB050730: Liverpool Telescope optical observations
  65. GRB 050730, optical candidate
  66. GRB050730: Swift-BAT detection of a weak burst
  67. GRB 050713A: Swift XRT extended light curve
  68. GRB 050709: PROMPT Rc Observations
  69. GRB050713b: Maidanak optical observations
  70. GRB 050724: Secure Host Redshift from Keck
  71. GRB 050724: WHT optical observations
  72. GRB 050724: Chandra Observations of the X-ray Afterglow
  73. GRB050713: analysis of the XMM-Newton observation
  74. GRB 050724, SMARTS optical/IR afterglow observations
  75. GRB 050726, SMARTS optical/IR observations
  76. Swift-BAT trigger 147918 is not a real GRB
  77. GRB 050727: RTT150 optical observations
  78. GRB050727: KAIT optical limit
  79. GRB050709: Second Epoch Chandra Observation
  80. GRB 050726: PROMPT Rc Observations
  81. GRB050709: Second Epoch Chandra Observation
  82. GRB 050724: dust-scattered X-ray halo detected in SWIFT/XRT observation
  83. GRB 050726: early Swift XRT analysis results
  84. GRB 050724: Optical Variability in Nearby Galaxy
  85. GRB 050724: J-band observations
  86. GRB 050724: GMOS Imaging and Spectroscopy
  87. GRB 050724: SWIFT XRT refined position
  88. GRB 050724: spectroscopy of object in the XRT error circle
  89. GRB 050724: Optical limit
  90. GRB 050724: optical and near-IR observations
  91. GRB 050724: Optical imaging/astrometry
  92. GRB 050724: RTT150 optical observations
  93. GRB 050724: Swift/UVOT Upper Limit
  94. GRB 050724: early Swift XRT analysis results
  95. GRB 050724 : Lulin early R-band monitoring observations
  96. GRB050724: Refined analysis of the Swift-BAT possible short burst
  97. GRB 050724: possible host galaxy in DSS
  98. Swift-BAT trigger 147325 is not due to a real GRB
  99. GRB050723: XRT distributed coordinates are not related to the burst
  100. GRB 050721: early afterglow light curve

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