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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"

41892 results found.

  1. GRB050802: TNG optical observations
  2. GRB050803: Radio Observation
  3. GRB 050803: RTT150 optical observations
  4. GRB050801: Radio Observation
  5. GRB050730: Radio Detection
  6. GRB050803: CrAO optical observations, possible OT candidate
  7. GRB050803: Optical/UV Upper Limits from Swift-UVOT
  8. GRB 050803: Keck Observations
  9. GRB 050803: Swift-BAT refined analysis
  10. GRB 050803, optical observations
  11. GRB 050803: Magellan Observations
  12. GRB 050803: early Swift XRT analysis results
  13. GRB 050803: TAROT optical limits
  14. GRB050803: MASTER optical observations
  15. GRB050802: Tentative absorption redshift
  16. GRB050803: Swift-BAT detection of a very long burst
  17. GCN GRB observation 050713A
  18. GRB050730: FORS1 and UVES/VLT low- and high-resolution spectroscopy
  19. GRB 050802: Swift/UVOT optical and UV detections
  20. GRB050802: CrAO optical observations
  21. GRB050801: Unchanged decay slope
  22. GRB050802 radio non-detection
  23. GRB 050730: OHP optical observations
  24. GRB 050802: early Swift XRT analysis results
  25. GRB 050802: Swift/UVOT observations
  26. GRB 050802 : Lulin Optical follow-up observation
  27. GRB050801: Optical photometry and decay index
  28. GRB 050802: XRT position
  29. GRB 050802: Swift Gamma-ray Burst
  30. GRB050801: Swift/UVOT Optical and UV detections
  31. GRB 050730: Preliminary Analysis of MIKE Spectrum
  32. GCN 050801: early Swift XRT analysis results
  33. GRB 050801, SMARTS optical/IR afterglow observations
  34. GRB 050801, afterglow observations
  35. GRB 050730, corrected photometry and break?
  36. GRB 050801: ROTSE-III Early Afterglow Break
  37. GRB050801: Swift-BAT detection of a burst
  38. GRB 050801: ROTSE-III Detection of Possible Counterpart
  39. GRB 050730: XRT refined analysis
  40. Correction to GCN Circ 3476 on GRB050525A
  41. GRB 050730: early TAROT optical observations
  42. GRB 050726: PROMPT Rc Observations
  43. GRB 050730: RTT150 optical observations
  44. Swift/UVOT photometry of GRB050730
  45. GRB 050730, spectra and optical photometry
  46. GRB050730: Refined BAT analysis of the Swift-BAT burst
  47. GRB 050730: Swift XRT afterglow observations
  48. GRB 050730: PROMPT VRcIc Observations
  49. GRB050730, afterglow observations
  50. GRB050730: confirmation of redshift
  51. GRB 050730: Redshift Measurement based on Magellan/MIKE Observations
  52. GRB 050730, SMARTS optical/IR afterglow observations
  53. GRB050730: Liverpool Telescope optical observations
  54. GRB 050730, optical candidate
  55. GRB050730: Swift-BAT detection of a weak burst
  56. GRB 050713A: Swift XRT extended light curve
  57. GRB 050709: PROMPT Rc Observations
  58. GRB050713b: Maidanak optical observations
  59. GRB 050724: WHT optical observations
  60. GRB050726: Swift UVOT observations
  61. GRB 050724: Chandra Observations of the X-ray Afterglow
  62. GRB050724: Refined Radio Position
  63. GRB050713: analysis of the XMM-Newton observation
  64. GRB 050724, SMARTS optical/IR afterglow observations
  65. GRB 050726, SMARTS optical/IR observations
  66. Swift-BAT trigger 147918 is not a real GRB
  67. GRB 050727: RTT150 optical observations
  68. GRB050724: VLT observations of the variable source
  69. GRB050727: KAIT optical limit
  70. GRB050709: Second Epoch Chandra Observation
  71. GRB 050726: PROMPT Rc Observations
  72. GRB050709: Second Epoch Chandra Observation
  73. GRB 050724: dust-scattered X-ray halo detected in SWIFT/XRT observation
  74. GRB050724: Further Radio Observations
  75. GRB 050726: early Swift XRT analysis results
  76. GRB050726: Swift-BAT detection of a weak burst
  77. GRB 050724: Optical Variability in Nearby Galaxy
  78. GRB 050724: J-band observations
  79. GRB 050724: GMOS Imaging and Spectroscopy
  80. GRB 050724: SWIFT XRT refined position
  81. RXTE ASM Detection of GRB050724
  82. GRB050724: Radio Observation
  83. GRB 050724: spectroscopy of object in the XRT error circle
  84. GRB 050724: optical and near-IR observations
  85. GRB 050724: Optical imaging/astrometry
  86. GRB 050724: RTT150 optical observations
  87. GRB 050724: Swift/UVOT Upper Limit
  88. GRB 050724: early Swift XRT analysis results
  89. GRB 050724 : Lulin early R-band monitoring observations
  90. GRB050724: Refined analysis of the Swift-BAT possible short burst
  91. GRB 050724: possible host galaxy in DSS
  92. GRB050724: a short-burst detected by Swift
  93. GRB050723: XRT distributed coordinates are not related to the burst
  94. GRB 050721: early afterglow light curve
  95. GRB 050721A: Swift-BAT refined analysis
  96. GRB 050721A: Early Swift XRT analysis results
  97. GRB050721A: optical decay
  98. GRB 050721: optical afterglow confirmed
  99. Swift BAT Trigger 146986 is SWIFT J1753.5-0127
  100. GRB 050721a: Optical Observations

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