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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"

28125 results found.

  1. GRB050117: Swift XRT Position
  2. SGR 1806-20: Further low frequency GMRT results
  3. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  4. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  5. SGR 1806-20: Temporal and Spectral behavior of radio transient
  6. Second-epoch VLA observations of SGR 1806-20
  7. SGR1806: Detection of a Sudden Ionospheric Disturbance
  8. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  9. SGR1806 VLA Observations
  10. GRB 041217: Optical observations
  11. SGR1806-20: Swift-BAT observation of the 041227 super-flare
  12. GRB041219, early time observations
  13. Detection of the SGR 1806-20 giant outburst back-scattered by the
  14. GRB041228: Swift-BAT detection of a burst
  15. GRB041219; RXTE ASM Observations
  16. NIR Observations of GRB 041219
  17. GRB041226: Swift-BAT detection of a burst
  18. GRB041223: decay of the afterglow
  19. GRB 041223: XRT afterglow spectrum and light curve
  20. GRB041224: Swift-BAT detection of a soft burst
  21. GRB041223: optical and NIR observations with REM
  22. Swift-BAT Time History of GRB041219
  23. GRB 041223: J-band observations of the afterglow
  24. GRB 041223: Detection of Optical Transient with LCO40
  25. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  26. GRB041223: Swift-BAT detection of a bright long burst
  27. GRB 041218: optical observations
  28. GRB 041219: WSRT Radio Afterglow Detection
  29. GRB 041218: Optical observations
  30. GRB 041219 : optical follow-up observations
  31. GRB 041219 Optical Observations
  32. GRB041219: Optical Afterglow Detection
  33. GRB041219: Continued NIR Observations
  34. GRB041219b: A Swift-BAT burst
  35. GRB 041219: Radio Afterglow Detection
  36. GRB 041218 : Radio Observations
  37. GRB 041218: R-band optical observations
  38. GRB041218: Liverpool Telescope optical observations
  39. GRB041218: optical observations
  40. GRB041219: Confirmed NIR Afterglow
  41. GRB041218: Continued P60 Optical Observations
  42. Swift-BAT detection of the bright long burst GRB041219
  43. GRB 041219: Infrared Afterglow Candidate
  44. GRB 041219: Infrared Afterglow Candidate
  45. GRB041218, BVRcIc field calibration
  46. GRB041218: optical observations
  47. GRB 041218: Optical observations
  48. GRB 041217: LCO40 Optical Observations and Possible Candidates
  49. GRB041217: Infrared Observations
  50. Optical transient (GRB?) in Lynx
  51. GRB041211, BVRcIc field calibration
  52. GRB041211: P60 optical imaging
  53. GRB970815: Discovery of Optical Afterglow
  54. Distribution of IBAS Alerts for NON-GRB sources
  55. GRB 040924: Afterglow Color
  56. GRB 041006: GETS Optical Afterglow Observation
  57. GRB 041006: Optical Observations
  58. GRB041006, late-time optical photometry
  59. GRB041006: RTT150 Optical Observations
  60. HST Observations: XRF 040701 and 040812
  61. GRB041006: RTT150 Optical Observations
  62. GRB 041016: Optical limits
  63. GRB041006: Near Infrared observations
  64. GRB040924, BVRcIc field calibration
  65. GRB041006: Fading X-ray Afterglow Observed with Chandra
  66. GRB041006: VLT observations of the afterglow and host galaxy
  67. GRB041006: Optical observations and Potential host galaxy
  68. GRB041006, BVRcIc field calibration
  69. GRB 041006: SARA afterglow observations
  70. Search for SN light in XRF 040912 with MEGACAM
  71. GRB 040916: Afterglow Color at Early Times
  72. GRB 041006 Optical afterglow observations
  73. GRB 041006: BR observations with VATT
  74. GRB 041006: Redshift confirmed
  75. GRB041006: Liverpool Telescope optical observations
  76. GRB 041006: Colour measurement
  77. GRB041006: break in the light curve
  78. GRB 041006: Radio Observations
  79. GRB041006, further submilllimetre observations
  80. GRB 041006 : optical follow-up observation at Lulin Observatory
  81. GRB 041006 : Optical follow-up observation at TAROT
  82. GRB041006: Optical photometry and spectroscopy at TNG
  83. GRB041006 (= H3570): Chandra Observations In Progress
  84. GRB 041006 : optical observation at Bisei
  85. GRB041006, optical I observation
  86. GRB041006, submillimetre observations
  87. GRB 041006: Optical decay
  88. GRB041006: Fading of optical afterglow candidate
  89. GRB 041006: Finding chart
  90. GRB 041006: Optical afterglow candidate
  91. GRB 040924: Second Epoch WSRT Radio Observations
  92. radio observations, GRB 040924
  93. GRB040924,optical observation
  94. GRB040924, RTT150 optical observation
  95. GRB 040924: detection of possible host galaxy by Subaru
  96. GRB040924, RTT150 optical observation
  97. GRB040924: Afterglow magnitude at t=17.5hr
  98. GRB 040924: WSRT Radio Observations
  99. GRB 040924: Subaru NIR observation
  100. GRB040924: Optical afterglow properties

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