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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"

36236 results found.

  1. GRB 041218: optical observations
  2. GRB 041219: Second Epoch WSRT Radio Observations
  3. GRB 041219: WSRT Radio Afterglow Detection
  4. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  5. GRB 041218: Optical observations
  6. GRB 041219 : optical follow-up observations
  7. Deep RAPTOR observations during GRB 041219
  8. GRB 041218 Optical Observations
  9. GRB 041219 Optical Observations
  10. GRB041219c: Third Burst in One Day from Swift-BAT
  11. GRB041219: Optical Afterglow Detection
  12. GRB041219: Continued NIR Observations
  13. GRB 041219 ,optical observation
  14. GRB 041219: Radio Afterglow Detection
  15. GRB 041218 : Radio Observations
  16. GRB 041218: R-band optical observations
  17. GRB041219: Confirmed NIR Afterglow
  18. GRB041218: Continued P60 Optical Observations
  19. GRB 041218: Optical Observation
  20. GRB 041219: Infrared Afterglow Candidate
  21. GRB041219, BVRcIc field calibration
  22. GRB 041219: Infrared Afterglow Candidate
  23. GRB041218, BVRcIc field calibration
  24. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  25. GRB041219: P60 Optical Observations
  26. GRB 041219 - A long GRB detected by INTEGRAL
  27. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  28. GRB 041217: PROMPT Observations
  29. GRB041218: optical observations
  30. GRB041217: optical limit 30 min after GRB
  31. GRB 041218; optical candidate
  32. GRB 041218: Optical observations
  33. GRB 041217: LCO40 Optical Observations and Possible Candidates
  34. GRB 041218 - A long GRB detected by integral
  35. GRB041217: Optical Observations
  36. GRB041217: P60 Optical Observations
  37. GRB041217: Infrared Observations
  38. GRB041217: The First GRB Located On-Board Swift
  39. GRB041211: Faulkes Telescope continued optical monitoring
  40. Optical Transient in Lynx not a GRB
  41. Optical transient (GRB?) in Lynx
  42. Optical transient (GRB?) in Lynx, UT Dec 11.4436
  43. GRB041211: Continued P60 Observations
  44. GRB041211: RAPTOR observations
  45. GRB041211: Ashra Prototype optical observation
  46. GRB041211, Faulkes Telescope optical observation
  47. GRB041211, BVRcIc field calibration
  48. GRB 041211: Infrared Observations
  49. GRB 041211: KAIT observations
  50. GRB 041211: Optical follow-up in East Asian region
  51. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  52. GRB041211: P60 optical imaging
  53. GRB970815: Discovery of Optical Afterglow
  54. Distribution of IBAS Alerts for NON-GRB sources
  55. Triangulation of short GRB 041116 (large error box)
  56. GRB 040924: Afterglow Color
  57. GRB 041006: GETS Optical Afterglow Observation
  58. Summary of the recent bursts from SGR 1806-20
  59. GRB 041006: Optical Observations
  60. GRB041006, late-time optical photometry
  61. IBAS GRB Alert # 2034
  62. GRB041006: RTT150 Optical Observations
  63. Bright bursts from SGR1806-20
  64. GRB 041016: BOOTES-2 simultaneous observation
  65. GRB041006: RTT150 Optical Observations
  66. GRB 041016: Optical limits
  67. GRB 041016: Optical limits in V, R, I
  68. GRB 041016:Optical limit during first minute
  69. GRB041016: MASTER: Optical observations
  70. GRB 041015: Optical Observations at Rikubetsu
  71. GRB041006: Near Infrared observations
  72. GRB 041016: Optical limit
  73. GRB 041015 R band observations
  74. GRB040924, BVRcIc field calibration
  75. GRB041015: MASTER: Optical observations
  76. GRB041015,optical observation
  77. GRB 041015: Optical limit at Osaka University
  78. GRB041015 : Optical follow-up at Kiso
  79. GRB 041015 - A long GRB detected by INTEGRAL
  80. GRB 041006 R observations in Loiano
  81. GRB041006: VLT observations of the afterglow and host galaxy
  82. GRB041006: Optical observations and Potential host galaxy
  83. GRB041006, BVRcIc field calibration
  84. GRB 040924: VLT spectroscopy
  85. GRB 041006: SARA afterglow observations
  86. Search for SN light in XRF 040912 with MEGACAM
  87. GRB 040916: Afterglow Color at Early Times
  88. GRB 041006 Optical afterglow observations
  89. IBAS GRB Alert # 2010
  90. GRB 041006: BR observations with VATT
  91. GRB 041006: Redshift confirmed
  92. GRB041006: Liverpool Telescope optical observations
  93. GRB 041006: Colour measurement
  94. GRB041006: break in the light curve
  95. GRB 041006: Radio Observations
  96. GRB041006, further submilllimetre observations
  97. GRB 041006 : optical follow-up observation at Lulin Observatory
  98. GRB 041006 : Optical follow-up observation at TAROT
  99. GRB041006: Optical photometry and spectroscopy at TNG
  100. GRB 041006: presice astrometry

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