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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"

32757 results found.

  1. NIR Observations of GRB 041219
  2. GRB041226: ROTSE-III Optical Observations
  3. GRB041223: decay of the afterglow
  4. GRB041224: ROTSE-III Optical Observations
  5. GRB 041224: near-infrared observations with REM
  6. GRB 041223: XRT afterglow spectrum and light curve
  7. GRB 041223 Fluence measured by Swift-BAT
  8. GRB041223: optical and NIR observations with REM
  9. Swift-BAT Time History of GRB041219
  10. GRB 041219: TAROT optical observations
  11. GRB 041223: J-band observations of the afterglow
  12. GRB 041223: Detection of Optical Transient with LCO40
  13. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  14. GRB 041219c: PROMPT Observations
  15. GRB041223: ROTSE-III Optical Observations
  16. GRB 041218: optical observations
  17. Very high activity of SGR 1806-20
  18. GRB 041219: Second Epoch WSRT Radio Observations
  19. GRB 041219: WSRT Radio Afterglow Detection
  20. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  21. GRB 041218: Optical observations
  22. GRB 041219 : optical follow-up observations
  23. Deep RAPTOR observations during GRB 041219
  24. GRB 041218 Optical Observations
  25. GRB 041219 Optical Observations
  26. GRB041219: Optical Afterglow Detection
  27. GRB041219: Continued NIR Observations
  28. GRB 041219: Radio Afterglow Detection
  29. GRB 041218 : Radio Observations
  30. GRB 041218: R-band optical observations
  31. GRB041218: Liverpool Telescope optical observations
  32. GRB041218: optical observations
  33. GRB041219: Confirmed NIR Afterglow
  34. Swift-BAT detection of the bright long burst GRB041219
  35. GRB 041218: Optical Observation
  36. GRB 041219: Infrared Afterglow Candidate
  37. GRB041219, BVRcIc field calibration
  38. GRB 041219: Infrared Afterglow Candidate
  39. GRB041218, BVRcIc field calibration
  40. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  41. GRB 041217: PROMPT Observations
  42. GRB041218: optical observations
  43. GRB041217: optical limit 30 min after GRB
  44. GRB 041218; optical candidate
  45. GRB 041218: Optical observations
  46. GRB 041217: LCO40 Optical Observations and Possible Candidates
  47. GRB041217: Optical Observations
  48. GRB041217: NIR and optical observations with REM
  49. GRB041217: Infrared Observations
  50. GRB041217: The First GRB Located On-Board Swift
  51. GRB041211: Faulkes Telescope continued optical monitoring
  52. Optical Transient in Lynx not a GRB
  53. Optical transient (GRB?) in Lynx
  54. GRB041211: Continued P60 Observations
  55. GRB041211, Faulkes Telescope optical observation
  56. GRB041211, BVRcIc field calibration
  57. GRB 041211: Infrared Observations
  58. GRB 041211: Optical follow-up in East Asian region
  59. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  60. GRB041015: Near-Infrared observations
  61. GRB 040924: Afterglow Color
  62. GRB 041006: GETS Optical Afterglow Observation
  63. Summary of the recent bursts from SGR 1806-20
  64. GRB 041006: Optical Observations
  65. GRB041006, late-time optical photometry
  66. GRB041006: RTT150 Optical Observations
  67. GRB041015 : Multi epoch optical observations
  68. GRB041006: RTT150 Optical Observations
  69. GRB 041016: Optical limits
  70. GRB 041015: Optical Observations at Rikubetsu
  71. GRB041006: Near Infrared observations
  72. GRB040924, BVRcIc field calibration
  73. GRB 041015: Optical limit at Osaka University
  74. GRB041015 : Optical follow-up at Kiso
  75. GRB 041006 R observations in Loiano
  76. GRB041006: VLT observations of the afterglow and host galaxy
  77. GRB041006: Optical observations and Potential host galaxy
  78. GRB041006, BVRcIc field calibration
  79. GRB 040924: VLT spectroscopy
  80. GRB 041006: SARA afterglow observations
  81. GRB041006, optical observation in CrAO
  82. Search for SN light in XRF 040912 with MEGACAM
  83. GRB 040916: Afterglow Color at Early Times
  84. GRB 041006 Optical afterglow observations
  85. GRB 041006: BR observations with VATT
  86. GRB 041006: Redshift confirmed
  87. GRB041006: Liverpool Telescope optical observations
  88. GRB 041006: Colour measurement
  89. GRB041006: break in the light curve
  90. GRB 041006: Radio Observations
  91. GRB 041006 : optical follow-up observation at Lulin Observatory
  92. GRB 041006 : Optical follow-up observation at TAROT
  93. GRB041006: Optical photometry and spectroscopy at TNG
  94. GRB 041006: presice astrometry
  95. GRB041006 (= H3570): Chandra Observations In Progress
  96. GRB 041006 : optical observation at Bisei
  97. GRB041006, optical I observation
  98. GRB041006 (=HETE3570): optical observations
  99. ROTSE-IIIa Observations of GRB 041006
  100. GRB041006, optical observation

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