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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"

32548 results found.

  1. GRB 041219: TAROT optical observations
  2. GRB 041223: J-band observations of the afterglow
  3. GRB 041223: Detection of Optical Transient with LCO40
  4. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  5. GRB 041219c: PROMPT Observations
  6. GRB041223: ROTSE-III Optical Observations
  7. GRB 041218: optical observations
  8. Very high activity of SGR 1806-20
  9. GRB 041219: Second Epoch WSRT Radio Observations
  10. GRB 041219: WSRT Radio Afterglow Detection
  11. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  12. GRB 041218: Optical observations
  13. GRB 041219 : optical follow-up observations
  14. Deep RAPTOR observations during GRB 041219
  15. GRB 041218 Optical Observations
  16. GRB 041219 Optical Observations
  17. GRB041219: Optical Afterglow Detection
  18. GRB041219: Continued NIR Observations
  19. GRB 041219: Radio Afterglow Detection
  20. GRB 041218 : Radio Observations
  21. GRB 041218: R-band optical observations
  22. GRB041218: Liverpool Telescope optical observations
  23. GRB041218: optical observations
  24. GRB041219: Confirmed NIR Afterglow
  25. Swift-BAT detection of the bright long burst GRB041219
  26. GRB 041218: Optical Observation
  27. GRB 041219: Infrared Afterglow Candidate
  28. GRB041219, BVRcIc field calibration
  29. GRB 041219: Infrared Afterglow Candidate
  30. GRB041218, BVRcIc field calibration
  31. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  32. GRB 041217: PROMPT Observations
  33. GRB041218: optical observations
  34. GRB041217: optical limit 30 min after GRB
  35. GRB 041218; optical candidate
  36. GRB 041218: Optical observations
  37. GRB 041217: LCO40 Optical Observations and Possible Candidates
  38. GRB041217: Optical Observations
  39. GRB041217: NIR and optical observations with REM
  40. GRB041217: Infrared Observations
  41. GRB041217: The First GRB Located On-Board Swift
  42. GRB041211: Faulkes Telescope continued optical monitoring
  43. Optical Transient in Lynx not a GRB
  44. Optical transient (GRB?) in Lynx
  45. GRB041211: Continued P60 Observations
  46. GRB041211, Faulkes Telescope optical observation
  47. GRB041211, BVRcIc field calibration
  48. GRB 041211: Infrared Observations
  49. GRB 041211: Optical follow-up in East Asian region
  50. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  51. GRB041015: Near-Infrared observations
  52. GRB 040924: Afterglow Color
  53. GRB 041006: GETS Optical Afterglow Observation
  54. Summary of the recent bursts from SGR 1806-20
  55. GRB 041006: Optical Observations
  56. GRB041006, late-time optical photometry
  57. GRB041006: RTT150 Optical Observations
  58. GRB041015 : Multi epoch optical observations
  59. GRB041006: RTT150 Optical Observations
  60. GRB 041016: Optical limits
  61. GRB 041015: Optical Observations at Rikubetsu
  62. GRB041006: Near Infrared observations
  63. GRB040924, BVRcIc field calibration
  64. GRB 041015: Optical limit at Osaka University
  65. GRB041015 : Optical follow-up at Kiso
  66. GRB 041006 R observations in Loiano
  67. GRB041006: VLT observations of the afterglow and host galaxy
  68. GRB041006: Optical observations and Potential host galaxy
  69. GRB041006, BVRcIc field calibration
  70. GRB 040924: VLT spectroscopy
  71. GRB 041006: SARA afterglow observations
  72. GRB041006, optical observation in CrAO
  73. Search for SN light in XRF 040912 with MEGACAM
  74. GRB 040916: Afterglow Color at Early Times
  75. GRB 041006 Optical afterglow observations
  76. GRB 041006: BR observations with VATT
  77. GRB 041006: Redshift confirmed
  78. GRB041006: Liverpool Telescope optical observations
  79. GRB 041006: Colour measurement
  80. GRB041006: break in the light curve
  81. GRB 041006: Radio Observations
  82. GRB 041006 : optical follow-up observation at Lulin Observatory
  83. GRB 041006 : Optical follow-up observation at TAROT
  84. GRB041006: Optical photometry and spectroscopy at TNG
  85. GRB 041006: presice astrometry
  86. GRB041006 (= H3570): Chandra Observations In Progress
  87. GRB 041006 : optical observation at Bisei
  88. GRB041006, optical I observation
  89. GRB041006 (=HETE3570): optical observations
  90. ROTSE-IIIa Observations of GRB 041006
  91. GRB041006, optical observation
  92. GRB041006, submillimetre observations
  93. GRB041006: MASTER optical observations
  94. GRB 041006: Optical decay
  95. GRB 041006 (=H3570): An X-Ray Rich GRB Localized in Real Time by HETE
  96. Konus-Wind observation of a series SGR 1806-20 bursts on 041005
  97. GRB041006: Fading of optical afterglow candidate
  98. GRB 041006 : Optical follow-up observation at KISO
  99. GRB 041006: Finding chart
  100. GRB 041006: Optical afterglow candidate

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