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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"

36109 results found.

  1. GRB 041219: Radio Afterglow Detection
  2. GRB 041218 : Radio Observations
  3. GRB 041218: R-band optical observations
  4. GRB041219: Confirmed NIR Afterglow
  5. GRB041218: Continued P60 Optical Observations
  6. GRB 041218: Optical Observation
  7. GRB 041219: Infrared Afterglow Candidate
  8. GRB041219, BVRcIc field calibration
  9. GRB 041219: Infrared Afterglow Candidate
  10. GRB041218, BVRcIc field calibration
  11. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  12. GRB041219: P60 Optical Observations
  13. GRB 041219 - A long GRB detected by INTEGRAL
  14. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  15. GRB 041217: PROMPT Observations
  16. GRB041218: optical observations
  17. GRB041217: optical limit 30 min after GRB
  18. GRB 041218; optical candidate
  19. GRB 041218: Optical observations
  20. GRB 041217: LCO40 Optical Observations and Possible Candidates
  21. GRB 041218 - A long GRB detected by integral
  22. GRB041217: Optical Observations
  23. GRB041217: P60 Optical Observations
  24. GRB041217: Infrared Observations
  25. GRB041217: The First GRB Located On-Board Swift
  26. GRB041211: Faulkes Telescope continued optical monitoring
  27. Optical Transient in Lynx not a GRB
  28. Optical transient (GRB?) in Lynx
  29. Optical transient (GRB?) in Lynx, UT Dec 11.4436
  30. GRB041211: Continued P60 Observations
  31. GRB041211: RAPTOR observations
  32. GRB041211: Ashra Prototype optical observation
  33. GRB041211, Faulkes Telescope optical observation
  34. GRB041211, BVRcIc field calibration
  35. GRB 041211: Infrared Observations
  36. GRB 041211: KAIT observations
  37. GRB 041211: Optical follow-up in East Asian region
  38. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  39. GRB041211: P60 optical imaging
  40. GRB970815: Discovery of Optical Afterglow
  41. Distribution of IBAS Alerts for NON-GRB sources
  42. Triangulation of short GRB 041116 (large error box)
  43. GRB 040924: Afterglow Color
  44. GRB 041006: GETS Optical Afterglow Observation
  45. Summary of the recent bursts from SGR 1806-20
  46. GRB 041006: Optical Observations
  47. GRB041006, late-time optical photometry
  48. IBAS GRB Alert # 2034
  49. GRB041006: RTT150 Optical Observations
  50. Bright bursts from SGR1806-20
  51. GRB 041016: BOOTES-2 simultaneous observation
  52. GRB041006: RTT150 Optical Observations
  53. GRB 041016: Optical limits
  54. GRB 041016: Optical limits in V, R, I
  55. GRB 041016:Optical limit during first minute
  56. GRB041016: MASTER: Optical observations
  57. GRB 041015: Optical Observations at Rikubetsu
  58. GRB041006: Near Infrared observations
  59. GRB 041016: Optical limit
  60. GRB 041015 R band observations
  61. GRB040924, BVRcIc field calibration
  62. GRB041015: MASTER: Optical observations
  63. GRB041015,optical observation
  64. GRB 041015: Optical limit at Osaka University
  65. GRB041015 : Optical follow-up at Kiso
  66. GRB 041015 - A long GRB detected by INTEGRAL
  67. GRB 041006 R observations in Loiano
  68. GRB041006: VLT observations of the afterglow and host galaxy
  69. GRB041006: Optical observations and Potential host galaxy
  70. GRB041006, BVRcIc field calibration
  71. GRB 040924: VLT spectroscopy
  72. GRB 041006: SARA afterglow observations
  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. IBAS GRB Alert # 2010
  77. GRB 041006: BR observations with VATT
  78. GRB 041006: Redshift confirmed
  79. GRB041006: Liverpool Telescope optical observations
  80. GRB 041006: Colour measurement
  81. GRB041006: break in the light curve
  82. GRB 041006: Radio Observations
  83. GRB041006, further submilllimetre observations
  84. GRB 041006 : optical follow-up observation at Lulin Observatory
  85. GRB 041006 : Optical follow-up observation at TAROT
  86. GRB041006: Optical photometry and spectroscopy at TNG
  87. GRB 041006: presice astrometry
  88. GRB041006 (= H3570): Chandra Observations In Progress
  89. GRB 041006 : optical observation at Bisei
  90. GRB041006 (=HETE3570): optical observations
  91. ROTSE-IIIa Observations of GRB 041006
  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. GRB 041006 : Optical follow-up observation at KISO
  97. GRB 041006: Finding chart
  98. GRB 041006: Optical afterglow candidate
  99. XRF 020903: Observations of the Host Galaxy (authors)
  100. GRB 040924: Second Epoch WSRT Radio Observations

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