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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"

37711 results found.

  1. GRB041219: Continued NIR Observations
  2. GRB 041219 ,optical observation
  3. GRB 041219: Radio Afterglow Detection
  4. GRB 041218 : Radio Observations
  5. GRB 041218: R-band optical observations
  6. GRB041219: Confirmed NIR Afterglow
  7. GRB041218: Continued P60 Optical Observations
  8. GRB 041218: Optical Observation
  9. GRB 041219: Infrared Afterglow Candidate
  10. GRB041219, BVRcIc field calibration
  11. GRB 041219: Infrared Afterglow Candidate
  12. GRB041218, BVRcIc field calibration
  13. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  14. GRB041219: P60 Optical Observations
  15. GRB 041219 - A long GRB detected by INTEGRAL
  16. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  17. GRB 041217: PROMPT Observations
  18. GRB041218: optical observations
  19. GRB041217: optical limit 30 min after GRB
  20. GRB 041218; optical candidate
  21. GRB 041218: Optical observations
  22. GRB 041217: LCO40 Optical Observations and Possible Candidates
  23. GRB 041218 - A long GRB detected by integral
  24. GRB041217: Optical Observations
  25. GRB041217: P60 Optical Observations
  26. GRB041217: Infrared Observations
  27. GRB041217: The First GRB Located On-Board Swift
  28. GRB041211: Faulkes Telescope continued optical monitoring
  29. Optical Transient in Lynx not a GRB
  30. Optical transient (GRB?) in Lynx
  31. Optical transient (GRB?) in Lynx, UT Dec 11.4436
  32. GRB041211: Continued P60 Observations
  33. GRB041211: RAPTOR observations
  34. GRB041211: Ashra Prototype optical observation
  35. GRB041211, Faulkes Telescope optical observation
  36. GRB041211, BVRcIc field calibration
  37. GRB 041211: Infrared Observations
  38. GRB 041211: KAIT observations
  39. GRB 041211: Optical follow-up in East Asian region
  40. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  41. GRB041211: P60 optical imaging
  42. GRB970815: Discovery of Optical Afterglow
  43. Distribution of IBAS Alerts for NON-GRB sources
  44. Triangulation of short GRB 041116 (large error box)
  45. GRB 040924: Afterglow Color
  46. GRB 041006: GETS Optical Afterglow Observation
  47. Summary of the recent bursts from SGR 1806-20
  48. GRB 041006: Optical Observations
  49. GRB041006, late-time optical photometry
  50. IBAS GRB Alert # 2034
  51. GRB041006: RTT150 Optical Observations
  52. Bright bursts from SGR1806-20
  53. GRB 041016: BOOTES-2 simultaneous observation
  54. GRB041006: RTT150 Optical Observations
  55. GRB 041016: Optical limits
  56. GRB 041016: Optical limits in V, R, I
  57. GRB 041016:Optical limit during first minute
  58. GRB041016: MASTER: Optical observations
  59. GRB 041015: Optical Observations at Rikubetsu
  60. GRB041006: Near Infrared observations
  61. GRB 041016: Optical limit
  62. GRB 041015 R band observations
  63. GRB040924, BVRcIc field calibration
  64. GRB041015: MASTER: Optical observations
  65. GRB041015,optical observation
  66. GRB 041015: Optical limit at Osaka University
  67. GRB041015 : Optical follow-up at Kiso
  68. GRB 041015 - A long GRB detected by INTEGRAL
  69. GRB 041006 R observations in Loiano
  70. GRB041006: VLT observations of the afterglow and host galaxy
  71. GRB041006: Optical observations and Potential host galaxy
  72. GRB041006, BVRcIc field calibration
  73. GRB 040924: VLT spectroscopy
  74. GRB 041006: SARA afterglow observations
  75. Search for SN light in XRF 040912 with MEGACAM
  76. GRB 040916: Afterglow Color at Early Times
  77. GRB 041006 Optical afterglow observations
  78. IBAS GRB Alert # 2010
  79. GRB 041006: BR observations with VATT
  80. GRB 041006: Redshift confirmed
  81. GRB041006: Liverpool Telescope optical observations
  82. GRB 041006: Colour measurement
  83. GRB041006: break in the light curve
  84. GRB 041006: Radio Observations
  85. GRB041006, further submilllimetre observations
  86. GRB 041006 : optical follow-up observation at Lulin Observatory
  87. GRB 041006 : Optical follow-up observation at TAROT
  88. GRB041006: Optical photometry and spectroscopy at TNG
  89. GRB 041006: presice astrometry
  90. GRB041006 (= H3570): Chandra Observations In Progress
  91. GRB 041006 : optical observation at Bisei
  92. GRB041006 (=HETE3570): optical observations
  93. ROTSE-IIIa Observations of GRB 041006
  94. GRB041006, submillimetre observations
  95. GRB041006: MASTER optical observations
  96. GRB 041006: Optical decay
  97. GRB 041006 (=H3570): An X-Ray Rich GRB Localized in Real Time by HETE
  98. GRB 041006 : Optical follow-up observation at KISO
  99. GRB 041006: Finding chart
  100. GRB 041006: Optical afterglow candidate

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