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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"

28199 results found.

  1. GRB 041218: optical observations
  2. GRB 041219: WSRT Radio Afterglow Detection
  3. GRB 041218: Optical observations
  4. GRB 041219 : optical follow-up observations
  5. GRB 041219 Optical Observations
  6. GRB041219: Optical Afterglow Detection
  7. GRB041219: Continued NIR Observations
  8. GRB041219b: A Swift-BAT burst
  9. GRB 041219: Radio Afterglow Detection
  10. GRB 041218 : Radio Observations
  11. GRB 041218: R-band optical observations
  12. GRB041218: Liverpool Telescope optical observations
  13. GRB041218: optical observations
  14. GRB041219: Confirmed NIR Afterglow
  15. GRB041218: Continued P60 Optical Observations
  16. Swift-BAT detection of the bright long burst GRB041219
  17. GRB 041219: Infrared Afterglow Candidate
  18. GRB 041219: Infrared Afterglow Candidate
  19. GRB041218, BVRcIc field calibration
  20. GRB041218: optical observations
  21. GRB 041218: Optical observations
  22. GRB 041217: LCO40 Optical Observations and Possible Candidates
  23. GRB041217: Infrared Observations
  24. Optical transient (GRB?) in Lynx
  25. GRB041211, BVRcIc field calibration
  26. GRB041211: P60 optical imaging
  27. GRB970815: Discovery of Optical Afterglow
  28. Distribution of IBAS Alerts for NON-GRB sources
  29. GRB 040924: Afterglow Color
  30. GRB 041006: GETS Optical Afterglow Observation
  31. GRB 041006: Optical Observations
  32. GRB041006, late-time optical photometry
  33. GRB041006: RTT150 Optical Observations
  34. HST Observations: XRF 040701 and 040812
  35. GRB041006: RTT150 Optical Observations
  36. GRB 041016: Optical limits
  37. GRB041006: Near Infrared observations
  38. GRB040924, BVRcIc field calibration
  39. GRB041006: Fading X-ray Afterglow Observed with Chandra
  40. GRB041006: VLT observations of the afterglow and host galaxy
  41. GRB041006: Optical observations and Potential host galaxy
  42. GRB041006, BVRcIc field calibration
  43. GRB 041006: SARA afterglow observations
  44. Search for SN light in XRF 040912 with MEGACAM
  45. GRB 040916: Afterglow Color at Early Times
  46. GRB 041006 Optical afterglow observations
  47. GRB 041006: BR observations with VATT
  48. GRB 041006: Redshift confirmed
  49. GRB041006: Liverpool Telescope optical observations
  50. GRB 041006: Colour measurement
  51. GRB041006: break in the light curve
  52. GRB 041006: Radio Observations
  53. GRB041006, further submilllimetre observations
  54. GRB 041006 : optical follow-up observation at Lulin Observatory
  55. GRB 041006 : Optical follow-up observation at TAROT
  56. GRB041006: Optical photometry and spectroscopy at TNG
  57. GRB041006 (= H3570): Chandra Observations In Progress
  58. GRB 041006 : optical observation at Bisei
  59. GRB041006, optical I observation
  60. GRB041006, submillimetre observations
  61. GRB 041006: Optical decay
  62. GRB041006: Fading of optical afterglow candidate
  63. GRB 041006: Finding chart
  64. GRB 041006: Optical afterglow candidate
  65. GRB 040924: Second Epoch WSRT Radio Observations
  66. radio observations, GRB 040924
  67. GRB040924,optical observation
  68. GRB040924, RTT150 optical observation
  69. GRB 040924: detection of possible host galaxy by Subaru
  70. GRB040924, RTT150 optical observation
  71. GRB040924: Afterglow magnitude at t=17.5hr
  72. GRB 040924: WSRT Radio Observations
  73. GRB 040924: Subaru NIR observation
  74. GRB040924: Optical afterglow properties
  75. GRB 040924, optical follow-up
  76. GRB040924 (H3564): Optical afterglow candidate
  77. XRF 040912: Radio Observations
  78. XRF 040916: Radio Observations
  79. GRB040912(=H3557): Chandra Candidate X-ray Afterglow
  80. TAROT Observations of GRB 040916 (HETE #3558)
  81. GRB040912(=H3557): Candidate Optical Afterglow
  82. XRF040912, BVRcIc field calibration
  83. XRF040916, BVRcIc field calibration
  84. GRB040916: Archival optical observations
  85. GRB 040912: Optical Observations
  86. GRB 040912, BVRI observations
  87. HETE 3557: Optical observations
  88. GRB040827: analysis of the XMM-Newton observation
  89. GRB040903, REM near-IR observation
  90. GRB 040827 - Radio Observations
  91. XMM-Newton Images of GRB 040827
  92. GRB040825A: Optical observations
  93. GRB040825A: Optical observations
  94. GRB 040827: optical and NIR observations at the VLT
  95. GRB 040827: UKIRT - 2nd epoch K-band imaging
  96. GRB 040827: 2nd epoch of Magellan K-band imaging
  97. GRB 040827: Detection of NIR afterglow
  98. GRB 040827: Possible detection of optical afterglow
  99. GRB040825B, BVRcIc field photometry
  100. GRB040825A, BVRcIc field photometry

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