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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"

16233 results found.

  1. GRB050408: REM NIR and Optical observation
  2. GRB 050408: Moderate-resolution Gemini Spectroscopy
  3. GRB 050408,optical observation
  4. GRB 050408 Optical Observations
  5. GRB 050408: Emission and absorption redshift
  6. GRB 050408: Mercator Optical Observations
  7. GRB 050408: First Optical observations with TFOSC at the RTT150
  8. GRB 050408: steepening of the optical decay
  9. GRB 050408: Optical afterglow confirmed
  10. GRB 050408, optical observations
  11. GRB 050408 optical candidate
  12. GRB 050408: ROTSE-III Optical Limits
  13. GRB 050408 (=H3711): A Long X-Ray-Rich GRB Detected by HETE
  14. GRB050408: MASTER optical observations
  15. GRB050401: Radio Detection
  16. Swift-UVOT Optical Counterpart Candidate to XRF 050406
  17. GRB 050406: Magellan optical observations
  18. GRB 050406: Early observations with Swift-UVOT
  19. Swift-BAT detection of GRB 050406
  20. GRB050401: Radio observation at 610 MHz with GMRT
  21. GRB 050401: VLT spectroscopic redshift
  22. GRB 050401 Optical Observations
  23. GRB050401: Maidanak optical observation
  24. GRB 050401 BAT refined analysis
  25. GRB050401: TNG R-band observation
  26. GRB 050402: Early observations with Swift-UVOT
  27. GRB050401: ROTSE-III Detection of Prompt Optical Counterpart
  28. GRB 050401: Optical afterglow confirmed
  29. GRB 050401: Optical afterglow candidate
  30. GRB050331: No Afterglow Detected
  31. GRB 050331: Swift UVOT Source
  32. GRB050326: optical limit
  33. GRB 050326: Early observations with Swift-UVOT
  34. GRB050326: optical limit 33min before GRB
  35. GRB050319, optical observations
  36. GRB050319, color indices
  37. GRB050319: optical observation, March 20-22
  38. GRB050319: RTT150 Optical Observations
  39. GRB 050319: Absorption redshift from the Nordic Optical Telescope
  40. GRB 050318: Swift-BAT refined analysis
  41. Refined Swift XRT positions for GRB050315, GRB050318 and GRB050319
  42. GRB050319: VLA Observations
  43. GRB050319: radio observation
  44. GRB 050319 R band observations
  45. GRB 050319: Swift-UVOT detection of the afterglow
  46. GRB050319: Radio Observations
  47. GRB 050319: NIR afterglow candidate
  48. GRB 050319:Near IR afterglow
  49. GRB050319: BR optical photometry
  50. GRB 050319: Optical observation
  51. GRB 050319 : Confirmation of optical afterglow decay
  52. GRB050319,optical observation
  53. GRB 050319: Detection of Possible Optical Counterpart
  54. GRB 050318: Swift/UVOT detection of afterglow emission
  55. GRB 050318: Magellan optical afterglow identification
  56. GRB 050315, SMARTS optical afterglow decay
  57. GRB050223: analysis of the XMM-Newton observation
  58. GRB050316: MASTER before, simultanious and follow up optical
  59. GRB 050306: ROTSE-III early limits
  60. GRB050316: MASTER optical observations
  61. GRB 050315: Swift-BAT further refined analysis
  62. GRB 050315, SMARTS optical/IR afterglow observations
  63. GRB 050315 I-band observations
  64. GRB050315: Radio afterglow
  65. GRB 050315: Optical afterglow identification
  66. GRB 050219b: Gemini/GNIRS near-infrared spectroscopy
  67. GRB 050315: Early Observations with Swift/UVOT
  68. GRB050223: No XMM-Newton OM detection of afterglow emission
  69. GRB 050306: Radio Observations
  70. GRB050306: 250 GHz upper limit with MAMBO at the IRAM 30m
  71. GRB050309: CONCAM pre-trigger and trigger coincident optical
  72. GRB 050306: optical afterglow
  73. GRB 050309, Early optical limits from RAPTOR
  74. GRB 050306: further TAROT optical data
  75. GRB050309: Early optical limit from P60
  76. Swift 107873: P60 Optical Observations
  77. GRB 050306: CORRECTION to date of observation
  78. GRB 050306: No Swift UVOT Optical Counterpart Detected
  79. GRB 050306: REM optical-infrared observations
  80. Swift trigger 107518: optical observation
  81. GRB 050306: TAROT optical observations
  82. GRB 050306,optical observation
  83. GRB050215B: Late-Time Swift UVOT Observations
  84. PROMPT VRcIc Observations of GRB 050223
  85. GRB 050219b: candidate NIR afterglow
  86. GRB 050223: optical observations
  87. GRB050223: No Swift UVOT Detection of Afterglow Emission
  88. GRB050223: ROTSE-III Optical Observations
  89. HETE-2 Observations of GRB 050215b (=U11570): A Likely X-Ray Flash
  90. GRB050219b: No Swift UVOT Detection of Afterglow Emission
  91. GRB 050219a: Optical observations from LCO
  92. GRB 050219b: Optical and near-IR observations from LCO
  93. GRB050219b: No Swift UVOT Detection of Afterglow Emission
  94. GRB 050219a, optical observations
  95. GRB050219a: No Swift UVOT Detection of Afterglow Emission
  96. GRB050215b: Swift UVOT Detection of Afterglow Emission
  97. GRB 050215B: Radio Observations
  98. GRB 050215b: XRT confirmation of IR afterglow candidate
  99. GRB050215b: P60 Optical Observations
  100. GRB 050215b: Swift XRT Source Variability

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