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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

15714 results found.

  1. GRB000607, optical observations
  2. GRB990123, HST/STIS observations of the host galaxy
  3. GRB000616 optical observations
  4. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  5. GRB000615, further R-band photometry
  6. The Hosts of GRB 980703 and GRB 971214
  7. GRB 000301C: Further Late-Time HST/STIS observations
  8. Optical Follow-up of GRB000529 Error Box
  9. GRB000604 optical non-detection
  10. GRB000604 - Optical observations
  11. GRB000604, optical observations
  12. GRB000528, optical observations at ESO
  13. GRB 000604 optical observations
  14. GRB 000418: Detection of the Host Galaxy
  15. GRB000604, optical observations, comparison with DPOSS
  16. GRB000529: Optical Observations
  17. GRB000519: Optical observations
  18. GRB 000528 Optical Observations
  19. GRB000519, BVRI field photometry
  20. Re: GRB000508B : Optical observations
  21. GRB 000418, Optical observation
  22. GRB000508B, optical photometry
  23. GRB000508B, BVR field photometry
  24. Possible GRB-related phenomenon
  25. GRB000424, UBVRI field photometry
  26. GRB 000424 Optical Observations
  27. GRB000418, UBVRI field photometry update
  28. GRB000424, optical observations
  29. GRB 000429, optical observation
  30. GRB 000429, UBVRI field photometry
  31. GRB000418, Radio detection
  32. GRB 000418, Optical Observation
  33. GRB 000418, optical observation
  34. GRB000424 Optical Observations
  35. GRB 000418, Optical Observation
  36. GRB000424, optical observations
  37. GRB000424, optical observations
  38. GRB 000424, Optical Observations
  39. GRB 000418, Optical Observation
  40. GRB000416 Optical Observations
  41. GRB000416 BRJK observations
  42. GRB 000408, optical observations
  43. GRB 991208, UBVRI field photometry
  44. GRB000301c results
  45. GRB000408: Optical CCD Observations from MIRO
  46. GRB000408, lotis optical observations
  47. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  48. GRB000326 Optical Observations
  49. GRB000301C - R magnitude lower limit
  50. GRB 000323, optical observations
  51. GRB 000326: Optical Observations
  52. GRB 000307 optical observations
  53. GRB000313, Radio observations
  54. GRB 000313 - optical transient in the BATSE error box
  55. GRB000301C - B and R photometry
  56. GRB000301C - R photometry
  57. GRB 000307, Optical Observations
  58. GRB 000307, BVRI Field Photometry
  59. GRB 000301C: Optical Spectrum and Redshift
  60. GRB 000301C: Optical Spectrum and Redshift
  61. GRB 000301C: A Precise Redshift Determination
  62. GRB 000301C, Optical Observation
  63. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  64. GRB 000301c: K' observations
  65. GRB000301C, optical R-band observations
  66. GRB000301c - R photometry and nearby faint source confirmation
  67. GRB 000301C, Optical Observation
  68. GRB 000301C Optical Observations
  69. GRB 000301C: K' Observations
  70. GRB000301C OT candidate optical observations
  71. GRB000301C - Host galaxy not detected in R (?)
  72. Optical observations of GRB000301c
  73. GRB000301C, Radio observations
  74. GRB000301C, Radio observations
  75. GRB000301C optical observations
  76. GRB 000301c near-IR observations
  77. GRB 000301C, Optical Color
  78. GRB000301C, Optical Spectroscopy
  79. GRB 000301C, UBVRI field photometry
  80. GRB 000301C, Optical Observation
  81. GRB000301C, optical observations
  82. GRB 000301C R-band observation
  83. GRB 000301C, Optical Observation
  84. GRB000301C, near-infrared observations (JHK' photometry)
  85. GRB 000301C: OT confirmed
  86. GRB000301c optical observations
  87. GRB000301C, optical observations
  88. GRB000301c, near-infrared observations
  89. GRB 000301C : Optical Candidate
  90. GRB 000115 Optical observations
  91. GRB 000115, BVRI field photometry
  92. Optical observations of GRB000210
  93. GRB000210 X-ray afterglow
  94. Correction to Chandra Position of GRB000210 afterglow
  95. Optical observations of the Chandra X-ray source for GRB000210
  96. Optical candidate for GRB000210
  97. GRB000201, Radio Observations
  98. Optical observations of GRB000131
  99. GRB000201 Optical Observations
  100. GRB 000201: TAROT optical observations

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