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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"

21791 results found.

  1. GRB000630, Optical Observations
  2. GRB000630, optical observations
  3. GRB000630, optical observations
  4. GRB000630, optical observations
  5. GRB000630, optical observations
  6. GRB000630: Optical observations
  7. GRB000630, Radio Observations
  8. possible optical counterpart of GRB 000630
  9. GRB 000623, optical observations
  10. GRB 000620, optical observations
  11. GRB000418, HST/STIS Observations
  12. GRB990123: Late-time HST/STIS observations of the host
  13. GRB 990506, HST/STIS Observations of the Host Galaxy
  14. GRB 000620: J-band observations
  15. GRB000620, optical observations
  16. GRB000615: H-band observations
  17. GRB990308, HST/STIS observations of the host galaxy
  18. GRB000620 - Optical observations
  19. GRB000620 Optical observations
  20. GRB000615, Radio observations
  21. GRB000607, optical observations
  22. GRB 000615: NIR further observations
  23. GRB990123, HST/STIS observations of the host galaxy
  24. GRB000616 optical observations
  25. GRB 000615, near-infrared observations
  26. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  27. GRB000615, further R-band photometry
  28. GRB 000615: NIR observations
  29. GRB000615, R-band photometry
  30. GRB980425, HST/STIS observations of the host galaxy
  31. The Hosts of GRB 980703 and GRB 971214
  32. GRB 000301C: Further Late-Time HST/STIS observations
  33. GRB980519, HST/STIS observations of the host galaxy
  34. GRB000607, Radio Observations
  35. GRB000604 - Optical observations
  36. GRB000604, optical observations
  37. GRB000528, optical observations at ESO
  38. GRB 000604 optical observations
  39. GRB 000418: Detection of the Host Galaxy
  40. GRB000604, optical observations, comparison with DPOSS
  41. GRB000528, Radio Observations
  42. GRB000529: Optical Observations
  43. GRB000519: Optical observations
  44. GRB000528: BeppoSAX GRBM observations
  45. GRB 000528 Optical Observations
  46. Re: GRB000508B : Optical observations
  47. GRB 000418, Optical observation
  48. GRB000508B, optical photometry
  49. Possible GRB-related phenomenon
  50. GRB 000424 Optical Observations
  51. GRB000418, UBVRI field photometry update
  52. The redshift of GRB 000418
  53. GRB000424, optical observations
  54. GRB 000418, Optical Observation
  55. GRB000424 Optical Observations
  56. GRB000424, optical observations
  57. GRB000424, optical observations
  58. GRB 000424, Optical Observations
  59. GRB 000418, Optical Observation
  60. GRB000418, near-infrared observations
  61. GRB000416 Optical Observations
  62. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  63. GRB000416 BRJK observations
  64. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  65. Budget cuts in BeppoSAX operations: impact on GRB observations
  66. GRB 000408, optical observations
  67. GRB000408: Optical CCD Observations from MIRO
  68. GRB000408, lotis optical observations
  69. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  70. GRB000326 Optical Observations
  71. GRB000301C - Addendum to GCN 623
  72. GRB000301C - R magnitude lower limit
  73. GRB000326, Further VLA observations
  74. GRB 000323, optical observations
  75. GRB 000326: Optical Observations
  76. GRB000326, Radio observations
  77. GRB 000307 optical observations
  78. GRB000313, Radio observations
  79. GRB 000313 - optical transient in the BATSE error box
  80. GRB000301C - B and R photometry
  81. GRB 000307, Optical Observations
  82. GRB 000301C: A Precise Redshift Determination
  83. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  84. GRB 000301C: HST/STIS CCD Imaging of the field
  85. GRB 000301c: K' observations
  86. GRB000301C, optical R-band observations
  87. GRB000301c - R photometry and nearby faint source confirmation
  88. GRB 000301C, Optical Observation
  89. GRB 000301c: K' observations
  90. GRB 000301C Optical Observations
  91. GRB 000301C: K' Observations
  92. GRB000301C OT candidate optical observations
  93. GRB000301C - Host galaxy not detected in R (?)
  94. Optical observations of GRB000301c
  95. GRB000301C, Radio observations
  96. GRB000301C, Radio observations
  97. GRB000301C optical observations
  98. GRB000301C, near-infrared observations (JHK' imaging)
  99. GRB 000301c near-IR observations
  100. GRB000301C, optical observations

Advanced

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