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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"

21793 results found.

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

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
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