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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"

32511 results found.

  1. GRB 000615: NIR further observations
  2. GRB990123, HST/STIS observations of the host galaxy
  3. GRB000616 optical observations
  4. GRB 000615, near-infrared observations
  5. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  6. GRB000615, further R-band photometry
  7. GRB 000615: NIR observations
  8. GRB000615, R-band photometry
  9. GRB980425, HST/STIS observations of the host galaxy
  10. The Hosts of GRB 980703 and GRB 971214
  11. GRB 000301C: Further Late-Time HST/STIS observations
  12. GRB000528: follow-up X-ray measurements and update of IPN annulus
  13. Optical Follow-up of GRB000529 Error Box
  14. GRB000607, Radio Observations
  15. GRB000604 optical non-detection
  16. GRB000604 - Optical observations
  17. GRB000604, optical observations
  18. GRB000528, optical observations at ESO
  19. GRB 000604 optical observations
  20. GRB 000418: Detection of the Host Galaxy
  21. GRB000604, optical observations, comparison with DPOSS
  22. GRB000528, Radio Observations
  23. X-ray Afterglow of GRB 000529
  24. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  25. IPN localization and time history of GRB000528
  26. New IPN localization of GRB000529
  27. GRB000519: Optical observations
  28. IPN localization of GRB000529
  29. GRB 000528 - WFC measurements
  30. IPN triangulation of GRB000519
  31. Re: GRB000508B : Optical observations
  32. GRB 000418, Optical observation
  33. GRB000508B, optical photometry
  34. Possible GRB-related phenomenon
  35. GRB 000424 Optical Observations
  36. The redshift of GRB 000418
  37. GRB000424, optical observations
  38. GRB 000429, optical observation
  39. GRB000418, Radio detection
  40. GRB000418, K'-band photometry
  41. GRB 000418, Optical Observation
  42. GRB 000418, optical observation
  43. GRB000424 Optical Observations
  44. GRB 000418, Optical Observation
  45. GRB000424, optical observations
  46. GRB000424, optical observations
  47. GRB 000424, Optical Observations
  48. GRB 000418, Optical Observation
  49. GRB000418, near-infrared observations
  50. BeppoSAX GRB000424
  51. Correction to IPN error box for GRB000419
  52. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  53. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  54. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  55. GRB 000408, optical observations
  56. Refined IPN error box for GRB000408
  57. GRB000301c results
  58. GRB000408: Optical CCD Observations from MIRO
  59. GRB000408, lotis optical observations
  60. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  61. GRB000326 Optical Observations
  62. GRB000301C - Addendum to GCN 623
  63. GRB000326, Further VLA observations
  64. GRB 000323, optical observations
  65. GRB 000326: Optical Observations
  66. GRB000326, Radio observations
  67. GRB 000307 optical observations
  68. Single error box for GRB000315
  69. GRB000313, Radio observations
  70. GRB000301C - B and R photometry
  71. GRB 000307, Optical Observations
  72. GRB 000301C: Optical Spectrum and Redshift
  73. GRB 000301C: Optical Spectrum and Redshift
  74. GRB 000301C: A Precise Redshift Determination
  75. GRB 000301C, Optical Observation
  76. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  77. GRB 000301C: HST/STIS CCD Imaging of the field
  78. GRB000301C, optical R-band observations
  79. GRB000301c - R photometry and nearby faint source confirmation
  80. GRB 000301C, Optical Observation
  81. GRB 000301C Optical Observations
  82. GRB 000301C: K' Observations
  83. GRB000301C OT candidate optical observations
  84. Optical observations of GRB000301c
  85. GRB000301C, Radio observations
  86. GRB000301C, Radio observations
  87. GRB000301C, near-infrared observations (JHK' imaging)
  88. GRB 000301C, Optical Color
  89. GRB 000301C, UBVRI field photometry
  90. GRB 000301C, Optical Observation
  91. GRB000301C, optical observations
  92. GRB000301C 250 GHz detection
  93. GRB 000301C R-band observation
  94. GRB 000301C, Optical Observation
  95. GRB000301C, near-infrared observations (JHK' photometry)
  96. GRB 000301C: OT confirmed
  97. GRB000301c optical observations
  98. GRB 000301A, Radio Observations
  99. GRB000301C, optical observations
  100. GRB000301c, near-infrared observations

Advanced

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