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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"

32509 results found.

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

Advanced

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