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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"

20366 results found.

  1. IPN localization of GRB000730B
  2. IPN localization of GRB000730B
  3. GRB 990510: Possible detection of a host galaxy
  4. GRB 990510 Host Galaxy Discovery
  5. GRB 990712: Late time HST/STIS Observations
  6. GRB 991216, HST/STIS observations
  7. GRB000630, optical observations
  8. GRB000630, Revised BVRI Field Photometry
  9. GRB000630, Optical Observations
  10. GRB000630, optical observations
  11. GRB000630, optical observations
  12. GRB000630, BVRI Field Photometry
  13. GRB000630, optical observations
  14. GRB000630: Optical observations
  15. possible optical counterpart of GRB 000630
  16. GRB 000620, optical observations
  17. GRB000418, HST/STIS Observations
  18. GRB990123: Late-time HST/STIS observations of the host
  19. GRB000620, optical observations
  20. GRB000620 - Optical observations
  21. GRB000620 Optical observations
  22. GRB000620: BeppoSAX WFC and GRBM detection
  23. GRB000615, Radio observations
  24. GRB000607, optical observations
  25. GRB 000615: NIR further observations
  26. GRB000616 optical observations
  27. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  28. GRB000615, further R-band photometry
  29. GRB 000615: NIR observations
  30. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  31. GRB000615, R-band photometry
  32. GRB 000301C: Further Late-Time HST/STIS observations
  33. GRB000528: follow-up X-ray measurements and update of IPN annulus
  34. BeppoSAX X-ray transient/possible GRB000608
  35. GRB000604 - Optical observations
  36. GRB000604, optical observations
  37. GRB000528, optical observations at ESO
  38. GRB 000418: Detection of the Host Galaxy
  39. GRB000604, optical observations, comparison with DPOSS
  40. GRB000604 [IPN Position]
  41. GRB000528, Radio Observations
  42. X-ray Afterglow of GRB 000529
  43. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  44. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  45. GRB 000528 - WFC measurements
  46. GRB000529: BeppoSAX WFC position
  47. GRB000519, BVRI field photometry
  48. IPN triangulation of GRB000519
  49. GRB000508B, optical photometry
  50. GRB000508B, BVR field photometry
  51. Possible GRB-related phenomenon
  52. RXTE/ASM and IPN localization of GRB 000508B
  53. GRB000424, UBVRI field photometry
  54. GRB000418, UBVRI field photometry update
  55. GRB000424, optical observations
  56. GRB 000429, optical observation
  57. GRB 000429, UBVRI field photometry
  58. IPN localization of GRB000429
  59. GRB 000418, UBVRI field photometry
  60. GRB 000418, optical observation
  61. GRB 000418, Optical Observation
  62. IPN error box for GRB000418
  63. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  64. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  65. Budget cuts in BeppoSAX operations: impact on GRB observations
  66. GRB 000408, optical observations
  67. GRB 991208, UBVRI field photometry
  68. GRB000301c results
  69. GRB000408, lotis optical observations
  70. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  71. GRB000301C - Addendum to GCN 623
  72. GRB 000326: Optical Observations
  73. GRB000326, Radio observations
  74. GRB000326 [IPN Position]
  75. GRB000313, Radio observations
  76. GRB 000313 - optical transient in the BATSE error box
  77. GRB000301C - R photometry
  78. GRB 000307, Optical Observations
  79. GRB 000307, BVRI Field Photometry
  80. GRB 000301C: Optical Spectrum and Redshift
  81. GRB 000301C: Optical Spectrum and Redshift
  82. GRB 000301C: A Precise Redshift Determination
  83. GRB 000301C, Optical Observation
  84. GRB 000301C: HST/STIS CCD Imaging of the field
  85. GRB000301C, optical R-band observations
  86. GRB 000301C Optical Observations
  87. GRB 000301C: K' Observations
  88. GRB000301C OT candidate optical observations
  89. GRB000301C - Host galaxy not detected in R (?)
  90. Optical observations of GRB000301c
  91. GRB000301C, Radio observations
  92. GRB000301C, Radio observations
  93. GRB 000301c near-IR observations
  94. GRB 000301C, UBVRI field photometry
  95. GRB000301C 250 GHz detection
  96. GRB 000301C R-band observation
  97. GRB000301C, near-infrared observations (JHK' photometry)
  98. GRB 000301C: OT confirmed
  99. GRB000301c optical observations
  100. GRB000301C, optical observations

Advanced

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