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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"

20359 results found.

  1. GRB000630, Revised BVRI Field Photometry
  2. GRB000630, Optical Observations
  3. GRB000630, optical observations
  4. GRB000630, optical observations
  5. GRB000630, BVRI Field Photometry
  6. GRB000630, optical observations
  7. GRB000630: Optical observations
  8. possible optical counterpart of GRB 000630
  9. GRB 000620, optical observations
  10. GRB000418, HST/STIS Observations
  11. GRB990123: Late-time HST/STIS observations of the host
  12. GRB000620, optical observations
  13. GRB000620 - Optical observations
  14. GRB000620 Optical observations
  15. GRB000620: BeppoSAX WFC and GRBM detection
  16. GRB000615, Radio observations
  17. GRB000607, optical observations
  18. GRB 000615: NIR further observations
  19. GRB000616 optical observations
  20. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  21. GRB000615, further R-band photometry
  22. GRB 000615: NIR observations
  23. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  24. GRB000615, R-band photometry
  25. GRB 000301C: Further Late-Time HST/STIS observations
  26. GRB000528: follow-up X-ray measurements and update of IPN annulus
  27. BeppoSAX X-ray transient/possible GRB000608
  28. GRB000604 - Optical observations
  29. GRB000604, optical observations
  30. GRB000528, optical observations at ESO
  31. GRB 000418: Detection of the Host Galaxy
  32. GRB000604, optical observations, comparison with DPOSS
  33. GRB000604 [IPN Position]
  34. GRB000528, Radio Observations
  35. X-ray Afterglow of GRB 000529
  36. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  37. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  38. GRB 000528 - WFC measurements
  39. GRB000529: BeppoSAX WFC position
  40. GRB000519, BVRI field photometry
  41. IPN triangulation of GRB000519
  42. GRB000508B, optical photometry
  43. GRB000508B, BVR field photometry
  44. Possible GRB-related phenomenon
  45. RXTE/ASM and IPN localization of GRB 000508B
  46. GRB000424, UBVRI field photometry
  47. GRB000418, UBVRI field photometry update
  48. GRB000424, optical observations
  49. GRB 000429, optical observation
  50. GRB 000429, UBVRI field photometry
  51. IPN localization of GRB000429
  52. GRB 000418, UBVRI field photometry
  53. GRB 000418, optical observation
  54. GRB 000418, Optical Observation
  55. IPN error box for GRB000418
  56. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  57. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  58. Budget cuts in BeppoSAX operations: impact on GRB observations
  59. GRB 000408, optical observations
  60. GRB 991208, UBVRI field photometry
  61. GRB000301c results
  62. GRB000408, lotis optical observations
  63. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  64. GRB000301C - Addendum to GCN 623
  65. GRB 000326: Optical Observations
  66. GRB000326, Radio observations
  67. GRB000326 [IPN Position]
  68. GRB000313, Radio observations
  69. GRB 000313 - optical transient in the BATSE error box
  70. GRB000301C - R photometry
  71. GRB 000307, Optical Observations
  72. GRB 000307, BVRI Field Photometry
  73. GRB 000301C: Optical Spectrum and Redshift
  74. GRB 000301C: Optical Spectrum and Redshift
  75. GRB 000301C: A Precise Redshift Determination
  76. GRB 000301C, Optical Observation
  77. GRB 000301C: HST/STIS CCD Imaging of the field
  78. GRB000301C, optical R-band observations
  79. GRB 000301C Optical Observations
  80. GRB 000301C: K' Observations
  81. GRB000301C OT candidate optical observations
  82. GRB000301C - Host galaxy not detected in R (?)
  83. Optical observations of GRB000301c
  84. GRB000301C, Radio observations
  85. GRB000301C, Radio observations
  86. GRB 000301c near-IR observations
  87. GRB 000301C, UBVRI field photometry
  88. GRB000301C 250 GHz detection
  89. GRB 000301C R-band observation
  90. GRB000301C, near-infrared observations (JHK' photometry)
  91. GRB 000301C: OT confirmed
  92. GRB000301c optical observations
  93. GRB000301C, optical observations
  94. GRB000301c, near-infrared observations
  95. GRB000301C
  96. GRB 000301C : Optical Candidate
  97. GRB000226 [IPN Position]
  98. HST Observations of GRB 990712
  99. GRB 000214 near-IR observations
  100. GRB 000214, Radio Observations

Advanced

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