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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"

19074 results found.

  1. GRB000911, Radio and Optical observations
  2. GRB000911: Optical observations
  3. IPN triangulation of GRB000910
  4. GRB000830, BVRI field photometry
  5. GRB000801, VLT-Antu R-band observations
  6. GRB000301C, UBVI optical observations
  7. GRB000801, Radio Observations
  8. GRB 991208 Host Galaxy Imaging
  9. IPN localization of GRB000730B
  10. IPN localization of GRB000730B
  11. GRB 990510: Possible detection of a host galaxy
  12. GRB 990510 Host Galaxy Discovery
  13. GRB 990712: Late time HST/STIS Observations
  14. GRB 991216, HST/STIS observations
  15. GRB000630, optical observations
  16. GRB000630, Revised BVRI Field Photometry
  17. GRB000630, Optical Observations
  18. GRB000630, optical observations
  19. GRB000630, optical observations
  20. GRB000630, BVRI Field Photometry
  21. GRB000630, optical observations
  22. GRB000630: Optical observations
  23. possible optical counterpart of GRB 000630
  24. GRB 000620, optical observations
  25. GRB000418, HST/STIS Observations
  26. GRB990123: Late-time HST/STIS observations of the host
  27. GRB000620, optical observations
  28. GRB000620 - Optical observations
  29. GRB000620 Optical observations
  30. GRB000620: BeppoSAX WFC and GRBM detection
  31. GRB000615, Radio observations
  32. GRB000607, optical observations
  33. GRB 000615: NIR further observations
  34. GRB000616 optical observations
  35. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  36. GRB000615, further R-band photometry
  37. GRB 000615: NIR observations
  38. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  39. GRB000615, R-band photometry
  40. GRB 000301C: Further Late-Time HST/STIS observations
  41. GRB000528: follow-up X-ray measurements and update of IPN annulus
  42. BeppoSAX X-ray transient/possible GRB000608
  43. GRB000604 - Optical observations
  44. GRB000604, optical observations
  45. GRB000528, optical observations at ESO
  46. GRB 000418: Detection of the Host Galaxy
  47. GRB000604, optical observations, comparison with DPOSS
  48. GRB000604 [IPN Position]
  49. GRB000528, Radio Observations
  50. X-ray Afterglow of GRB 000529
  51. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  52. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  53. GRB 000528 - WFC measurements
  54. GRB000529: BeppoSAX WFC position
  55. GRB000519, BVRI field photometry
  56. IPN triangulation of GRB000519
  57. GRB000508B, optical photometry
  58. GRB000508B, BVR field photometry
  59. Possible GRB-related phenomenon
  60. RXTE/ASM and IPN localization of GRB 000508B
  61. GRB000424, UBVRI field photometry
  62. GRB000418, UBVRI field photometry update
  63. GRB000424, optical observations
  64. GRB 000429, optical observation
  65. GRB 000429, UBVRI field photometry
  66. IPN localization of GRB000429
  67. GRB 000418, UBVRI field photometry
  68. GRB 000418, optical observation
  69. GRB 000418, Optical Observation
  70. IPN error box for GRB000418
  71. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  72. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  73. Budget cuts in BeppoSAX operations: impact on GRB observations
  74. GRB 000408, optical observations
  75. GRB 991208, UBVRI field photometry
  76. GRB000301c results
  77. GRB000408, lotis optical observations
  78. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  79. GRB000301C - Addendum to GCN 623
  80. GRB 000326: Optical Observations
  81. GRB000326, Radio observations
  82. GRB000326 [IPN Position]
  83. GRB000313, Radio observations
  84. GRB 000313 - optical transient in the BATSE error box
  85. GRB000301C - R photometry
  86. GRB 000307, Optical Observations
  87. GRB 000307, BVRI Field Photometry
  88. GRB 000301C: Optical Spectrum and Redshift
  89. GRB 000301C: Optical Spectrum and Redshift
  90. GRB 000301C: A Precise Redshift Determination
  91. GRB 000301C, Optical Observation
  92. GRB 000301C: HST/STIS CCD Imaging of the field
  93. GRB000301C, optical R-band observations
  94. GRB 000301C Optical Observations
  95. GRB 000301C: K' Observations
  96. GRB000301C OT candidate optical observations
  97. GRB000301C - Host galaxy not detected in R (?)
  98. Optical observations of GRB000301c
  99. GRB000301C, Radio observations
  100. GRB000301C, Radio observations

Advanced

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