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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"

20355 results found.

  1. GRB000630, BVRI Field Photometry
  2. GRB000630, optical observations
  3. GRB000630: Optical observations
  4. possible optical counterpart of GRB 000630
  5. GRB 000620, optical observations
  6. GRB000418, HST/STIS Observations
  7. GRB990123: Late-time HST/STIS observations of the host
  8. GRB000620, optical observations
  9. GRB000620 - Optical observations
  10. GRB000620 Optical observations
  11. GRB000620: BeppoSAX WFC and GRBM detection
  12. GRB000615, Radio observations
  13. GRB000607, optical observations
  14. GRB 000615: NIR further observations
  15. GRB000616 optical observations
  16. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  17. GRB000615, further R-band photometry
  18. GRB 000615: NIR observations
  19. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  20. GRB000615, R-band photometry
  21. GRB 000301C: Further Late-Time HST/STIS observations
  22. GRB000528: follow-up X-ray measurements and update of IPN annulus
  23. BeppoSAX X-ray transient/possible GRB000608
  24. GRB000604 - Optical observations
  25. GRB000604, optical observations
  26. GRB000528, optical observations at ESO
  27. GRB 000418: Detection of the Host Galaxy
  28. GRB000604, optical observations, comparison with DPOSS
  29. GRB000604 [IPN Position]
  30. GRB000528, Radio Observations
  31. X-ray Afterglow of GRB 000529
  32. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  33. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  34. GRB 000528 - WFC measurements
  35. GRB000529: BeppoSAX WFC position
  36. GRB000519, BVRI field photometry
  37. IPN triangulation of GRB000519
  38. GRB000508B, optical photometry
  39. GRB000508B, BVR field photometry
  40. Possible GRB-related phenomenon
  41. RXTE/ASM and IPN localization of GRB 000508B
  42. GRB000424, UBVRI field photometry
  43. GRB000418, UBVRI field photometry update
  44. GRB000424, optical observations
  45. GRB 000429, optical observation
  46. GRB 000429, UBVRI field photometry
  47. IPN localization of GRB000429
  48. GRB 000418, UBVRI field photometry
  49. GRB 000418, optical observation
  50. GRB 000418, Optical Observation
  51. IPN error box for GRB000418
  52. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  53. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  54. Budget cuts in BeppoSAX operations: impact on GRB observations
  55. GRB 000408, optical observations
  56. GRB 991208, UBVRI field photometry
  57. GRB000301c results
  58. GRB000408, lotis optical observations
  59. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  60. GRB000301C - Addendum to GCN 623
  61. GRB 000326: Optical Observations
  62. GRB000326, Radio observations
  63. GRB000326 [IPN Position]
  64. GRB000313, Radio observations
  65. GRB 000313 - optical transient in the BATSE error box
  66. GRB000301C - R photometry
  67. GRB 000307, Optical Observations
  68. GRB 000307, BVRI Field Photometry
  69. GRB 000301C: Optical Spectrum and Redshift
  70. GRB 000301C: Optical Spectrum and Redshift
  71. GRB 000301C: A Precise Redshift Determination
  72. GRB 000301C, Optical Observation
  73. GRB 000301C: HST/STIS CCD Imaging of the field
  74. GRB000301C, optical R-band observations
  75. GRB 000301C Optical Observations
  76. GRB 000301C: K' Observations
  77. GRB000301C OT candidate optical observations
  78. GRB000301C - Host galaxy not detected in R (?)
  79. Optical observations of GRB000301c
  80. GRB000301C, Radio observations
  81. GRB000301C, Radio observations
  82. GRB 000301c near-IR observations
  83. GRB 000301C, UBVRI field photometry
  84. GRB000301C 250 GHz detection
  85. GRB 000301C R-band observation
  86. GRB000301C, near-infrared observations (JHK' photometry)
  87. GRB 000301C: OT confirmed
  88. GRB000301c optical observations
  89. GRB000301C, optical observations
  90. GRB000301c, near-infrared observations
  91. GRB000301C
  92. GRB 000301C : Optical Candidate
  93. GRB000226 [IPN Position]
  94. HST Observations of GRB 990712
  95. GRB 000214 near-IR observations
  96. GRB 000214, Radio Observations
  97. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  98. GRB000210, Radio Observations
  99. GRB 000115, BVRI field photometry
  100. GRB000214: BeppoSAX GRBM and WFC Detection

Advanced

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