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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"

31741 results found.

  1. GRB 990705, HST/STIS observations of the host galaxy
  2. GRB 990712: Late time HST/STIS Observations
  3. GRB 991216, HST/STIS observations
  4. GRB000620, Radio Observations
  5. GRB981226, HST/STIS observations of the host galaxy
  6. GRB000630, optical observations
  7. GRB 000630: Detection of the Optical Afterglow
  8. GRB000630, Revised BVRI Field Photometry
  9. GRB000630, Optical Observations
  10. GRB000630, optical observations
  11. GRB000630, optical observations
  12. GRB000630, optical observations
  13. GRB000630, optical observations
  14. GRB000630: Optical observations
  15. GRB000630, Radio Observations
  16. possible optical counterpart of GRB 000630
  17. GRB 000623, optical observations
  18. GRB 000620, optical observations
  19. GRB000418, HST/STIS Observations
  20. GRB990123: Late-time HST/STIS observations of the host
  21. GRB 990506, HST/STIS Observations of the Host Galaxy
  22. GRB 000620: J-band observations
  23. GRB000620, optical observations
  24. GRB000615: H-band observations
  25. GRB990308, HST/STIS observations of the host galaxy
  26. GRB000620 - Optical observations
  27. GRB000620 Optical observations
  28. IPN annulus for GRB000620
  29. GRB000615, Radio observations
  30. GRB000607, optical observations
  31. GRB 000615: NIR further observations
  32. GRB990123, HST/STIS observations of the host galaxy
  33. GRB000616 optical observations
  34. GRB 000615, near-infrared 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, R-band photometry
  39. GRB980425, HST/STIS observations of the host galaxy
  40. The Hosts of GRB 980703 and GRB 971214
  41. GRB 000301C: Further Late-Time HST/STIS observations
  42. GRB000528: follow-up X-ray measurements and update of IPN annulus
  43. Optical Follow-up of GRB000529 Error Box
  44. GRB000607, Radio Observations
  45. GRB000604 optical non-detection
  46. GRB000604 - Optical observations
  47. GRB000604, optical observations
  48. GRB000528, optical observations at ESO
  49. GRB 000604 optical observations
  50. GRB 000418: Detection of the Host Galaxy
  51. GRB000604, optical observations, comparison with DPOSS
  52. GRB000528, Radio Observations
  53. X-ray Afterglow of GRB 000529
  54. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  55. IPN localization and time history of GRB000528
  56. New IPN localization of GRB000529
  57. GRB000519: Optical observations
  58. IPN localization of GRB000529
  59. GRB 000528 - WFC measurements
  60. IPN triangulation of GRB000519
  61. Re: GRB000508B : Optical observations
  62. GRB 000418, Optical observation
  63. GRB000508B, optical photometry
  64. Possible GRB-related phenomenon
  65. GRB 000424 Optical Observations
  66. The redshift of GRB 000418
  67. GRB000424, optical observations
  68. GRB 000429, optical observation
  69. GRB000418, Radio detection
  70. GRB000418, K'-band photometry
  71. GRB 000418, Optical Observation
  72. GRB 000418, optical observation
  73. GRB000424 Optical Observations
  74. GRB 000418, Optical Observation
  75. GRB000424, optical observations
  76. GRB000424, optical observations
  77. GRB 000424, Optical Observations
  78. GRB 000418, Optical Observation
  79. GRB000418, near-infrared observations
  80. BeppoSAX GRB000424
  81. Correction to IPN error box for GRB000419
  82. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  83. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  84. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  85. GRB 000408, optical observations
  86. Refined IPN error box for GRB000408
  87. GRB000301c results
  88. GRB000408: Optical CCD Observations from MIRO
  89. GRB000408, lotis optical observations
  90. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  91. GRB000326 Optical Observations
  92. GRB000301C - Addendum to GCN 623
  93. GRB000326, Further VLA observations
  94. GRB 000323, optical observations
  95. GRB 000326: Optical Observations
  96. GRB000326, Radio observations
  97. GRB 000307 optical observations
  98. Single error box for GRB000315
  99. GRB000313, Radio observations
  100. GRB000301C - B and R photometry

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