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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"

35270 results found.

  1. V,R,I band observations of GRB000926
  2. The Likely Optical/Infrared Afterglow of GRB 001011
  3. HETE positions added to GCN
  4. BeppoSAX ALERT: GRB001011
  5. GRB 001007, BVR-band observations
  6. GRB000926 - Amateur Optical Observations
  7. CONCAM null result on GRB001005
  8. IPN triangulation of GRB001007
  9. GRB 000926 : the host galaxy
  10. IPN triangulation of GRB001005
  11. GRB 000926 Chandra Observation
  12. IPN triangulation of GRB 001004
  13. Public availability of BeppoSAX data of GRB000926
  14. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  15. GRB 000926, Optical Decay
  16. GRB000926 - Optical observations
  17. GRB000926 - Optical observations
  18. GRB 000926: optical observations
  19. GRB 000926, Optical Observations
  20. GRB000926 K'-band Observation
  21. GRB000926 : increasing optical decay slope
  22. GRB000926 optical observations
  23. GRB000926 - Optical observations
  24. Re: GRB 000926, optical observation by Oksanen (vsnet-grb)
  25. J and K band observations of GRB 000926
  26. GRB 000926: Lightcurve Update and Predictions
  27. GRB 000926, optical observation by Oksanen (vsnet-grb)
  28. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  29. CONCAM crude optical limits before and after GRB000926
  30. GRB 000926: Preliminary R-band Lightcurve
  31. GRB 000926 HST/Chandra TOO Status
  32. Spectroscopic Redshift of GRB 000926
  33. GRB 000926, Optical Observation
  34. GRB 000926: Optical candidate
  35. Optical candidate for GRB000926
  36. IPN triangulation of GRB000926
  37. GRB 000911, BVRI field photometry
  38. GRB000911: Sub-millimeter observations
  39. IPN triangulation of GRB000925
  40. IPN triangulation of GRB000911
  41. IPN triangulation of GRB000910
  42. False GRB alarm from RXTE/ASM on 8 Sept 2000
  43. GRB 000830: Optical observations
  44. GRB000830: Optical observations
  45. GRB000830, TNG B-band observations
  46. GRB000830, BVRI field photometry
  47. GRB000830: Optical observations
  48. GRB000210, Optical observations
  49. Chandra Position of GRB000210
  50. "Snapshot" afterglow IDs and GRB 000830
  51. IPN triangulation of GRB000830
  52. HST/STIS observations of the host galaxy of GRB 980329
  53. HST/STIS observations of the chaotic environment of GRB 980613
  54. IPN localization of GRB000820
  55. GRB000801 & GRB000730, Gamma Ray Observations
  56. GRB000730, Gamma Ray Observations
  57. GRB000812, Radio observations
  58. IPN localization of GRB000812
  59. IPN localization of GRB000811
  60. GRB000801, Gamma Ray Observations
  61. GRB000801, VLT-Antu R-band observations
  62. GRB 991208 Host Galaxy Imaging
  63. Updated IPN coordinates for GRB000801
  64. IPN localization of GRB000801
  65. IPN localization of GRB000730B
  66. IPN localization of GRB000730B
  67. IPN localization of GRB000730
  68. GRB 990510: Possible detection of a host galaxy
  69. GRB 990510 Host Galaxy Discovery
  70. GRB 000727, optical observations
  71. IPN localization of GRB000727
  72. GRB 990705, HST/STIS observations of the host galaxy
  73. GRB 990712: Late time HST/STIS Observations
  74. GRB 991216, HST/STIS observations
  75. GRB981226, HST/STIS observations of the host galaxy
  76. GRB 000630: Detection of the Optical Afterglow
  77. GRB000630, Revised BVRI Field Photometry
  78. GRB000630, Optical Observations
  79. GRB000630, optical observations
  80. GRB000630, BVRI Field Photometry
  81. GRB000630, optical observations
  82. GRB000630: Optical observations
  83. possible optical counterpart of GRB 000630
  84. IPN triangulation of GRB000630
  85. GRB 000623, optical observations
  86. GRB 000620, optical observations
  87. GRB000418, HST/STIS Observations
  88. GRB990123: Late-time HST/STIS observations of the host
  89. GRB 990506, HST/STIS Observations of the Host Galaxy
  90. GRB000623
  91. GRB 000620: J-band observations
  92. GRB990308, HST/STIS observations of the host galaxy
  93. IPN annulus for GRB000620
  94. GRB000615, Radio observations
  95. GRB000607, optical observations
  96. GRB 000615: NIR further observations
  97. BeppoSAX ALERT: GRB000620
  98. GRB000620: BeppoSAX Alert
  99. GRB990123, HST/STIS observations of the host galaxy
  100. GRB 000615, near-infrared observations

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