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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"

35262 results found.

  1. GRB 000926 : the host galaxy
  2. IPN triangulation of GRB001005
  3. GRB 000926 Chandra Observation
  4. IPN triangulation of GRB 001004
  5. Public availability of BeppoSAX data of GRB000926
  6. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  7. GRB 000926, Optical Decay
  8. GRB000926 - Optical observations
  9. GRB000926 - Optical observations
  10. GRB 000926: optical observations
  11. GRB 000926, Optical Observations
  12. GRB000926 K'-band Observation
  13. GRB000926 : increasing optical decay slope
  14. GRB000926 optical observations
  15. GRB000926 - Optical observations
  16. Re: GRB 000926, optical observation by Oksanen (vsnet-grb)
  17. J and K band observations of GRB 000926
  18. GRB 000926: Lightcurve Update and Predictions
  19. GRB 000926, optical observation by Oksanen (vsnet-grb)
  20. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  21. CONCAM crude optical limits before and after GRB000926
  22. GRB 000926: Preliminary R-band Lightcurve
  23. GRB 000926 HST/Chandra TOO Status
  24. Spectroscopic Redshift of GRB 000926
  25. GRB 000926, Optical Observation
  26. GRB 000926: Optical candidate
  27. Optical candidate for GRB000926
  28. IPN triangulation of GRB000926
  29. GRB 000911, BVRI field photometry
  30. GRB000911: Sub-millimeter observations
  31. IPN triangulation of GRB000925
  32. IPN triangulation of GRB000911
  33. IPN triangulation of GRB000910
  34. False GRB alarm from RXTE/ASM on 8 Sept 2000
  35. GRB 000830: Optical observations
  36. GRB000830: Optical observations
  37. GRB000830, TNG B-band observations
  38. GRB000830, BVRI field photometry
  39. GRB000830: Optical observations
  40. GRB000210, Optical observations
  41. Chandra Position of GRB000210
  42. "Snapshot" afterglow IDs and GRB 000830
  43. IPN triangulation of GRB000830
  44. HST/STIS observations of the host galaxy of GRB 980329
  45. HST/STIS observations of the chaotic environment of GRB 980613
  46. IPN localization of GRB000820
  47. GRB000801 & GRB000730, Gamma Ray Observations
  48. GRB000730, Gamma Ray Observations
  49. GRB000812, Radio observations
  50. IPN localization of GRB000812
  51. IPN localization of GRB000811
  52. GRB000801, Gamma Ray Observations
  53. GRB000801, VLT-Antu R-band observations
  54. GRB 991208 Host Galaxy Imaging
  55. Updated IPN coordinates for GRB000801
  56. IPN localization of GRB000801
  57. IPN localization of GRB000730B
  58. IPN localization of GRB000730B
  59. IPN localization of GRB000730
  60. GRB 990510: Possible detection of a host galaxy
  61. GRB 990510 Host Galaxy Discovery
  62. GRB 000727, optical observations
  63. IPN localization of GRB000727
  64. GRB 990705, HST/STIS observations of the host galaxy
  65. GRB 990712: Late time HST/STIS Observations
  66. GRB 991216, HST/STIS observations
  67. GRB981226, HST/STIS observations of the host galaxy
  68. GRB 000630: Detection of the Optical Afterglow
  69. GRB000630, Revised BVRI Field Photometry
  70. GRB000630, Optical Observations
  71. GRB000630, optical observations
  72. GRB000630, BVRI Field Photometry
  73. GRB000630, optical observations
  74. GRB000630: Optical observations
  75. possible optical counterpart of GRB 000630
  76. IPN triangulation of GRB000630
  77. GRB 000623, optical observations
  78. GRB 000620, optical observations
  79. GRB000418, HST/STIS Observations
  80. GRB990123: Late-time HST/STIS observations of the host
  81. GRB 990506, HST/STIS Observations of the Host Galaxy
  82. GRB000623
  83. GRB 000620: J-band observations
  84. GRB990308, HST/STIS observations of the host galaxy
  85. IPN annulus for GRB000620
  86. GRB000615, Radio observations
  87. GRB000607, optical observations
  88. GRB 000615: NIR further observations
  89. BeppoSAX ALERT: GRB000620
  90. GRB000620: BeppoSAX Alert
  91. GRB990123, HST/STIS observations of the host galaxy
  92. GRB 000615, near-infrared observations
  93. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  94. GRB000616 [IPN Position]
  95. GRB000615B [IPN Position]
  96. GRB000615, further R-band photometry
  97. GRB 000615: NIR observations
  98. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  99. GRB000615, R-band photometry
  100. GRB980425, HST/STIS observations of the host galaxy

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