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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"

35267 results found.

  1. BeppoSAX ALERT: GRB001011
  2. GRB 001007, BVR-band observations
  3. GRB000926 - Amateur Optical Observations
  4. CONCAM null result on GRB001005
  5. IPN triangulation of GRB001007
  6. GRB 000926 : the host galaxy
  7. IPN triangulation of GRB001005
  8. GRB 000926 Chandra Observation
  9. IPN triangulation of GRB 001004
  10. Public availability of BeppoSAX data of GRB000926
  11. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  12. GRB 000926, Optical Decay
  13. GRB000926 - Optical observations
  14. GRB000926 - Optical observations
  15. GRB 000926: optical observations
  16. GRB 000926, Optical Observations
  17. GRB000926 K'-band Observation
  18. GRB000926 : increasing optical decay slope
  19. GRB000926 optical observations
  20. GRB000926 - Optical observations
  21. Re: GRB 000926, optical observation by Oksanen (vsnet-grb)
  22. J and K band observations of GRB 000926
  23. GRB 000926: Lightcurve Update and Predictions
  24. GRB 000926, optical observation by Oksanen (vsnet-grb)
  25. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  26. CONCAM crude optical limits before and after GRB000926
  27. GRB 000926: Preliminary R-band Lightcurve
  28. GRB 000926 HST/Chandra TOO Status
  29. Spectroscopic Redshift of GRB 000926
  30. GRB 000926, Optical Observation
  31. GRB 000926: Optical candidate
  32. Optical candidate for GRB000926
  33. IPN triangulation of GRB000926
  34. GRB 000911, BVRI field photometry
  35. GRB000911: Sub-millimeter observations
  36. IPN triangulation of GRB000925
  37. IPN triangulation of GRB000911
  38. IPN triangulation of GRB000910
  39. False GRB alarm from RXTE/ASM on 8 Sept 2000
  40. GRB 000830: Optical observations
  41. GRB000830: Optical observations
  42. GRB000830, TNG B-band observations
  43. GRB000830, BVRI field photometry
  44. GRB000830: Optical observations
  45. GRB000210, Optical observations
  46. Chandra Position of GRB000210
  47. "Snapshot" afterglow IDs and GRB 000830
  48. IPN triangulation of GRB000830
  49. HST/STIS observations of the host galaxy of GRB 980329
  50. HST/STIS observations of the chaotic environment of GRB 980613
  51. IPN localization of GRB000820
  52. GRB000801 & GRB000730, Gamma Ray Observations
  53. GRB000730, Gamma Ray Observations
  54. GRB000812, Radio observations
  55. IPN localization of GRB000812
  56. IPN localization of GRB000811
  57. GRB000801, Gamma Ray Observations
  58. GRB000801, VLT-Antu R-band observations
  59. GRB 991208 Host Galaxy Imaging
  60. Updated IPN coordinates for GRB000801
  61. IPN localization of GRB000801
  62. IPN localization of GRB000730B
  63. IPN localization of GRB000730B
  64. IPN localization of GRB000730
  65. GRB 990510: Possible detection of a host galaxy
  66. GRB 990510 Host Galaxy Discovery
  67. GRB 000727, optical observations
  68. IPN localization of GRB000727
  69. GRB 990705, HST/STIS observations of the host galaxy
  70. GRB 990712: Late time HST/STIS Observations
  71. GRB 991216, HST/STIS observations
  72. GRB981226, HST/STIS observations of the host galaxy
  73. GRB 000630: Detection of the Optical Afterglow
  74. GRB000630, Revised BVRI Field Photometry
  75. GRB000630, Optical Observations
  76. GRB000630, optical observations
  77. GRB000630, BVRI Field Photometry
  78. GRB000630, optical observations
  79. GRB000630: Optical observations
  80. possible optical counterpart of GRB 000630
  81. IPN triangulation of GRB000630
  82. GRB 000623, optical observations
  83. GRB 000620, optical observations
  84. GRB000418, HST/STIS Observations
  85. GRB990123: Late-time HST/STIS observations of the host
  86. GRB 990506, HST/STIS Observations of the Host Galaxy
  87. GRB000623
  88. GRB 000620: J-band observations
  89. GRB990308, HST/STIS observations of the host galaxy
  90. IPN annulus for GRB000620
  91. GRB000615, Radio observations
  92. GRB000607, optical observations
  93. GRB 000615: NIR further observations
  94. BeppoSAX ALERT: GRB000620
  95. GRB000620: BeppoSAX Alert
  96. GRB990123, HST/STIS observations of the host galaxy
  97. GRB 000615, near-infrared observations
  98. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  99. GRB000616 [IPN Position]
  100. GRB000615B [IPN Position]

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